Cancer in biopsy-proven giant cell arteritis. A population-based study.

Objective: To investigate the potential association between giant cell arteritis (GCA) and cancer in a series of consecutive patients diagnosed with biopsy-proven GCA over a 25-year period at the single reference hospital for a well-defined population.

Methods: The case records of all patients diagnosed with biopsy-proven GCA at the Department of Medicine of the Hospital Xeral-Calde (Lugo, Northwest Spain) between January 1, 1981 and December 31, 2005 were reviewed. Information on cancer and cause of death over the extended follow-up was assessed. In all cases the presence of cancer was histologically confirmed.

Results: Cancer was found in 39 (15.3%) of the 255 GCA patients. Although 7 (18%) of the 39 patients had cancer either at the time or within the first 12 months after GCA diagnosis, the standardized mortality ratio (SMR) due to cancer in patients with biopsy-proven GCA showed no increase (overall SMR 1.06 [0.65-1.60]; men, 0.81; women, 1.50). The time interval between GCA diagnosis and cancer diagnosis was 5.2+/-3.8 years (median 4.2 years; interquartile range: 3-7 years). When multivariate analysis adjusted by age and sex was performed, only the presence of dysphagia (adjusted hazards ratio (HR)=3.90; P=0.04), abnormal temporal artery on physical examination (adjusted HR=4.61; P=0.04), and anemia at the time of GCA diagnosis (adjusted HR=3.39; P=0.01) were associated with an increased risk of cancer over the extended follow-up.

Conclusions: The results from this series do not support an overall increase of mortality due to cancer in GCA.