新辅助放化疗对直肠癌细胞生物学特性的影响及临床意义

Impact of neoadjuvant chemoradiotherapy on the biological characteristics of rectal cancer cells and clinical significance

目的观察新辅助放化疗对直肠癌细胞凋亡、增殖以及侵袭能力的影响。方法选取本院42例中低位局部进展期直肠癌患者为研究对象，应用免疫组织化学法检测新辅助同步放化疗前、后直肠癌组织中与其生物学特性相关指标癌胚抗原（CEA）、细胞增殖核抗原（Ki-67）、血管内皮生长因子（VEGF）的表达，进行统计学分析和评价并观察新辅助放化疗的临床疗效。结果CEA、Ki-67、VEGF在新辅助治疗前直肠癌组织中的阳性表达率分别为88．09％（37／42）、69．05％（29／42）和66．67％（28／42）；在新辅助治疗后直肠癌组织中的阳性表达率分别为57．14％（24／42）、47．62％（20／42）和42．86％（18／42），两组比较差异有统计学意义（P〈0．05）。57．14％（24／42）的患者肿瘤分期降级，癌灶范围缩小，距肛缘的距离增大。42例患者均行手术治疗，其中33例行低位或超低位前切除术（Dixon术），8例行腹会阴联合切除术（Miles术），1例行Hartmann术，保肛率为78．57％（33／42）。84．85％（28／33）的患者术后肛门括约肌功能良好。结论中低位局部进展期直肠癌采用术前新辅助放化疗能降低癌组织中CEA、Ki-67、VEGF表达，促进直肠癌肿瘤细胞凋亡、抑制直肠癌肿瘤细胞的增殖与转移，降低肿瘤分期、提高手术切除率和保肛成功率。

Objective To provide reliable support for the application of neoadjuvant therapy for advanced rectal cancer by exploring the impacts of the therapy on apoptosis, proliferation, and invasive a- bility of the cancer cells. Methods Forty - two patients with local mid - low advanced rectal cancer were chosen in our hospital from January 2010 to December 2014. The expression of carcinoembryonic antigen （CEA） , proliferation cell nuclear antigen （Ki- 67） , and vascular endothelial growth factor （VEGF） in rectal cancer before and after chemoradiotherapy was detected by immunohistochemistry and statistically an- alyzed. The clinical effectiveness of neoadjuvant therapy was observed. Results The positive expression rate of CEA, Ki - 67, and VEGF in rectal cancer tissue before neoadjuvant chemoradiotherapy was 88.09% （37/42）, 69.05% （29/42）, and 66. 67% （28/42）, and that after neoadjuvant chemoradio- therapy was decreased to 57.14% （24/42）, 47. 62% （20/42）, and 42. 86% （18/42）, respectively （P 〈0. 05）. Of these 42 patients, 24 patients obtained downstaging （57. 14% ）, tumor size decreased while anal distance from edge increased. Thirty- three patients received low/ultralow anterior resection （ Dixon）, and 8 patients received abdominoperineal resection （Miles） 6 - 8 weeks after chemoradiotherapy. The sphincter preservation rate was 78. 57% （33/42）. 84. 85% （28/33） patients showed excellent function of sphincter. Conclusion The preoperative neoadjuvant chemoradiotherapy in the local mid - low advanced rectal cancer patients has shown its efficacy in reducing CEA, Ki - 67, and VEGF expression, promoting the apoptosis of cancer ceils, inhibiting the proliferation and metastasis of rectal cancer ceils, down - staging cancer, enhancing respectability, snf offering sphincter preservation.