Diffuse pulmonary tumor microemboli from prostatic carcinoma with an associated fibrous histiocytic sarcoma.

Diffuse tumor microemboli to the lungs from prostatic carcinoma are extremely rare, with only six reported cases in the literature published in English. Here a seventh case is reported. The patient resembled the previously reported cases in the following ways: (1) There were minimal chest x-ray findings; (2) there was no other evidence of significant parenchymal or lymphangitic tumor involvement; and (3) pulmonary hypertension developed, but without signs of cor pulmonale. The case was even more unusual because of the presence of an apparent second neoplasm, ie, a malignant fibrous histiocytic sarcoma primary in the chest wall. There were wide-spread "collisional metastases" (metastases from each malignancy at the same site).