Kaposi's sarcoma, or idiopathic multiple hemorrhagic of Kaposi's sarcoma are rarely diagnosed prior to death. earcoma, is a multifocal neoplasm with a possible viral Two patients with unusual pulmonary and cardiac etiology which predominaatlv affects the skin. Internal manifestations of Kaposi's sarcoma are presented and lesions occur in 10-20 percent of patients and are im- the thoracic complications of Kaposi's sarcoma are portant due to their hemorrhagic tendencies. However, discussed. dne to their lack of specific symptoms, internal tumors hysicians are often confronted with the challenge Pof diagnosing a suspected internal malignancy and finding the primary site of involvement. The patient may present with weight loss, gastrointestinal bleeding, hematuria, enlarged liver or spleen, cough, dyspnea, hemoptysis, pulmonary infiltration on chest x-ray film, signs of congestive heart failure or pericarditis, lymphadenopathy and abdominal, chest or bone pain. The most frequently diagnosed malignancies include carcinoma of the lung, breast, prostate, stomach, colon, kidney, uterus, cervix and ovary and lymphomas and leukemias. A rare cause of internal neoplasia is Kaposi's sarcoma or multiple idiopathic hemorrhagic sarcoma. The diagnosis of visceral Kaposi's sarcoma is important due to the hemorrhagic tendencies of the tumors and their potential treatment with surgery or chemotherapy, but is difEcult due to their rarity and lack of symptoms. Their diagnosis is often made at autopsy. We have recently observed two patients with Kaposi's sarcoma with unusual internal lesions and their cases are presented to alert physicians to include Kaposi's sarcoma in the differential diagnosis of suspected internal malignancy. A 80-year-old Negro man was admitted to the Veterans Administration Hospital in Albany, NY, with a two-year history of proximal muscle weakness and skin lesions. When the present illness began, he was evaluated at another hospital where workup disclosed elevated creatinine phosphokinase CPK and serum glutamic oxaloacetic transaminase. A skin biopsy was performed which showed vascular proliferation with hemosiderin deposition in the dermis and was interpreted as Kaposi's sarcoma. Gastrocnemius muscle biopsy disclosed fiber necrosis and regeneration, myophagocytosis, and chronic interstitial infiltrate which was consistent with polymyositis. The patient was placed on prednisone, 80 mg daily, with