Fluorescence Guided Targeted Pelvic Lymph Node Dissection for Intermediate and High Risk Prostate Cancer

Abstract

Fluorescence targeted pelvic lymph node dissection allows for the lymphatic drainage of the prostate to be identified with great reliability. Since only the nodes draining the prostate are removed, the absolute number of removed nodes is decreased while diagnostic accuracy is increased.

Lymphatic targeting drug delivery system and tumor treatment

“…The process of metastasis and proliferation of malignant cells is the process of transferring cells to lymph nodes. Therefore, if the lymphatic targeting drug delivery can be conducted, the drugs will directly act on the metastasis, so that the control rate of malignant tumors can be increased [12][13][14][15] . Lymph is lipophilic, and treating the patients with malignant tumors with liposome or niosome drugs is the main idea of the current lymphatic targeting drug delivery.…”

Current perspectives of sentinel lymph node dissection at the time of radical surgery for prostate cancer

“…At high concentration, the ICG fluorophore is dark green and generates similar lymphovascular staining patterns as blue dye, which enables visual detection of superficial lymph vessels and nodes [22,25]. In pelvic SLND, ICG is diluted to a pale green solution at concentrations between 0.05mg/ml and 2.5mg/ml prior to prostatic injection [6,7,23,[26][27][28][29][30] and activated to emit near-infrared fluorescence (NIRF) by an excitation light, itself in the near-infrared (NIR) spectrum. In a prospective study comparing ICG to 99m Tc in melanoma patients, Stoffels et al demonstrated a tissue penetrance of only 10-15mm with free-ICG, preventing detection of lymphatic pathways extending to deep tissues [22].…”

“…Importantly, they also demonstrated that half of the patients had SLN detected exclusively by fluorescence, two patients had nodes detected by 99m Tc only while the remaining 11 patients had nodes detected by both modalities. They later dispensed with 99m Tc-colloid in a study with a larger proportion of high-risk PCa patients and reported 97.7% sensitivity of free ICG-guided PLND with only 1 case of procedural failure giving complete non-visualisation in a node-positive patient [26]. However, the rapid distribution of the small ICG molecules in the lymphatic system (5-30 minutes [23,26,28,30,31]) combined to low tissue penetrance strictly restricted ICG use to the intraoperative phase, through prostatic injection under direct vision or immediately preceding laparotomy/laparoscopy.…”

Fluorescent Image–Guided Surgery with an Anti-Prostate Stem Cell Antigen (PSCA) Diabody Enables Targeted Resection of Mouse Prostate Cancer Xenografts in Real Time

“…The posterolateral prostate and prostatic apex remain the most common sites for positive surgical margins (8), which are intimately associated with the neurovascular bundle controlling erectile function and urinary sphincter, respectively. As urinary incontinence and sexual dysfunction remain major issues postoperatively (9), surgeon reluctance to remove healthy tissue in an attempt to reduce these side effects likely account for these higher rates. The ability to visualize small foci of extracapsular extension of prostate cancer at the time of surgery may reduce the incidence of positive surgical margins while reducing damage to critical adjacent structures.…”

“…Intraprostatic free Indocyanin Green (ICG) has been utilized clinically in prostatectomy as a lymphangiographic agent in the detection of sentinel lymph nodes and for delineation of prostate by limited diffusion (9, 10). However, use of free ICG is limited by the lack of biochemical specificity to prostate or prostate cancer, and suffers from dye spillage from handling or manipulating fluorescent tissue.…”