Patients diagnosed with RA have an increased risk of some cancers. However, limited data are available on the important issue of prognosis of RA patients with cancer.
RA patients were identified from the Swedish Hospital Discharge Register by linkage to the Cancer Registry. Follow-up of patients was started from the date of diagnosis of cancer through year 2006. Hazard ratios (HRs) were calculated in cancer patients with RA compared with subjects without RA.
A total of 1,411,163 cancer patients were identified in the database, of whom 6309 had a previous hospitalization for RA. Compared with all cancer patients without RA, patients with RA had a worse prognosis, with an HR of 1.29 and 1.31 for cause-specific and overall survival, respectively. For specific cancer sites, skin and breast cancers and non-Hodgkin's lymphoma showed worst survival. Age stratification did not change the results.
Cancer patients with a previous hospitalization for RA had a worse prognosis for all and many site-specific cancers compared with patients without RA, independent of age at diagnosis and tumour staging. Improvement of survival for cancer patients with RA may require a multidisciplinary approach to accommodate the comorbidity.