Indocyanine green fluorescence-navigated sentinel node biopsy showed higher sensitivity than the radioisotope or blue dye method, which may help to reduce false-negative cases in skin cancer

Transcutaneous sentinel lymph node detection in skin melanoma with near-infrared fluorescence imaging using indocyanine green

The aim of the study is to assess whether indocyanine green (ICG) fluorescence can replace technetium in the preoperative detection of sentinel lymph nodes (SLN) from cutaneous melanoma. The current golden standard for SLN detection is the radioisotope technetium. A promising alternative is fluorescence imaging (FLI) using ICG. In this study, we enrolled patients undergoing sentinel lymph node biopsy (SLNB) for skin melanoma at the Erasmus Medical Center between November 2022 and July 2023. The SLNB procedure was performed as a standard of care. After general anesthesia, ICG was injected intradermally around the primary tumor site. Both the patient and the surgeon were not blinded for the location of the SLN. FLI was performed before incision, in vivo after incision, and ex vivo. Fluorescent SLNs were confirmed using the gamma probe in all cases. Thirty-two patients were included in this study, and a total of 39 SLNs were harvested. The transcutaneous detection rate of ICG was 21.9%. The combined ex vivo ICG fluorescence and technetium uptake was 94.9%. One SLN contained only ICG (2.6%) and one SLN contained only technetium-uptake (2.6%). FLI using ICG resulted in a relatively low transcutaneous detection, which means that exclusive use of this technique in its present form is not feasible. However, we did find a high accumulation of ICG in the SLN, indicating the potential of ICG in combination with other imaging techniques.

Predictive value of methylene blue combined with indocyanine green in sentinel lymph node metastasis in breast cancer: a prospective pilot cohort study

Background

The status of sentinel lymph nodes is crucial for prognosis and treatment decisions in breast cancer patients. This study aimed to evaluate the predictive value of combined methylene blue and indocyanine green for sentinel lymph node metastasis in breast cancer.

Methods

This prospective cohort study enrolled 90 clinically node-negative breast cancer patients. Methylene blue and indocyanine green were injected locally before surgery. Sentinel lymph nodes were grouped based on fluorescence intensity and methylene blue staining. A binary logistic regression model was established using 285 lymph node groups to predict metastatic risk.

Results

A total of 475 lymph nodes were identified, with 33 being metastatic. The metastatic risk reached 70% for partially blue-stained and weakly fluorescent lymph nodes between 1-2 cm. The model revealed associations between lymph node size, dye staining patterns, and metastatic risks (P<0.05). The AUC of the ROC curve was 0.855.

Conclusions

The staining pattern of combined methylene blue and indocyanine green could predict risks of sentinel lymph node metastasis and facilitate rapid intraoperative identification of high-risk lymph nodes.

Infrared Fluorescence-guided Surgery for Tumor and Metastatic Lymph Node Detection in Head and Neck Cancer

In patients with head and neck cancer (HNC), surgical removal of cancerous tissue presents the best overall survival rate. However, failure to obtain negative margins during resection has remained a steady concern over the past 3 decades. The need for improved tumor removal and margin assessment presents an ongoing concern for the field. While near-infrared agents have long been used in imaging, investigation of these agents for use in HNC imaging has dramatically expanded in the past decade. Targeted tracers for use in primary and metastatic lymph node detection are of particular interest, with panitumumab-IRDye800 as a major candidate in current studies. This review aims to provide an overview of intraoperative near-infrared fluorescence-guided surgery techniques used in the clinical detection of malignant tissue and sentinel lymph nodes in HNC, highlighting current applications, limitations, and future directions for use of this technology within the field. Keywords: Molecular Imaging-Cancer, Fluorescence © RSNA, 2024.

Comparison of Different Techniques for the Assessment of Sentinel Lymph Node Biopsy in Melanoma: A Systematic Review

Background

The gold standard for sentinel lymph node staging in melanoma is the use of the combined technique of radioisotope plus blue dye. New techniques and alternative methods have been proposed, with the promise of achieving comparable efficacy. We then carried out a literature search.

