Nodular melanoma in 62 Japanese patients: influence of initial surgical treatment on local recurrence and prognosis.

The incidence of malignant melanoma is much lower in Japanese than in Caucasians, and the commonest type of melanoma in Japanese is acral lentiginous melanoma (ALM). In contrast to the improved prognosis noted in ALM, it is now of increasing concern that there is a rise in both the frequency and mortality of nodular melanoma. During the 25 years from 1970 to 1994, we observed 190 patients with melanoma, including 62 nodular melanomas and 96 ALM, at the Department of Dermatology, Tohoku University Hospital, Sendai, Japan. We retrospectively reviewed the recurrence and survival rates of nodular melanoma observed. The proportion of nodular melanoma, once comprising only 24% of all melanomas, showed a sharp increase to 40% after 1982. The anatomical sites of the primary tumor were the hands and feet (29%), extremities excluding hands and feet (27%), head and neck (23%), and trunk (21%). Comparison of the stages of nodular melanoma when diagnosed showed that the proportion of stage III remained highest throughout the whole period, but that of stage II melanomas increased after 1982. After treatment, local recurrence occurred far more frequently in nodular melanoma (19%) than in ALM (1%). The prognosis of nodular melanoma was also less favorable than that of ALM, although it slightly improved after 1982; the 5-year survival rates before and after 1982 were 34 and 50%, respectively. Twenty-eight patients with nodular melanoma had underwent simple excision or incisional biopsy of the primary tumor at another institution and were later referred to us for further intensive care or for the treatment of local recurrence and/or metastases.(ABSTRACT TRUNCATED AT 250 WORDS)