Application of an indocyanine green surgical fluorescence imaging system in sentinel lymph node biopsy of acral malignant melanoma

Background: Regional lymph node status is an independent influencing factor for the prognosis of acral malignant melanoma, and the accuracy of sentinel lymph node biopsy (SLNB) is directly related to the judgment of regional lymph node status. This study aimed to explore the application value of indocyanine green (ICG) surgical fluorescence imaging system in the SLNB of acral malignant melanoma. Methods: A total of 34 patients with acral malignant melanoma were admitted to the Department of Burn and Plastic Surgery in Jiangsu Provincial People's Hospital from January 2020 to March 2020. Among these patients, 22 required SLNB. ICG and methylene blue (MB) were combined to intraoperatively trace the sentinel lymph nodes (SLNs). The total number of SLNs detected during the operation was counted. We compared the number, detection rate, as well as the detection rate and false negative rate of positive SLNs of SLNs detected by ICG, MB, and ICG combined with MB. Results: A total of 56 SLNs were detected in the 22 patients, among which 55 were detected by ICG (98%), 41 were detected by MB (71%), and 56 (100%) were detected by ICG combined with MB, and the average number of SLNs were 2.5, 1.64, and 2.55, respectively. A total of nine SLNs were detected, of which nine were detected by ICG (100%), seven by MB (78%), and nine by ICG combined with MB (100%). Patients with negative SLNs had no recurrence at the 6-month follow-up. Conclusions: Compared with MB, the ICG fluorescent imaging system can improve the detection rate of SLNs in patients with acral malignant melanoma. Also, ICG combined with MB was superior to ICG alone.