Near-Infrared Sentinel Lymph Node Mapping With Indocyanine Green Using the VITOM II ICG Exoscope for Open Surgery for Gynecologic Malignancies

Preliminary Experience with 3-Dimensional Exoscope-Assisted Laryngoplasty

OBJECTIVE

Laryngoplasty requires the manipulation of the vocal folds, which are not visible during the operation. The widespread use of this technique is limited by the need for adequate knowledge of anatomy, the small surgical field, and the high level of skill required for the procedure. An exoscope has been developed to provide a stereoscopic view similar to that of a microscope while using the same compact endoscopic tool. This study aimed to determine whether the three-dimensional (3D) exoscopic surgical technique could be applied to laryngoplasty and explore its possibility to ultimately replace the current approach.

METHODS

This was a retrospective case series analysis, which included 28 patients with hoarseness who underwent surgery with (Exoscope; n = 12) or without (Macrosurgery; n = 16) a 3D exoscope between July 2018 and February 2021. The feasibility of performing all surgical steps with the 3D exoscope was evaluated. The Exoscope and Macrosurgery groups were compared for surgical time, vocal function outcomes, and complications. Questionnaires were completed by medical staff regarding the usefulness of medical education.

RESULTS

No intraoperative or postoperative complications occurred in either procedure. The operative time was similar in both groups. The vocal function outcomes were also comparable between the groups. Questionnaires revealed that the exoscope was useful in terms of sharing information on surgical procedures and anatomy, as well as functioning as an educational tool.

CONCLUSION

While this was a preliminary study, our results indicated that the exclusive use of the 3D exoscope was feasible for open approaches.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1813-1819, 2024.

Binocular microscopes versus exoscopes: Experiences and performance in simulated otologic surgery

Objectives

Exoscopes represent a promising alternative to conventional binocular microscopes (OM) in otology offering potential advantages such as enhanced ergonomics and a more compact device design. While previous research has demonstrated the effectiveness of exoscopes in various surgical specialties, their objective assessment in the field of otology remains limited. Therefore, this investigation aims to assess task-based efficiency associated with exoscopes in the field of otology by use of simulated surgical models.

Methods

A prospective cross-over study design was used to compare an OM to an exoscope in otolaryngology residents and medical students. Participants performed five tasks on 3D-printed ear models using both the exoscope and OM. Data collection included completion time, frequency of predefined errors, mental effort, and user experience. Subgroup analysis was performed based on level of experience.

Results

Fourteen students and fifteen residents participated. Participants completed four of five tasks faster with the OM and there was no difference in number of errors committed. When separated by surgical experience, residents performed four of five tasks faster using the OM while students completed one of five tasks faster with the OM. Students committed more errors with the exoscope for one task with no difference in errors for residents. There was no difference in perceived difficulty performing tasks with either visualization system. Exit survey results showed more favorable opinions of the OM among residents and more favorable opinions of the exoscope among students.

Conclusions

The exoscope permits successful performance in simulated otologic tasks. Task performance and user experience between operative microscopes and exoscopes differ based on level of surgical experience.

Level of Evidence

2.

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.

Is the exoscope ready to replace the operative microscope in transoral surgery?

PURPOSE OF REVIEW

Exoscopes are external digital devices that provide enhanced and magnified visualization of the surgical field. They usually have dedicated digital controls and a more compact mechanical structure than operative microscopes and current robotic surgical systems. This technology has significant potential in otolaryngology - head and neck surgery, especially concerning the field of transoral approaches. We herein analysed the overall technical characteristics of currently available exoscopic systems and contextualized their advantages and drawbacks in the setting of transoral surgery.

RECENT FINDINGS

The actual advantages of exoscopy are still indeterminate, as it has only been applied to limited surgical series. However, its specific properties are herein compared with conventional transoral microsurgery and transoral robotic surgery, discussing the available literature on such a topic, filtered on the basis of the authors' experience and its possible future evolutions. Finally, a summary of current experiences in the field of three-dimensional (3D) transoral exoscopic surgery is presented, highlighting differences compared with standard approaches.