Methods

We conducted a literature search using the "sentinel lymph node biopsy" and "melanoma" keywords, then selected the case-control studies (the quality of which was assessed using the STROBE criteria).

Results

Twelve studies of 13,017 were selected, concerning the identification rate of indocyanine green fluorescence and indocyanine green-99mtc-nanocolloid techniques. We have found a comparable identification rate between the various techniques, even if given the small population present for some techniques, the results did not reach statistical significance.

Conclusions

The use of new techniques in sentinel lymph node detection promises results comparable to the gold standard techniques, but further studies are needed to validate these methods in the context of melanoma surgery.

A novel, simple near-infrared thoracoscopic technique by a particular route for locating lung nodules

Background

The localization of pulmonary nodules prior to thoracoscopic surgery remains challenging for thoracic surgeons, especially for those nodules that are not visible or palpable on the lung surface. Our study is a simple and effective minimally invasive method using indocyanine green through a special pathway to locate pulmonary nodules and fluorescence thoracoscopic surgery.

Methods

Thoracoscopic surgery was performed for 18 undiagnosed peripheral non-solid nodules no larger than 2 cm after location. After 0.3 mg/kg indocyanine green was injected through the peripheral vein, the puncture needle was pulled out after it reached approximately 1 cm of the pulmonary parenchyma near the nodules. This was followed by transfer to the operating room. The nodule was initially localized by using a near-infrared thoracoscope to visualize indocyanine green fluorescence. Then, thoracoscopic resection was performed.

Results

Eighteen patients received this special and simple localization method, and underwent near-infrared, image-guided, video-assisted thoracoscopic surgery resection. Median computed tomography (CT) tumor size was 1.2 cm. Median depth from the pleural surface is 1.6 cm (range, 0.1-4.6 cm). The median time of CT-guided intervention was 12 min. The duration of thoracoscopic surgery was 67 min. Indocyanine green fluorescence was clearly identified in 17 of 18 patients (94.4%). The surgical margins were all negative on final pathology. The final diagnoses included 17 primary lung cancers, and 1 benign lung tumor.

Conclusions

CT-guided single puncture of indocyanine green after peripheral intravenous injection is a simple, effective, and safe method to locate the nodule. This offers surgeons the ease of localization through direct indocyanine green fluorescence imaging, and it can be used as an effective alternative to other placement methods of locating pulmonary nodules.

The Use of Indocyanine Green and Near-Infrared Fluorescence Imaging Versus Blue Dye in Sentinel Lymph Node Biopsy in Cutaneous Melanoma: A Retrospective, Cohort Study

BACKGROUND

The use of indocyanine green (ICG) and near-infrared fluorescence imaging is a promising option for sentinel lymph node (SLN) mapping in cutaneous melanoma. The study objective was to compare the performance of ICG and blue dye at detecting SLNs with radioisotope nanocolloid (technetium-99).

METHODS

Between April 2018 and June 2022, 293 consecutive patients with cutaneous melanoma (Breslow thickness ≥ 0.8 mm) underwent wide local excision and SLN biopsy. Patients were divided into group A (ICG; n = 122) and group B (blue dye; n = 163). All patients underwent SPECT/CT imaging preoperatively. SLN detection parameters and complications were compared between the groups.

RESULTS

A total of 285 patients had complete data and were included in the analysis. The median age was 62.0 (range 10-91) years, and 139 (48.8%) were female patients. The mean Breslow thickness was 2.6 mm, 89 (31.2%) patients had ulceration, and 179 (62.8%) patients had mitosis ≥ 1 mm2. The mean number of SLNs detected per patient in group A was 1.58 and group B was 1.48. In groups A and B, the SLN detection rate was 96.7% versus 89.6% (p = 0.022) and the pathological SLN detection rate was 92.3% versus 97.1% (p = 0.481), respectively.

