566 stage-II melanoma patients treated at the National Cancer Institute of Milan, Italy, were analyzed to evaluate the prognosis. Among the criteria considered, four were significantly associated with survival when considered as single factors: growth pattern, levels of invasion, the number of involved lymph nodes, and the extent of metastatic growth. As regards growth pattern, the observed 5-year survival rates were 41.9% for superficial spreading melanoma and 20.5% for nodular melanoma (P = 10−3). As regards levels, the 5-year survival rates were as follows: level II, 20.9%; level III, 33.1%; level IV, 43.2%; level V, 10.2% (P = 10−3). Patients with a partial node metastasis had 64.5% 10-year survival, while those with extension beyond the capsule had 32.6% 10-year survival (P = 10−9). Patients with one metastatic node had 43.4% 10-year survival, and patients with three or more positive nodes had 26.0% 10-year survival (P = 10−9). Multifactorial analysis shows that growth pattern and extent of node metastases significantly affect survival (P =10−2 and P = 10−4, respectively) while the number of involved nodes turns to borderline P-value (0.051) and the levels are no longer significant (P = 0.4).