SUMMARY

3D-exoscopic transoral surgery will possibly play an essential role in future management of early laryngeal and oropharyngeal lesions, significantly shifting the paradigms of this type of procedures.

Sentinel Lymph Node Staging with Indocyanine Green for Patients with Cervical Cancer: The Safety and Feasibility of Open Approach Using SPY-PHI Technique

Simple Summary

While several studies have been conducted on the safety and efficacy of sentinel lymph node technique during minimally invasive radical hysterectomy and indicated that using indocyanine green alone is a better tracer agent, there is now high unmet medical need and growing demand for more data about sentinel lymph node detection and the most suitable tracer in open surgery for cervical cancer, especially after the publishing of the of Laparoscopic Approach to Cervical Cancer (LACC) Trial data. The aim of this study is to assess the feasibility and safety of sentinel lymph nodes with indocyanine green in cervical cancer patients undergoing radical hysterectomy in open surgery and to compare the detection rates of this tracer in the open versus laparoscopic approaches.

Abstract

(1) Background: Sentinel lymph node staging (SLN) with indocyanine green (ICG) in cervical cancer is the standard of care in most national and international guidelines. However, the vast majority of relevant studies about the safety and feasibility of this method are conducted on minimally invasive surgery; (2) Methods: This study is a retrospective analysis of a retrospective collected database of 76 consecutive patients with cervical cancers, who were operated laparoscopically (50%), or laparotomy (50%). Sentinel nodes were defined as the ICG-positive pelvic nodes in the first and second echelons. False negative cases were defined as positive non-sentinel lymph nodes despite successful sentinel mapping or failed mapping bilaterally by per-patient assessment or unilaterally by pelvic sidewall assessment; (3) Results: Regardless of the approach (open or laparoscopic), the SLN technique achieved a total sensitivity, specificity, and negative predictive value (NPV) of 94.7%, 98.6%, and 94.7%, respectively in the entire sample. The bilateral detection rate was as high as 93.4% with identical results in both approaches. The sensitivity and NPV for SNL in open surgery was found to be similar to minimal access surgery; (4) Conclusions: ICG and SPY-PHI technique is a reliable tool to detect sentinel lymph nodes in cervical cancer during laparotomy.

Sentinel node biopsy for diagnosis of lymph node involvement in endometrial cancer

BACKGROUND

Pelvic lymphadenectomy provides prognostic information for those diagnosed with endometrial (womb) cancer and provides information that may influence decisions regarding adjuvant treatment. However, studies have not shown a therapeutic benefit, and lymphadenectomy causes significant morbidity. The technique of sentinel lymph node biopsy (SLNB), allows the first draining node from a cancer to be identified and examined histologically for involvement with cancer cells. SLNB is commonly used in other cancers, including breast and vulval cancer. Different tracers, including colloid labelled with radioactive technetium-99, blue dyes, e.g. patent or methylene blue, and near infra-red fluorescent dyes, e.g. indocyanine green (ICG), have been used singly or in combination for detection of sentinel lymph nodes (SLN).

OBJECTIVES

To assess the diagnostic accuracy of sentinel lymph node biopsy (SLNB) in the identification of pelvic lymph node involvement in women with endometrial cancer, presumed to be at an early stage prior to surgery, including consideration of the detection rate.

SEARCH METHODS

We searched MEDLINE (1946 to July 2019), Embase (1974 to July 2019) and the relevant Cochrane trial registers.

