Chinese Journal of Radiation Oncology

中华放射肿瘤学杂志

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Chinese Journal of Radiation Oncology

	2015 Vol.24 Issue.5 Published 2015-08-31

	Head and Neck Tumors Abdominal Tumors Review Thoracic Tumors Physics·Biology·Technique

Thoracic Tumors

	479	Predictive factors for radiation-induced lung injury in locally advanced non-small cell lung cancer after intensity-modulated radiotherapy
		Sun Shuai, Chen Xinyuan, Wang Jingbo, Ji Zhe, Bi Nan, Zhou Zongmei, Feng Qinfu, Hui Zhouguang, Liang Jun, Xiao Zefen, Lyu Jima, Wang Xiaozhen, Yin Weibo, Wang Lyuhua
		Objective To investigate the incidence of radiation-induced lung injury (RILI) in patients with locally advanced non-small cell lung cancer (LA-NSCLC) after involved-field intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy, and to figure out the predictive factors for RILI. Methods Two hundred and fifty-six patients with stage Ⅲ NSCLC who were treated without surgery in our hospital from January 2007 to December 2011 were enrolled as subjects. All patients received involved-field IMRT with a median dose of 60 Gy (50-70 Gy) in 30 fractions. In all patients, 109 patients (42.6%) received concurrent chemotherapy. The National Cancer Institute Common Terminology Criteria for Adverse Events Version 3.0 was used to evaluate the RILI grade. The incidence of grade ≥2 RILI (symptomatic RILI, SRILI) within 6 months after radiotherapy served as the end point. The predictive factors for RILI were analyzed using logistic regression model. Results In all patients, 215(84%) were male, and 41(16%) were female. The mean age at diagnosis was 59.2 years. Forty-three (16.7%) patients had grade ≥2 RILI. The mean duration between the incidence of RILI and the beginning of radiotherapy was 64 days (20-169 days). Univariate analysis showed that smoking, peripheral or central tumor location, mean lung dose (MLD) for both lungs, and V₅-V₂₀ for both lungs were suspected to be associated with the development of SRILI (P=0.108,0.106,0.030,0.049). Multivariate analysis showed the MLD and V₅-V₂₀ for both lungs were independent predictive factors for SRILI P=(0.048). Conclusions For patients with LA-NSCLC treated with involved-field IMRT, the MLD and the volume of low-dose region in dose volume histogram for both lungs are significantly correlated with the incidence of SRILI.
		2015 Vol. 24 (5): 479-483 [Abstract] ( 3827 ) [HTML 1KB] [ PDF 347KB] ( 0 )

	484	Significance of postoperative radiotherapy in treatment of stage T_1-2N₀M₀ small-cell lung cancer
		Liu Weishuai^*,Zhao Lujun,Zhang Baozhong,Gong Linlin,Guan Yong,Wang Ping
		Objective To investigate the impact of postoperative radiotherapy (PORT) on the prognosis of early-stage small-cell lung cancer (SCLC). Methods The clinical data of 71 patients who were clinically diagnosed with stage T_1-2N₀M₀ SCLC and underwent radical resection surgery in our hospital from 1997 to 2010 were retrospectively analyzed. Thirty-one patients received PORT, and fifty-five patients received preoperative or postoperative chemotherapy. The locoregional recurrence (LRR), distant metastasis, and overall survival (OS) rates were calculated using the Kaplan-Meier method. The log-rank test was used for survival difference analysis and univariate prognostic analysis. The multivariate prognostic analysis was made by the Cox regression model. Results The 5-year sample size was 32. The 5-year OS and LRR rates were 52% and 22%, respectively. PORT had no significant impact on OS rate (P=0.524). There were no significant differences in median OS and 5-year LRR rates between node-negative patients treated with and without PORT (47.3 vs. 96.8 months, P=0.561;39% vs. 23%, P=0.934). In the node-positive patients, patients treated with PORT had a significantly higher median OS rate and a significantly lower 5-year LRR rate than those treated without PORT (66.7 vs. 34.6 months, P=0.016;5% vs. 75%, P=0.004). The distant metastasis rate was 30% in all patients, and PORT had no significant impact on the distant metastasis rate (P=0.576). Conclusions PORT significantly reduces LRR rate and improves OS rate in node-positive patients with SCLC. However, it slightly reduces OS rate in node-negative patients. Therefore, PORT is recommended for node-positive patients with SCLC.
		2015 Vol. 24 (5): 484-487 [Abstract] ( 3087 ) [HTML 1KB] [ PDF 292KB] ( 0 )

	488	Comparison of efficacy of different fractionation schedules in radiotherapy for extensive-stage small cell lung cancer
		Xu Liming,Zhao Lujun,Chen Xiuli,Wang Daquan,Chen Xi,Wang Xin,Gong Linlin,Pang Qingsong,Wang Jun,Yuan Zhiyong,Wang Ping
		Objective To evaluate the correlation of different fractionation schedules in radiotherapy with the local control (LC) and overall survival (OS) rates in patients with extensive-stage small cell lung cancer (ES-SCLC), and to figure out the relationship between different fractionation schedules in radiotherapy and the prognosis of ES-SCLC. Methods One hundred and ten patients newly diagnosed with ES-SCLC from February 2010 to March 2015 received chemoradiotherapy. According to the radiation dose, all patients were divided into hypo-fractionation group (30-45 Gy/3 Gy/10-15 f, n=31) and conventional fractionation group (54-60 Gy/1.8-2.0 Gy/27-30 f, n=79). In all patients, 90.9% had stage Ⅳ SCLC;21 patients had brain metastasis;39 patients were treated with prophylactic cranial irradiation (PCI). The Kaplan-Meier method was used to calculate the survival time and log-rank test was used for between-group comparison. Between-group comparison of categorical data was made by χ² test. Results The number of patients followed-up were 85 at 2-years. In all patients, the 2-year OS, progression-free survival (PFS), and LC rates were 27.7%, 17.5%, and 38.9%, respectively. The hypo-fractionation group had similar prognosis to the conventional fractionation group. There were no significant differences in the 2-year OS, PFS, and LC rates between the two groups (35% vs. 26%, P=0.886;18% vs. 16%, P=0.560;67% vs. 36%, P=0.159). There was also no significant difference in the 2-year OS rate between patients treated with and without PCI (44% vs. 18%, P=0.044). In 84 patients with treatment failure, 11 had local recurrence, 41 had distant metastasis, and 32 had local recurrence plus distant metastasis. Conclusions The hypofractionated radiotherapy has similar efficacy but substantially shortened radiation time compared with conventionally fractionated radiotherapy. The palliative hypofractionated radiotherapy requires further study for ES-SCLC.
		2015 Vol. 24 (5): 488-492 [Abstract] ( 3094 ) [HTML 1KB] [ PDF 0KB] ( 0 )

