title: Mixed small cell and non-small cell lung cancer.
abstract: Seventeen (10 percent) of 176 patients with small-cell carcinoma of the lung seen at this hospital since 1976 proved to have mixed small-cell and non-small-cell tumors. The presence of a mixed lung cancer was established prior to chemotherapy or irradiation in nine patients. Eight were initially diagnosed as pure small-cell carcinoma but proved to have a mixed tumor at either surgery or autopsy. Of the 17 patients, eight received chemotherapy, and four had a partial response. Six of the 40 autopsies performed on patients with small-cell lung cancer demonstrated intrathoracic tumor which was histologically mixed. Extrathoracic metastases in these patients were heterogeneous and included pure small-cell, pure non-small-cell, and mixed histologic type. We conclude that mixed small-cell and non-small-cell lung cancers are relatively frequent and carry important prognostic and therapeutic implications. Clinical management of patients with small-cell lung cancer should therefore be flexible and tailored to the potential for histologic diversity. Mixed lung cancer in previously untreated patients suggests a common endodermal origin for small-cell and non-small-cell pulmonary tumors.
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D018288:Carcinoma, Small Cell / Q000473:pathology* / Q000628:therapy; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology; D008175:Lung Neoplasms / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009373:Neoplasms, Germ Cell and Embryonal / Q000473:pathology* / Q000628:therapy; D011013:Pneumonectomy