Distribution of lymph node metastases in the malignant melanoma of the trunk.

Of 1217 patients with malignant melanoma treated at the Institute of Oncology in Warsaw during the period from 1947 to 1982 there were 135 patients (11.1%) with malignant melanoma of the trunk. A retrospective analysis of this group of patients has been carried out in order to study the routes of lymphatic dissemination of melanoma. 14 patients were excluded from this study due to the lack of sufficient information. In the group of 121 patients considered, lymph node metastases were found in 82 patients (67.7%). In 12 patients (9.9%), blood-borne metastases were found as the first sign of dissemination. In 26 patients the primary melanoma was located in the midline skin along the spine at the back, on the white line and its extension at the front, and in a 6-cm-wide horizontal strip of skin at the level of the iliac crest. Among this group in 9 individuals simultaneous metastases to two different lymph regions were found; in 7 patients the first metastases occurred in distant lymph nodes without metastases to the nearest ones. In the remaining 56 patients the primary melanoma was located on the skin of the trunk elsewhere. In 49 of these patients (87.5%) metastases were found in the regional lymph nodes, while in 7 they were found in distant lymph nodes. 21/121 (17.3%) have survived longer than 5 years without symptoms of disease.