Impact of indocyanine green‐guided extended pelvic lymph node dissection during robot‐assisted radical prostatectomy

Abstract

Objectives: To evaluate the effectiveness of indocyanine green-guided extended pelvic lymph node dissection during robot-assisted radical prostatectomy for intermediate-to high-risk prostate cancer. Materials and methods: After institutional review board approval, between July 2017 and December 2018, we carried out 100 indocyanine green-guided extended pelvic lymph node dissections in patients with localized intermediate-and high-risk prostate cancer, using the Firefly (Novadaq Technologies, Mississauga, ON, Canada) and da Vinci Xi surgical system (Intuitive Surgical, Sunnyvale, CA, USA). Indocyanine green was injected transrectally using ultrasound sonography before each surgery. Then, lymphatic drainage patterns and pathological findings were recorded. Results: Lymphatic drainage routes were successfully determined in 91 right-sided and 90 left-sided cases. Five main lymphatic pathways and sites were identified: (i) an internal route (57%); (ii) a lateral route (50%); (iii) a presacral route (20%); (iv) a paravesical artery site (20%); and (v) a pre-prostatic site (5%). Lymph node metastasis was positive in 15 patients, with 44 pathologically confirmed metastatic lymph nodes. Metastatic fluorescent lymph nodes were found in 15 out of 44 lymph nodes (34.1%). For sentinel lymph node identification, the 34% sensitivity and 64.8% specificity rates were detected in regard to identification of lymph node metastasis. Conclusions: Lymphatic drainage patterns from the prostate can be identified and classified using indocyanine green-guided extended pelvic lymph node dissections. Although the direct role of fluorescent lymph nodes in sentinel lymph node identification appears to be limited, the identification of lymphatic pathways could contribute to highquality extended pelvic lymph node dissection during robot-assisted radical prostatectomy.

The application of indocyanine green in guiding prostate cancer treatment

“…Metastatic fluorescent LNs (FLNs) were found in 15 out of 44 (34.1%) LNs. Although the direct role of FLNs in SLN identification appears to be limited, the identification of lymphatic pathways could contribute to high-quality ePLND during RARP [ 34 ]. In another study, ICG was injected into the prostate under transrectal ultrasound guidance just before surgery for 66 consecutive patients with clinically localized prostate cancer who underwent open radical prostatectomy.…”

“…Fluorescence targeted PLND showed superior sensitivity and negative predictive value compared to ePLND and super-ePLND to detect LN metastasis [ 32 ]. For SLN identification, in the study with the 100 ICG-guided ePLNDs, 34.0% sensitivity and 64.8% specificity rates were detected in regard to identification of LN metastasis [ 34 ].…”

“…While most studies found that it was useful [ 7 , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , 41 ], most of the studies also concluded that it could not replace ePLND because of its low sensitivity and complex drainage pattern [ 29 , 31 ]. In the retrospective study with twenty patients who received transperineal prostatic injections of ICG, across all patients, ICG had 62% sensitivity, 50% specificity, 8% positive predictive value, and 95% negative predictive value in detecting LN metastases.…”

Editorial Comment to Clear identification of the rare solitary external iliac lymph node metastasis of testicular cancer by using indocyanine green fluorescence guidance

“…ICG imaging may greatly aid lymph node dissection in patients with testicular cancer, as is the case for patients with other types of cancer 1 . ICG‐guided surgery has been reported for several types of cancer, including prostate cancer 2–4 . However, no report has dealt with testicular cancer.…”

“…1 ICG-guided surgery has been reported for several types of cancer, including prostate cancer. [2][3][4] However, no report has dealt with testicular cancer. This report is thus of interest and important.…”