[Treatment and prognosis of extrapulmonary small cell carcinoma of 243 cases]

Abstract

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 multimodal 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.