CONCLUSIONS

ICG had a higher SLN detection rate and equal pathological SLN detection rate to blue dye. ICG may not be inferior to blue dye and is a useful adjunct to radioisotope in SLN biopsy in cutaneous melanoma.

Detection of Sentinel Lymph Nodes Using Indocyanine Green After Failing Scintigraphy in Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is a rare but highly aggressive skin cancer that carries a high rate of lymph node involvement and death. The National Comprehensive Cancer Network recommends sentinel lymph node (SLN) biopsy for the staging of the disease. Scintigraphy using radioactive isotopes (RI) such as technetium 99m (Tc99) remains the gold standard for the detection of SLNs, however, recently indocyanine green (ICG) fluorescence imaging has been used to aid in the detection of SLNs.We present the case of a patient who presented with MCC of the face and two SLNs successfully identified with ICG fluorescence despite the fact that they were not detected by intraoperative scintigraphy using Tc99. The use of ICG fluorescence imaging in MCC is safe and improves the ability to detect SLNs when combined with RI.

Comparison of indirect computed tomographic lymphography and near-infrared fluorescence sentinel lymph node mapping for integumentary canine mast cell tumors

OBJECTIVE

To compare the independent and combined use of indirect computed tomographic lymphography (ICTL) and near-infrared fluorescence (NIRF) for sentinel lymph node (SLN) mapping in dogs with integumentary mast cell tumors (MCT) and report the metastatic LN rate.

STUDY DESIGN

Prospective clinical study.

ANIMALS

Twenty client-owned dogs.

METHODS

Dogs underwent preoperative ICTL, then intraoperative NIRF SLN mapping and excision of the anatomic lymph node (ALN) and/or SLN, and primary MCT. Technique agreement was complete if the same SLN was detected, and partial if the same SLN was detected along with additional SLN. No agreement occurred if the techniques detected different or no SLN. MCT were graded using two- and three-tier schemes, and LN were graded from HN0-3; HN2-3 were considered metastatic.

RESULTS

Complete, partial, and no agreement between ICTL and NIRF was seen in 8/20 (40%), 8/20 (40%), and 4/20 (20%) dogs, respectively. Detection of ICTL-SLN and NIRF-SLN failed in 1/20 (5%) and 4/20 (20%), respectively. Tumors were grade II/low-grade in 19/20 (95%) and grade III/high-grade in 1/20 (5%) dogs. Nineteen out of 20 (95%) dogs had HN2-3 LN.

CONCLUSIONS

Technique agreement of at least one SLN was seen in 16/20 (80%) dogs. Although most MCT were classified as intermediate to low grade, LN metastases were commonly detected.

CLINICAL SIGNIFICANCE

Combining ICTL and NIRF for MCT SLN mapping yields high SLN detection rates. Lymph node metastasis may be more common than previously reported for intermediate to low grade MCT.

The Utility of Indocyanine Green Dye Fluorescence Lymphography and Angiography During Wide Excision of Cutaneous Melanoma

Background and Objectives. Lymph node status is the most important prognostic factor in cutaneous melanoma patients. Recent studies showed that indocyanine green (ICG) fluorescence lymphography helps locating sentinel nodes better. Sometimes, flap reconstruction is needed after wide excision of tumor. Indocyanine green fluorescence also simplifies the intraoperative design of flaps. This study investigates the use of ICG fluorescence in patients with cutaneous melanoma during operation. Methods. We performed a single-center, retrospective study of subjects with cutaneous melanoma using ICG lymphograhy and/or angiography during wide excision of tumor between 2015 and 2019. Patients received a dermal injection of ICG and patent blue (PB) dye. The positive node was excised. Indocyanine green angiography was utilized to visualize better skin paddle during flap reconstruction if needed. Results. A total of 37 sentinel lymph nodes (SLNs) were removed in 12 patients. Indocyanine green successful localization was found in 10 of the 12 patients (83%). Three patients were found with 6 metastatic nodes on final pathology. 100% of these 6 nodes were identified by ICG, while 83% (5/6) were positive PB. Three of the 12 patients received flap reconstruction after operation, and no major complications occurred. Conclusions. ICG dye lymphangiography is a good alternative for locating SLNs in patients with melanoma. It could also visualize well perfusion skin paddle during reconstruction. We reported a reproducible and simple method to utilize ICG fluorescence in cutaneous melanoma patients.

