Preoperative neoadjuvant therapy has become a hot topic in the treatment of locally advanced esophageal cancer (EC) in recent years. Accumulated evidences have demonstrated that neoadjuvant therapy combined with surgery could significantly improve the survival of patients with locally advanced EC compared with the surgery alone. The importance of neoadjuvant chemotherapy (nCT) and neoadjuvant chemoradiotherapy (nCRT) has been widely recognized and included in the guidelines. For locally advanced EC, especially for esophageal adenocarcinoma, both nCT and nCRT can significantly prolong the survival of patients than the surgery alone. Currently, whether the supplement of radiotherapy can bring more benefits to patients compared with nCT alone remains a hot topic. Besides, it is generally believed that the operation should be performed at 2-8 weeks after neoadjuvant therapy, whereas the optimal time interval remains debated. In this article, the research progress and existing problems in the preoperative neoadjuvant treatment of locally advanced EC were summarized.

Objective To analyze the efficacy and its impacting factors of pelvic confined muscle invasive bladder cancer (MIBC) treated with radiotherapy,also including the preservation of functional bladders and the treatment related late toxicity. Methods Forty-five MIBC patients who received radiotherapy from March 1999 to October 2016 in our hospital were analyzed.41 of the patients were transitional cell carcinomas. The radiation volume included the bladder±pelvic lymph node with or without local tumor boost,with a median bladder dose of 45 Gy and median tumor dose of 56 Gy.24 patients received concurrent chemoradiotherapy.14 patients received neoadjuvant chemotherapy,and 29 underwent transurethral resection of bladder tumors before radiotherapy. Results The median follow-up duration was 28 months (range,4–101 months).The 3-year overall survival were 51%.Concurrent chemoradiotherapy had a better survival than that of radiation alone,with 3-year overall survival of 64% and 30%(P=0.001).The effect of neoadjuvant chemotherapy on 3-year overall survival was not obvious,59% and 47%(P=0.540) with or without neoadjuvant chemotherapy. The 3-year overall survival were 58% and 43%(P=0.160),respectively for patients with or without the transurethral resection of bladder tumors. The 3-year overall survival were 20% and 79%(P=0.001) for patients with or without relapse. Nine patients recurred locally and fourteen patients developed metastases. The highest bowel toxicity of more than 3 months after radiotherapy was grade 2 in 2 patients. Late grade 2 urinary toxicity occurred in 4 patients,grade 3 in 2 patients. All other patients preserved their functional bladders except 7 patients who had an uncontrolled bladder tumors or radiation induced severe injury of bladder function. Conclusions A better survival could be obtained for localized muscle invasive bladder cancer treated with concurrent chemoradiotherapy. Most of the patients can preserve their functional bladders after radiotherapy,and the late toxicity is acceptable.

Objective To evaluate whether the self-designed single-channel intracavitary applicator yields equivalent clinical efficacy and safety to the standard Fletcher-type three-channel applicator in the high-dose-rate (HDR) brachytherapy for uterine cervical cancer. Methods From December 2011 to April 2017,patients initially diagnosed with cervical cancer were randomly assigned into the external beam radiotherapy (EBRT)+ single-channel intracavitary applicator group (the patent single-channel group) and EBRT+the Fletcher applicator group. Whole pelvis irradiation was delivered with 6-MV photons via a four-field box variant or anterior and posterior parallel fields. Five to six fractions of intracavitary brachytherapy were performed at a dose of 7 Gy at point A once a week after 30 Gy (BED at point A:80-90 Gy).Chemotherapy was given with intravenous injection of cisplatin at a dose of 40 mg/m² once weekly during EBRT.Clinical efficacy and safety were evaluated after the treatment. Results In total,150 eligible cases were assigned into the Fletcher applicator group and 149 cases into the patent single-channel group. The short-term clinical efficacy and acute toxicity did not significantly differ between two groups. The response rate was 94.0% in the Fletcher group,and 94.7% in the patent single-channel group. In the Fletcher applicator group,76(50.7%) patients developed ≥ grade 3 hematologic toxicity and 61(40.9%) in the patent group (P=0.195). Conclusions The self-designed patent single-channel intracavitary applicator yields equivalent clinical efficacy and safety (acute toxicity) to the standard Fletcher-type three-channel applicator in the HDR brachytherapy for uterine cervical cancer.Clincal Trial Registration Chinese Clinical Trial Registry (ChiCTR-TRC-12002321).

