Robot-assisted pelvic lymph node dissection using ICG testing in patients with prostate cancer

The objective is to investigate the possibility of using fluorescent testing in robot-assisted radical prostatectomy using indocyanine green (ICG testing) during pelvic lymph node dissection (PLND) in patients with localized prostate cancer. Materials and methods. Fifteen minutes prior to robot-assisted PLND, intraprostatic transperineal administration of 0.4 ml of indocyanine green (ICG) per lobe under transrectal ultrasound control was performed. Fluorescence map was used. After activation of the FireFly mode, fluorescence of the lymph nodes was evaluated. If a sentinel lymph node was present, lymph node dissection was performed using the FireFly mode. If fluorescence was diffuse, PLND using this option wasn't performed. Results. In total, 35 patients with localized prostate cancer underwent surgery. Mean age was 62.0 +/- 6.5 years (41-68 years), mean prostatespecific antigen level prior to surgery was 15.6 +/- 11.3 ng/ml (1.5-27.0 ng/ml). Postoperative examination revealed micrometastases in the lymph nodes in 7 (20 %) cases. Sentinel lymph nodes were detected in 29 patients. Intraoperative examination revealed sentinel lymph nodes metastases in 6 (17 %) cases, in other cases (83 %) metastases were absent. Morphological examination showed that in 5 (83 %) of 6 patients with lesions in the sentinel lymph node, micrometastases in other lymph nodes were present. In patients without lesions in the sentinel lymph node, no micrometastases in other lymph nodes were observed. PLND complications included lymphocele in 3 (8 %) patients, prolonged drain indwelling time in 5 (14 %) patients. Conclusion. Initial experience of our clinic shows reproducibility and low complications profile of fluorescence monitoring in the near-infrared region using ICG testing during robot-assisted PNLD. In conditions of continuous increase in the number of performed robot-assisted radical prostatectomies, ICG testing is a promising minimally invasive method for evaluation of regional metastases allowing to detect the sentinel lymph node. This approach allows to decrease the number of complications associated with PLND.