Arthritis drug may increase chance of cancer

In terms of specific cancers, rheumatoid arthritis patients were more than five times more likely to develop non-Hodgkin's lymphoma and three times as likely to develop melanoma.

There have been previous reports linking the drug to non-Hodgkin's lymphoma, but the melanoma risk is new.

The study looked at 458 patients with rheumatoid arthritis who started Methotrexate therapy at six private practices before June 1986.

The medical records showed that 64 malignancies were diagnosed during a follow-up period which averaged just over nine years and an additional nine cases were diagnosed after the patients were followed up.

Further investigation is needed to determine whether this risk is unique to Australia.