Molecular Targeted Fluorescence-Guided Intraoperative Imaging of Bladder Cancer Nodal Drainage Using Indocyanine Green During Radical and Partial Cystectomy

A preliminary investigation of precise visualization, localization, and resection of pelvic lymph nodes in bladder cancer by using indocyanine green fluorescence-guided approach through intracutaneous dye injection into the lower limbs and perineum

Objective

This study aimed to investigate the feasibility and effectiveness of using indocyanine green (ICG) injected intracutaneously through the lower limbs and perineum for visualized tracking, localization, and qualitative assessment of pelvic lymph nodes (LNs) in bladder cancer to achieve their accurate resection.

Methods

First, ICG was injected into the LN metastasis model mice lower limbs, and real-time and dynamic in vivo and ex vivo imaging was conducted by using a near-infrared fluorescence imaging system. Additionally, 26 patients with bladder cancer were enrolled and divided into intracutaneous group and transurethral group. A near-infrared fluorescence imaging device with internal and external imaging probes was used to perform real-time tracking, localization, and resection of the pelvic LNs.

Results

The mice normal LNs and the metastatic LNs exhibited fluorescence. The metastatic LNs showed a significantly higher signal-to-background ratio than the normal LNs (3.9 ± 0.2 vs. 2.0 ± 0.1, p < 0.05). In the intracutaneous group, the accuracy rate of fluorescent-labeled LNs was 97.6%, with an average of 11.3 ± 2.4 LNs resected per patient. Six positive LNs were detected in three patients (18.8%). In the transurethral group, the accuracy rate of fluorescent-labeled LNs was 84.4%, with an average of 8.6 ± 2.3 LNs resected per patient. Two positive LNs were detected in one patient (12.5%).

Conclusion

Following the intracutaneous injection of ICG into the lower limbs and perineum, the dye accumulates in pelvic LNs through lymphatic reflux. By using near-infrared fluorescence laparoscopic fusion imaging, physicians can perform real-time tracking, localization, and precise resection of pelvic LNs.

Intravesical Contrast-Enhanced MRI: A Potential Tool for Bladder Cancer Surveillance and Staging

This review article gives an overview of the current state of the art of bladder cancer imaging and then discusses in depth the scientific and technical merit of a novel imaging approach, tracing its evolution from murine cancer models to cancer patients. While the poor resolution of soft tissue obtained by widely available imaging options such as abdominal sonography and radiation-based CT leaves them only suitable for measuring the gross tumor volume and bladder wall thickening, dynamic contrast-enhanced magnetic resolution imaging (DCE MRI) is demonstrably superior in resolving muscle invasion. However, major barriers still exist in its adoption. Instead of injection for DCE-MRI, intravesical contrast-enhanced MRI (ICE-MRI) instills Gadolinium chelate (Gadobutrol) together with trace amounts of superparamagnetic agents for measurement of tumor volume, depth, and aggressiveness. ICE-MRI leverages leaky tight junctions to accelerate passive paracellular diffusion of Gadobutrol (604.71 Daltons) by treading the paracellular ingress pathway of fluorescein sodium and of mitomycin (<400 Daltons) into bladder tumor. The soaring cost of diagnosis and care of bladder cancer could be mitigated by reducing the use of expensive operating room resources with a potential non-surgical imaging option for cancer surveillance, thereby reducing over-diagnosis and over-treatment and increasing organ preservation.

Application of Indocyanine Green in Combination with Da Vinci Xi Robot in Surgeries on the Upper Urinary Tract: A Case Series Study

BACKGROUND

To explore the application value of intraoperative imaging by indocyanine green (ICG) injection through the collection system of the urinary tract for Da Vinci Xi robot navigation in complex surgeries on the upper urinary tract.

METHODS

Data of 14 patients who underwent complex surgeries of the upper urinary tract post-ICG injection through the collection system of the urinary tract in combination with Da Vinci Xi robot navigation in the Tianjin First Central Hospital between December 2019 and October 2021 were analyzed in this retrospective study. The operation duration, estimated blood loss, and exposure time of ureteral stricture to ICG were evaluated. The renal functions and tumor relapse were evaluated after surgery.