SELECTION CRITERIA

We included studies that evaluated the diagnostic accuracy of tracers for SLN assessment (involving the identification of a SLN plus histological examination) against a reference standard of histological examination of removed pelvic +/- para-aortic lymph nodes following systematic pelvic +/- para-aortic lymphadenectomy (PLND/PPALND) in women with endometrial cancer, where there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two review authors (a combination of HN, JM, NW, RG, and WH) independently screened titles and abstracts for relevance, classified studies for inclusion/exclusion and extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We calculated the detection rate as the arithmetic mean of the total number of SLNs detected out of the total number of women included in the included studies with the woman as the unit of analysis, used univariate meta-analytical methods to estimate pooled sensitivity estimates, and summarised the results using GRADE.

MAIN RESULTS

The search revealed 6259 unique records after removal of duplicates. After screening 232 studies in full text, we found 73 potentially includable records (for 52 studies), although we were only able to extract 2x2 table data for 33 studies, including 2237 women (46 records) for inclusion in the review, despite writing to trial authors for additional information. We found 11 studies that analysed results for blue dye alone, four studies for technetium-99m alone, 12 studies that used a combination of blue dye and technetium-99m, nine studies that used indocyanine green (ICG) and near infra-red immunofluorescence, and one study that used a combination of ICG and technetium-99m. Overall, the methodological reporting in most of the studies was poor, which resulted in a very large proportion of 'unclear risk of bias' ratings. Overall, the mean SLN detection rate was 86.9% (95% CI 82.9% to 90.8%; 2237 women; 33 studies; moderate-certainty evidence). In studies that reported bilateral detection the mean rate was 65.4% (95% CI 57.8% to 73.0%) . When considered according to which tracer was used, the SLN detection rate ranged from 77.8% (95% CI 70.0% to 85.6%) for blue dye alone (559 women; 11 studies; low-certainty evidence) to 100% for ICG and technetium-99m (32 women; 1 study; very low-certainty evidence). The rates of positive lymph nodes ranged from 5.2% to 34.4% with a mean of 20.1% (95% CI 17.7% to 22.3%). The pooled sensitivity of SLNB was 91.8% (95% CI 86.5% to 95.1%; total 2237 women, of whom 409 had SLN involvement; moderate-certainty evidence). The sensitivity for of SLNB for the different tracers were: blue dye alone 95.2% (95% CI 77.2% to 99.2%; 559 women; 11 studies; low-certainty evidence); Technetium-99m alone 90.5% (95% CI 67.7% to 97.7%; 257 women; 4 studies; low-certainty evidence); technetium-99m and blue dye 91.9% (95% CI 74.4% to 97.8%; 548 women; 12 studies; low-certainty evidence); ICG alone 92.5% (95% CI 81.8% to 97.1%; 953 women; 9 studies; moderate-certainty evidence); ICG and blue dye 90.5% (95% CI 63.2.6% to 98.1%; 215 women; 2 studies; low-certainty evidence); and ICG and technetium-99m 100% (95% CI 63% to 100%; 32 women; 1 study; very low-certainty evidence). Meta-regression analyses found that the sensitivities did not differ between the different tracers used, between studies with a majority of women with FIGO stage 1A versus 1B or above; between studies assessing the pelvic lymph node basin alone versus the pelvic and para-aortic lymph node basin; or between studies that used subserosal alone versus subserosal and cervical injection. It should be noted that a false-positive result cannot occur, as the histological examination of the SLN is unchanged by the results from any additional nodes removed at systematic lymphadenectomy.

AUTHORS' CONCLUSIONS

The diagnostic test accuracy for SLNB using either ICG alone or a combination of a dye (blue or ICG) and technetium-99m is probably good, with high sensitivity, where a SLN could be detected. Detection rates with ICG or a combination of dye (ICG or blue) and technetium-99m may be higher. The value of a SLNB approach in a treatment pathway, over adjuvant treatment decisions based on uterine factors and molecular profiling, requires examination in a high-quality intervention study.

