Abstract
A 66-year-old woman who had been diagnosed with left inguinal metastasis of malignant melanoma was referred to our hospital. She presented with a black nodule on her waist that appeared to have regressed spontaneously. Histologic examination revealed many nests of melanoma cells in the epidermis and upper dermis. No melanoma cells were detected in the area of transition to the clinically apparent area of depigmentation, although, interestingly, there were a number of dermal melanophages as well as the underlying melanoma nests. Adjacent to the melanoma on her waist, there was a giant congenital nevus (GCN), which had had a uniformly dark brown color since birth. Regression of the GCN occurred simultaneously with the discovery of melanoma. At the time of her first visit to our hospital, many small black spots on pale brown macula were evident. It was conceivable that an immune response to melanoma cells might cross-react with melanocytic antigen of GCN. She had systemic metastasis of melanoma in bilateral cervical lymphnodes, periaortic lymphnodes and left inguinal lymphnodes. The level of tumor marker 5-S-CD was very high. Excision of the primary lesion and cervical and inguinal lymphadenectomy were performed. Subsequently, DAC-Tam therapy was initiated. After three courses of chemotherapy, the involvement of periaortic lymphnodes disappered and the 5-S-CD level decreased to the normal range. Monthly administration of interferon beta was continued. As of this writing, no recurrence or metastasis has been noted for 15 months after cessation of DAC-Tam therapy.