Transcutaneous sentinel lymph node detection in cutaneous melanoma with indocyanine green and near-infrared fluorescence: A diagnostic sensitivity study

Sentinel lymph node (SLN) biopsy with preoperative radiocolloid-based lymphoscintigraphy and blue dye injection is considered the standard procedure for staging nodal metastases in early-stage cutaneous melanoma patients with clinically uninvolved lymph nodes. While this combination renders good accuracy in SLN detection, radiation exposure and the frequent allergic reactions to the blue dye are considered drawbacks of this technique. Indocyanine green (ICG) is a water-soluble fluorescent dye that can be identified through near-infrared fluorescence imaging (NIRFI). The aim of this prospective diagnostic sensitivity study was to assess the feasibility of ICG and NIRFI to identify SLNs in melanoma transcutaneously ("before skin incision") and to analyze the various factors influencing detection rate, in comparison to lymphoscintigraphy. This study included 93 patients undergoing SLN biopsy for cutaneous melanoma. The region and the number of the SLNs identified with lymphoscintigraphy and with ICG were recorded. Patients' characteristics, as well as tumor details were also recorded preoperatively. One hundred and ninety-four SLNs were identified through lymphoscintigraphy. The sensitivity of ICG for transcutaneous identification of the location of the SLNs was 96.1% overall, while the sensitivity rate for the number of SLNs was 79.4%. Gender and age did not seem to influence detection rate, but a body mass index >30 kg/m2 was associated with a lower identification rate of the number of SLNs (P = .045). Transcutaneous identification of SLNs through ICG and NIRFI technology is a feasible technique that could potentially replace in selected patients the standard SLN detection methodology in cutaneous melanoma.

Management of Early-Stage Vulvar Cancer

Simple Summary

Vulvar cancer is a rare gynecological malignancy that affects mainly postmenopausal women. Recently, however, an alarming increase in the rates among young women has been observed due to human papillomavirus infection. The standard treatment for vulvar cancer is surgery with or without radiotherapy as adjuvant treatment. In recent decades, sentinel lymph node biopsy has been included as part of the surgical treatment. Thus, our objective was to review and discuss the advances found in the literature about early-stage vulvar cancer. For this, we searched PubMed for publications in the English language. Relevant articles, such as the GROINS-V studies, and the GOG protocols, are presented in this review exhibiting the evolution of early-stage vulvar cancer treatment and the decrease in surgical morbidity rates.

Abstract

Vulvar cancer is a rare gynecological malignancy since it represents 4% of all cancers of the female genital tract. The most common histological type is squamous cell carcinoma (90%). This type can be classified into two clinicopathological subtypes according to the etiology. The first subtype is associated with persistent human papillomavirus infection and is usually diagnosed in younger women. The second subtype is associated with lichen sclerosus condition, and in most cases is diagnosed in postmenopausal women. Currently, an increase in first subtype cases has been observed, which raised the concern about associated mortality and treatment morbidity among young women. Vulvar cancer treatment depends on histopathology grade and staging, but surgery with or without radiotherapy as adjuvant treatment is considered the gold standard. In recent decades, sentinel lymph node biopsy has been incorporated as part of the treatment. Therefore, we sought to review and discuss the advances documented in the literature about vulvar cancer focusing on the treatment of early-stage disease. Relevant articles, such as the GROINS-V studies and the GOG protocols, are presented in this review. Additionally, we discuss key points such as the evolution of treatment from invasive surgery with high morbidity, to more conservative approaches without compromising oncologic safety; the role of sentinel lymph node mapping in the initial staging, since it reduces the complications caused by inguinofemoral lymphadenectomy; the recurrences rates, since local recurrence is common and curable, however, groin-associated, or distant recurrences have a poor prognosis; and, finally, the long-term follow-up that is essential for all patients.

