2021 Volume 36 Issue 3 Pages 197-202
We report the case of a 33－year－old Japanese male who had previously been diagnosed with malignant melanoma on his back and left big toe, with new pigmented macules on his back and left lower leg being excised. Histopathological examination had revealed malignant melanoma（superficial spreading, in situ). His family history was significant for malignant melanoma in his mother and in two of his great－aunt’s children ; therefore, we diagnosed familial malignant melanoma.
In Europe and the United States, various genetic mutations, including CDKN2A, CDK4, BAP1, POT1, and TERT, have been reported as causes of familial malignant melanoma. In Japan, seven families have reported familial malignant melanoma, two of which underwent a genetic analysis with no reports of pathogenetic mutations. Although we performed genetic analysis by whole－exome sequencing, no pathogenic mutation was found here either. Future analyses are needed to clarify possible genetic mutations and their trends in familial malignant melanoma in Japan. [Skin Cancer (Japan) 2021 ; 36 :197－202]
