Outcome of Melanoma Patients Who Did Not Proceed to Sentinel Node Biopsy After Preoperative Lymphoscintigraphy

At our institution, a planned sentinel node biopsy (SNB) procedure is occasionally canceled after preoperative lymphoscintigraphy. This study reports the frequency of this, the reasons, and the management and outcomes of these patients.

All patients with clinically localized cutaneous melanoma treated at Melanoma Institute Australia between 2000 and 2009 whose planned SNB procedure was not undertaken after lymphoscintigraphy were included in this retrospective study.

Of the 3148 patients in whom the procedure had been planned, 203 patients (6.4 %) did not have a SNB. The main reason for not proceeding with SNB (in 84 % of cases) was the lymphoscintigraphic demonstration of multiple drainage fields and/or multiple sentinel nodes (SNs). Patients who did not proceed to SNB were significantly older than those who did, more often had melanomas of the head or neck, and had more SNs and more nodal drainage fields. Of the 203 patients, 181 (89 %) were followed with high-resolution ultrasound of their SNs, which identified 33 % of the nodal recurrences before they were clinically apparent. Patients whose SNB was canceled had significantly worse recurrence-free survival and regional node disease-free survival, but melanoma-specific survival was similar. Compared to SN-positive patients, node-positive patients without SNB had significantly more involved nodes when a delayed lymphadenectomy was performed, but melanoma-specific survival was not significantly different after a median follow-up of 42 months.

Lymphoscintigraphy with ultrasound follow-up of previously identified SNs is an acceptable management strategy for patients in whom a SNB procedure is likely to be challenging.