Exploratory Study of the Clinical Value of Near-Infrared Sentinel Lymph Node Mapping With Indocyanine Green in Vulvar Cancer Patients

Background

This study aimed to evaluate the clinical value of indocyanine green sentinel lymph node (SLN) mapping in patients with vulvar cancer. The conventional procedure of SLN mapping in vulvar cancer includes peritumoral injection of technetium-99m nanocolloid before surgery and intraoperative injection of a blue dye. However, these techniques harbor some limitations. Near-infrared fluorescence imaging with indocyanine green has gained popularity in SLN mapping in different types of cancer.

Methods

We analyzed retrospectively vulvar cancer patients at our institution between 2013 and 2020 undergoing indocyanine green SLN mapping by applying video telescope operating microscope system technology.

Results

64 groins of 34 patients were analyzed. In 53 groins we used technetium-99m nanocolloid, in four patent blue, and in five both techniques, additionally to indocyanine green for SLN detection. In total, 120 SLNs were identified and removed. The SLN detection rate of indocyanine green was comparable to technetium-99m nanocolloid (p=.143) and higher than patent blue (p=.003). The best results were achieved using a combination of ICG and technetium-99m nanocolloid (detection rate of 96.9%). SLN detection rates of indocyanine green were significantly higher in patients with positive lymph nodes (p=.035) and lymphatic space invasion (p=.004) compared to technetium-99m nanocolloid.

Conclusion

Indocyanine green SLN mapping in vulvar cancer is feasible and safe, with reasonable detection rates. Due to its easy application and few side effects, it offers a sound alternative to the conventional SLN mapping techniques in vulvar cancer. In patients with lymph node metastasis, indocyanine green even outperformed technetium-99m nanocolloid in terms of detection rate.

Sentinel lymph node mapping with indocyanine green in cervical cancer patients undergoing open radical hysterectomy: a single-institution series

PURPOSE

To assess the rate of bilateral sentinel lymph node (SLN) detection with indocyanine green (ICG), to evaluate the sensitivity and the negative predictive value of cervical cancer patients undergoing open radical hysterectomy; to compare open versus minimally invasive SLN biopsy performance and to assess factors related to no/unilateral SLN mapping.

METHODS

We retrospectively reviewed consecutive patients with FIGO 2018 stage IA1 with lymph-vascular space involvement to IIB and IIIC1p cervical carcinoma who underwent SLN mapping with ICG followed by systematic pelvic lymphadenectomy between 05/2017 and 06/2020. Patients were divided according to surgical approach for statistical analysis.

RESULTS

Eighty-five patients met inclusion criteria. Twenty-seven (31.8%) underwent open and 58 (68.2%) underwent minimally invasive SLN mapping. No difference in any SLN mapping (laparotomy 92.6% and minimally invasive 91.4%) or in SLN bilateral detection (laparotomy 72.0% and minimally invasive 84.9%) (p = 0.850 and p = 0.222, respectively), in median number of SLNs mapped and retrieved (2 in both groups, p = 0.165) and in site of SLN mapping per hemi-pelvis (right side, p = 0273 and left side, p = 0.618) was evident between open and minimally invasive approach. Per-patient sensitivity of SLN biopsy in laparotomy was 83.3% (95% CI 35.9-99.6%) and the negative predictive value was 95.0% (95% CI 76.0-99.1%). No difference in per-patient sensitivity was noted between two approaches (p = 0.300). None of the analyzed variables was associated with no/unilateral SLN mapping.

CONCLUSION

The use of ICG to detect SLN in cervical cancer treated with open surgery allows a bilateral detection, sensitivity and negative predictive value comparable to minimally invasive surgery with potential advantages of ICG compared to other tracers.

VITOM 4K 3D Exoscope: A Preliminary Experience in Thyroid Surgery

Since its introduction in 2008, the Karl Storz 4K 3D VITOM® exoscope (Karl Storz SE & Co. KG, Tuttlingen, Germany) has been successfully used in various surgical disciplines. This paper describes our department’s experience using this technology and its use in the first total thyroidectomy case. The set up of the 3D VITOM exoscope in the operating theatre allows for a user-friendly approach to thyroid surgery with the exoscope placed out of the line of sight of the surgeon with a monitor placed directly ahead. The surgeon has a control panel within reach, which allows for adjustments to image magnification and focus. The use of the 3D VITOM exoscope has the potential to confer significant improvements in patient outcomes by promoting efficient and safer surgery through superior operative visualisation.

