Abstract: Objective To investigate the clinical outcomes of surgical excision combined with recombinant interferon alpha-2b in the treatment of acral malignant melanoma （MM）. Methods Fifteen patients with acral MM admitted to the department since 2004 were recruited into this study. The tumors varied from 1.8 mm to 3.9 mm in invasion depth. Thin tumors with an invasion depth of 1.8 - 2.0 mm were excised with a margin of 1cm beyond the tumors, and those with an invasion depth of 2.0 - 3.9 mm were excised with a margin of 2 cm beyond the tumors. After excision, 4 cases of minor excision were sutured directly, 10 cases of large excision were repaired with adjacent skin grafts and flaps, 1 patient with the involvement of the first metatarsophalangeal joint underwent toe amputation followed by the repair of planta wound surface with the remaining skin on the dorsa of toes. Patients received intramuscular recombinant interferon alpha-2b for 3 months （3 million units daily for the first 3 days and 6 million units for the remaining days） following operation. Results There were 6 cases of MM in situ and 9 cases of invasive MM in this study. All the skin grafts and flaps survived. Within the 3-year follow up, relapse was observed only in 1 patient with invasive MM. Recovery was achieved in the functions of feet in all patients. Conclusion The excision of tumors with a margin determined by tumor thickness plus intramuscular interferon alpha-2b may improve the survival of patients with cutaneous MM in planta pedis with avoidance of amputation.

Key words: acral malignant melanoma, interferon, operation, biotherapy