The rheumatic associations of cancer therapy are highlighted in this review. Interleukin-2, interferon alfa, and Calmette-Guérin bacillus immunotherapies are related to an inflammatory arthritis, and septic arthritis can complicate breast-cancer therapy. In a large retrospective study, an increased incidence of cancer in systemic sclerosis was confirmed, especially lung and breast cancers. Lymphoproliferative associations of Sjögren's syndrome were explored in a study of non-Hodgkin's lymphoma patients in which clinical and histologic criteria were used to diagnose Sjögren's syndrome. B- and T-cell lymphomas continue to be reported with rheumatologic manifestations such as seronegative polyarthritis and sacroiliitis. Malignant angioendotheliomatosis, which mimics central nervous system vasculitis diseases, has been reported. Paraneoplastic associations of lung, ovarian, and renal-cell carcinomas are discussed.