Clinicopathological Study of 41 Resected Small Cell Lung Carcinomas

Using histopathological method, we analyzed the relationships among the subtypes, localization of the tumors, chemotherapeutic effects, and prognosis of the diseases in 41 small cell lung carcinoma patients surgically resected in our department and Nishi-Niigata Hp.Keratin,epithelial membrane antigen（EMA）and carcinoembryonic antigen（CEA）were used as markers of epithelial cells, gastrin releasing peptide（GRP）, chromogranin A（chr. A）, neuronspecific enolase（NSE）and Leu 7 were used as markers of neuroendocrine cells, and c-myc, p53 were used. Patients were classified into 3 subtypes：1)oat cell carcinoma（OAT）, 2)intermediate cell type（INT）, and 3)small cell carcinoma with large cell component（SC/LC）according to the Radice's criteria. Immunohistological positive rate are as follows. Keratin 60%, EMA 84%, CEA 74%, GRP 62%, chr. A 47%, NSE 97%, Leu 7 62%, p53 32%, c-myc 49%. There were no differences in parcentages of positive staining among the subtypes and the localization of the tumors. The cases of positive staining for GRP and the cases of negative staining for kertin were reactive for chemotherapy. The mean 5-year survival was greater in patients with nagative staining for chr. A than in patients with positive staining for chr. A. chr. A might be a prognostic factor for SCLC