Histologically intact human adenocarcinoma of the lung maintained in nude mice by serial subcutaneous transplantations (4 generations) was harvested and transplanted to the parietal pleura of 11 other nude mice via a novel thoracotomy procedure. Local and regional tumor growth of transplanted tumors occurred in all cases within 31 days, resulting in weight loss, decreased physical activity and death. This rapid-growth "patient-like" model of direct transplantation of a human neoplasm to the parietal pleura may facilitate basic research of pleural malignancies, and stimulate studies of pleural tumor response to cytotoxic treatment, biologic modifiers, and other modalities of treatment. and other modalities of treatment.