Oat cell carcinoma of the stomach

An autopsy case of oat cell carcinoma arising in the stomach is described. The histology of the tumor was similar to that of ordinary oat cell carcinoma of the lung, and the secretory granules were identified by electron microscopy. Except for the direct invasion of the perigastric region and metastasis of the liver, no tumor was found in the lungs or any other organs. The occurrence of this type of tumor in the stomach as in other extrapulmonary organs provides supplemental evidence for the existence of the carcinoid-oat cell carcinoma group, recently established in the lung.