RESULTS

Of the fourteen patients, three had distal ureteral stricture, five had ureteropelvic junction obstruction, four presented duplicate kidney and ureter, one had a giant ureter, and one presented an ipsilateral native ureteral tumor after renal transplantation. The surgeries in all patients were successful, with no conversion to open surgery. In addition, no injury to the surrounding organs, anastomotic stenosis or leakage, or ICG injection-related side effects were detected. Imaging at 3 months post-operatively revealed improved renal functions compared to those before the operation. No tumor recurrence or metastasis was observed in patient 14.

CONCLUSION

Fluorescence imaging compensating for the inadequacy of tactile feedback in the surgical operating system has advantages in identifying the ureter, determining the site of ureteral stricture, and protecting the blood flow for the ureter.

Opportunities of ICG-fluorescent imaging of lymph nodes during radical cystectomy in patients with bladder cancer: A review

Today, the "golden standard" for the treatment of aggressive forms of bladder cancer is radical cystectomy. An important stage is the pelvic lymphadenectomy. This procedure is crucial for staging the tumor process, determining the subsequent treatment tactics and improving the results of surgery. Currently, the concept of a signaling lymph node (LN) is actively developing, which allows reducing the necessary level of dissection of the pelvic LN. Reducing the number of resected LN increases the level of surgical safety of the patient. The leading method of intraoperative visualization of signal LN is the fluorescence of indocyanine green in the near infrared range of the spectrum. The prospects of this diagnostic method for radical cystectomy in patients with bladder cancer determine the vector of future scientific research in this area.

Methods of Sentinel Lymph Node Detection and Management in Urinary Bladder Cancer—A Narrative Review

Introduction: Detection of lymph node status in bladder cancer significantly impacts clinical decisions regarding its management. There is a wide range of detection modalities for this task, including lymphoscintigraphy, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, positron emission tomography, and fluoroscopy. We aimed to study the pre- and intraoperative detection modalities of sentinel lymph nodes in urinary bladder cancer. Method: This narrative review was performed by searching the PubMed and EMBASE libraries using the following search terms: (“Transitional cell carcinoma of the bladder” OR “urothelial cancer” OR “urinary bladder cancer” OR “bladder cancer”) AND ((“sentinel lymph node”) OR (“lymphatic mapping”) OR (“lymphoscintigraphy”) OR (“lymphangiography”) OR (“lymph node metastases”)). Studies analysing the effectiveness and outcomes of sentinel lymph node detection in bladder cancer were included, while non-English language, duplicates, and non-article studies were excluded. After analysing the libraries and a further manual search of bibliographies, 31 studies were included in this paper. We followed the RAMESES publication standard for narrative reviews to produce this paper. Results: Of the 31 studies included, 7 studies included multiple detection methods; 5 studies included lymphoscintigraphy; 5 studies included computed tomography and/or single-photon emission computed tomography; 5 studies included fluoroscopy; 4 studies included magnetic resonance imaging; and 5 studies included positron emission tomography. Discussion: Anatomical, radioactive, and functional detection modalities have been studied independently and in combination. The consensus is that preoperative detection with imaging helps guide surgical management and intraoperative detection methods help capture any lymph nodes that may have been missed. Each of these types of detection represent their own set of benefits and drawbacks, but there is currently limited evidence to support any change in overall practice to replace conventional staging.

Partial cystectomy for muscle-invasive bladder cancer: a review of the literature

The radical cystectomy (RC) for muscle-invasive bladder cancer is one of the most morbid and complex urologic procedures performed today. To avoid these complications, the partial cystectomy (PC) has been offered as an alternative in carefully selected patients as a means of achieving equal oncologic efficacy with less morbidity. Selection criteria should include solitary tumors without concomitant carcinoma in situ (CIS) and amenable to resection with 1–2 cm margins in a normally functioning bladder. In addition to the standard work-up, random bladder and prostatic biopsies may be performed. The PC can be performed through an open, laparoscopic, or robot-assisted approach, each with acceptable outcomes. A number of techniques have been developed to identify and resect the tumor completely with negative margins, while preventing tumor spillage within the abdomen. While there are no randomized trials, single institution series have demonstrated acceptable oncologic outcomes in appropriately selected patients. Therefore, offering PC in the appropriate candidate, including those patients who do not accept or are unfit for the associated morbidity of a RC, represents an acceptable alternative.

