Department of Dermatology, Chiba University Graduate School of Medicine, Chiba, Japan.
Int J Dermatol. 2010 Dec;49(12):1362-7. doi: 10.1111/j.1365-4632.2010.04602.x.
Malignant melanomas clinically and/or histologically associated with melanocytic nevi have been reported worldwide. Approximately 20% of malignant melanomas in Caucasians, most of which are found on the trunk and proximal extremities, develop in association with pre-existing melanocytic nevi. In Japan, however, over half of all melanomas are acral lentiginous melanomas (ALMs) on the hands and feet; melanomas on sun-exposed areas are seen less frequently in Japanese people than in Caucasians. As ALMs are not usually accompanied by melanocytic nevi and there have been no reviews of the literature or statistical data regarding Japanese cases of melanomas with melanocytic nevi, dermatologists in Japan have few opportunities to see melanomas associated with pre-existing melanocytic nevi.
Here we report a case of a superficial spreading melanoma that was formed on a melanocytic nevus on the trunk, and we review for the first time the case reports from the Japanese literature.
With regard to the reported cases, melanomas associated with melanocytic nevi were mainly superficial spreading melanomas and nodular melanomas on the trunk or extremities; ALMs were rarely associated with nevi, indicating a trend similar to that observed in Caucasians. These findings suggest that the low frequency of associations between melanomas and melanocytic nevi in Japan reflects racial differences in the frequencies of each type of melanoma.
在全球范围内都有报道称，临床上和/或组织学上与黑色素痣相关的恶性黑色素瘤。在白种人中，约 20%的恶性黑色素瘤与先前存在的黑色素痣有关，其中大多数发生在躯干和近端肢体上。然而，在日本，所有黑色素瘤中超过一半是手足的肢端雀斑样黑色素瘤（ALM）；与白种人相比，日本人较少在阳光照射的部位出现黑色素瘤。由于 ALM 通常不伴有黑色素痣，而且对于日本伴有黑色素痣的黑色素瘤病例也没有文献综述或统计数据，因此日本的皮肤科医生很少有机会看到与先前存在的黑色素痣相关的黑色素瘤。
在这里，我们报告了一例发生在躯干黑色素痣上的浅表扩散性黑色素瘤，并首次对来自日本文献的病例报告进行了回顾。
就报告的病例而言，与黑色素痣相关的黑色素瘤主要是发生在躯干或四肢的浅表扩散性黑色素瘤和结节性黑色素瘤；肢端雀斑样黑色素瘤很少与痣相关，这表明与白种人观察到的趋势相似。这些发现表明，日本黑色素瘤与黑色素痣之间的低关联频率反映了每种黑色素瘤类型的种族差异。
