Sebaceous Carcinoma Incidence and Survival Among Solid Organ Transplant Recipients in the United States, 1987-2017.

Importance Risk of sebaceous carcinoma (SC), a rare skin cancer associated with Muir-Torre syndrome, is elevated among solid organ transplant recipients (SOTRs). However, population studies evaluating this association and assessing survival for posttransplant cases are lacking, and further understanding of SC epidemiology in this immunosuppressed population could provide etiologic and clinical insights. Objective To assess SC incidence and patient survival after solid organ transplantation. Design, Setting, and Participants This cohort study, conducted from January 1, 1987, to December 31, 2017, used data from the Transplant Cancer Match Study, which links transplant and cancer registry data for 17 states and 1 metropolitan area in the United States. Altogether, these registries account for approximately 46% of all US transplants. Data on demographic and transplant characteristics as well as induction and initial maintenance immunosuppressive therapies were obtained from the transplant registry. Standardized incidence ratios (SIRs) comparing SC incidence among SOTRs to the general population were calculated. Incidence rate ratios (IRRs) comparing SC risk between SOTR subgroups were calculated using multivariate Poisson regression. Cox regression was used to compare overall survival between SC cases in SOTRs and other individuals. Main Outcomes and Measures Sebaceous carcinoma incidence and overall patient survival after transplantation compared with the general population. Results A total of 326 282 transplant procedures were performed for 301 075 patients (No. [%] age at transplant, 126 550 [38.8%] aged 0-44 years; 82 394 [25.3%] aged 45-54 years; 82 082 [25.5%] aged 55-64 years; 35 256 [10.8%] aged ≥65 years; 201 354 male patients [61.7%]; 202 557 White patients [62.1%]). A total of 102 SCs were diagnosed in 301 075 SOTRs, corresponding to a 25-fold increased incidence (SIR, 24.8; 95% CI, 20.2-30.1). Incidence was especially elevated among lung recipients (SIR, 47.7; 95% CI, 20.6-94.0) and after a posttransplant diagnosis of cutaneous squamous cell carcinoma (SIR, 104.0; 95% CI, 62.8-163.0). Among SOTRs, factors independently associated with SC risk included male sex (IRR, 2.46; 95% CI, 1.48-4.07; P < .001), race/ethnicity (non-Hispanic Black vs non-Hispanic White, IRR, 0.28; 95% CI, 0.10-0.77; P = .01), older age (IRR, 7.85; 95% CI, 3.85-16.0; ≥65 vs 0-44 years; P < .001 for trend), use of thymoglobulin induction (IRR, 1.82; 95% CI, 1.16-2.86; P = .009), posttransplant cutaneous squamous cell carcinoma (IRR, 4.60; 95% CI, 2.67-7.94; P < .001), and longer time since transplant (IRR, 8.40; 95% CI, 3.94-17.90; ≥10 vs 0-1.9 years; P < .001 for trend). Muir-Torre syndrome-associated cancers were rare among both SOTRs and others with SC (3.3%-4.1%). Among patients with SC, prior transplantation was associated with increased overall mortality (adjusted hazard ratio, 2.09; 95% CI, 1.45-3.01), although few deaths were attributed to SC (4 of 92 SOTRs [4.3%]; 235 of 3585 non-SOTRs [6.6%]). Conclusions and Relevance Among SOTRs, results of this large cohort study suggest that SC was associated with measures of immunosuppression, and overall survival was worse than for other patients with SC. Findings also suggest a possible role for UV radiation in carcinogenesis.