直肠癌术前个体化同步放化疗敏感性研究

目的探讨中低位局部进展期直肠癌术前同步放化疗敏感性的预测因素，以指导直肠癌的个体化治疗。方法回顾性分析中南大学湘雅医院2006年8月至2012年9月间收治的44例中低位局部进展期直肠癌患者的临床病理资料，采用免疫组织化学方法检测放化疗前直肠癌组织中表皮生长因子受体（EGFR）的表达，以放化疗后肿瘤TNM分期降期与否和肿瘤消退程度（TRG分级）作为同步放化疗敏感性的判断标准，分析放化疗前患者临床病理及分子生物学特征与同步放化疗敏感性的关系。结果癌组织EGFR阴性或弱阳性表达者肿瘤降期86．7％（13／15）]和TRG为3—4级的比例80．0％（12／15）]明显高于强阳性或中度阳性表达者30．4％（7／23）和8．7％（2／23）]，差异有统计学意义（P〈0．01）。管状腺癌者肿瘤降期61．8％（21／34）]和TRG为3-4级的比例47．1％（16／34）]明显高于黏液腺癌者10．0％（1／10）和0]，差异有统计学意义（P〈0．01）；EGFR表达与肿瘤的病理类型无关（P〉0．05）。患者年龄、性别、肿瘤分期、肿瘤分化程度、血清CEA、血清CA199及放疗方式与同步放化疗敏感性无明显关联（均P〉0．05）。结论EGFR表达和病理类型可能是直肠癌术前同步放化疗敏感性预测的两个独立指标，管状腺癌和EGFR低表达患者对同步放化疗更为敏感。

Sensitivity study on preoperative individual concomitant radiochemotherapy for rectal cancer

Objective To explore the predictive factors of sensitivity to preoperative concomitant radioehemotherapy for the local mid-low advanced rectal cancer in order to guide the individualized therapy. Methods Clinicopathologic data of 44 patients with local mid-low advanced rectal cancer receiving preoperational concomitant radiochemotherapy were retrospectively analyzed. Expression of epidemical growth factor receptor （EGFR） in biopsy specimen was detected with SP immunohistochemisty （IHC）. Downstaging of tumor TNM stage and tumor regression grade （TRG） after radiochemotherapy were used as the standards of sensitivity to preoperational concomitant radiochemotherapy. Association of EGFR expression and pathological change with clinicopathological data before radiochemotherapy （gender, age, pathological type, tumor TNM stage, serum CEA, CA199, radiation method, etc） was analyzed. Results Percentage of downstaging of tumor TNM stage and 3-4 TRG in patients with negative or weak positive EGFR expression was significantly higher as compared to those with strong and moderate positive EGFR expression 86.7% （13/15） vs. 30.4% （7/23）, P〈0.01; 80.0% （12/15） vs. 8.7% （2/23）, P〈0.01]. Percentage of downstaging of tumor TNM stage and 3-4 TRG in patients with tubular adenocarcinoma was significantly higher as compared to those with mucous adenocarcinoma 61.8%（21/34） vs. 10.0% （1/10）, P〈0.01; 47.1 （16/34） vs. 0 （0/10）, P〈0.01]. EGFR expression was not associated with pathological type （P〉0.05）. Sensitivity to preoperative concomitant radioehemotherapy was not associated with age, gender, tumor stage, tumor differentiation, serum CEA, serum CA199 and radiation method （all P〉0.05）. Conclusions Pathological type and EGFR expression level may be two independent predictive markers of sensitivity to preoperative concomitant radiochemotherapy for patients with rectal cancer. Patients with tubular adenoearcinoma or low EGFR expression in tumor tissue may be more sensitive to concomitant radiochemotherapy.