番茄社区

A patient's risk of skin cancer appeared to soar after getting an organ transplant, a large retrospective study found.

Skin cancer occurred at a rate of , with some cancers more common than others, according to data published online in JAMA Dermatology:

• Squamous cell carcinoma: 1,328 per 100,000 person-years
• Melanoma: 122 per 100,000 person-years
• Merkel cell carcinoma: 4 per 100,000 person-years

"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 U.S. population (448.7 per 100,000)," wrote , of University of California San Francisco (UCSF), and colleagues.

"A follow-up goal of this study is to develop a prediction tool for post-transplant skin cancer," they continued. "To our knowledge, Germany executed the first nationwide skin cancer screening program for the general population in 2008; its effectiveness in reducing the mortality and morbidity of skin cancer is under evaluation."

"Physicians should refer solid organ transplant recipients for regular skin cancer screening by a dermatologist. Recipients should be sure to follow sun protection measures, including avoiding prolonged exposure to bright sunlight, wearing protective clothing, and using sunscreen," suggested , of the National Cancer Institute in Rockville, Md., who was not involved in the study.

He said he agreed with the authors' recommendations, as did , chief of transplant surgery at UCSF.

"Consideration should be given to the use of vitamin B3 (niacinamide) in high-risk patients to prevent skin cancers, as this has shown to be effective in non-transplant patients. Side-effects are minimal and cost is low," he commented in an email to 番茄社区. Roberts was not involved in the study.

Arron's group accessed the U.S. Organ Procurement and Transplantation Network (OTPN) database to find information on adult recipients of a primary transplant performed in 2003 or 2008. Cases involving solid organ transplants -- excluding intestinal transplants -- were included (n=10,649).

Transplant recipients averaged age 51 at the time and consisted of 64% men.

Predictors of post-transplant skin cancer were:

• Pre-transplant skin cancer: hazard ratio 4.69 (95% CI 3.61-6.09)
• Heart and/or lung transplant: HR 1.51 (95% CI 1.26-1.82)
• Male sex: HR 1.61 (95% CI 1.34-1.89)
• White race: HR 7.79 (95% CI 5.34-11.37)
• Age at transplant 50 years or older: HR 2.65 (95% CI 2.12-3.21)
• Transplant in 2008 versus 2003: HR 1.59 (95% CI 1.33-1.91)

Regarding the increased observations of skin cancer in 2008 compared with 2013, according to Engels, "this trend could represent an artifact of screening or improved record keeping, but it is concerning if it is a real increase."

"The main limitation of this study was the imperfect capture of outcome data," according to the authors. "The primary reason for missing skin cancer data was the failure to have a dermatologic history noted in the medical record. This may occur if patients were followed by dermatologists in the community and did not report their skin cancers to the transplant team."

They maintained that they addressed this limitation by performing several sensitivity analyses using methods to address the gaps in their records.

Also missing in the OTPN database are data on the duration and dosage of certain immunosuppressive agents such as azathioprine (Imurann) that have been known to increase the risk for skin cancer.

"The utility of the data presented is to inform risk prediction at the time of transplant, before post-transplant drug exposures. Future research is needed to determine whether skin cancer risk can be mitigated through the optimization of immunosuppressive regimes," the authors wrote.

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