Melanoma in organ transplant recipients: The old enemy finds a new battleground

Abstract

Population registry data and published studies have demonstrated that melanomas in the transplant population occur 1.6-2.5 times more commonly compared with the general population. Studies examining possible risk factors have suggested that in this patient population, there is an increased number of melanocytic naevi. Whether this phenomenon is aetiologically related to subsequent melanoma development is currently unclear. Only one study examined the prognosis of melanomas in this population. The Israel Penn International Transplant Tumor Registry has collated patient data voluntarily submitted by transplant physicians throughout the USA since 1968. Analysis of melanomas in this study found that approximately half were Breslow thickness >1.51 mm. Overall, there was a high rate of nodal and distant metastases, with poorer 1-, 3- and 5-year survival rates compared with the general population. There is a paucity of good-quality evidence regarding melanoma in organ transplant recipients. Further research involving international collaborative trials, particularly on risk factors and the prognosis of melanomas in this population, could present a more substantial evidence base from which treatment guidelines based on data could be developed.

Melanoma and Rituximab: An Incidental Association?

“…Four patients had early metastatic disease and 3 died of their melanoma. These histological and evolutionary data suggest that rituximab-associated melanomas could potentially be more aggressive melanoma forms, as reported in patients with organ transplants [6]. The underlying pathology does not however seem to be a determining factor.…”

Melanoma in Immunosuppressed Patients

“…23,24,38 All things considered, although the majority of these large population-based studies of OTRs have shown an increased risk of melanoma, the relative risk is still much lower than that of nonmelanoma skin cancers. 40,41 By comparison, the incidence of nonmelanoma skin cancers posttransplant is increased 50-to 250-fold for squamous cell carcinoma and 10-fold for basal cell carcinoma. 24,26,42 Melanoma Before Transplant The majority of research shows no strong evidence supporting an increased risk of melanoma recurrence in patients who have a history of melanoma before transplant.…”

“…Some studies have documented findings about survival, metastatic potential, and other aspects of the clinical course. 6,25,47 De novo melanomas tend to develop 3 years posttransplant or later, 40 with reports ranging from 14 to 236 months. 29 The mean time for melanoma development in the OTR population is 61 months posttransplant, 44 with some studies documenting a range of 40 to 132 months.…”

“…86 Other recommendations include avoiding transplant in cases in which patients have distant metastases or extensive regional metastases. 40 Otherwise, melanomas in OTRs without nodal metastases can be treated with the standard protocols outlined for the general immunocompetent population. 40 With the new developments in terms of melanoma therapy with immunomodulatory agents-namely, vemurafenib and ipilimumab-the future of melanoma treatment is prone to change.…”

“…40 Otherwise, melanomas in OTRs without nodal metastases can be treated with the standard protocols outlined for the general immunocompetent population. 40 With the new developments in terms of melanoma therapy with immunomodulatory agents-namely, vemurafenib and ipilimumab-the future of melanoma treatment is prone to change. However, studies have shown that the rate of BRAF sequence variations in melanocytic tumors in immunosuppressed patients, particularly OTRs, is less frequent than in control lesions.…”