Risk of Cancer Among Sarcoidosis Patients With Biopsy-verified Nonnecrotizing Granulomatous Inflammation: Population-based Cohort Study

Objective: To assess the long-term risk of hematologic cancers, invasive solid tumors, and nonmelanoma skin cancer (NMSC) among sarcoidosis patients with biopsy-verified nonnecrotizing granulomatous inflammation.

Methods: We used Danish administrative registers with nationwide coverage to construct a cohort of 3892 patients with sarcoidosis and an age- and sex-matched comparison cohort of 38,920 population controls. For all patients, a biopsy demonstrating nonnecrotizing granulomatous inflammation had been obtained from the lower respiratory tract at the time of diagnosis. Study outcome was time to diagnosis of cancer. Follow-up began at time of sarcoidosis diagnosis and continued for up to 10 years. We calculated hazard ratios (HRs) as estimates of the cancer risk among the patients with sarcoidosis relative to that among the population controls and used cumulative incidence functions to calculate absolute 10-year risk estimates.

Results: We observed an increased long-term risk of hematologic cancers (HR during the first 2 years of follow-up: 2.71 [95% CI 1.18-6.25]; HR after > 2 years of follow-up: 2.12 [95% CI 1.29-3.47]) and NMSC (HR after > 2 years of follow-up: 1.82 [95% CI 1.43-2.32]) among the patients with sarcoidosis. An increased risk of invasive solid tumors was only observed during the first 2 years (HR 1.55, 95% CI 1.18-2.04). Compared with the population controls, the patients with sarcoidosis had an increased absolute 10-year risk of hematologic cancers (risk difference 0.56%, 95% CI 0.11-1.01%) and NMSC (risk difference 1.58%, 95% CI 0.70-2.47%).

Conclusion: Sarcoidosis patients with biopsy-verified nonnecrotizing granulomatous inflammation have an increased long-term risk of hematologic cancers and NMSC compared with the general population.