	493	A comparative study of computed tomography and magnetic resonance imaging in pathological diagnosis of regional lymph node metastasis
		Wang Lan, Liu Lihong, Han Chun, Zhu Shuchai, Liu Lei, Shi Gaofeng, Liu Junfeng, Liu Shutang, Wang Qi
		Objective To evaluate the efficacy of computed tomography (CT) and diffusion-weighted magnetic resonance imaging (DWMRI) in the diagnosis of regional lymph node metastasis in thoracic carcinoma, and to figure out the methods and thresholds for delineation of lymph nodes with higher reasonability and accuracy. Methods A total of 43 patients with thoracic carcinoma, including 35 patients with esophageal cancer and 8 patients with non-small cell lung cancer, were enrolled as subjects from 2012 to 2013. All patients received abdominal CT scan and DWMRI examination one week before surgery, and regional lymph node metastasis was diagnosed based on the images of CT scan or DWMRI. With the postoperative pathology as the gold standard, the diagnostic efficacy was evaluated and compared between the two methods. The two sets of obtained images were analyzed using the χ²-test. Results The sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and Youden’s index of CT versus DWMRI in the diagnosis of regional lymph node metastasis were 57.1% vs. 60.0%, 96.3% vs. 98.9%, 93.8% vs. 96.5%, 50.0% vs. 77.8%, 97.2% vs. 97.4%, and 53.4% vs. 58.9%, respectively;the specificity, accuracy, and positive predictive value of DWMRI were significantly superior to those of CT (P=0.005,0.038,0.022). Twenty out of forty lymph nodes diagnosed by CT scan were false positive, and 15(75%) of them could be corrected by DWMRI. Fifteen out of forty lymph nodes diagnosed by CT scan were false negative, and 3(20%) of them could be recognized by DWMRI. In all 35 metastatic lymph nodes, 5 lymph nodes had no apparent swelling on images, and 13(43.3%) out of the other 30 lymph nodes had a short diameter less than 1.0 cm. Conclusions CT scan has apparent limitation in the diagnosis of regional lymph node metastasis. Many metastatic lymph nodes would be missed if a short diameter not lessthan 1.0 cm is the only standard for target volume delineation. With superior specificity, accuracy, and positive predictive value to CT in the diagnosis of regional lymph node metastasis, DWMRI can effectively rule out non-cancerous intumescent lymph nodes and recognize some of small metastatic lymph nodes.
		2015 Vol. 24 (5): 493-496 [Abstract] ( 3063 ) [HTML 1KB] [ PDF 319KB] ( 0 )

	497	A comparative study of planning target volumes based on three-dimensional computed tomography, four-dimensional computed tomography, and positron emission tomography-computed tomography in thoracic esophageal cancer
		Guo Yanluan,Li Jianbin,Li Yankang,Wang Wei,Ma Zhifang,Liang Chaoqian,Xing Jun,Duan Yili
		Objective To investigate the differences in position and volume between planning target volumes (PTV) based on positron emission tomography-computed tomography (PET-CT) images with an standardized uptake value (SUV) no less than 2.5, 20% of the maximum SUV (SUV_max), or 25% of SUV_max, three-dimensional (3D) CT, and four-dimensional (4D) CT in thoracic esophageal cancer. Methods Eighteen patients with thoracic esophageal cancer sequentially received chest 3DCT, 4DCT, and[18F]fluoro-2-deoxy-D-glucose (FDG) PET-CT scans. PTV_3D was obtained by conventional expansion of 3DCT images;PTV_4D was obtained by fusion of target volumes from 10 phases of 4DCT images. The internal gross tumor volumes (IGTV), IGTV_PET2.5, IGTV_PET20%, and IGTV_PET25%, were generated based on PET-CT images with an SUV no less than 2.5, 20% of SUV_max, and 25% of SUV_max, respectively. These IGTVs were expanded longitudinally by 3.5 cm and radically by 1 cm to make PTV_PET2.5, PTV_PET20%, and PTV_PET25%, respectively. Results PTV_3D was significantly larger than both PTV_4D and PTV_PET(P=0.000－0.044), while there was no significant difference between PTV_4D and PTV_PET(P=0.216－0.633). The mutual degrees of inclusion (DIs) between PTV_3D and PTV_4D were 0.70 and 0.95, respectively, which were negatively correlated with 3D-Vector (P=0.039). The mutual DIs between PTV_PET2.5, PTV_PET20%, and PTV_PET25% were 0.74, 0.72, 0.78, 0.73, 0.77, and 0.70, respectively, which showed no correlation with 3D-Vector (P=0.150－0.822). The mutual DIs between PTV_3D and PTV_PET were 0.86, 0.84, 0.88, 0.63, 0.67, and 0.59, respectively. Conclusions It is difficult to achieve complete volumetric overlap of PTVs based on 3DCT, 4DCT and PET-CT in thoracic esophageal cancer due to different target volume information. PET scan during free breathing should be used with caution to generate PTVs in thoracic esophageal cancer.
		2015 Vol. 24 (5): 497-501 [Abstract] ( 3896 ) [HTML 1KB] [ PDF 344KB] ( 0 )

	544	Value of magnetic resonance sialography in evaluation of salivary gland function in patients with nasopharyngeal carcinoma treated with radiotherapy
		Zhang Yu^*,Qu Song,Su Danke,Li Ling,Zhao Wei,Pei Su,Chen Xiaoqian,Liang Zhongguo,Liang Zhenqiang,Zhu Xiaodong
		Objective To investigate the feasibility of magnetic resonance sialography (MRS) in the evaluation of salivary gland function in patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy. Methods The MRS images of parotid and submandibular glands were collected in resting and stimulated states among 32 patients with nasopharyngeal carcinoma before and after radiotherapy. The visibility of the salivary ducts and radiation-induced xerostomia were evaluated, and the relationship between radiation-induced acute xerostomia grade and MRS score was analyzed. Comparison of the visibility and score between two groups was made by paired t test, and the correlation between acute xerostomia grade and MRS score was determined using the Spearman rank correlation method. Results Both the visibility of salivary duct and MRS score were significantly reduced after radiotherapy (P=0.000,P=0.000). There were significant differences in the variation of MRS scores of the parotid (DPS) and submandibular glands (DSS) from the resting state to the stimulated state between patients with severe and non-severe acute xerostomia (P=0.009;P=0.005). There were no significant differences in MRS scores of the parotid and submandibular glands in resting and stimulated states between patients with severe and non-severe acute xerostomia (P=0.881, P=0.305, P=0.327, P=0.229). The Spearman correlation analysis showed that the acute xerostomia grade was negatively correlated with DPS and DSS (R=－0.472, P=0.006;R=－0.482, P=0.005). Conclusions MRS score is correlated with xerostomia grade. MRS can be used to evaluate the salivary gland function in patients with nasopharyngeal carcinoma treated with radiotherapy.
		2015 Vol. 24 (5): 544-547 [Abstract] ( 3706 ) [HTML 1KB] [ PDF 966KB] ( 0 )

