Large cell carcinoma of the lung associated with marked eosinophilia. A case report.

A case of large cell carcinoma of the lung which produced eosinophil colony stimulating factor and eosinophil chemotactic factor was reported. A 52-year-old Japanese man with a tumor in the left upper lobe of the lung underwent left pneumonectomy. Marked eosinophilia persisted especially after recurrence, with a maximum peripheral leukocyte count of 161,000/mm3, of which 78% consisted of eosinophils. The patient died of pulmonary insufficiency 18 months after surgery. At autopsy, metastatic tumor tissues and almost all organs were markedly infiltrated with eosinophils, especially the spleen, and there was marked proliferation of eosinophils in the bone marrow. Eosinophil colony stimulating factor production by the transplanted tumor in a nude mouse was confirmed by use of a human bone marrow culture assay system. Eosinophil chemotactic factor production by metastatic tumor tissue also was proved by a modified micro-filter technique.