Similar survival rates for rheumatoid and non-rheumatoid cancer patients.

The survival rate for cancer patients with rheumatoid arthritis was compared with that for non-rheumatoid cancer patients. This was accomplished by linking two nationwide Finnish data registers, the Social Insurance Institution's Population Register and the Finnish Cancer Registry. For 2012 of the 2062 rheumatoid patients with cancer diagnosed after the diagnosis of rheumatoid arthritis, the Cancer Registry was successfully searched for a non-rheumatoid of diagnosis of control patient who matched with respect to sex, age, year of diagnosis of cancer and location of the tumour (and also, for leukaemia, with respect to cell type). The 5-year relative survival rate for male rheumatoid patients was 21.2% and, for the control cancer patients, 25.4%. In females, the corresponding rates were 38.2% for the rheumatoid patients and 41.2% for the control patients (p less than 0.05). At some sites, particularly with leukaemia, the rates for the rheumatoid patients were lower than those for the control patients. The difference, however, only reached a 5% significance level for colorectal cancer in males. Rheumatoid arthritis and its treatment do not seem to have any appreciable effect on the survival of cancer patients.