中文摘要：

目的 总结多原发结直肠癌的临床病理特点.方法 回顾性分析2001年1月至2008年3月北京大学人民医院收治的30例多原发结直肠癌和580例单发结直肠癌患者的临床资料,30例多原发结直肠癌患者中同时性多原发癌（SC）16例,异时性多原发癌（MC）14例.计数资料采用x^2检验,生存分析采用Kaplan-Meier法,生存率的比较采用Log-rank检验.结果 MC首发癌发病年龄早于SC和单发结直肠癌,而MC第二原发癌与SC和单发结直肠癌发病年龄接近.SC多位于左半结肠;MC首发癌以直肠、乙状结肠为多,第二原发癌以升结肠为主.SC和MC首发癌均行根治性切除,MC第二原发癌行根治性手术9例.除3例SC患者和2例MC患者未行化疗外,其余患者术后均接受FCF或FOLFOX或XELOX化疗方案治疗.单发结直肠癌患者中行根治性手术512例,姑息性手术68例,术后化疗519例,以FOLFOX或FCF或XELOX作为一线化疗方案.MC首发癌术后累积生存率明显高于单发结直肠癌（x^2=17.289,P＜0.05）,第二原发癌术后累积生存率与单发结直肠癌比较,差异无统计学意义（x^2=1.731,P＞0.05）.SC累积生存率与单发结直肠癌比较,差异无统计学意义（x^2=0.800,P＞0.05）.结论 MC预后优于单发结直肠癌,而SC预后与单发结直肠癌相当.

英文摘要：

Objective To investigate the clinicopathological features of multiple primary colorectal carcinoma. Methods The clinical data of 30 patients with multiple primary colorectal carcinoma and 580 patients with single colorectal carcinoma who were admitted to the Peking University People＇s Hospital from January 2001 to March 2008 were retrospectively analyzed. There were 16 patients with multiple synchronous carcinoma and 14with multiple metachronous carcinoma. The survival of the patients was analyzed using Kaplan-Meier method and the survival rates were compared using Log-rank test. All data were analyzed using the chi-square test. Results The onset age of multiple metachronous primary carcinoma was younger than that of multiple synchronous carcinoma and single colorectal carcinoma, while the onset age of multiple metachronous secondary carcinoma was close to that of multiple synchronous carcinoma and single colorectal carcinoma. Most of the synchronous carcinoma located at the left colon; while most of the metachronous primary carcinoma located at the rectum and sigmoid colon, and most of the metachronous secondary carcinoma located at the ascending colon. Patients with multiple synchronous carcinoma or multiple metachronous primary carcinoma received radical resection. Of the 14 patients with multiple metachronous carcinoma, 9 received radical resection for secondary focus. Except for three patients with multiple synchronous carcinoma and two patients with multiple metachronous carcinoma, all patients received postoperative chemotherapy with FCF, FOLFOX or XELOX regimen. Of the 580 patients with single colorectal carcinoma, 512 received radical resection, 68 received palliative operation, and 519 received postoperative chemotherapy. The cumulative survival rate of patients with multiple metachronous primary carcinoma was significantly higher than that of single colorectal carcinoma （x2 = 17. 289, P 〈 0. 05）. There was no significant difference in the cumulative survival rate between patients with single co