Synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma.

Synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma is rare. Cases from the archives of 2 large referral centers were reviewed to identify cases of synchronously occurring pulmonary carcinoma and pleural diffuse malignant mesothelioma. Three cases of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma were identified from more than 16,000 pleuropulmonary cases and were reviewed for demographic, clinical, radiographic, histologic, and immunohistochemical findings. The patients were men who were 63, 67, and 77 years old. Two had positive smoking histories; the smoking history of the other patient is unknown. One patient had a positive history of asbestos exposure; one patient had no history of asbestos exposure; and one patient's history of asbestos exposure is unknown. The patients underwent surgery for treatment of adenocarcinoma that was diagnosed preoperatively. Two of the adenocarcinomas were of a predominantly bronchioloalveolar pattern. No diffuse malignant mesothelioma was identified preoperatively. Diffuse malignant mesothelioma was suspected on the basis of pleural involvement by tumor with histology differing from that of the adenocarcinoma. Tumor immunostaining supported the diagnoses. The average survival after diagnosis was 6 weeks or less. In summary, the paucity of cases at 2 large referral centers and the paucity of cases reported in the English language literature highlights the rarity of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma. These synchronous neoplasms occur in patients who have risk factors for both neoplasms independently. Length of survival following diagnosis is bleak.