Utility of Intraoperative Fluorescence Imaging in Gynecologic Surgery: Systematic Review and Consensus Statement

BACKGROUND

This study aimed to review the current knowledge on the utility of intraoperative fluorescence imaging in gynecologic surgery and to give evidence-based recommendations to improve the quality of care for women who undergo gynecologic surgery.

METHODS

A computer-based systematic review of the MEDLINE, CENTRAL, Pubmed, EMBASE, and SciSearch databases as well as institutional guidelines was performed. The time limit was set at 2000-2019. For the literature search, PRISMA guidelines were followed. A modified-Delphi method was performed in three rounds by a panel of experts to reach a consensus of conclusions and recommendations.

RESULTS

Indocyanine green (ICG) is used primarily in gynecology for sentinel node-mapping. In endometrial and cervical cancer, ICG is a feasible, safe, time-efficient, and reliable method for lymphatic mapping, with better bilateral detection rates. Experience in vulvar cancer is more limited, with ICG used together with Tc-99 m as a dual tracer and alone in video endoscopic inguinal lymphadenectomy. In early ovarian cancer, results are still preliminary but promising. Indocyanine green fluorescence imaging also is used for ureteral assessment, allowing intraoperative ureteral visualization, to reduce the risk of ureteral injury during gynecologic surgery.

CONCLUSIONS

For most gynecologic cancers, ICG fluorescence imaging is considered the tracer of choice for lymphatic mapping. The use of this new technology expands to a better ureteral assessment.

Near-infrared fluorescence imaging compared to standard sentinel lymph node detection with blue dye in patients with vulvar cancer - a randomized controlled trial

OBJECTIVE

The aim of this study was to assess the superiority of ICG-^99mTc-nanocolloid for the intraoperative visual detection of sentinel lymph nodes (SLNs) in vulvar squamous cell carcinoma (VSCC) patients compared to standard SLN detection using ^99mTc-nanocolloid with blue dye.

METHODS

In this multicenter, randomized controlled trial, VSCC patients underwent either the standard SLN procedure or with the hybrid tracer ICG-^99mTc-nanocolloid. The primary endpoint was the percentage of fluorescent SLNs compared to blue SLNs. Secondary endpoints were successful SLN procedures, surgical outcomes and postoperative complications.

RESULTS

Forty-eight patients were randomized to the standard (n = 24) or fluorescence imaging group (n = 24) using ICG-^99mTc-nanocolloid. The percentage of blue SLNs was 65.3% compared to 92.5% fluorescent SLNs (p < 0.001). A successful SLN procedure was obtained in 92.1% of the groins in the standard group and 97.2% of the groins in the fluorescence imaging group (p = 0.33). Groups did not differ in surgical outcome, although more short-term postoperative complications were documented in the standard group (p = 0.041).

CONCLUSIONS

Intraoperative visual detection of SLNs in patients with VSCC using ICG-^99mTc-nanocolloid was superior compared to ^99mTc-nanocolloid and blue dye. The rate of successful SLN procedures between both groups was not significantly different. Fluorescence imaging has potential to be used routinely in the SLN procedure in VSCC patients to facilitate the search by direct visualization.

CLINICAL TRIAL REGISTRATION

Netherlands Trial Register (Trial ID NL7443).

