Number of primary melanomas is an independent predictor of survival in patients with metastatic melanoma.

BACKGROUND: A history of multiple primary melanomas (PMs) has been associated with improved survival in patients with early stage melanoma, but whether it also is correlated with survival in patients with metastatic melanoma is unknown. The authors sought to address the latter question in the current study. METHODS: Patients with metastatic melanoma diagnosed at the Melanoma Institute Australia between 1983 and 2008 were identified. Overall survival (OS) was calculated from date of first distant metastasis. Survival analysis was performed using the Kaplan-Meier method, log-rank tests, and multivariate Cox proportional hazards models. RESULTS: Of 2942 patients with metastatic melanoma, 2634 (89.5%) had 1 PM and 308 (10.5%) had >1 PM. Factors that were associated independently with shorter OS were site of metastasis, including the brain (hazard ratio [HR], 2.41; 95% confidence interval [CI], 2.07-2.81; P < .001) and non lung viscera (HR, 1.92; 95% CI, 1.67-2.22; P < .001, vs lymph node/subcutaneous/soft tissue), age >60 years (HR, 1.23; 95% CI, 1.12-1.36; P < .001), shorter disease-free interval from PM to first distant metastasis (≤ 12 months vs >36 months: HR, 1.62; 95% CI, 1.39-1.89; P < .001), and fewer PMs (1 vs >1; HR, 1.26; 95% CI, 1.08-1.47; P = .004). CONCLUSIONS: A history of multiple PM was an independent predictor of improved survival for patients with metastatic melanoma. The results indicate that a history of multiple PMs should be incorporated into multivariate analyses of prognostic factors and treatment outcomes.

Treatment and prognostic significance of positive interval sentinel nodes in patients with primary cutaneous melanoma.

BACKGROUND: Interval sentinel nodes (SNs) are lymph nodes receiving direct lymphatic drainage from a primary site and lying between the tumor and a recognized node field. It is not clear what further nodal surgery should be performed when interval nodes are found to contain micrometastatic disease. In this study, the incidence, location, and treatment of interval SNs in melanoma patients were analyzed to develop recommendations regarding the treatment of patients with interval SNs. METHODS: A retrospective review was undertaken of all patients with primary cutaneous melanoma who underwent lymphoscintigraphy at a single institution between 1992 and 2007. Data concerning the primary melanoma, location of SNs, treatment and survival were analyzed. RESULTS: Of 4895 patients who had a lymphoscintigram during the study period, 442 (9.0%) had an interval SN identified on lymphoscintigraphy. Interval SNs occurred significantly more often in patients with melanomas on the posterior trunk than in those with melanomas at other sites (P<0.001). A total of 197 patients (44.6%) with an identified interval SN underwent excision biopsy of the node. Of the 16 patients found to have metastatic melanoma in their interval SN, four also had negative SNs in a recognized lymph node field, and no other positive nodes were found on completion lymphadenectomy. CONCLUSIONS: Interval SNs are present in approximately 1 in 10 melanoma patients but are about half as likely to contain metastases as SNs in recognized node fields. If a positive interval SN is found, completion lymphadenectomy of the recognized lymph node field is only recommended if a SN in this field is also positive.

Total sentinel lymph node tumor size predicts nonsentinel node metastasis and survival in patients with melanoma.

INTRODUCTION: In patients with a primary melanoma ≥1.0mm in Breslow thickness, the rate of metastasis to regional lymph nodes, as determined by sentinel node biopsy (SLNB), is approximately 20%. Among the patients with a positive SLNB result, however, only approximately 20% have tumor identified in additional non-SLNs. Therefore, many melanoma patients are still subjected to the morbidity of a complete lymph node dissection (CLND) without obvious benefit. In the current study, we analyzed the clinical and pathologic features of melanoma patients with positive SLNBs treated at the Melanoma Institute Australia. The aim was to correlate clinical and pathologic features of both the primary melanoma and the SLN metastases, including total SLN metastasis, with non-SN metastasis and (disease specific and overall) survival. METHODS: Total SLN tumor size was obtained by adding the largest diameters of all individual metastatic deposits within the SLN. Clinicopathological variables analyzed included patient age at the time of diagnosis, primary tumor characteristics (histologic type, Breslow thickness, ulceration, mitotic rate, site of primary tumor), and SLNB characteristics (date of SLNB procedure, location of LN field, number of draining LN fields, number of SLNs harvested, number of positive SLNs, size of largest metastatic deposit, total metastatic deposit size, location of metastasis within the SLN, extra nodal extension (ENE), and number of metastatic deposits within the SLN). The correlation between each of the predictor variables and outcome was determined by univariate analysis. The predictor variables that correlated with NSLN metastasis with a p value < 0.10 on univariate analysis were then entered into a multivariate model. RESULTS: There were 606 patients with a positive SNSNB result who proceeded to a CLND. The median number of NSNs in CLND specimens was 18 and the median number of positive NSLNs was 2.68. Of the patients with SN metastasis, 23.5% also had NSLN metastasis on CLND. Total SLN tumor size was significantly correlated to NSLN metastasis, melanoma-specific survival and overall survival on both univariate and multivariate analyses. CONCLUSION: Total SN tumor size predicts the likelihood of non-SLN metastasis, and also predicts survival outcome.

Re-evaluation of a scoring system to predict nonsentinel-node metastasis and prognosis in melanoma patients.

BACKGROUND: We previously developed a scoring system based on patient age and total sentinel node (SN) tumor size to predict nonsentinel node (NSN) metastasis. The score relied on the cutoff values of 55 years for age and 5 mm total SN tumor size to stratify SN-positive patients into 3 categories. Its validity, however, remains in doubt given that it was developed by retrospective review of a single, relatively small cohort of SN-positive melanoma patients. The purpose of this study was to validate this scoring system and to determine its value in predicting patient survival. STUDY DESIGN: A review of melanoma patients who had undergone sentinel node biopsy and completion lymph node dissection (CLND) at the Melanoma Institute Australia from June 1992 until April 2009 was undertaken. The significance of the correlation of each of the score variables (age and total SN tumor size) with NSN metastasis, melanoma-specific survival, and overall survival was tested. Cox logistic regression analysis was used to determine the degree of correlation of the score system to each of the 3 outcomes. RESULTS: Six hundred six SN-positive patients were identified and included in this study. The score system did not significantly correlate with NSN metastasis (p = 0.1049). However, it did significantly correlate with both overall survival (p < 0.0001) and disease-specific survival (p = 0.0014). CONCLUSIONS: Our results revealed that the previously developed scoring system does not predict NSN metastasis; however, it was found to be a powerful predictive tool for overall and disease-free survival in SN-positive melanoma patients.