直肠癌原发肿瘤消退分级与淋巴结消退分级关系的研究

Study on the relationship between tumor regression grade and lymph node regression grade

目的探讨直肠癌新辅助放化疗后原发肿瘤消退分级与淋巴结消退分级的关系及其临床意义。方法回顾性分析2005—2013年间在第二军医大学附属长海医院肛肠外科接受新辅助放化疗和根治性手术治疗的176例直肠癌患者的临床病理资料，病例纳入标准：（1）放化疗前影像学检查提示局部晚期或肿瘤位置低而保肛意愿强烈的直肠癌患者；（2）放化疗前未见明确转移病灶；（3）接受全程新辅助放化疗（常规放疗加氟尿嘧啶类药物同步化疗；（4）放化疗结束后接受根治性手术。排除接受短程放疗和行急诊手术者。根据肿瘤纤维化程度和残余肿瘤百分比对术后标本（包括肿瘤灶和淋巴结）进行原发肿瘤消退分级（TRG）和淋巴结消退分级（LRG），TRG 1和LRG 1，表示没有肿瘤残留；TRG 2和LRG 2，散在肿瘤细胞残留；TRG 3和LRG 3，纤维化组织超过残留肿瘤组织；TRG 4和LRG 4，残留肿瘤组织超过纤维化组织；TRG 5和LRG 5，肿瘤无明显消退；而正常淋巴结以LRG 0表示。Spearman秩相关检验分析TRG与LRG之间的相关性。结果176例直肠癌患者中男性111例，女性65例，年龄（53.9 ± 13.0）岁；肿瘤TNM分期：Ⅰ期10例，Ⅱ期49例，Ⅲ期62例，另有55例术前分期不明。经腹低位前切除术（LAR）118例，经腹会阴联合切除术（APR）47例；均遵循全直肠系膜切除原则。术后病理示，19例（10.8%）TRG 1，25例（14.2%）TRG 2，66例（37.5%）TRG 3，47例（26.7%）TRG 4，19例（10.8%）TRG 5；35例（19.9%）LRG 0，68例（38.6%）LRG 1，10例（5.7%）LRG 2，14例（8.0%）LRG 3，15例（8.5%）LRG 4，34例（19.3%）LRG 5。TRG与LRG存在相关性（P= 0.005），但相关系数仅为0.24；除外LRG 1的亚组分析同样显示，TRG与LRG存在相关性（P= 0.005），相关系数为0.40。结论原发肿瘤消退分级并不能反映淋巴结消退分级，在评价直肠癌新辅助放化疗反应时，需对原发肿瘤和淋巴结分别进行评估。

ObjectiveTo investigate the relationship between tumor regression grade （TRG） and lymph node regression grade （LRG） after neoadjuvant chemoradiotherapy （CRT） for rectal cancer and its clinical implication.MethodsClinicopathological data of 176 rectal cancer patients undergoing radical excision after neoadjuvant CRT from January 2005 to December 2013 in our department were retrospectively analyzed. Inclusion criteria： （1） Radiology indicated locally advanced low rectal cancer and patients had strong desire to preserve the sphincter before neoadjuvant CRT; （2） there was no definite metastatic lesion before neoadjuvant CRT; （3） patients received whole course of neoadjuvant CRT （regular radiotherapy plus synchronous fluorouracil-like drugs chemotherapy） ; （4） patients underwent radical operation after neoadjuvant CRT. Patients with short-course CRT and emergency surgery were excluded. TRG and LRG of postoperative specimens （including tumor and lymph nodes） were carried out based on the percentage of the fibrosis and the cancer residue. No cancer residue was defined as TRG1 and LRG1; rare cancer cell residue as TRG2 and LRG2; fibrosis growth over residual cancer as TRG3 and LRG3; residual cancer growth over fibrosis as TRG4 and LRG4; absence of regressive changes as TRG5 and LRG5; and normal lymph nodes as LRG0. Spearman correlation test was used to assess the correlation between TRG and LRG.ResultsOf 176 patients, 111 were men and 65 were women. The mean age was （53.9 ± 13.0） years. The number of patients with stage Ⅰ, Ⅱ, and Ⅲ before operation was 10, 49 and 62 while other 55 patients were unknown. Transabdominal low anterior resection （LAR） was performed in 118 cases and abdominal-perineal resection （APR） in 47 cases following the principle of total mesorectal excision （TME） . Postoperative pathology of specimens revealed that the number of patients from TRG1 to TRG5 was 19 （10.8%） , 25 （14.2%） , 66 （37.5%） , 47 （26.7%） , 19 （10.8%） , and from LRG0 to LRG5 was 35 （19.9%） , 68 （38.6%） , 10 （5.7%） , 14 （8.0%） , 15 （8.5%） , 34 （19.3%） , respectively. TRG was correlated to LRG （P= 0.005） while the Spearman correlation coefficient was only 0.24. The analysis of subgroup without LRG1 also showed that TRG was correlated to LRG （P= 0.0005） and the Spearman correlation coefficient was 0.40.ConclusionsTRG can not represent LRG. Therefore, both TRG and LRG should be assessed when evaluating the response of rectal cancer to neoadjuvant CRT.