Age at organ transplant vs. organ type received greater predictor of recurring skin cancer

Although recipients of all organ types develop additional skin cancer, age at transplant was a greater predictor than organ type for recurring cases, according to a cohort study.

“Skin cancers, particularly cutaneous squamous cell carcinomas, are an important cause of morbidity and mortality among organ transplant recipients,” Lee Wheless, MD, PhD, assistant professor of dermatology at Vanderbilt University School of Medicine, and colleagues wrote. “The aim of this study was to characterize further those [organ transplant recipients (OTRs)] who develop multiple skin cancers and to assess for patterns of development of additional skin cancers after the first skin cancer by patient age and transplanted organ type.”

To identify 5,129 solid organ transplant recipients that underwent transplant surgery, the cohort used validated electronic health record-based data from a single tertiary care academic medical center. All patients were aged older than 18 years and had surgery between 1992 and 2017. The study was limited to white patients due to their higher skin cancer risk.

The cohort found that patients with skin cancer tended to be older (64.8 vs. 57.2 years), received a transplant at an older age (53.7 vs. 50.9 years) and had a longer follow-up after transplant (11 vs. 5.9 years). The greatest proportion of skin cancers at 17.7% were in lung transplant recipients. This was followed by kidney transplant recipients at 16.5% and heart transplant recipients at 16.1%. Liver transplant recipients had the lowest proportion of skin cancers at 6.8%.

Additionally, recipients of kidney transplants and heart transplants had a higher mean number of skin cancers per patient (11.9 and 9.9, respectively), whereas recipients of liver transplants and lung transplants maintained lower averages (5.2 and 4.9, respectively). However, when analyzing subsequent skin cancer cases, the researchers found that there was no significant difference in risk between organ types when considering previous skin cancer as baseline.

After transplant, there was a steady increase in the risk of first skin cancer risk among all age groups with the risk of skin cancer increasing monotonically with age at transplant for first (P < .001), second (P < .001) and third (P < .02) skin cancers (P < .001).

“In this single-institution cohort study, we observed in more than 5,000 solid OTRs that age at transplant was a greater predictor of skin cancer risk than organ type,” Wheless and colleagues wrote. “Future studies are needed to better characterize those patients who will develop numerous skin cancers or identify those who will remain free from skin cancer.”