Abdominal Tumors

	502	Value of radiotherapy for early-stage Waldeyer’s ring diffuse large B-cell lymphoma in the rituximab era
		Xu Yonggang, Li Yexiong,Wang Weihu, Jin Jing, Wang Shulian, Liu Yueping, Song Yongwen, Ren Hua, Fang Hui, Liu Qingfeng, Wu Runye, Qi Shunan, Chen Bo
		Objective To evaluate the value of radiotherapy following rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP)-based chemotherapy for patients with early-stage Waldeyer’s ring diffuse large B-cell lymphoma (WR-DLBCL). Methods Eighty-three patients diagnosed with early-stage WR-DLBCL who were admitted to our hospital from 2000 to 2013 were enrolled in the study. In these patients, twenty-five had stage Ⅰ disease and fifty-eight had stage Ⅱ disease. All patients received R-CHOP-based chemotherapy with (n=62) or without (n=21) involved-field radiotherapy (Waldeyer’s ring plus cervical lymph nodes). The overall survival (OS), progression-free survival (PFS), and local-regional control (LRC) rates were calculated using the Kaplan-Meier method. The univariate analysis was performed using the log-rank method. The multivariate analysis was performed using the Cox regression model. Results In all patients, the 5-year sample size was 18;the 5-year OS, PFS, and LRC rates were 89%, 84%, and 90%, respectively. According to the univariate analysis, patient age greater than 60 years, an increased lactate dehydrogenase level, Eastern Cooperative Oncology Group (ECOG) performance status no less than 2, and International Prognostic Index (IPI) no less than 2 were poor prognostic factors. Patient age greater than 60 years, a tumor size no less than 5 cm, ECOG performance status no less than 2, and IPI no less than 2 were influencing factors for PFS and LRC rates. In addition to the treatment with rituximab, patients treated with consolidative radiotherapy had significantly higher PFS and LRC rates (94% vs. 58%, P=0.003;100% vs. 61%, P=0.000) as well as slightly higher OS rate(94% vs. 71%,P=0.063) than those treated without radiotherapy. Conclusions Consolidative radiotherapy following R-CHOP-based chemotherapy significantly improves PFS, LRC, and probably OS rates for early-stage WR-DLBCL. This conclusion still needs to be confirmed by prospective studies with a large sample size.
		2015 Vol. 24 (5): 502-505 [Abstract] ( 2272 ) [HTML 1KB] [ PDF 747KB] ( 0 )

	506	Prognostic value of primary tumor site in early breast cancer patients with one to three positive axillary lymph nodes after radical surgery
		Niu Shaoqing^*,Wen Ge,Zhang Yujing,Wang Chengtao,Li Yiyang,Huang Xiaobo,Guan Xunxing,Wen Bixiu
		Objective To explore the predictive value of primary tumor site for loco-regional recurrence (LRR) in early breast cancer patients with one to three positive axillary lymph nodes after radical surgery. Methods The clinical data of 656 patients pathologically diagnosed with pT_1-2N₁M₀ breast cancer who received radical surgery without postoperative radiotherapy in our hospital from 1998 to 2010 were retrospectively analyzed. In those patients, 156 had primary tumor located in the inner quadrant, 45 in the central quadrant, and 455 in the outer quadrant. LRR and local recurrence-free survival (LRFS) were end points. The Kaplan-Meier method was used to estimate LRR and LRFS rates. The log-rank test was used for survival difference analysis and univariate prognostic analysis. Multivariate analysis was performed using the Cox regression model. Results The 5-and 10-year sample sizes were 416 and 191, respectively. The 5-and 10-year LRR rates were 8.6% and 12.9%, respectively, while the 5-and 10-year LRFS rates were 86.2% and 76.4%, respectively. The univariate analysis indicated that age, pT stage, Ki67 level, molecular classification, and primary tumor in the inner quadrant were significant influencing factors for LRR (P=0.000,0.006,0.017,0.004,0.000). The multivariate analysis showed that age no greater than 35 years, primary tumor in the inner quadrant, and non-luminal subtype in molecular classification were independent prognostic factors for LRR and LRFS (P=0.0012,0.012,0.005). With an increasing number of risk factors(≥2), patients with primary tumor in the inner quadrant had a dramatically increased LRR rate and a reduced LRFS rate, while patients with primary tumor in the outer or central quadrant kept the same LRR and LRFS rates. Conclusions The primary tumor site holds promise for prediction of LRR and LRFS in patients with pT_1-2N₁M₀ breast cancer after radical surgery. Patients with primary tumor located in the inner quadrant have a high LRR rate and a low LRFS rate, which provides an excellent predictor for the risk of recurrence in patients with high-risk breast cancer.
		2015 Vol. 24 (5): 506-510 [Abstract] ( 3271 ) [HTML 1KB] [ PDF 344KB] ( 0 )

	511	Relationship between prostate volume reduction and neoadjuvant hormone therapy duration in prostate cancer radiotherapy
		Li Hongzhen,Gao Xianshu,Ji Chen,Li Xiaoying,Qin Shangbin,Qi Xin,Wang Qingguo,Zhang Min,Li Xiaomei
		Objective To study the relationship between changes in prostate volume and neoadjuvant hormone therapy (NHT) duration in prostate cancer radiotherapy. Methods Fifty patients with prostate cancer who received NHT were enrolled in the study continuously. The diameters along the x-, y-, and z-axes of the prostate were measured, and the volume of prostate was calculated weekly during radiotherapy. The relationship of prostate volume reduction with NHT duration, prostate volume before radiotherapy, and prostate cancer risk groups was analyzed during radiotherapy. Results The prostate volume in all patients decreased after radiotherapy. Patients with short NHT duration had larger changes in prostate volume and diameters than those with long NHT duration. Compared with those with a large prostate volume, patients with a normal prostate volume had larger changes in prostate volume and diameters long three axes after 7 weeks of radiotherapy, shorter NHT duration before radiotherapy, and lower risk of prostate cancer. In patients with low-and medium-risk prostate cancer, the prostate volumes were significantly reduced to 68.10% and 78.70%, respectively, of those before radiotherapy after no more than 4 months of NHT (P=0.002), but remained similar after more than 4 months of NHT. In patients with high-risk and more severe prostate cancer, the prostate volumes were significantly reduced to 76.59% and 85.46%, respectively, of those before radiotherapy after no more than 6 months of NHT (P=0.001), but remained similar after more than 6 months of NHT. Conclusions The changes in prostate volume and diameters along three axes during radiotherapy become smaller with longer NHT duration. Patients with low-or medium-risk prostate cancer have slight changes in prostate volume after more than 4 months of NHT, while patients with high-risk or locally advanced prostate cancer have slight changes in prostate volume after more than 6 months of NHT.
		2015 Vol. 24 (5): 511-515 [Abstract] ( 3007 ) [HTML 1KB] [ PDF 1262KB] ( 0 )

