Is cancer associated with polymyalgia rheumatica? A cohort study in the General Practice Research Database

Abstract

ObjectiveTo investigate the incidence of new cancer diagnoses in a community sample of patients with polymyalgia rheumatica (PMR).MethodsAll incident cases of PMR in the UK General Practice Research Database (GPRD) (1987–99), without pre-existing cancer or vascular disease and treated with corticosteroids (n=2877) were matched with up to five age, sex and GP practice patients without PMR (n=9942). Participants were followed up until first cancer diagnosis, death, transfer out of the database or end of available records.ResultsThe mean age of the sample was 71.6 years (SD 9.0), 73% were female. Median follow-up time was 7.8 years (IQR 3.4, 12.3). 667 (23.2%) people with a PMR diagnosis developed cancer compared with 1938 (19.5%) of those without PMR. There was an interaction between PMR status and time. In the first 6 months after diagnosis, those with a PMR diagnosis were significantly more likely to receive a cancer diagnosis (adjusted HR (95% CI): 1.69 (1.18 to 2.42)). The number of events was small, but occurrences of prostate, blood, lymph nodes, female reproductive and nervous system cancers may be more common in those with PMR in the first 6 months after PMR diagnosis.ConclusionsAn increase in the rate of cancer diagnoses was noted in the first 6 months of observation, but we were unable to determine whether the cancer incidence in PMR was different from controls, beyond this time point. Clinicians should ensure they fully exclude cancer as a cause of PMR-like symptoms and monitor patients for possible malignancies.

The real evidence for polymyalgia rheumatica as a paraneoplastic syndrome

“…Eight of the nine articles identified through the systematic search described cohort stud- (Table I) (15)(16)(17)(18)(19)(20)(21)(22). Two articles utilised the same dataset, but with one considering the outcomes of cancer diagnosis and the other causes of death including cancer (19,20).…”

Advances and challenges in the diagnosis and treatment of polymyalgia rheumatica

“…Over a median follow up of 7.8 years, 23.2% of patients with PMR developed cancer compared with 19.5% of controls [Muller et al 2013]. The risk of malignancy was increased in patients with PMR during the first 6 months after diagnosis (hazard ratio 1.69; 95% confidence interval 1.18-2.42) [Muller et al 2013]. Misdiagnosis may account for these findings and this highlights the importance of careful evaluation of patients presenting with polymyalgic symptoms to exclude other conditions.…”

The real evidence for polymyalgia rheumatic as a paraneoplastic syndrome

“…However, this may also mean that any short-term association with cancer is diluted by a lower risk of malignancy in the longer term. Indeed, the two studies in our review that specifically looked at intervals of time from PMR diagnosis showed an initial increase in the risk of malignancy, followed by a return to normal risk (5,6). Finally, we agree that a specific cohort study may well be the only way to definitively answer the question as to whether PMR is a truly paraneoplastic condition.…”

“…tertiary care (4), primary care (5)]. Furthermore, Bellan and colleagues (2) highlight the related point of our exclusion of existing cancer in our previous study (5). Whilst we may accept that if PMR were a paraneoplastic syndrome, it does not need to occur before the malignancy is diagnosed, British guidelines for the diagnosis of PMR state that malignancy is an important differential diagnosis of polymyalgia symptoms and hence should be excluded as the cause of symptoms before a diagnosis of PMR is made.…”