Effective Low-dose Escalation of Indocyanine Green for Near-infrared Fluorescent Sentinel Lymph Node Mapping in Melanoma

• Published in: Annals of surgical oncology 2013-07, Vol.20 (7), p.2357-2363
• Main Authors: Gilmore, Denis M., Khullar, Onkar V., Gioux, Sylvain, Stockdale, Alan, Frangioni, John V., Colson, Yolonda L., Russell, Sara E.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Coloring Agents - administration & dosage; Female; Fluorescence; Humans; Indocyanine Green - administration & dosage; Lymphatic Metastasis; Male; Medicine; Medicine & Public Health; Melanoma - diagnosis; Melanoma - diagnostic imaging; Melanoma - secondary; Melanomas; Middle Aged; Mitotic Index; Oncology; Radionuclide Imaging; Radiopharmaceuticals; Sentinel Lymph Node Biopsy - methods; Skin Neoplasms - pathology; Spectroscopy, Near-Infrared; Surgery; Surgical Oncology; Technetium Tc 99m Aggregated Albumin
• ISSN: 1068-9265; 1534-4681
• DOI: 10.1245/s10434-013-2905-x

Background Regional lymph node metastasis is the strongest prognostic factor in patients with melanoma. Published reports that used lymphoscintigraphy with radioactive colloids and blue dye demonstrated accurate sentinel lymph node (SLN) identification in inguinal nodes and axillary nodes, but decreased accuracy in cervical, popliteal, epitrochlear, and parascapular nodes. Near-infrared imaging (NIR) may utilize indocyanine green (ICG) to improve SLN identification. The safety, feasibility and optimal dose of albumin-bound ICG (ICG:HSA) was assessed by NIR to improve SLN mapping in patients with melanoma. Methods Twenty-five consecutive patients with biopsy-proven melanoma underwent standard SLN mapping with preoperatively administered technetium-99 m nanocolloid (Tc-99 m). Intraoperative NIR fluorescence imaging was performed after injection of 1.0 ml of 100, 250 or 500 μM of ICG:HSA in four quadrants around the primary lesion. Results NIR fluorescent imaging demonstrated accuracy of 98 % when compared with radioactive colloid. A total of 65 lymph nodes were identified (65 with Tc-99 m, 64 with ICG:HSA). Overall, successful mapping that used either technique was 96 % as one patient failed to map with either modality. As the dose of ICG was increased, the signal-to-background ratio increased from a median of 3.1 to 8.4 to 10.9 over the range of 100, 250, and 500 μM, respectively. Conclusions SLN mapping with ICG:HSA is feasible and accurate in melanoma. ICG has the added advantage of a low cost and an intraoperative technique that does not alter the surgical field, thus allowing for easy identification of SLNs.