A LONG-TERM ANALYSIS OF 620 PATIENTS WITH MALIGNANT-MELANOMA AT A MAJOR REFERRAL CENTER

Background. A univariate and multivariate statistical analysis of a si ngle surgeon's experience with resectable malignant melanoma during 26 years (November 1970 to August 1996) was conducted. Methods. Six hund red twenty consecutive patients were registered. Univariate analysts o f disense-fr ee survival (DFS) and melanoma survival (MS) was calculat ed by the Kaplan-Meier method and correlated to American Joint Committ ee on Cancer stage, thickness, ulceration, site, lymph node involvemen t, age, sex, type, and excision margins. Linear trends, log-rank test, and pairwise comparisons were used to discriminate differences in sur vival curves. A Cox proportional hazards model was used for multivaria te analysis and determination of relative risk. Results. Univariate an alysis of stage, thickness (in millimeters), ulceration, lymph node in volvement, age, type, and margins of excision were predictive of DFS ( 5 years, 85.7%; 10 years, 82.5%) and MS (5 years, 92.2%; 10 years, 87. 8%) (P < .01). Multivariate analysis revealed correlations with thickn ess, ulceration, and age in predicting DFS (relative risk = 2.75, 2.21 , and 1.47, respectively) and MS (relative risk = 2.66, 2.47, and 1.48 , respectively). The 5-year MS rate was 73.3% and 93.3% for patients w ith positive and negative lymph nodes, respectively. Of 133 patients w ho underwent lymph node dissection, 28 (21.1%) had nodal metastases. P atients with primary melanomas thicker than 4 mm had 50% metastatic in volvement of their lymph nodes. Conclusions. Our findings reveal that thickness, ulceration, and age are the most important predicting facto rs in DFS and MS. The data support including ulceration and age in mod ifying America joint Committee on Cancer staging for melanoma.