title: Risk of malignancy in patients with giant cell arteritis and polymyalgia rheumatica: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To investigate the association between giant cell arteritis (GCA)/polymyalgia rheumatica (PMR) and malignancy risk.
  
  
  METHODS
  We conducted a systematic review and meta-analysis of cohort studies that reported relative risk, hazard ratio, or standardized incidence ratio (SIRs) with 95% confidence comparing malignancy risk in patients with GCA/PMR versus non-GCA/PMR participants. Pooled risk ratios and 95% confidence intervals were calculated using a random-effect, generic inverse variance method.
  
  
  RESULTS
  A total of six studies were identified and included in our data analysis. The pooled risk ratio of malignancy in patients with GCA/PMR was 1.14 (95% CI: 1.05-1.22). The risk was higher in the first 6-12 months after diagnosis with the pooled risk ratio of 2.16 (95% CI: 1.85-2.53). However, when we performed a sensitivity analysis that excluded one study with a potential selection bias, the pooled risk ratio decreased and did not achieve statistical significance.
  
  
  CONCLUSIONS
  Our study demonstrated a low but statistically significant increased malignancy risk among patients with GCA/PMR. However, when we excluded one study with potential selection bias, the new pooled risk ratio did not achieve statistical significance.
authors: Department of Internal Medicine, Bassett Medical Center and Columbia University College of Physicians and Surgeons, Cooperstown, NY; Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Electronic address: P.Ungprasert@gmail.com.
authors: Patompong
authors: P
authors: Ungprasert
authors: Department of Preventive and Social Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors: Anawin
authors: A
authors: Sanguankeo
authors: Department of Preventive and Social Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors: Sikarin
authors: S
authors: Upala
authors: Department of Internal Medicine, Bassett Medical Center and Columbia University College of Physicians and Surgeons, Cooperstown, NY.
authors: Eric L
authors: EL
authors: Knight
mesh_terms: D013700:Giant Cell Arteritis / Q000150:complications*; D006801:Humans; D015994:Incidence; D009369:Neoplasms / Q000453:epidemiology*; D011111:Polymyalgia Rheumatica / Q000150:complications*; D012307:Risk Factors
keywords: Epidemiology; Giant cell arteritis; Malignancy; Meta-analysis; Polymyalgia rheumatica