[Peripheral small cell carcinoma, atypical and typical lung carcinoids (morphologic features, cell oncogene expression, DNA histospectrophotometry)].

Morphogenetic and molecular-biological features of the lung peripheral tumours (small-cell carcinoma, atypical and typical carcinoid) were studied on the surgical material from 68 patients. Spectrum of histologic, histochemical, immunohistochemical (immunohistochemistry of oncoproteins c-fos, c-myc, c-ras, c-sis and c-src) methods, DNA histospectrophotometry by plug-method, electron microscopy, semithin section morphometry, statistical and correlation analysis were used. Small-cell carcinoma is shown to be a heterogeneous group of tumours that includes tumours with endocrine cell differentiation, endocrine and epidermoid and/or glandular, undifferentiated cell carcinoma. Lymphocyte-like carcinoma and intermediate cell carcinoma with endocrine cell differentiation are distinguished from other types of lung carcinoma by their low, sometimes diploid DNA content that does not correlate with its malignancy as well as by a low level of expression of cell oncogenes c-fos, c-ras, c-sis. Small-cell carcinoma with endocrine cell differentiation, atypical and typical lung carcinoids represent a unique histogenetic group of endocrine lung tumours that differ from each other by the degree of anaplasia.