Polygenic risk scores allow risk stratification for keratinocyte cancer in organ transplant recipients

Organ-transplant recipients have an elevated risk of keratinocyte cancers: basal cell carcinoma (BCC) and squamous cell carcinoma. We assessed whether polygenic risk scores (PRSs) generated in nontransplantees from the UK Biobank and 23andMe (13,981 squamous cell carcinoma, 33,736 BCC, and >560,000 controls) can predict keratinocyte cancer risk in an independent organ-transplant recipient cohort. After adjusting for traditional risk factors, compared with the bottom 20%, organ-transplant recipients in the top 20% PRS had an increased risk of BCC (OR = 3.25, 95% confidence interval = 1.44–7.31, P = 4.4 × 10-3) and squamous cell carcinoma (OR = 2.11, 95% confidence interval = 0.98–4.53, P = 0.055). For BCC, the top 20% PRS individuals had an absolute risk of 23%, whereas the risk in the bottom 20% was similar to that in the general nontransplantee population. Adding PRS to a model containing traditional skin cancer risk factors yielded a 3% increase in the area under the curve for receiver operating characteristic curve for BCC (0.73 vs. 0.70); adding the PRS did not significantly increase the area under the curve for receiver operating characteristic curve for squamous cell carcinoma. Organ-transplant recipients in the highest genetic risk quintile could benefit from more intense keratinocyte cancer screening and preventive strategies compared with their counterparts. The BCC PRS improves prediction over and above the traditional skin cancer risk factors by 3%.