폐외소세포암의 임상적 고찰

Abstract

Background : Small cell carcinoma(SCC) was first described in the lung and represents 20-25% of all bronchogenic carcinoma. On the other hand, extrapulmonary small cell carcinoma(EPSCC) is a relatively rare disease, encompassing 2.5-4% of all SCC. This study aimed to review the clinical features, therapy and natural course of patients with EPSCC in single-institution series. Methods : We retrospectively reviewed the medical records of patients with SCC between December 2002 and August 2005. Study eligibility required that patients had pathologically proven SCC in sites other than lung and normal radiological findings of the chest and normal sputum cytology or negative bronchoscopic findings. Result : Eight patients with EPSCC were identified and primary sites were various: Esophagus 4 cases(50%), kidney 1 case, thymus 1 case, stomach 1 case, unknown primary supraclavicular lymph node 1 case. The 4 patients were classified as limited disease(LD) and 2 patients were as extended disease(ED) at initial staging work-up. But 2 patients were undetermined. The 3 patients with LD EPSCC were treated with operation and adjuvant chemotherapy or chemotherapy and radiotherapy and one received only supportive care. They showed a favorable clinical course, with a median time to failure of 15 months and a median overall survival of 23 months. ED EPSCC and undetermined group received only supportive care. They had aggressive clinical course, with a median overall survival of 3 months. Conclusions : EPSCC was identified in various sites, with the most common primary site being the esophagus. It was predominantly occurred in old patients and male and associated smoking likely small cell lung cancer. EPSCC is a relatively rare disease that mimics small cell lung carcinoma in its response to treatment and survival pattents, it would appear advisable to follow similar treatment guidelines. LD EPSCC patients received treatment(chemotherapy, operation, radiation therapy) and a significant survival benefit was noted, but the responses recurred within short terms. EPSCC is usually a fatal disease, meidan overall survival 18 months.