	516	An analysis of efficacy of pelvic radiotherapy and prognostic factors for stage IV rectal cancer
		Ren Hua,Jing Hao,Jin Jing,Fang Hui,Wang Xin,Li Ning,Wang Weihu,Wang Shulian,Song Yongwen,Liu Yueping,Liu Xinfan,Yu Zihao,Li Yexiong
		Objective To retrospectively analyze the efficacy of pelvic radiotherapy and prognostic factors for stage IV rectal cancer. Methods From 2000 to 2010, 61 patients with stage IV rectal cancer who received pelvic radiotherapy with or without rectal surgery were enrolled as subjects. In those patients, 19 had both primary and metastatic tumors resected, 19 had only primary tumor resected, and 23 received pelvic radiotherapy with both primary and metastatic tumors intact. The Kaplan-Meier method was used to estimate survival rates, and the log-rank test was used for survival difference analysis and univariate prognostic analysis. Comparison of disaggregated data was made by Fisher′s exact test. Results The 5-year overall survival (OS) and progression-free survival (PFS) rates in all patients were 26% and 17%, respectively. The prognostic analysis showed that stage T₄, positive node, age greater than 65 years, metastasis outside the liver, and intact primary tumor were prognostic factors for OS, while stage T₄, positive node, and intact primary tumor were prognostic factors for PFS. In patients with both primary and metastatic tumors resected, 5-year OS rates in patients treated with and without pelvic radiotherapy were 67% and 32%, respectively (P=0.119). In patients with intact metastatic tumor, 2-year OS rates in patients with resected and intact primary tumor were 52% and 27%, respectively (P=0.057). Only 4 patients who received pelvic radiotherapy alone for primary rectal tumor needed ostomy. Conclusions The value of postoperative pelvic radiotherapy still needs further studies in patients with stage IV rectal cancer and resectable metastatic tumor. Pelvic radiotherapy for primary tumor achieves definitive treatment outcomes in patients with stage IV rectal cancer and unresectable primary and metastatic tumors.
		2015 Vol. 24 (5): 516-520 [Abstract] ( 3644 ) [HTML 1KB] [ PDF 303KB] ( 0 )

	521	Chemoradiotherapy for locally advanced rectal cancer:a clinical analysis of 47 patients
		Zhang Luning^*,You Kaiyun,Huang Rong,Xiao Weiwei,Chen Li,Chang hui,Qiu bo,Zeng Zhifan,Gao Yuanhong
		Objective To evaluate the efficacy of chemoradiotherapy alone and prognostic factors for locally advanced rectal cancer. Methods The clinical data of 47 patients with locally advanced rectal cancer who were admitted to our hospital and mostly treated with chemoradiotherapy alone from 2003 to 2010 were retrospectively analyzed. Three of the patients received radiotherapy alone. The Kaplan-Meier method was used to estimate overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) rates, and the log-rank test was used for survival difference analysis and univariate prognostic analysis. The Cox regression model was used for multivariate prognostic analysis. Results In all patients, the 3-and 5-year OS rates were 53.2% and 33.2%, respectively, while the 3-and 5-year PFS rates were 37% and 31%, respectively. During the follow-up, 15 patients (32%) had local progression with PFS of 1-60 months (median PFS, 14 months);23 patients (49%) had distant metastasis with DMFS of 2-60 months (median DMFS, 17 months). Patients treated with high-dose radiotherapy had significantly lower 3-and 5-year local progression rates than patients treated with medium-dose radiotherapy (11% vs. 54%;11% vs. 57%;P=0.004). After chemoradiotherapy, 9 patients (19%) had clinical complete response (cCR), and the 3-and 5-year OS and PFS rates in those patients were all 8/9. The univariate analysis indicated that tumor distance from the anus and cCR were influencing factors for prognosis (P=0.026;P=0.000). However, the multivariate analysis showed that cCR was the only influencing factor for survival (HR=12.24;95%CI, 1.64-91.29;P=0.015). Conclusions Chemoradiotherpay or radiotherapy alone is effective and safe in the treatment of patients with locally advanced rectal cancer who have to give up surgery or have unresectable tumors. High-dose radiotherapy may improve local control rate. Complete response to chemoradiotherapy predicts satisfactory treatment outcomes.
		2015 Vol. 24 (5): 521-524 [Abstract] ( 2828 ) [HTML 1KB] [ PDF 315KB] ( 0 )

	525	Relationship between excision repair cross-complementation group 1 methylation and sensitivity to cisplatin-based concurrent chemoradiotherapy in cervical squamous cell carcinoma
		Bai Zhoulan,Ma Jianping,He Jianli,Zhang Yuhui,Hai Ping,Feng Yangyang,Wang Yangyang,Zhe Hong
		Objective To investigate the correlation of the excision repair cross-complementation group 1(ERCC1) gene methylation status with sensitivity to cisplatin-based concurrent chemoradiotherapy and clinical pathological characteristics in patients with cervical squamous cell carcinoma (CSCC). Methods Methylation specific polymerase chain reaction was used to determine the ERCC1 gene methylation status in cervical tissue from 20 healthy people and 60 patients with CSCC. All patients with CSCC were treated with cisplatin-based concurrent chemoradiotherapy. The treatment outcomes were evaluated using the Response Evaluation Criteria in Solid Tumors. Based on the treatment outcomes, patients with a complete response were assigned to chemoradiotherapy-sensitive group, and patients with a partial response, stable disease, or progressive disease were assigned to chemoradiotherapy-resistant group. Comparison of the ERCC1 gene methylation status between the two groups was made by χ² test, and multivariate logistic regression analysis was used to analyze the relationship of the ERCC1 gene methylation status with various clinical pathological characteristics and sensitivity to chemoradiotherapy. Results The ERCC1 gene methylation rate was significantly higher in cervical tissue with CSCC than in normal cervical tissue (60% vs. 0%, P=0.000). The multivariate analysis showed that ERCC1 gene methylation was an independent influencing factor for sensitivity to cisplatin-based concurrent chemoradiotherapy in CSCC (P=0.022);ERCC1 gene methylation was significantly correlated with histological grade of CSCC (P=0.030);there wasno significant relationship of ERCC1 gene methylation with clinical pathological characteristics including age tumor size, lymph node metastasis, FIGO stage, and pretreatment hemoglobin and platelet count (P=0.729,0.707,0.340,0.747,0.073,1.000). Conclusions The ERCC1 gene promoter methylation status may be involved in the development and progression of CSCC. It may also influence the sensitivity of patients with CSCC to cisplatin-based concurrent chemoradiotherapy by playing a role in cell differentiation.
		2015 Vol. 24 (5): 525-528 [Abstract] ( 3320 ) [HTML 1KB] [ PDF 316KB] ( 0 )

