Kaposi's sarcoma associated with lung cancer and immunosuppression.

We report a 65-year-old Japanese woman with Kaposi's sarcoma (KS). The eruption first occurred on the legs while she was admitted for treatment of poorly differentiated lung cancer. Approximately eight months after the evolution, cutaneous tumors rapidly spread to the forearms, trunk, and pharynx. At that time, the patient had received systemic corticosteroid (10-40 mg/day of prednisolone) for about three months to reduce pulmonary inflammation. The laboratory data showed anemia, lymphopenia, hypogammaglobulinemia, and a decreased T cell count, although the serological test for HIV infection was negative. The patient was treated with radiation (X-ray for KS of pharynx and electron beam for KS of lower legs) and local intralesional injection of vinblastine. Although both therapies were very effective and well tolerated, she died of bacterial pneumonia and sepsis. Autopsy revealed KS tumors, unknown before death, in both lungs, the esophagus, and the stomach. The left lung cancer had disseminated and metastasized to the right lung, pleura, mediastinum, and abdominal cavity. It is suspected that chronic respiratory distress and systemic use of corticosteroids might have induced the rapid extension of KS.