[Incidence of cancer among Japanese patients with rheumatoid arthritis].

Most follow-up studies of patients with rheumatoid arthritis demonstrate no increase in the incidence of cancer apart from approximate doubling of the incidence of lymphoproliferative malignancies. A consecutive series of 1832 Japanese patients with rheumatoid arthritis seen at the center was studied to determine their cancer morbidity. Overall, 35 cancers were diagnosed in the series from 1982 through 1995 and were not significantly in excess of the expected number. No association was found between rheumatoid arthritis and subsequent development of cancer at any site, either.