Abstract：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.
Wang Lan,Liu Lihong,Han Chun et al. A comparative study of computed tomography and magnetic resonance imaging in pathological diagnosis of regional lymph node metastasis[J]. Chinese Journal of Radiation Oncology, 2015, 24(5): 493-496.
[1] Lau CL, Harpole DH. Noninvasive clinical staging modalities for lung cancer[J]. Semin Surg Oncol,2000,18(2):116-123. [2] Gallardo J, Naranjao F, Cansino M, et al. Validity of enlarged mediastinal nodes as markers of involvement by non-small cell lung cancer[J]. Am Respir Dis,1992,146(5):1210-1212. [3] Nakayama J, Miyasaka K, Omatsu T, et al. Metastases in mediastinal and hilar lymph nodes in patients with non-small cell lung cancer:quantitative assessment with diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient[J]. J Comput Assist Tomogr,2010,34(1):1-8.DOI:10.1097/RCT.0b013e3181a9cc07. [4] Alper F, Turkyilmaz A, Kurtcan S, et al. Effectiveness of the STIR turbo spin-echo sequence MR imaging in evaluation of lymphadenopathy in esophageal cancer[J]. Eur J Radiol,2011,80(3):625-628.DOI:10.1016/j.ejrad.2010.08.003. [5] 徐烨,申屠阳,郑敏,等.肺癌术前常规纵隔淋巴结外科分期的临床价值[J].中国肺癌杂志,2010,13(6):624-627.DOI:10.3779/j.issn.1009-3419.2010.06.011. [6] Nomori H, Mori T, Ikeda K, et al. Diffusion-weighted magnetic resonance imaging can be used in place of positron emission tomography for N staging of non-small cell lung cancer with fewer false-positive results[J]. J Thorac Cardiovasc Surg,2008,135(4):816-822.DOI:10.1016/j.jtcvs.2007.10.035. [7] Hasegawa I, Boiselle PM, Kuwabara K, et al. Mediastinal Lymph nodes in patients with non-small cell lung cancer:preliminary experience with diffusion-weighted MR imaging[J]. J Thorac Imaging,2008,23(3):157-161.DOI:10.1097/RTI.0b013e318166 d2f5. [8] 贺伟,周新华,贺文,等.磁共振弥散加权成像诊断肺癌淋巴结转移[J].中国医学影像技术,2011,27(10):2013-2016. [9] Edge SB, Compton CC. The American Joint Committee on Cancer:the 7th edition of the AJCC cancer staging manual and the future of TNM[J]. Ann Surg Oncol,2010,17(6):1471-1474.DOI:10.1245/s10434-010-0985-4. [10] Kerr KM, Lamb D, Wathen CG, et al. Pathological assessment of mediastinal lymph nodes in lung cancer:implication for noninvasive mediastinal staging[J]. Thorax,1992,47(5):337-341. [11] 刘林,蒋仁超,王卓才,等.非小细胞肺癌淋巴结大小与转移的关系[J].中国肿瘤临床,2004,31(16):931-933. [12] 杨衿记,吴一龙,颜杰,等.18FDG-PET与CT诊断非小细胞肺癌纵隔淋巴结转移的对比研究——一项基于SROC的1999—2002年文献的Meta分析[J].循证医学,2003,3(3):132-141. [13] 张倩倩,徐亮,申洪明,等.CT及DWI评价食管癌术前淋巴结转移及N分期对比研究[J].实用放射学杂志,2013,29(7):1075-1078.DOI:10.3969/j.issn.1002-1671.2013.07.012.
2015, Vol. 24 
