Nevi and Melanoma: Lessons from Turner’s Syndrome

Abstract

Females with Turner’s syndrome (TS) have a markedly increased number of cutaneous nevi. While this is a well-recognized risk factor for cutaneous melanoma (CM), the incidence of this tumor in TS and the implications for our understanding of nevi and melanoma have not previously been considered. Here we report a case of an anorectal melanoma in a woman with TS and a review of the literature. Overall, there appears to be a lower than expected incidence of CM. Possible explanations are discussed and in particular the possible relationship between sex hormones and melanoma development as these girls fail to undergo normal pubertal development. Further study of this syndrome may provide important insights into the genetic factors involved in normal melanocyte and nevus development, the potential influence of sex hormones on melanoma development and the relationship between the presence of nevi and the risk of developing CM.

Turner's syndrome in dermatology

“…1,2 The defining clinical triad of impaired sexual development, webbed neck, and cubitus valgus was first described in the English-language literature by Turner 3 in 1938, with ovarian failure and streaked gonads noted in 1944. 4 Ullrich 5 in 1930 and Bonnevie 6 in 1934, described similar clinical findings in a young girl and mouse, respectively, thus, also having their names ascribed to this disorder.…”

“…103,104 Interestingly, despite the prevalence of nevi, the incidence of melanoma appears to be markedly reduced in TS. 2 Only 5 cases of TS with unusual melanomas appear in the world literature, including ocular choroidal melanoma in a TS mosaic (45X/46XX), 105 lentigo maligna melanoma in a woman with 45X TS and more than 200 nevi, 97 anorectal malignant melanoma in a young women with TS and few benign nevi, 2 and 2 cases of advanced metastatic melanoma, 1 with unknown primary. 106,107 An unusual combined compound nevus/Spitz's nevus has also been reported in an 11-year-old with TS mosaic with 45 X/47XXX karyotype.…”

“…108 Given the prevalence of nevi in TS, the unexpectedly low incidence of melanoma suggests that a protective tumor suppressive factor may be operating. 2 Several syndromes, including fragile X syndrome and Down syndrome, also have a significantly reduced overall tumor incidence, with chromosomal deletion syndromes suggested to offer some unknown protection against carcinogenesis. 109 The cause of increased nevi in TS remains unknown.…”

Lymphatic, tooth and skin manifestations in Turner syndrome

“…[11], but this has been disputed by others [12]. Despite the increased number of nevi, there does not appear to be an increased risk of melanoma [13].…”

Turner’s Syndrome, Melanocytic Nevi and Melanoma

“…I read with interest the paper of Gibbs et al [1] concerning a case of Turner's syndrome associated with mucosal melanoma. In their discussion, the authors point to the discrepancy between the large number of melanocytic nevi usually observed in sufferers from Turner's syndrome and the incidence of malignant melanoma which in these patients is deemed to be lower than expected.…”