ICG-guided sentinel lymph node biopsy in melanoma is as effective as blue dye: A retrospective analysis

Introduction: Sentinel lymph node biopsy (SLNB) is a key procedure in the staging and management of melanoma. Traditionally, it is performed using a dual-mapping technique combining a radioactive isotope (RI) and blue dye (BD). Fluorescence-guided surgery with indocyanine green (ICG) has emerged as an alternative tracer, offering potential advantages in real-time visualization and operative efficiency. This study compares the efficacy of RI + ICG with RI + BD in SLNB for melanoma. Methods: We conducted a retrospective cohort study at a single center, including 311 patients who underwent SLNB for melanoma. Patients were divided into two groups: RI + BD (n = 227, January 2010–August 2022) and RI + ICG (n = 84, August 2022–February 2024). SLN detection rates, positive SLN rates, operative times, and postoperative complications were compared between the two groups. Results: Both groups were clinically and pathologically comparable. SLN detection rates were 100 % in the RI + BD group and 98.8 % in the RI + ICG group (p = 0.1). The median number of lymph nodes resected was lower in the RI + ICG group as compared to the RI + BD group (p = 0.047). While positive SLN rates were higher in the RI + ICG group (9.5 % vs. 6.2 %), this difference was not statistically significant (p = 0.3). ICG alone could not identify all the positive SLN. Postoperative complications, including seroma, did not differ significantly between groups. Conclusions: ICG-guided SLNB is comparable to BD-guided SLNB in terms of detection rate and SLN positivity, although it can not be used alone to identify all positive SLNBs. ICG-based fluorescence imaging is a promising technique that may enhance surgical efficiency in melanoma management.