Indocyanine Green Fluorescence-Guided Partial Cystectomy and Pelvic Lymphadenectomy for Urachal Carcinoma

Background: Intraoperative indocyanine green near-infrared fluorescence guidance is an emerging optical imaging technology to facilitate better understanding of surgical landmarks. Herein, this technique was applied during the surgery for urachal carcinoma. Case Presentation: A 50-year-old man with urachal carcinoma underwent laparoscopic partial cystectomy and pelvic lymph node dissection (PLND). Before the laparoscopic surgery, indocyanine green was injected cystoscopically around the tumor at the submucosa level. The tumor location and lymph drainage were clearly viewed. The lymphatic flow was along the superior vesical artery and the umbilical ligament. The obturator and external lymph nodes were not fluoresced. Template PLND was performed. Partial cystectomy was completed with cystoscopic monitoring of the margin and with endoscopic stapler to avoid tumor spillage. Conclusion: Intraoperative indocyanine green fluorescence views lymph drainage and tumor location and is useful to improve the quality of PLND and partial cystectomy.

The evolving role of lymphadenectomy for bladder cancer: why, when, and how

Radical cystectomy (RC) represents a standard treatment for non-metastatic muscle-invasive and select high-risk non-muscle invasive bladder cancer. Lymphadenectomy performed at time of RC identifies nodal metastases in up to 25% of patients despite normal imaging. There has been an increasing utilization of pelvic lymph node dissection (PLND) with RC since 1950, and in fact lymph node dissection is now recommended in contemporary National Comprehensive Cancer Network (NCCN) guidelines. Benefits of removing of nodal disease include improved staging, guidance for adjuvant treatment, and potentially improved oncologic outcomes. Advantages of dissection have been suggested among both node-negative and node-positive patients. Numerous studies have attempted to define the optimal dissection characteristics of lymphadenectomy with regard to nodal yield and anatomic boundaries of dissection. The ideal extent of lymphadenectomy remains uncertain due to the retrospective and non-randomized nature of the majority of existing reports, which are thereby limited by significant confounding and selection bias. Two randomized controlled trials have investigated this issue, one of which LEA AUO AB 25/02 recently reported its outcomes, demonstrating no significant improvement in 5-year outcomes with an extended dissection. Meanwhile, the Southwest Oncology Group 1011 trial has completed enrollment and data are maturing. While current data preclude definitive recommendations, herein we review the why, when, and how to perform a PLND for bladder cancer.

Fewer tumour draining sentinel nodes in patients with progressing muscle invasive bladder cancer, after neoadjuvant chemotherapy and radical cystectomy

Purpose

To examine the relationship between the number of tumour draining sentinel nodes (SNs) and pathoanatomical outcomes, in muscle-invasive bladder cancer (MIBC), in patients undergoing neoadjuvant chemotherapy (NAC) and radical cystectomy (RC).

Materials and Methods

In an ongoing prospective multicenter study, we included 230 patients with suspected urothelial MIBC from ten Swedish urological centers. All underwent TURb and clinical staging. From the cohort, 116 patients with urothelial MIBC; cT2-cT4aN0M0, underwent radical cystectomy (RC) and lymphadenectomy with SN-detection (SNd). 83 patients received cisplatin-based NAC and 33 were NAC-naïve. The number and locations of detected SNs and non-SNs were recorded for each patient. The NAC treated patients were categorized by pathoanatomical outcomes post-RC into three groups: complete responders (CR), stable disease (SD) and progressive disease (PD). Selected covariates with possible impact on SN-yield were tested in uni -and multivariate analyses for NAC-treated patients only.

Results

In NAC treated patients, the mean number of SNs was significantly higher in CR patients (3.3) and SD patients (3.6) compared with PD patients (1.4) (p = 0.034). In a linear multivariate regression model, the number of harvested nodes was the only independent variable that affected the number of SNs (p = 0.0004).

Conclusions

The number of tumor-draining SNs in NAC-treated patients was significantly lower in patients with progressive disease.