Feasibility of hand-assisted laparoscopic sentinel node biopsy in open endometrial cancer surgery

Background: The aim of this preliminary retrospective study was to assess the feasibility and accuracy of Indocyanine Green (ICG) sentinel node (SLN) sampling using a laparoscopic camera during open endometrial cancer surgery.Material and methods: Retrospective study. Fourteen women with endometrial cancer, not fit for a complete laparoscopic staging, underwent SLN mapping using the IMAGE1 camera during open surgery.Results: The median age of patients was 67 (range 33-86) years. Median BMI was 31 (range 23-58). Mean operative time 157.5 minutes and hospital stay three days. The overall detection rate of SLN mapping was 93%. Bilateral detection was 86%. No post-operative short or long-term complications were observed.Conclusions: Real-time NIR technology supported by the IMAGE1 S is a reliable system and represents a promising method for SLN mapping in selected cases with EC and severe surgical risks, during 48 traditional open approaches. The use of laparoscopy ICG in open surgery seems to be a feasible and useful tool for the detection of SLN in endometrial cancer patients with intraoperative and/or postoperative high morbidity risk. It represents a valid alternative to robotic surgery, particularly in countries and centers where the robotic platform or SPY system for open surgery are not available.

Usefulness of colonic tattooing using indocyanine green in patients with colorectal tumors

AIM

To prove that tattooing using indocyanine green (ICG) is feasible in laparoscopic surgery for a colon tumor.

METHODS

From January 2012 to December 2016, all patients who underwent laparoscopic colonic surgery were retrospectively screened, and 1010 patients with colorectal neoplasms were included. Their lesions were tattooed with ICG the day before the operation. The tattooed group (TG) included 114 patients, and the non-tattooed group (NTG) was selected by propensity score matching of subjects based on age, sex, tumor staging, and operation method (n = 228). In total, 342 patients were enrolled. Between the groups, the changes in [Delta (Δ), preoperative-postoperative] the hemoglobin and albumin levels, operation time, hospital stay, oral ingestion period, transfusion, and perioperative complications were compared.

RESULTS

Preoperative TG had a shorter operation time (174.76 ± 51.6 min vs 192.63 ± 59.9 min, P < 0.01), hospital stay (9.55 ± 3.36 d vs 11.42 ± 8.23 d, P < 0.01), and post-operative oral ingestion period (1.58 ± 0.96 d vs 2.81 ± 1.90 d, P < 0.01). The Δ hemoglobin (0.78 ± 0.76 g/dL vs 2.2 ± 1.18 g/dL, P < 0.01) and Δ albumin (0.41 ± 0.44 g/dL vs 1.08 ± 0.39 g/dL, P < 0.01) levels were lower in the TG. On comparison of patients in the “N0” and “N1 or N2” groups, the N0 colon cancer group had a better operation time, length of hospital stay, oral ingestion period, Δ hemoglobin, and Δ albumin results than those of the N1 or N2 group. The operation methods affected the results, and laparoscopic anterior resection (LAR) showed similar results. However, for left and right hemicolectomy, both groups showed no difference in operation time or hospital stay.

CONCLUSION

Preoperative tattooing with ICG is useful for laparoscopic colectomy, especially in the N0 colon cancer group and LAR.

A practical guide for the use of indocyanine green and methylene blue in fluorescence-guided abdominal surgery

Near-infrared (NIR) fluorescence imaging is gaining clinical acceptance over the last years and has been used for detection of lymph nodes, several tumor types, vital structures and tissue perfusion. This review focuses on NIR fluorescence imaging with indocyanine green and methylene blue for different clinical applications in abdominal surgery with an emphasis on oncology, based on a systematic literature search. Furthermore, practical information on doses, injection times, and intraoperative use are provided.

Utility of Laparoscopic Indocyanine Green-Guided Sentinel Node Biopsy in Open Cervical Cancer Surgery

OBJECTIVE

Multiple tracers have been used to improve lymphatic mapping and to reduce the false-negative rate of the sentinel node detection in gynecologic cancers. Nowadays, 99mTc colloids combined with blue-dye technique is the most extended technique. New alternatives such as the fluorescent indocyanine green and near-infrared fluorescent imaging detection have been introduced in lymphatic mapping staging procedures because of its easier visualization compared with the previous tracers.

