Incidence of Posttransplant Skin Cancer High in Organ Transplant Recipients

Occurrence of posttransplant skin cancer, including squamous cell carcinoma, melanoma, and Merkel cell carcinoma, was common among a group of organ transplant recipients, according to the results of a multicenter study published in JAMA Dermatology. The study showed that risk for posttransplant skin cancer was increased with age ≥ 50 years, white race, male sex, and thoracic organ transplantation.

“The high incidence of posttransplant skin cancer highlights the need for tumor surveillance after organ transplantation, especially in patients with high-risk features,” wrote researcher Giorgia L. Garrett, MD, of the University of California, San Francisco Medical Center, and colleagues. “These data can be used to inform risk stratification and screening guidelines for skin cancer in organ transplant recipients.”

Although it is known that skin cancer commonly occurs after organ transplantation, no prior study estimated the posttransplant population–based incidence in the United States. This study evaluated the incidence and risk factors for posttransplant skin cancer occurring in a group of organ transplant recipients who received a primary organ transplant between 2003 and 2008. The study included 10,649 recipients identified from the Organ Procurement and Transplantation Network database. Follow-up periods were 5 and 10 years.

During the study period, 8% of participants developed skin cancer. The overall incidence of posttransplant skin cancer was 1,408 per 100,000 person-years. Squamous cell carcinoma was the most commonly occurring cancer, with an incidence of 1,328 per 100,000 person-years, followed by melanoma (122 per 100,000 person-years), and Merkel cell carcinoma (4 per 100,000 person-years).

“By comparison, the US general adult population age-adjusted incidence rate of squamous cell carcinoma is 38 per 100,000. The incidence rate of melanoma was…also elevated compared with the general population rate of 9 to 18 per 100,000,” the researchers wrote. “To further put these numbers into context, the skin cancer incidence rate in organ transplant recipients is nearly 5 times the rate of all cancers combined in the overall US population (448.7 per 100,000).”

The incidence rate for skin cancer was highest among patients who received thoracic transplant (2,426 per 100,000 person-years), followed by white individuals (2,039 per 100,000 person-years), patients 50 or older at transplant (2,032 per 100,000 person-years), men (1,718 per 100,000 person-years), and those transplanted in 2008 vs 2003 (1,651 per 100,000 person-years).

“The corresponding incidence rates for these groups underscore the magnitude of these effects: in whites the incidence rates (per 100,000) was 2,039, a 22-fold higher rate than in nonwhites; for men, patients 50 years or older at transplant, and thoracic organ transplant recipients, the incidence rates were 1.7-fold to 3-fold higher than for women, patients younger than 50 years at transplant, or abdominal organ transplant recipients, respectively.”

Many of these factors were also identified as having a significant association with developing skin cancer, including male sex (adjusted hazard ratio [HR], 1.61; P < .001), thoracic organ transplantation (HR, 1.51; P < .001), white race (HR, 7.79; P < .001), age (HR, 2.65; P < .001), and year of transplant (HR, 1.59; P < .001).