Risk of cancer in patients with biopsy-proven giant cell arteritis.

OBJECTIVE Results of previous studies investigating the association between GCA and malignancy are conflicting. We performed a study of the risk of cancer in patients with biopsy-proven GCA. METHODS Patients with biopsy-proven GCA were identified from pathology reports of temporal artery biopsies from the major pathology laboratories in South Australia (SA). All subjects with biopsy-proven GCA were linked to the SA Cancer Registry to identify cases of cancer until 31 December 2006. Standardized incidence ratios (SIRs) for cancer were determined using the age- and gender-specific rates for SA. RESULTS There were 226 cases of biopsy-proven GCA (163 females and 63 males). Thirty-one cases were diagnosed with cancer, following the diagnosis of biopsy-proven GCA. There was no increased risk of cancer among those with biopsy-proven GCA, following the diagnosis of GCA compared with the general population (SIR 1.2; 95% CI 0.8, 1.6). CONCLUSION This cohort study did not demonstrate any increased risk for malignancy in subjects with biopsy-proven GCA.