RESUMEN
We report a 58-year-old male with localized pleural adenocarcinoma, the origin of which was not identified. The disk-shaped pleural tumor was 8 x 6 x 2 cm in size and involved the left upper chest wall including the ribs. A fine needle biopsy showed adenocarcinoma, but whole body survey revealed no neoplasm other than the chest wall tumor. The left chest wall resection was followed by the left pleuropneumonectomy, because a few disseminations were identified in the visceral pleura. Pathological examinations showed no primary tumor in the lung. Immunohistochemical examinations suggested that micro-adenocarcinoma originating the subpleural lung invaded chest wall. It may be possibly a subtype of pseudomesotheliomatous adenocarcinoma. The patient has no recurrent tumor 1 year after the operation.