[Small cell bronchial cancer--pathologic anatomy]

Examinations of 635 biopsies and 163 surgical specimens resulted in a morphological description of characteristics of small cell cancer of the lung (cell diameter 9 microns, medial diameter of nuclei 7 microns). Histological diagnosis reflects only a rough phenotypic parameter of this tumor entity. At thorough examination of small cell cancer squamous, adenoid and/or giant cell differentiation can be found within the same tumor tissue in about 20% of specimens. Histological examination of spontaneous and therapeutical induced tumor regression in resected specimens yielded findings such as necrosis, scar development and endangitic blood vessel transformations. Results of electron microscopy, immunohistochemistry and in situ hybridisation also underline a wide range of heterogeneity in the special group of small cell cancer of the lung. The documentation of a broad spectrum of morphological findings in specimens from resected tumors demonstrates that a 2-mm biopsy represents only a rough parameter of a biologically complex tumor.