	532


		2015 Vol. 24 (5): 532-533 [Abstract] ( 2483 ) [HTML 1KB] [ PDF 207KB] ( 0 )

Head and Neck Tumors

	529	An analysis of efficacy of intensity-modulated radiotherapy with concurrent chemotherapy for stage T_1-2N₁ nasopharyngeal carcinoma
		Jiang Shaona^*,Li Fei,Xie Li,Dou Shengjin,Zhu Guopei,Hu Chaosu
		Objective To retrospectively analyze the efficacy and toxicity of intensity-modulated radiotherapy (IMRT) alone and IMRT with concurrent chemotherapy (CRT) in the treatment of early-stage nasopharyngeal carcinoma (NPC) using pairwise group comparison. Methods A total of 98 patients with stage T_1-2N₁M₀ NPC were treated with IMRT alone or CRT from 2009 to 2010, and 39 pairs out of them were selected for comparison of efficacy and toxicity. The survival rates were calculated using the Kaplan-Meier method and analyzed using the log-rank test. Results The 3-year follow-up rate was 95%. There were no significant differences in the 3-year overall survival (OS), progression-free survival (PFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) rates between the IMRT alone group and the CRT group (97% vs. 95%, P=0.411;97% vs. 92%, P=0.301;97% vs. 97%, P=0.606;100% vs. 92%, P=0.082). The incidence rates of leucopenia, anemia, and thrombocytopenia were significantly higher in the CRT group than in the IMRT alone group (P=0.000;P=0.000;P=0.000). There were no significant differences in the incidence rates of grade 3 oral mucositis and hearing loss between the IMRT alone group and the CRT group (26% vs. 23%, P=0.093;41% vs. 62%, P=0.100). Conclusions CRT fails to increase the OS, PFS, and LRFS rates and reduce the DMFS rate in patients with stage T_1-2N₁ NPC. Moreover, CRT results in higher incidence rates of hematotoxicity, grade 3 mucositis, and hearing loss than IMRT alone.
		2015 Vol. 24 (5): 529-531 [Abstract] ( 3017 ) [HTML 1KB] [ PDF 500KB] ( 0 )

	534	An analysis of multimodal treatment outcomes and patterns of treatment failure in esthesioneuroblastoma
		Yin Zhenzhen,Gao Li,Luo Jingwei,Yi Junlin,Huang Xiaodong,Wang Kai,Qu Yuan,Zhang Shiping,Li Suyan,Xiao Jianping,Xu Guozhen
		Objective To evaluate the multimodal treatment outcomes and patterns of treatment failure in esthesioneuroblastoma at a single institution. Methods One hundred and twelve patients who were newly diagnosed with esthesioneuroblastoma but no distant metastasis in our institution from 1979 to 2014 were retrospectively analyzed. The treatment modes, outcomes, and patterns of treatment failure in these patients were analyzed. According to the modified Kadish staging system, the numbers of patients with stage A, B, C, and D esthesioneuroblastoma were 1, 23, 60, and 28, respectively. Fifty-one patients received surgery and postoperative radiotherapy with or without chemotherapy;forty-six patients received radiotherapy with or without chemotherapy;eleven patients received preoperative radiotherapy and surgery with or without chemotherapy;three patients received surgery with or without chemotherapy;one patient received chemotherapy alone. The survival rates were calculated using the Kaplan-Meier method. Results In all patients, the 5-year sample size was 44, and the 5-year overall survival (OS) and disease-free survival (DFS) rates were 66.4% and 54.7%, respectively. The 5-year OS and DFS rates were 91% and 82% in patients who received preoperative radiotherapy and surgery with or without chemotherapy, 80% and 66% in patients who received surgery and postoperative radiotherapy with or without chemotherapy, and 46% and 37% in patients who received radiotherapy with or without chemotherapy. Three patients treated with surgery alone had relapse of the disease;one patient treated with palliative chemotherapy survived 6 months. Treatment failed in 47(42%) out of 112 patients. In patients with failed treatment, 53% had distant metastasis as the first pattern of treatment failure, 36% had locoregional relapse, and 11% had concurrent distant metastasis and locoregional relapse. Conclusions Surgery combined with radiotherapy is still the recommended multimodal treatment regimen for esthesioneuroblastoma. The multimodal treatment achieves satisfactory local-regional control rate and treatment outcomes in the treatment of esthesioneuroblastoma. The major pattern of treatment failure is distant metastasis.
		2015 Vol. 24 (5): 534-537 [Abstract] ( 3148 ) [HTML 1KB] [ PDF 859KB] ( 0 )

	540	Impacts of radiation dose on survival in 72 patients with average-risk medulloblastoma
		Zhen Zijun^*,Lu Suying,Xia Yunfei,Wu Shaoxiong,Wang Jian,Zhu Jia,Wang Juan,Yang Qunying,Sun Xiaofei
		Objective To retrospectively analyze the impacts of a craniospinal radiation dose ≤24 Gy or>24 Gy on the prognosis of patients with average-risk medulloblastoma. Methods Average-risk medulloblastoma was defined as non-metastatic cancer in children more than 3 years old with complete or near-complete (residual tumor ≤1.5 cm³) resection of tumor. A total of 72 children and adolescents with newly diagnosed average-risk medulloblastoma were enrolled as subjects from 2003 to 2013. After radical resection of the tumor, all patients received craniospinal plus local tumor bed radiotherapy and 8 cycles of adjuvant chemotherapy using cisplatin-, semustine-, or plus vincristine-based regimens. Patients exposed to a radiation dose ≤24 Gy were enrolled into Group A (n=20), while patients exposed to a radiation dose>24 Gy were enrolled into Group B (n=52). The recurrence rate and survival rate were compared between the two groups. The recurrence rate and survival rate were calculated using the Kaplan-Meier method and the differences between the two groups were analyzed using the log-rank test. ResultsPatients in Group A and Group B received craniospinal radiotherapy with a dose of 19.2-24.0 Gy and 24.1-30.6 Gy, respectively. After radiotherapy, 66 patients (92%) completed all adjuvant chemotherapy. A total of 11 patients were recurrence. In all patients, the 3-year sample size was 48;the 3-year event-free survival (EFS) and overall survival (OS) rates were 83% and 86%, respectively. There were no significant differences in the 3-year EFS and OS rates between Group A and Group B (84% vs. 83%, P=0.609;85% vs. 87%, P=0.963). Conclusions The standard comprehensive therapy achieves satisfactory treatment outcomes for average-risk medulloblastoma, in which a craniospinal radiation dose decreased to 19.2-24.0 Gy has no impacts on treatment outcomes.
		2015 Vol. 24 (5): 540-543 [Abstract] ( 3347 ) [HTML 1KB] [ PDF 464KB] ( 0 )

