Efficacy of indocyanine green fluorescence‐guided inguinal lymph node dissection for penile cancer: a randomised trial

OBJECTIVES: To investigate the safety and efficacy of indocyanine green (ICG) fluorescence-guided inguinal lymph node dissection (ILND) in patients with penile cancer. PATIENTS AND METHODS: A prospective, single-blind, randomised controlled clinical trial (ChiCTR2100044584) was performed among patients with penile caner who underwent bilateral modified ILND at four centres in China between 1 April 2021 and 30 June 2022. Patients aged 18-80 years and diagnosed with squamous cell carcinomas were included. Each enrolled patient was randomly assigned to either ICG fluorescence-guided ILND by a laparoscopic or robot-assisted approach in one groin, with non-ICG fluorescence-guided ILND in the other groin acting as a control. The primary outcome was the number of retrieved ILNs. Secondary outcomes included complications according to the Clavien-Dindo classification and the ILN non-compliance (inadequate removal of ILNs) rate. RESULTS: A total of 45 patients were included in the intention-to-treat (ITT) analysis, and the 42 who completed the entire study were included in the per protocol (PP) analysis. There were no ICG-related complications in any of the patients. The results of the ITT and PP analyses indicated that the total number of unilateral ILNs retrieved was higher on the ICG side than on the non-ICG side (mean 13 vs 9 ILNs, difference 4 ILNs [95% CI 2.7-4.4], P = 0.007), and the number of unilateral deep and superficial ILNs was higher on the ICG side. Furthermore, the LN non-compliance rate was lower on the ICG side than on the non-ICG side. Additionally, there was no significant difference in local complications in the groins between the two sides (P > 0.05). CONCLUSION: An ICG fluorescence-guided ILND was safe for patients with penile cancer. This procedure can improve the number of ILNs retrieved and reduce the LN non-compliance rate without increased complications. ICG fluorescence-guided ILND is beneficial and recommended for selected patients with penile cancer.