Fluorescent Tracers for In Vivo Imaging of Lymphatic Targets

The lymphatic system continues to gain importance in a range of conditions, and therefore, imaging of lymphatic vessels is becoming more widespread for research, diagnosis, and treatment. Fluorescent lymphatic imaging offers advantages over other methods in that it is affordable, has higher resolution, and does not require radiation exposure. However, because the lymphatic system is a one-way drainage system, the successful delivery of fluorescent tracers to lymphatic vessels represents a unique challenge. Each fluorescent tracer used for lymphatic imaging has distinct characteristics, including size, shape, charge, weight, conjugates, excitation/emission wavelength, stability, and quantum yield. These characteristics in combination with the properties of the target tissue affect the uptake of the dye into lymphatic vessels and the fluorescence quality. Here, we review the characteristics of visible wavelength and near-infrared fluorescent tracers used for in vivo lymphatic imaging and describe the various techniques used to specifically target them to lymphatic vessels for high-quality lymphatic imaging in both clinical and pre-clinical applications. We also discuss potential areas of future research to improve the lymphatic fluorescent tracer design.

The Use and Technique of Sentinel Node Biopsy for Skin Cancer

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the indications for and prognostic value of sentinel lymph node biopsy in skin cancer. 2. Learn the advantages and disadvantages of various modalities used alone or in combination when performing sentinel lymph node biopsy. 3. Understand how to perform sentinel lymph node biopsy in skin cancer patients.

SUMMARY

Advances in technique used to perform sentinel lymph node biopsy to assess lymph node status have led to increased accuracy of the procedure and improved patient outcomes.

The utility of ICG fluorescence for sentinel lymph node identification in head and neck melanoma

PURPOSE

Perform an evidence-based review to determine the utility of indocyanine green fluorescence (ICG) to detect sentinel lymph nodes (SLN) in patients with head and neck melanoma compared to blue dye or radiocolloid injection (RI).

MATERIALS AND METHODS

A systematic review of the literature was performed to identify patients with head and neck melanoma managed with ICG fluorescence. PubMed, Embase, and Cochrane Library databases were searched. Included studies were assessed for level of evidence. Patient demographics and data on SLN identification were determined.

RESULTS

Twenty-two studies encompassing 399 patients (75% male, 25% female, average age 57.1 years) met inclusion criteria. Publications comprised of two case reports, four retrospective case series, twelve cohort studies, and four clinical trials. Most common site of melanoma was scalp/temple/forehead (35%), cheek/midface (22%), and ear (17%) with an average Breslow thickness of 3.32 mm. SLN was identified in 80.7% (n = 201/249) of patients using ICG-RI, 85.2% (n = 75/88) using RI alone, and 63.4% (n = 52/82) using blue dye-RI.

CONCLUSIONS

ICG-^99mTc-nanocolloid hybrid tracer may be a superior alternative to blue dye + adiocolloid and has theoretical advantages compared to RI alone. Additional prospective randomized controlled trials are needed to further compare these methods and obtain data on false negative rates, operating room time, and cost effectiveness to fully elucidate the utility of ICG-^99mTc-nanocolloid over current methods used for SLN identification in this patient population.

Indocyanine Green Fluorescence Imaging with Lymphoscintigraphy Improves the Accuracy of Sentinel Lymph Node Biopsy in Melanoma

BACKGROUND

Despite advances in melanoma management, there remains room for improvement in the accuracy of sentinel lymph node biopsy. The authors analyzed a prospective cohort of patients with primary cutaneous melanoma who underwent sentinel lymph node biopsy with lymphoscintigraphy and indocyanine green fluorescence to evaluate the quality and accuracy of this technique.

METHODS

Consecutive primary cutaneous melanoma patients who underwent sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green fluorescence from 2012 to 2018 were prospectively enrolled. Analysis was performed of melanoma characteristics, means of identifying sentinel lymph nodes, sentinel lymph node status, and recurrence.

