243例肺外小细胞癌患者的治疗及预后分析

Treatment and prognosis of extrapulmonary small cell carcinoma of 243 cases

目的探讨肺外小细胞癌（EPSCC）的临床特点、治疗方法和预后。方法回顾性分析1977年至2007年中国医学科学院肿瘤医院收治的243例EPSCC患者的临床资料。243例EPSCC患者中，局限期209例，广泛期34例；采用以化疗为基础的综合治疗者170例，局部治疗[手术和（或）放疗]者73例。结果EPSCC的原发部位以消化道多见，占67．9％。全组243例患者的半年、1年、2年、3年和5年总生存率分别为88．9％、67．2％、36．8％、27．3％和18．3％。局限期患者的中位生存时间（18．6个月）明显长于广泛期患者（14．0个月，P=0．030）。无脉管瘤栓者的中位生存时间（19．2个月）明显长于有脉管瘤栓者（14．4个月，P=0．026）。无区域淋巴结转移者的中位生存时间（39．5个月）明显长于有区域淋巴结转移者（13．9个月，P=0．000）。多因素分析显示，肿瘤的美国退伍军人肺癌协会（VALSG）分期、有无脉管瘤栓和根治术后区域淋巴结转移情况是影响EPSCC患者预后的独立因素。不同原发部位EPSCC患者的中位生存时间差异无统计学意义（P=0．075），其中妇科肿瘤、头颈部肿瘤和消化道肿瘤患者的中位生存时间分别为28．0、20．1和14．3个月。采用以化疗为基础的综合治疗者的中位生存时间为20．2个月，明显长于局部治疗的患者（12．2个月，P=0．000）。80．4％的局限期患者在治疗过程中出现远处转移。结论EPSCC是一种少见的恶性肿瘤，易发生早期转移，预后不佳。EPSCC的部分临床特点与小细胞肺癌有相似之处，但是在病因学、临床转归、预后和脑转移率等方面又有不同。手术切除后联合化疗和放疗的综合治疗有可能会改善EPSCC的治疗效果。

Objective The extrapulmonary small cell carcinoma （EPSCC）, a uncommon malignant tumor, has seldom been reported. The aim of this study was to analyze the clinical characteristics, treatment and prognosis of EPSCC. Methods The clinical data of 243 patients admitted in our hospital from 1977 to 2007 were reviewed. The survival rate was calculated by the Kaplan-Meier method and log-rank test. Results The median age of the patients was 58 years and the male-to-female ratio was 2.47： 1. According to VALSG criteria, 209 patients had limited disease （LD） and 34 had extensive disease （ED）. 170 patients received chemotherapy-based muhimodal therapy, 73 received surgery, and/or radiotherapy. The 6, 12, 24, 36 and 60-month survival rates of these patients were 88.9%, 67.2% , 36.8% ,27.3% and 18.3% , respectively. The clinical stage, vessel involvement and regional lymph node metastases were independent prognostic factors of EPSCC. Patients with LD had a median overall survival of 18.6 months compared with 14.0 months in patients with ED （ P = 0. 030 ）. The median survival was 19.2 months for the patients without vessel involvement and 14.4 months with vessel involvement （P = 0. 026 ）. The median survival of the patients with regional lymph node metastases was 13.9 months, while 39.5 months without regional lymph node metastases （ P = 0. 000）. Among different primary sites, patients with gynecologic small cell cancer had a median survival of 28.0 months, head and neck 20.1 months and gastrointestinal tract 14.3 months. Brain metastasis was observed in a lower number of patients with EPSCC compared with that in patients with SCLC. There were no statistically significant differences in overall survival between patients with pure and mixed EPSCC （ P = 0. 396）. Conclusion EPSCC is an uncommon malignant tumor with early metastasis and poor prognosis. The clinical characteristics of EPSCC and SCLC were similar in some aspects, however, there are some differences in etiology, clinic course, survival and frequency of brain metastases. These differences may influence the choice of therapeutic strategy. Multimodal therapy,combination of chemo- and radio-therapy after surgical resection may improve the outcome of EPSCC.