METHODS

We used the laparoscopic infrared camera for the indocyanine green-guided sentinel node biopsy in a laparotomic radical hysterectomy in a pregnant patient after a cesarean section, with the aim of improving the detection rate of sentinel node biopsy in open surgery.

RESULTS

The technique was used in the first patient with accurate detection of sentinel node and no complications during the procedure.

CONCLUSIONS

The use of laparoscopic indocyanine green in open surgery may be a useful tool for the detection of sentinel node biopsy.

Sentinel Lymph Nodes Mapping in Cervical Cancer a Comprehensive Review

Objective

A comprehensive literature search for more recent studies pertaining to sentinel lymph node mapping in the surveillance of cervical cancer to assess if sentinel lymph node mapping has sensitivity and specificity for evaluation of the disease; assessment of posttreatment response and disease recurrence in cervical cancer.

Materials and Methods

The literature review has been constructed on a step wise study design that includes 5 major steps. This includes search for relevant publications in various available databases, application of inclusion and exclusion criteria for the selection of relevant publications, assessment of quality of the studies included, extraction of the relevant data and coherent synthesis of the data.

Results

The search yielded numerous studies pertaining to sentinel lymph node mapping, especially on the recent trends, comparison between various modalities and evaluation of the technique. Evaluation studies have appraised high sensitivity, high negative predictive values and low false-negative rate for metastasis detection using sentinel lymph node mapping. Comparative studies have established that of all the modalities for sentinel lymph node mapping, indocyanine green sentinel lymph node mapping has higher overall and bilateral detection rates. Corroboration of the deductions of these studies further establishes that the sentinel node detection rate and sensitivity are strongly correlated to the method or technique of mapping and the history of preoperative neoadjuvant chemotherapy.

Conclusions

The review takes us to the strong conclusion that sentinel lymph node mapping is an ideal technique for detection of sentinel lymph nodes in cervical cancer patients with excellent detection rates and high sensitivity. The review also takes us to the supposition that a routine clinical evaluation of sentinel lymph nodes is feasible and a real-time florescence mapping with indocyanine green dye gives better statistically significant overall and bilateral detection than methylene blue.

Navigation of Fluorescence Cameras during Soft Tissue Surgery-Is it Possible to Use a Single Navigation Setup for Various Open and Laparoscopic Urological Surgery Applications?

PURPOSE

Real-time visualization fluorescence imaging can guide surgeons during tissue resection. Unfortunately tissue induced signal attenuation limits the value of this technique to superficial applications. By positioning the fluorescence camera via a dedicated navigation setup we reasoned that the technology could be made compatible with deeper lesions, increasing its impact on clinical care. Such an impact would benefit from the ability to implement the navigation technology in different surgical settings. For that reason we evaluated whether a single fluorescence camera could be navigated toward targeted lesions during open and laparoscopic surgery.

MATERIALS AND METHODS

A fluorescence camera with scopes available for open and laparoscopic procedures was integrated with a navigation platform. Lymph nodes identified on SPECT/CT (single photon emission computerized tomography/computerized tomography) or free-hand single photon emission computerized tomography acted as navigation targets and were displayed as augmented overlays in the fluorescence camera video feed. The accuracy of this setup was evaluated in a phantom study of 4 scans per single photon emission computerized tomography imaging modality. This was followed by 4 first in human translations into sentinel lymph node biopsy procedures for penile (open surgery) and prostate (laparoscopic surgery) cancer.

RESULTS

Overall the phantom studies revealed a tool-target distance accuracy of 2.1 mm for SPECT/CT and 3.2 mm for freehand single photon emission computerized tomography, and an augmented reality registration accuracy of 1.1 and 2.2 mm, respectively. Subsequently open and laparoscopic navigation efforts were accurate enough to localize the fluorescence signals of the targeted tissues in vivo.