Physics·Biology·Technique

	538


		2015 Vol. 24 (5): 538-539 [Abstract] ( 2596 ) [HTML 1KB] [ PDF 931KB] ( 0 )

	552	Comparison of difference registration landmarks for image-guided radiotherapy for lung cancer
		Zhang Yanxin, Hui Zhouguang,Li Minghui, Zhang Zhong,Fu Guishan,Dai Jianrong
		Objective To investigate the impact of anatomical landmarks on registration in image-guided radiotherapy (IGRT) for central and peripheral lung cancer. Methods Twenty-five patients with central or peripheral lung cancer for IGRT were enrolled in this study. Kilo-voltage cone-beam CT (kV-CBCT) scanning was acquired before irradiotion. Tumor coverage on CBCT was assessed using gross tumor volume (GTV), clinical target volume (CTV), and planning target volume (PTV) contours according to tumor alignment, carina registration, and spine registration, respectively. The grading analysiswas based on visual tumor assessment as follows:grade 0, tumor within GTV;grade 1, tumor outside GTV but inside CTV;grade 2, tumor outside CTV but inside PTV;and grade 3, tumor outside PTV. Results Totally 177 sets of kV-CBCT of 25 patients was collected. According to the registration landmarks of the tumor, carina and spine for central lung cancer, the percentages were 57.55%, 53.77% and 16.04% in grade 0, 39.62%, 45.28% and 58.49% in grade 1, and 1.89%, 0.94% and 25.47% in grade 2, respectively. For peripheral lung cancer, the percentages were 47.89%, 14.08% and 2.82% in grade 0, 43.66%, 29.58% and 45.07% in grade 1, and 8.45%, 40.85% and 35.21% in grade 2, respectively. Conclusions For central lung cancer,the tumor was recommended as the best registration landmark, and the carina was recommended as well, while the spine was not recommended. For peripheral lung cancer, the tumor was recommended as the best registration landmark, while the spine and the carina were not recommended.
		2015 Vol. 24 (5): 552-555 [Abstract] ( 2872 ) [HTML 1KB] [ PDF 849KB] ( 0 )

	556	Comparison of internal tumor volume based on different reconstruction modes of 4DCT for solitary pulmonary lesion
		Shang Dongping, Ling Minghuan, Li Yanchi,Wu Xianbao,Yin Yong
		Objective To explore the influence of different reconstruction modes with time-weighted respiratory phases on the internal tumor volume (ITV) of solitary pulmonary lesion (SPL), and to evaluate the feasibilities of 8 and 4 equal time-weighted respiratory phases in 4DCT simulation. Methods 24 patients with SPL underwent 4D scanning. Images were reconstructed with 10, 8 and 4 equal time-weighted phases of the respiratory cycles, respectively. Gross tumor volumes (GTVs) were delineated on the three sets of reconstructed images and fused into ITVs, which were ITV₁₀, ITV₈ and ITV₄ respectively. The differences of volumes, centroid of the ITVs and motions of GTV centroids in three-dimensional directions were compared. Statistical analysis was performed using the Friedman M test. Results The volumes of ITV₁₀, ITV₈ and ITV₄ were (9.09±12.29) cm³,(9.10±12.47) cm³ and (8.98±12.61) cm³(P=0.001), respectively. There were no differences between the volumes of ITV₁₀ and ITV₈ after the Bonferroni correction (P=0.721), while the opposite between those of ITV₁₀ and ITV₄(P=0.002). The differences of centroid positions of ITV₁₀, ITV₈ and ITV₄ in x-, y-and z-axes were all less than 1 mm ((12.22±7.71),(12.23±7.71),(12.22±7.71),P_x=0.668);(43.30±29.38),(43.30±29.40),(43.31±29.39),P_y=0.643;(5.66±3.67),(5.66±3.67),(5.66±3.67),P_z=0.878), similar to the motions of GTV centroids in three reconstructed modes ((0.69±0.56),(0.69±0.68),(0.79±0.51) mm,P_x=0.356;(3.13±3.78),(3.13±4.05),(3.19±4.06) mm,P_y=0.978;(1.18±1.31),(1.03±1.32),(1.16±1.34) mm,P_z=0.302). Conclusions There were no differences in volumes, centroid positions and motions between ITV₁₀ and ITV₈. The quantity of reconstruction images and GTV delineations according to 8 time-weighted phases were both less than conventional 10 phases. 8 time-weighted respiratory phases mode was feasible in 4DCT simulation for SPL.
		2015 Vol. 24 (5): 556-559 [Abstract] ( 3264 ) [HTML 1KB] [ PDF 551KB] ( 0 )

	560	Application of ExacTrac and cone-beam computed tomography image-guided radiotherapy in intensity-modulated radiotherapy for lung cancer
		Gao Xufeng,Tang Dewen,Wang Pei,Jiang Cong,Wu Dequan,Zhang Dekang
		Objective To compare set-up error and the positioning and error correction time between the infrared markers automatic positioning+ ExacTrac (A) and the manual positioning+ cone-beam computed tomography (CBCT) image-guided radiotherapy (IGRT)(B) in intensity-modulated radiotherapy (IMRT) for lung cancer. Methods A total of 20 patients with lung cancer were randomly divided into Group A and Group B. In Group A, after automatic positioning, a group of orthogonal X-rays images were taken using kV X-rays, which matched digitally reconstructed radiographs to obtain errors before correction. In group B, after manual positioning, images were taken using CBCT, which matched reference computed tomography images to obtain errors before correction. The positioning and error correction time was recorded in both groups. After error correction, errors after correction were obtained in each group using IGRT. Between-group comparison was made using the paired t test. Results The errors in lateral, longitudinal, vertical, and spinning vertical directions were significantly reduced after correction in both Group A and B (A:1.8±1.3 vs. 0.4±0.1, P=0.000;2.7±1.9 vs. 0.5±0.1, P=0.000;2.8±1.7 vs. 0.4±0.1, P=0.000;1.6±1.0 vs. 0.3±0.9, P=0.000;B:2.6±1.9 vs. 0.5±0.5, P=0.000;3.1±2.5 vs. 0.6±0.6, P=0.000;2.1±1.8 vs. 0.5±0.5, P=0.000;0.9±0.7 vs. 0.3±0.1, P=0.000). There were no significant differences in errors after correction between Group A and Group B (0.4±0.1 vs. 0.5±0.5, P=0.204;0.5±0.1 vs. 0.6±0.6, P=0.257;0.4±0.1 vs. 0.5±0.5, P=0.518;0.3±0.9 vs. 0.3±0.1, P=0.755). However, the positioning and error correction time in Group A was significantly shorter than that in Group B (199.1±16.2 vs. 315.2±13.7, P=0.000). Conclusions The application of ExacTrac or CBCT IGRT can substantially reduce set-up errors and improve set-up accuracy in IMRT. In addition, the application of the ExacTrac system can substantially shorten the positioning and error correction time.
		2015 Vol. 24 (5): 560-563 [Abstract] ( 2454 ) [HTML 1KB] [ PDF 1058KB] ( 0 )

