Treatment Outcome and Prognostic Factors for Malignant Skin Melanoma Treated with Radical Surgery

To assess the treatment outcome in patients with malignant skin melanoma and prognostic factors for distant metastases (DM), disease-free survival (DFS) and overall survival (OS).

A retrospective analysis was conducted on 113 patients with malignant skin melanoma (60 females, 53 males, average age-55 years) who were treated surgically. Primary treatment consisted of local excision. In 12 cases, it was accompanied by lymph node excision. In 93 (82%) cases, radicalization was necessary, which was either local only (19 cases) or accompanied by lymph node surgery/biopsy (74 cases). Possible prognostic factors such as Clark's stage and Breslow's depth of invasion, ulceration, average tumor dimensions, lymph nodes metastases (pN+), gender, tumor location and primary excision margins were considered.

In 51 (45%) cases, treatment failure occurred. The 5-year DM rate was 47%, the 5-year DFS was 38%, and the 5-year OS was 56%. In the univariate analysis, the important factors with respect to at least one endpoint included Clark's stage, Breslow's depth of invasion, ulceration, average tumor dimensions, lymph nodes metastases, gender and primary tumor localization. The presence of metastasic nodes was the most important prognostic factor, with a 5-year DM rates of 30% for pN(-) and 76% for pN(+) and a 5-year DFS and OS of 56% and 76% for pN(-) and 13% and 24% for pN(+), respectively. The average tumor dimension was independently significant for DFS and OS, with 5-year rates of 69% and 80% for ≤1 cm, 28% and 53% for 1-2 cm, and 18% and 30% for >2 cm, respectively. Tumor location was also significant for DM and OS, with 5-year rates of 69% vs 33% and 41% vs 66% for trunk vs other locations, respectively.

The natural course of a malignant skin melanoma treated radically is disadvantageous, with unsuccessful outcome in nearly half of the cases. Common clinical factors, such as Clark's tumor stage, Breslow's depth of invasion and the presence of metastatic nodes, have high prognostic significance. The size and location of the primary lesion may be considered independent prognostic factors. The most important negative prognostic factor is the presence of metastatic regional lymph nodes. Only one quarter of patients with metastases in lymph nodes survive 5 years from primary surgery.