No Increased Frequency of Malignant Neoplasms in Polymyalgia Rheumatica and Temporal Arteritis. A Prospective Longitudinal Study of 398 Cases and Matched Population Controls

Objective: To determine the prevalence and incidence of cancer in patients with polymyalgia rheumatica (PMR) and temporal arteritis (TA) compared to matched population controls.

Methods: In a population based study 1987-97, 398 patients were diagnosed with PMR or TA. Each patient was randomly assigned 4 age and sex matched controls from the same county, totaling 1592 controls. All patients and controls were cross-checked with data files at the Cancer Registry of Norway, for cancers registered up to the end of 1998.

Results: Prior to inclusion, cancer was diagnosed in 32 patients with PMR or TA (8.0%) and 153 controls (9.6%) (OR 0.82, 95% CI 0.55-1.22, p = 0.3). After inclusion, malignant neoplasms were discovered in 34 patients with PMR or TA (9.3%) compared to 143 controls (10.8%) (relative risk 0.86, 95% CI 0.59-1.26, p = 0.4). Thus there was no difference between patients with PMR or TA and their controls regarding prevalence or incidence of cancer. The interval between inclusion and the time of diagnosis of malignant neoplasm did not differ between patients and controls. No significant difference in types or localization of malignant neoplasms was found in patients compared to controls.

Conclusion: No differences were found in frequencies or types of malignant neoplasms between patients with PMR or TA and population controls. Neither PMR nor TA as defined by present diagnostic criteria appears associated with cancer.