Prognostic factors in young women with cutaneous melanoma.

Background: Gender is an established prognostic factor in cutaneous melanoma; women as a group have a better overall prognosis than men. However, the investigators hypothesized that melanoma in young women may have distinct clinicopathologic features and biologic behavior compared with melanoma in older women, possibly related to tanning bed use and excessive acute episodes of sun exposure.

Methods: A retrospective analysis was performed of a large multicenter study that accrued patients between 1996 and 2003 and included patients aged 18 to 70 years with cutaneous melanoma ≥1 mm Breslow thickness and no evidence of regional or distant metastatic disease. All women with follow-up data were included. Univariate and multivariate analyses as well as Kaplan-Meier (KM) analysis were performed to test for differences in clinicopathologic variables, disease-free survival (DFS), and overall survival (OS) between female patients ≤40 and >40 years of age.

Results: A total of 1,056 female patients were divided into 2 groups: those >40 years of age (n = 757 [71.7%]) and those ≤40 years of age (n = 299 [28.3%]). Overall, there were no differences in Breslow thickness, ulceration, or sentinel lymph node status between groups. Compared with older women, younger women were more likely to have truncal melanomas (39.5% vs 29.5%, P = .0017) and less likely to have regression of the primary tumor (6.4% vs 11.5%, P = .0208). The mean number of sentinel lymph nodes removed was 2.82 for younger women and 2.29 for older women (P < .0001). Multivariate analysis revealed that Breslow thickness, ulceration, and tumor-positive sentinel lymph node were associated with worse DFS in both the younger and older groups; truncal location was associated with worse DFS in the younger group only. The same factors were predictive of OS in both groups, except that ulceration was not significant in the younger patient group. In the younger patient group, the 5-year KM DFS rates were 78.1% for truncal melanomas and 92.5% for nontruncal melanoma locations (P = .0009); the corresponding 5-year KM OS rates were 76.6% and 93.9% (P = .0003). In the older patient group, the 5-year KM DFS rates were 84.1% for truncal and 82.8% for nontruncal melanomas (P = NS), and the corresponding 5-year KM OS rates were 81.6% and 87.5% (P = .0049).

Conclusions: Although women with cutaneous melanoma tend to have a better prognosis than men, women ≤40 years of age with primary melanoma of the trunk may represent a subgroup at higher risk for disease recurrence and metastasis.