中低位局部进展期直肠癌新辅助放化疗后肿瘤消退分级的预测因素研究

Predictive factors of tumor regression grading after neoadjuvant chemoradiotheraphy in locally advanced rectal cancer

目的探讨中低位局部进展期直肠癌新辅助放化疗后肿瘤消退分级（TRG）的预测因素。方法分析68例接受术前新辅助放化疗的中低位局部进展期直肠癌患者临床病理资料，以TRG作为放化疗后敏感性的判断指标，分析临床和分子生物学指标与新辅助放化疗敏感性的关系。结果TRG 0级者3例（4.4%），TRG 1级者14例（20.1%），TRG 2级者30例（44.1%），TRG 3级者13例（19.1 %），TRG 4级者8例（11.8%）。单因素分析结果显示，放化疗前T3（P＝0.008）、放化疗前cN0（P＝0.000）、K-ras基因野生型（P＝0.007）与新辅助放化疗后的TRG高分级有关。多因素回归分析结果显示，放疗前T分期、N分期、K-ras基因型是影响TRG分级的预测因素。结论放疗前早T分期、淋巴结阴性、K-ras基因野生型可能是局部进展期直肠癌新辅助放化疗后高敏感性的预测因素。

Objective To explore the predictive factors of tumor regression grading （TRG） after neoadjuvant chemoradiotheraphy of patients with locally advanced rectal cancer.Methods A retrospective analysis was performed on clinical and molecular biological data of 68 patients with rectal cancer, who underwent neoadjunant chemoradiotheraphy followed by radical surgery from April 2007 to December 2016. The clinical factors associated with TRG were analyzed by Logistic regression.Results Overall, there were 3 cases of TRG 0 （4.4%）, 14 cases of TRG 1 （20.1%）, 30 cases of TRG 2 （44.1%）, 13 cases of TRG 3 （19.1 %）, and 8 cases of TRG 4 （11.8%）. Univariate analysis showed pre-neoadjuvant chemoradiotheraphy stage cT3 （P=0.008）, cN0 （P=0.000）, and the K-ras mutation status of wide-type （P=0.007） were significantly correlated with TRG after neoadjuvant chemoradiotheraphy. Logistic regression revealed that cT, cN and K-ras were independent predictive factors of TRG after neoadjuvant chemoradiotheraphy in rectal cancer.Conclusion Early stage of T and N, and the K-ras mutation status of wide-type may be predictive factors of high degree of TRG for rectal cancer after neoadjuvant chemoradiotherapy.