[Morphologic and molecular-genetic characterization of lung cancer developing in people who have worked at nuclear facilities and who have lived in Russian territories polluted after the accident at the Chernobyl power plant].

Clinicomorphological analysis of 15 lung carcinomas of patients who had been exposed for a long time to the radiation after the Chernobyl accident was performed. The material consisted of 10 surgical and 5 autopsy cases and was studied at the light, electron microscopic and immunohistochemical level. There were 6 peripheral, 8 central carcinomas and one massive tumor. Fibrous areas with many dust particles were found in peripheral carcinomas. In central tumors chronic obstructive bronchitis with epithelial dysplasia and metaplasia was observed. Carcinoma was represented by various histologic types: small cell (4 cases), combined small cell with squamous differentiation (5 cases), adenocarcinoma (5 cases), adenosquamous type (1 case). Peculiar calcium deposits in both stroma and parenchyma were found in tumors with glandular differentiation. Morphogenesis of calcium microdeposits may be connected with dust radioactive particles elimination. Central carcinoma had, in the majority of cases, a neuroendocrine differentiation and can be related to some types of small cell carcinoma. Peripheral cancer was mostly of a glandular differentiation and was, as a rule, carcinoma in the scar. Lung carcinomas studied had peculiar molecular-genetic features: lack or low bcl-2 expression, low Ki-67 expression and a high degree of c-myc expression. Tumors were characterized by a low apoptosis index independently of a histologic type. Apoptosis was not complete: lack of apoptotic bodies phagocytosis this resulting in postapoptotic detritus formation.