	564	Comparison of planning parameter selection for volumetric modulated arc therapy of nasopharyngeal carcinoma in two different treatment planning systems
		Ma Yan^*,Zheng Jian,Deng Xiaowu,Huang Shaomin,Chen Li
		Objective To investigate the impact of planning parameter settings on plan quality and delivery efficiency of VMAT for nasopharyngeal carcinoma with two treatment planning systems (TPS),as references for clinic plan optimization. Methods 25 patients with nasopharyngeal carcinoma were selected and planned for SIB-VMAT treatment. The same planning aims were used in the two kinds of TPS (TPS-1 and TPS-2).Multiple planning parameters were set for plan optimization. Dose distribution to the target volumes and organs at risk,monitor unit (MU) and delivery time were compared. Paired t-test or one-way ANOVA was used for the data which was in accordance to normal distribution;otherwise,nonparametric Wilcoxon signed rank test or nonparametric Friedman test was used. Results More segments lead to better plan quality and less MU but longer delivery time (Minor impact was observed when segment number was larger than 120) in TPS-1,while it had little impact on both plan quality and delivery efficiency in TPS-2.Comparing to single-arc plans,dual-arc VMAT achieved no significant benefit in plan quality but had more MU and longer delivery time in TPS-1(P=0.000).However,dual-arc VMAT plans had better dose distribution in TPS-2,decreased the maximum and mean dose for spinal cord in 3.9% and 13.7% respectively (P=0.000,0.000).Changing the settings of maximum or minimum dose rate did not affect the plan quality in both of the tested TPSs. Increasing the maximum or minimum dose rate reduced the delivery time but the latter increased the number of MU (P=0.000,0.000). Conclusions VMAT plan quality and delivery efficiency is affected significantly and differently by planning parameter settings for two TPSs. Trial test should be conducted for different TPS to determine the optimal parameter settings.
		2015 Vol. 24 (5): 564-568 [Abstract] ( 2863 ) [HTML 1KB] [ PDF 344KB] ( 0 )

	569	Dosimetric analysis of computed tomography guided three-dimensional intracavitray brachytherapy in endometrial carcinoma
		Yu Lang, Zhang Yu, Sun Xiansong, Wang Xinhai, Yan Junfang, Yang Bo, Qiu Jie
		Objective To study the dosimetric peculiarity of 3D intracavitary brachytherapy in the application of endometrial carcinoma comparing with traditional 2D plans. Method 39 3D brachytherapy treatment plans of 11 patients with endometrial carcinoma were retrospectively analyzed with re-planning 2D treatment plan, the dose volume histogram (DVH) parameters such as the target dose volume parameters V₁₅₀ and D₉₀, the 2-cc doses to organs such as bladder,small intestine,rectum and sigmoid and the total reference air kerma TRAK were analyzed. The differences between the two groups are compared by paired samples T test. Results For target with V<60 cm³,there is no statistically significant difference between 2D and 3D plans,the D₉₀ is (551.17±90.33) cGy and (574.15±117.18) cGy,respectively (P=0.390). As the increase of target volume,the D₉₀ came to be significantly different (P=0.001), high dose region V₁₅₀ for 3D and 2D plans is (51.05±21.61) cm³ and (53.41±11.71) cm³, respectively (P=0.482). With the target volume larger than 60 cm³,compare to 2D plans, the 3D plan can increase the target coverage as well as OAR dose except for small intestine (P=0.128). In addition, with different plan mode,the BMI did not affect the crisis organ dose such as rectum,small intestine, bladder and sigmoid,the P value is 0.239,0.198,0.744 and 0.834,respectively. Conclusions For endometrial carcinoma,compared with traditional two-dimensional plans,the 3D brachytherapy treatment plans can significantly improve the target coverage and avoiding overdose of organs, clinical curative effect and side effect still needs further observation.
		2015 Vol. 24 (5): 569-572 [Abstract] ( 3376 ) [HTML 1KB] [ PDF 382KB] ( 0 )

	573	The study of electronic portal imaging devices for the position accuracy of multi-leaf collimator instead of the film
		Cao Zheng^*, Li Hongxia, Bao Yangyi, Hong Dexiong
		Objective To explore the application of the electronic portal imaging device (EPID) to test on MLC leaves position accuracy instead of EBT3 film, and the feasibility analysis under any gantry angle. Methods RIT113 software was used to analyze the image data of radiochromic film EBT3 and EPID of Siemens ARTISTE accelerator. The replacement process from EBT3 film to EPID for the test MLC leaves positioning was completed by defining the positions of 50% isodose curve of the field edge of EBT3 after radiation as the actual positions of MLC leaves, therefore finding out the percentage isodose value of the same position in the EPID portal imaging from the corresponding radiation field. Results When the accelerator gantry angle was 0, the mean percentage isodose value was 44% at the MLC leaves positions determined by EBT3, and the maximum position error of MLC leaves is 0.12 mm. When the accelerator gantry was any other angles, the results were compared with the zero angle situation through DTA, all of the points passed when the DTA radium was 0.5 mm. Conclusions Using EPID instead of EBT3 to do the test MLC leaves positioning is feasible, furthermore, it is suitable under any gantry angle with excellent accuracy for the clinical practive, which deserves to be widely spread.
		2015 Vol. 24 (5): 573-574 [Abstract] ( 3132 ) [HTML 1KB] [ PDF 1077KB] ( 0 )

	581	Image registration of a three-dimensional dynamic phantom in four-dimensional cone-beam computed tomography and four-dimensional computed tomography
		Su Chen,Bai Sen,Li Guangjun,Zhang Yingjie,Zhong Renming,Xu Feng,Li Yanlong,Wang Xuetao
		Objective To evaluate the image quality and registration accuracy of a three-dimensional (3D) dynamic phantom in four-dimensional computed tomography (4DCT) and four-dimensional cone-beam computed tomography (4DCBCT). Methods The Computerized Imaging Reference Systems Dynamic Thorax Phantom Model 008A was scanned to get 4DCT and 4DCBCT images. Two balls with different diameters (= 1 cm and = 2 cm) were used to simulate tumors with different sizes. The motion mode of the balls was 3D sinusoidal motion at 0.25 Hz (the amplitudes along the x, y, and z axes were ±1.0 cm, ±0.4 cm, and ±0.2 cm, respectively). Gross target volumes (GTVs) from 10-phase bins, internal gross target volumes (IGTV), and target volumes on maximum intensity projection (MIP) and mean intensity projection (MeanIP) images were contoured and calculated. Target volumes on 4DCT or 4DCBCT images were compared with the static and dynamic volumes of the balls (V_S and V_D). The matching index (MI) of target volumes between the 4DCT and 4DCBCT images was analyzed after rigid image registration. Results The GTV in each phase of the image was larger than V_S. The difference between the average GTV derived from 10 phases of 4DCT or 4DCBCT images and Vs of the small ball was larger than that of the large ball (35.03% vs. 22.66%;32.62% vs. 17.00%). All the IGTVs and target volumes on MIP images were slightly larger than V_D, but target volumes on MeanIP images were smaller than V_D. The average MI of 10-phase bins of the small ball was smaller than that of the large ball (66.76% vs. 82.21%). Moreover, MIs of IGTV,MIP, and MeanIP of the small ball were also smaller than those of the large ball (77.39% vs. 90.29%;75.90% vs. 89.28%;74.47% vs. 82.74%). Conclusions In the case of a relatively small tumor volume and a relatively large motion amplitude, 4DCT and 4DCBCT should be used with caution for comparison of image registration.
		2015 Vol. 24 (5): 581-584 [Abstract] ( 3947 ) [HTML 1KB] [ PDF 527KB] ( 0 )

