Sentinel Node Tumor Burden According to the Rotterdam Criteria Is the Most Important Prognostic Factor for Survival in Melanoma Patients

SUMMARY BACKGROUND DATA: The more intensive sentinel node (SN) pathologic workup, the higher the SN-positivity rate. This is characterized by an increased detection of cases with minimal tumor burden (SUB-micrometastasis 1 mm) maximum diameter of the largest metastasis. The predictive value for additional nodal metastases in the completion lymph node dissection (CLND) and disease outcome as disease-free survival (DFS) and overall survival (OS) was calculated. RESULTS: In 388 SN positive patients, with primary melanoma, median Breslow thickness was 4.00 mm; ulceration was present in 56%. Forty patients (10%) had metastases 1.0 mm (P < 0.001). SN tumor burden increased significantly with tumor thickness. When the cut-off value for SUB-micrometastases was taken at <0.2 mm (such as in breast cancer), the survival was 89%, and 10% had additional non-SN nodal positivity. CONCLUSION: This large multicenter dataset establishes that patients with SUB-micrometastases <0.1 mm have the same prognosis as SN negative patients and can be spared a CLND. A <0.2 mm cut-off for SUB-micrometastases does not seem correct for melanoma, as 10% additional nodal positivity is found.