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[Clinical analysis of 126 patients with primary small cell carcinoma of the esophagus].

OBJECTIVE
To investigate the prognostic factors and the principles of treatment of primary esophageal small cell carcinoma (SCEC) retrospectively.


METHODS
The data of 126 patients with histologically confirmed SCEC treated in our department between May 1985 and June 2005 were retrospectively analyzed. 85 patients were in limited disease stage (LD) and 41 patients as extensive disease stage (ED) according to the Veterans Administration Lung Study Group staging system. Among the 84 patients treated with esophagectomy, 8 cases were in stage I, 16 in stage IIa, 10 in stage IIb, 40 in stage III, 4 in stage IVa and 6 in stage IVb, according to the TNM system (6(th) edition, AJCC). Cox's hazard regression model was used to identify the prognostic factors, and Chi-square test to detect the difference of frequencies among different groups. Kaplan-Meier and log-rank methods were used to estimate and compare the survival rates.


RESULTS
The median follow-up duration of this series was 13 months. One hundred and eight patients died of the disease during the follow-up, 10 were still alive and 8 were lost to follow-up. The 1-, 3-, and 5-year overall survival rates (OS) were 52.2%, 15.9%, and 12.2%, respectively, with a median survival time (MST) of 12.5 months. The 1-, 2-, and 3-year OS were 62.1%, 30.8%, and 22.4% with a MST of 14.0 months for LD, and 29.3%, 13.6% and 2.7% with a MST of 7.0 months for ED, respectively. There was a statistically significant difference in OS between LD and ED (P = 0.0001). The MST of the patients treated with chemotherapy was 14.5 months, significantly longer than the 5.2 months of the patients without (P = 0.0001). Multivariate analysis showed that stage (HR 1.91, 95% CI 1.26 approximately 2.91, P = 0.002), length of the primary lesion (HR 1.75, 95% CI 1.17 approximately 2.63, P = 0.007), and chemotherapy (HR 0.42, 95% CI 0.28 approximately 0.65, P = 0.000) were independent prognostic factors.


CONCLUSION
Esophageal small cell carcinoma is a systemic disease. The tumor stage (LD or ED), length of the primary lesion and chemotherapy are independent prognostic factors. Therefore, a systemic therapy based on chemotherapy should be recommended.