RESULTS

Five hundred ninety-four melanomas and 1827 nodes were analyzed; 1556 nodes (85.2 percent) were identified by radioactivity/fluorescence, 255 (14 percent) by radioactivity only, and 16 (0.9 percent) with indocyanine green only. There were 163 positive sentinel nodes. One hundred forty-seven (90.2 percent) were identified by radioactivity/fluorescence, 13 (8 percent) by radioactivity only, and three (0.6 percent) with fluorescence only. Of the 128 patients with a positive biopsy, eight patients' (6.3 percent) nodes were identified by radioactivity only and four (3.4 percent) with fluorescence only. There were 128 patients with a positive biopsy, 454 with a negative biopsy, and 12 patients who had a negative biopsy with subsequent nodal recurrence. Mean follow-up was 2.8 years.

CONCLUSIONS

In the study of the largest cohort of patients with primary cutaneous melanoma who underwent a sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green-based technology, the quality and accuracy of this technique are demonstrated. This has important implications for melanoma patients, as the adoption of this approach with subsequent accurate staging, adjuvant workup, and treatment may improve survival outcomes. .

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, II.

Diagnostic value of indocyanine green fluorescence guided sentinel lymph node biopsy in vulvar cancer: A systematic review

INTRODUCTION

Sentinel lymph node biopsy (SLN) helps define lymph node status, a major prognostic factor in vulvar cancer. The aim of the current systematic review was to assess the use of indocyanine green (ICG) coupled with near-infrared (NIR) fluorescence imaging in SLN mapping in vulvar cancer in terms of technique used, feasibility and accuracy.

DATA SOURCES

We performed a systematic review using bibliographic citations from PubMed, Clinical Trials.gov, Embase, Cochrane Library, and Web of Science databases. MeSH terms for SLN, ICG and vulvar cancer were combined and restricted to the English language. The final search was performed on May 28, 2020. The primary outcome was to determine if the use of ICG alone in detecting SLN in women with vulvar cancer is as accurate as the gold standard dual labeling technique.

RESULTS

Of the 34 studies initially identified, 13 were included for analysis. The SLN detection rate with ICG and NIR fluorescence ranged from 89.7 to 100%. No studies demonstrated the superiority of other detection techniques compared to ICG and NIR imaging. Lower SLN detection rates were found in studies with the most metastatic lymph nodes. No consensus was reached concerning the optimal use of ICG in terms of: injection timing or site; concentrations or volume of ICG; or use of human serum albumin or hybrid tracer. No adverse events were reported.

CONCLUSION

ICG for SLN mapping appears to be safe in women with vulvar cancer with a detection rate similar to the current techniques. A large prospective randomized controlled study with optimization of the technique is necessary to homogenize current practice and determine the true value of ICG in vulvar cancer.

PROSPERO ID

CRD42020178261.

Long term-follow-up multicenter feasibility study of ICG fluorescence-navigated sentinel node biopsy in oral cancer

In the current study, the utility of sentinel node (SN) identification using indocyanine green (ICG) was investigated for oral cancers in the clinical N0 stage. The current study was a prospective, multicentre, phase II clinical trial that was conducted in Japan. A total of 18 patients were included. Before surgery, the patients underwent lymphoscintigraphy to map the SNs. During surgery, radioactive isotope (RI) mapping was used to detect the SNs, and ICG was subsequently injected. ICG mapping of the SNs was then performed through the skin. The primary tumour was resected, and a neck flap was elevated for neck dissection, followed by SN biopsy (SNB) using RI or ICG mapping. With the RI method, a total of 63 SNs were detected. Among these SNs, 8 (12.7%) were positive for metastasis, including those with isolated tumour cells (ITCs). The median number of SNs per patient identified by SNB was 4. With the ICG method, a total of 67 SNs were detected. Among these SNs, 7 (10.4%) were positive for metastasis, including those with ITCs. The median number of SNs per patient identified by SNB was 4 (range, 1-6). The 5-year overall survival (OS) of all patients was 83.3%, and the 5-year disease-free survival (DFS) of all patients was 76.7%. The neck compression technique is a simple method that can be used to facilitate surgical procedures of ICG fluorescence navigated SNB for head and neck cancer.

