Indocyanine Green Fluorescence Imaging with Lymphoscintigraphy Improves the Accuracy of Sentinel Lymph Node Biopsy in Melanoma

Background: Despite advances in melanoma management, there remains room for improvement in the accuracy of sentinel lymph node biopsy. The authors analyzed a prospective cohort of patients with primary cutaneous melanoma who underwent sentinel lymph node biopsy with lymphoscintigraphy and indocyanine green fluorescence to evaluate the quality and accuracy of this technique. Methods: Consecutive primary cutaneous melanoma patients who underwent sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green fluorescence from 2012 to 2018 were prospectively enrolled. Analysis was performed of melanoma characteristics, means of identifying sentinel lymph nodes, sentinel lymph node status, and recurrence. Results: Five hundred ninety-four melanomas and 1827 nodes were analyzed; 1556 nodes (85.2 percent) were identified by radioactivity/fluorescence, 255 (14 percent) by radioactivity only, and 16 (0.9 percent) with indocyanine green only. There were 163 positive sentinel nodes. One hundred forty-seven (90.2 percent) were identified by radioactivity/fluorescence, 13 (8 percent) by radioactivity only, and three (0.6 percent) with fluorescence only. Of the 128 patients with a positive biopsy, eight patients’ (6.3 percent) nodes were identified by radioactivity only and four (3.4 percent) with fluorescence only. There were 128 patients with a positive biopsy, 454 with a negative biopsy, and 12 patients who had a negative biopsy with subsequent nodal recurrence. Mean follow-up was 2.8 years. Conclusions: In the study of the largest cohort of patients with primary cutaneous melanoma who underwent a sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green–based technology, the quality and accuracy of this technique are demonstrated. This has important implications for melanoma patients, as the adoption of this approach with subsequent accurate staging, adjuvant workup, and treatment may improve survival outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.