	585	Impacts of applicators on ¹⁹²Ir brachytherapy dosimetry
		Wang Xianliang, Kang Shengwei, Li Jie, Wang Pei,Tan Yan
		Objective To study the impacts of different applicators on dose distribution in ¹⁹²Ir brachytherapy. Methods The inner tubes of two cylinder applicators from Nucletron,#101.001 and#084.350, were made of plastic and stainless steel, respectively. The cylinder parts of them were made of plastic, and had four different radiuses:1.00 cm, 1.25 cm, 1.50 cm, and 1.75 cm. EGSnrc program was used to simulate dose distribution when applicators were present in a phantom, and the results calculated by the treatment planning system were compared with the results of EGSnrc. The impacts of applicators on dosedistribution were analyzed with different materials, thickness, and numbers of resident source. ResultsThere was no significant relationship between dose deviation and the radius for the two applicators. When an applicator was present, the actual dose delivered to a patient was smaller than the planned dose. The dose deviation of the applicator#101.001 was no more than 1%, while the dose deviation of the applicator#084.350 was close to 3%. The dose deviation remained the same when the number of resident source changed. Conclusions The plastic applicator, if possible, is the best choice for brachytherapy right now. In a long term, in order to promote the accuracy of brachytherapy, current dosimetry algorithm should be improved, and the impacts of the applicator made of metal, such as stainless steel, on dose distribution should be taken into account.
		2015 Vol. 24 (5): 585-587 [Abstract] ( 2945 ) [HTML 1KB] [ PDF 1889KB] ( 0 )

	588	Radiosensitizing effect of ARQ197, a small-molecule tyrosine kinase inhibitor of c-Met, on lung cancer cell line H1299
		Shan Fang^*, Zhang Jingdi,Chen Liesong,Chen Yongbing,Lu Xueguan
		Objective To evaluate the radiosensitizing effect and action mechanism of a tyrosine kinase inhibitor, ARQ197, on lung cancer cell line H1299. Methods H1299 cells were treated with different concentrations of recombinant human hepatocyte growth factor (HGF) and ARQ197, respectively. Colony formation assay was used to investigate the proliferation of H1299 cells, and the optimal concentrations of HGF and ARQ197 were figured out for the radiosensitivity study. H1299 cells were divided into control, HGF-treated, ARQ197-treated, and HGF+ARQ197-treated groups, and the differences between those groups were evaluated. The impacts of HGF, radiation alone, or HGF+ARQ197 on the expression and activation of c-Met and the downstream Akt and Erk1/2 were determined by Western blot. Results The colony formation rate of H1299 cells increased with increasing HGF concentration, and decreased with increasing ARQ197 concentration. Using the linear-quadratic model, the cell survival curve showed that the radiation dose enhancement ratios for H1299 cells treated with HGF, HGF+ARQ197, and ARQ197 were 0.85, 1.20, and 1.27, respectively, when the surviving fraction was 0.1. The expression of pc-Met, p-Akt, and p-Erk1/2 proteins increased in H1299 cells after HGF stimulation. In HGF+ARQ197-treated cells, the expression of pc-Met, p-Akt, and p-Erk1/2 proteins decreased with increasing ARQ197 concentration. After 2 Gy irradiation, the expression of pc-Met, p-Akt, and p-Erk1/2 proteins increased in HGF-treated cells but substantially decreased in HGF+ARQ197-treated cells, while there were no significant changes in the expression of total c-Met, Akt, and Erk1/2 proteins. Conclusions ARQ197 has a substantial radiosensitizing effect on lung cancer cell line H1299 in vitro by inhibiting HGF/c-Met and activation of downstream signaling pathways.
		2015 Vol. 24 (5): 588-592 [Abstract] ( 3006 ) [HTML 1KB] [ PDF 738KB] ( 0 )

	593	Impacts of endostatin on expression of vascular endothelial growth factor receptor-2 in non-small cell lung cancer cells and mechanisms underlying its radiosensitizing effect
		Liu Liang^*,Liu Yi,Xia Youyou,Hu Chenxi,Qiao Yun,Wang Lei,Liu Bin,Chen Hui,Jiang Xiaodong
		Objective To determine the effects of endostatin on the expression of vascular endothelial growth factor receptor-2(VEGFR-2) in non-small cell lung cancer cells (human A549 lung adenocarcinoma cells and human Calu-1 lung carcinoma cells), and to investigate the possible mechanisms underlying its radiosensitizing effect. Methods The CCK8 method was used to determine the inhibitory effect of endostatin on cell proliferation and calculate the drug concentration that caused a 20% reduction in cell proliferation within 24 h (IC₂₀). RT-PCR and Western blot assays were used to assess the mRNA and protein expression of VEGFR-2, proteins within its related signaling pathways, and HIF-1α, respectively. The radiosensitivity of cells in each group was determined by colony formation assay;cell apoptosis and cell cycle distribution were determined by flow cytometry. Comparison of mean values between multiple samples was made by one-way analysis of variance, and comparison of mean values between two samples was made by t test. Results Endostatin significantly inhibited the proliferation of Calu-1 cells (F=50.36,P<0.01) with an IC₂₀ of 296.5 μg/ml;the mRNA and protein expression of VEGFR-2 and HIF-1α was also significantly inhibited in endostatin-treated Calu-1 cells (F=25.43,10.44, all P<0.05). Moreover, the phosphorylation of Akt, ERK1/2, and p38 was significantly reduced in endostatin-treated Calu-1 cells (F=2.89,0.24,1.09, all P<0.05). The radiosensitivity enhancement ratios for Calu-1 cells and A549 cells were 1.38 and 1.09, respectively. Endostatin significantly induced apoptosis (F=44.15, P<0.01) and G₂/M blockage (F=104.24,P<0.01) in Calu-1 cells. Conclusions Endostatin induces apoptosis and enhances radiosensitivity in Calu-1 cells with high expression of VEGFR-2, but it has a limited impact on A549 cells with low expression of VEGFR-2.
		2015 Vol. 24 (5): 593-597 [Abstract] ( 3082 ) [HTML 1KB] [ PDF 945KB] ( 0 )

	598


		2015 Vol. 24 (5): 598-600 [Abstract] ( 2386 ) [HTML 1KB] [ PDF 1037KB] ( 0 )

	548


		2015 Vol. 24 (5): 548-551 [Abstract] ( 2340 ) [HTML 1KB] [ PDF 2409KB] ( 0 )

Review

	575


		2015 Vol. 24 (5): 575-580 [Abstract] ( 3020 ) [HTML 1KB] [ PDF 0KB] ( 0 )

	600


		2015 Vol. 24 (5): 600-604 [Abstract] ( 3137 ) [HTML 1KB] [ PDF 353KB] ( 0 )

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