Multiple inguinal and pelvic lymph node metastases of malignant melanoma of the heel identified by common iliac lymphadenopathy.

It is extremely rare that swelling of pelvic lymph nodes is found when inguinal lymph nodes contain only a microscopic amount of disease without enlargement. A 69-year-old woman with malignant melanoma of the heel was treated with a wide, local excision. About four years after the initial operation, a left common iliac node was enlarged although all lymph nodes in the obturator, external iliac and inguinal regions were not enlarged. Rapid pathological examination of the resected swollen lymph nodes revealed involvement of malignant melanoma, and left pelvic and groin dissection was undertaken. Histologically, multiple lymph node metastases were found in the common iliac, obturator, external iliac and inguinal regions. This case indicates that sentinel lymph node biopsy may be worth considering even for stage IA malignant melanoma of the lower extremity.