中文摘要：

目的 探讨多重癌（MPC）的临床特点及影响其预后的因素.方法 回顾性分析290例MPC患者的临床资料,分析MPC患者首发癌和次发癌受累器官分布,探讨影响患者预后的因素.结果 290例MPC患者共580个恶性病灶,以二重癌为主;男性发病年龄大于女性,男女发病比例为0.986：1;肿瘤发生部位以消化系统最多;首发癌好发于结直肠（13.1％）、乳腺（12.4％）和鼻咽部（11.7％）;次发癌好发于肺（18.6％）、结直肠（12.8％）和肝（9.3％）.197例异时性MPC患者的中位肿瘤诊断间隔时间为54个月.多因素分析结果显示,次发癌系统类型、合并高血压、糖尿病、甲亢为影响MPC患者预后的独立危险因素（均P〈0.05）.结论 MPC患者肿瘤好发于消化系统;次发癌系统类型及合并高血压、糖尿病、甲亢是影响MPC预后的危险因素.

英文摘要：

Objective To explore the clinical features and factors affecting the prognosis of multiple primary cancer （ MPC ） . Method s Clinical data of 290 patients with MPC were retrospectively analyzed .The distribution of first primary cancer and second primary cancer organs involved was analyzed ,and the factors affecting the prognostic of these patients were explored .Results A total of 290 patients （580 malignant foci ） with MPC were dominated by double primary cancer .The onset age in males was greater than that in females ,and the proportion of male onset to female onset was 0.986 ：1.The malignancies most commonly occurred in digestive system .The first primary cancer mainly occurred in colon and rectum （13.1%）,breast（12.4%）,and nasopharynx （11.7%）.The second primary cancer mainly occurred in lung（18.6%）,colon and rectum（12.8%）,and liver（9.3%）.The median interval of tumor diagnosis was 54months among 197 patients with metachronous MPC .The results of multivariate analysis showed that the category of secondary cancer system ,complication with hypertension,diabetes or hyperthyroidism were the independent risk factors influencing the prognosis of MPC patients （all P〈0.05）. C onclusion The malignancies most commonly occur in digestive system in MPC patients .The category of second primary cancer system , complication with hypertension ,diabetes or hyperthyroidism are the risk factors influencing the prognosis of MPC patients .