Dermoscopic Features of Melanomas in Organ Transplant Recipients.

Abstract

1https://www.medicaljournals.se/acta/content/abstract/10.2340/00015555-3264 Melanomas are highly immunogenic tumours, and a well-orchestrated immune response is important for melanoma control (1). In order to avoid the rejection of a transplanted organ, lifelong immunosuppressive treatment is instrumental for organ transplant recipients (OTRs). In a systematic meta-analysis including 12 studies, a 2.4-fold (95% confidence interval (95% CI) 2.0–2.9) risk increase for melanoma in OTRs was observed compared with the general population (2). Although OTRs have an enhanced relative risk of melanoma, their occurrence in absolute terms is remarkably rare. To exemplify this, in a Swedish nationwide retrospective cohort study, including 10,476 OTRs in the time period 1970–2008, only 52 malignant melanomas were diagnosed in 51 patients, standardized incidence ratio (SIR) 2.2 (95% CI 1.7–2.9) (3). In a retrospective Norwegian investigation, including 2,561 heart and kidney transplant recipients (15,123 person-years), 12 cases of melanoma were observed when only 3.56 were expected (SIR 3.4; 95% CI 1.7–5.9) (4). In another retrospective Swedish investigation, no more than 49 cases among OTRs were observed in the time period 1984–2008. Importantly, the melanomas in the OTR group had more advanced disease at diagnosis and an increased melanoma-specific mortality (5). Thus, diagnosing melanomas in OTR at an early stage is essential. Dermoscopy is a valuable tool for assessing pigmented skin lesions and can improve the early detection of melanomas compared with the naked eye (6). Little is known about the dermoscopic criteria of melanomas arising in OTRs. The following retrospective study was performed as an exploratory investigation, in order to evaluate whether melanomas in this patient group demonstrate a different set of dermoscopic characteristics compared with melanomas in ageand sex-matched individuals.