Coexistence of Kaposi's sarcoma and rheumatoid arthritis

Kaposi's sarcoma (KS) which is a neoplastic disease has many different clinical forms with the same histopathological features. KS may associate with many rheumatic diseases due to intensive immunosuppressive therapy used in the treatment. In this study, we present two patients with KS who also had rheumatoid arthritis (RA) to highlight the coexistence of both diseases. KS developed before the immunosuppressive treatment in one of the cases and during immunosuppressive treatment in the other. Unlike in previously reported studies, in our case, KS occurred before the immunosuppressive treatment was started. Therefore, the immunosuppressive treatment cannot be responsible for the coexistence of KS and RA in our first case.