Level of fluorodeoxyglucose uptake predicts risk for recurrence in melanoma patients presenting with lymph node metastases.

BACKGROUND: The incidence of malignant melanoma has increased. Identification of additional prognostic factors may allow the development of individualized strategies. This multivariate analysis was undertaken to evaluate the potential role of the standard uptake value (SUV) in predicting disease-free and overall survival in melanoma patients with lymph node metastases.
METHODS: All melanoma patients with palpable lymph node metastases who where referred for a fluorodeoxyglucose positron emission tomography scan were eligible. The SUV in the lymph node metastasis was calculated. Data were analyzed (Kaplan-Meier), and differences in cumulative survival and the disease-free rate were assessed (log-rank test). Univariate and multivariate analyses (Cox proportional hazard model) were performed to determine independent prognostic factors.
RESULTS: There was no statistical difference in survival for the 38 patients with a high or low SUVmean (P = .11). However, a significant difference was found in disease-free survival (P = .03). Ulceration of the primary melanoma (P = .023) was an independent predictor of survival. For the disease-free survival, multivariate Cox regression showed adjuvant radiation (P = .001), localization of the primary melanoma (P = .017), and a high SUVmean (P = .009) as independent prognostic factors.
CONCLUSIONS: Disease-free survival of melanoma patients was prolonged in those with a low SUVmean value (P = .03) in their lymph node metastasis, as compared with those with a high SUVmean. However, this difference was not found for overall survival. In multivariate analysis, high SUVmean was an independent prognostic factor (P = .009) for disease-free survival. Prospective research should determine whether patients with a high FDG uptake in melanoma lymph node metastases could benefit from adjuvant radiation treatment or chemotherapy.