CONCLUSIONS

The phantom and human studies performed suggested that the single navigation setup is applicable in various open and laparoscopic urological surgery applications. Further evaluation in larger patient groups with a greater variety of malignancies is recommended to strengthen these results.

Sentinel Lymphadenectomy in Vulvar Cancer Using Near-Infrared Fluorescence From Indocyanine Green Compared With Technetium 99m Nanocolloid

Objective

Nowadays, sentinel diagnostic is performed using technetium 99m (99mTc) nanocolloid as a radioactive marker and sometimes patent blue. In the last years, indocyanine green has been evaluated for sentinel diagnostic in different tumor entities. Indocyanine green is a fluorescent molecule that emits a light signal in the near-infrared band after excitation. Our study aimed to evaluate indocyanine green compared with the criterion-standard 99mTc-nanocolloid.

Methods

We included patients with primary, unifocal vulvar cancer of less than 4 cm with clinically node-negative groins in this prospective trial. Sentinel diagnostic was carried out using 99mTc-nanocolloid, indocyanine green, and patent blue. We examined each groin for light signals from the near-infrared band, for radioactivity, and for blue staining. A sentinel lymph node was defined as a 99mTc-nanocolloid–positive lymph node. All sentinel lymph nodes and all additional blue or fluorescent lymph nodes were excised and tested and then sent for histologic examination.

Results

In all, 27 patients were included in whom we found 91 sentinel lymph nodes in 52 groins. All these lymph nodes were positive for indocyanine green, also giving a sensitivity of 100% (95% confidence interval [CI], 96.0%–100%) compared with 99mTc-nanocolloid. Eight additional lymph nodes showed indocyanine green fluorescence but no 99mTc positivity, so that the positive predictive value was 91.9% (95% confidence interval, 84.6%–96.5%). In 1 patient, a false-negative sentinel missed by all 3 modalities was found.

Conclusions

Our results show that indocyanine green is a promising approach for inguinal sentinel identification in vulvar cancer with a similar sensitivity as radioactive 99mTc-nanocolloid and worth to be evaluated in further studies.

Indocyanine green fluorescence imaging of lymph nodes during robotic-assisted laparoscopic operation for endometrial cancer. A prospective validation study using a sentinel lymph node surgical algorithm

OBJECTIVE

A sentinel lymph node (SLN) strategy may have particular value in endometrial cancer (EC) because a therapeutic effect of lymphadenectomy per se is unproven. The aim was to evaluate indocyanine green (ICG) and near-infrared (NIR) fluorescence mapping using a surgical algorithm.

METHODS

From November 2012 through December 2015, women with apparently early stage EC underwent robot-assisted laparoscopic hysterectomy including ICG fluorescence SLN mapping following the Memorial Sloane Kettering Cancer Center (MSKCC) surgical algorithm.

RESULTS

Among 108 patients included, ≥1 SLNs was identified in 104 (96%), bilaterally in 84 (78%) and unilaterally in 20 patients (18%). Four patients failed SLN mapping. All SLN-positive patients had pelvic SLNs. Median number of nodes were 4.0 and 6.0 (p<0.001), when SLNs only and SLNs plus non-SLNs were removed, respectively. Lymph node metastases were detected in 17 patients (16%). One patient who failed SLN mapping had a non-SLN metastasis. The remaining 16 patients had metastases in SLNs, 12 in SLNs only and four in both SLNs and non-SLNs. Routine pathology detected 75% of patients with cancer positive SLNs while 25% were based on extended pathology. Lymph node metastases were found among 9% with low-, 11% with intermediate- and 32% with high-risk profiles, respectively.

CONCLUSIONS

We have reproduced the high total and bilateral SLN mapping using cervical ICG injection and NIR fluorescence. Practical application of the MSKCC algorithm allowed high lymph node metastasis detection in combination with a low extent of lymph node removal.