Objective To investigate the role of p75 neurotrophin receptor (p75NTR) in the irradiation-induced hippocampal neurogenesis impairment. Methods Thirty Sprague-Dawley rats were subject to whole brain irradiation with a single dose of 10 Gy 4 MeV electron beam. At 1 month after irradiation,the hippocampal tissues of the rats were collected. Western blot was used to detect the changes in the expression level of p75NTR protein. Immunofluorescence confocal laser microscopy was performed to observe the variations in the hippocampal neurogenesis. The stereotatic method was adopted for intra-hippocampal injection of AAV-shp75NTR to specifically knock out p75NTR.The relationship between p75NTR and hippocampal neurogenesis was analyzed. Results Western blot demonstrated that the expression of p75NTR protein was significantly up-regulated by 43.8% after irradiation (P<0.05).Immunofluorescent staining showed that the quantity of BrdU⁺NeuN⁺ cells in rats was significantly decreased by 81.5% at 1 month after irradiation compared with that in the control group (P<0.01).After the specific knockout of p75NTR,hippocampal neurogenesis was obviously protected. Conclusions p75NTR plays a pivotal role in the irradiation-induced hippocampal neurogenesis impairment.

Objective To compare the dosimetric parameters of target volumes and organs at risk between volumetric-modulated arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) for left sided breast cancer after breast-conserving surgery by a meta-analysis. Methods Literature search was performed to include related studies to analyze the dosimetric parameters of target volumes and organs at risk. Results A total of 11 studies involving 154 patients were included in meta-analysis. There were no significant differences in Dmean,HI of PTV-Whole breast and PTV-Boost. Comparing to IMRT,VMAT increased the conformity index (CI) of PTV-Whole breast (P=0.000) and PTV-Boost (P=0.002).When the mean volume of target volumes was≤634 cm³,there were no significant differences in Dmean,V5,V20 of the heart and left sided lung,V30 of the heart,Dmean of the right sided lung and breast between VMAT and IMRT.When the mean volume of target volumes was>634 cm³,the Dmean(P=0.037),V5(P=0.005) and V20(P=0.030) of the heart in IMRT was lower than VMAT,but the V30(P=0.001) of heart in VMAT was lower than IMRT.IMRT showed significantly lower Dmean(P=0.013),V5(P=0.000),V20(P=0.000) of the left sided lung,and Dmean(P=0.001) of the right sided lung than VMAT.There were no significant differences in Dmean of the right sided breast. Conclusions There were no significant differences in dosimetric parameters of target volumes between VMAT and IMRT.When the mean volume of target volumes was≤634 cm³,there were no significant differences in dosimetric parameters of organs at risk. When the mean volume of target volumes was>634 cm³,IMRT has some advantages in protection of the heart and lung.

In recent years,the incidence rate of prostate cancer has been gradually elevated year by year in China. External radiotherapy yields similar clinical efficacy to surgery in the treatment of localized prostate cancer. Because the rectum is close to the prostate,the radiotherapy targeting for prostate cancer constantly causes radiation-related proctitis. Recently,multiple researchers have attempted to inject polyethylene glycol hydrogel into the rectal prostate space to separate the rectum from the prostate,thereby reducing the radiation dose coverage for the rectum and minimizing the risk of radiation-related proctitis. In this article,the application basis,radiation stability,injection technology,dosimetry and clinical efficacy of polyethylene glycol hydrogel injection were summarized.