Systematic review and meta-analysis concerning near-infrared imaging with fluorescent agents to identify the sentinel lymph node in oncology patients

Sentinel node procedures (SNP) are performed with the use of tracer-agents, mainly radio-colloid and/or blue dye. Fluorescent agents have emerged as a new tracer-agent to identify the SLN intra-operatively with near-infrared imaging. Our aim is to compare the detection rate of fluorescent agents to current "golden standards" (blue dye and/or radio-colloid) for the SNP by means of a systematic review and meta-analysis without any restrictions based on tumor type. A systematic search in PubMed, Embase and The Cochrane Library was performed. Articles that compared the detection rates of fluorescent agents with radio-colloid and/or blue dye were included. Meta-analyses were performed for breast, gynecological and dermatological cancer using a random effects model. In total 6195 articles were screened which resulted in a final inclusion of 55 articles. All studies used indocyanine green (ICG) as fluorescent agent. Meta-analyses comparing ICG with blue dye showed a significant and clinically relevant difference in detection rate in favor of ICG, for both breast, dermatological and gynecological cancer. Meta-analyses comparing ICG with radio-colloid did not show any significant differences, with the exception of ICG versus radio-colloid + blue dye for the bilateral SLN detection in gynecological cancer. Near-infrared fluorescence imaging using ICG provides a higher detection rate compared to blue dye for the SNP in a range of different tumor types. SLN detection rates of ICG are comparable to radio-colloid. Due to their complementary characteristics in terms of spatial resolution and transdermal sensitivity, we suggest to use a combination of both ICG and a radio-colloid.

Sentinel lymph node mapping with fluorescent and radioactive tracers in vulvar cancer patients

PURPOSE

Application of radioactive tracers for sentinel lymph node biopsy (SLNB) in vulvar cancer has been established, however, the use of radioisotopes is expensive and requires complex logistics. This exploratory study evaluated the feasibility of near-infrared fluorescence-based SLNB in comparison to the gold standard using radioactive guidance.

METHODS

At Evangelische Kliniken Essen-Mitte (Essen, Germany) between 02/2015 and 04/2019, 33 patients with squamous cell vulvar cancer and unifocal tumors (32 midline, 1 lateral) smaller than 4 cm underwent SLNB as part of their routine primary surgical therapy. Radiolabeled nanocolloid technetium 99 (99mTc) was injected preoperatively and indocyanine green (ICG) intraoperatively. Demographic and clinical data were retrieved from patients' records, and descriptive statistics were applied. The detection rate of the ICG fluorescence technique was compared with the standard radioactive approach.

RESULTS

In patients with midline tumors, bilateral SLNB was attempted. SLNB was feasible in 61/64 (95.3%) groins with 99mTc and in 56/64 (87.5%) with ICG. In total, 125 SLNs were excised; all SLNs were radioactive and 117 (93.6%) also fluorescent. In 8 patients with BMI > 30 kg/m2, SLNB was successful in 14/15 groins (93.3%) with 99mTc and 13/15 groins (86.7%) with ICG. Upon final histology, infiltrated nodes were present in 9/64 (14.1%) groins and 10/125 SLNs; one positive SLN was not detected with ICG.

CONCLUSIONS

SLNB using ICG is a promising technique, however, the detection rate obtained was slightly lower than with 99mTc. The detection rate increased over time indicating that experience and training may play an important role besides further methodological refinements.

Detection of Occult Metastases in Patients with T1 and T2 Stage Lower Lip Squamous Cell Carcinomas after Positive Lymphoscintigraphy

The aim of this study was to detect lower lip squamous cell carcinomas (SCC) that had metastasized to the lymph nodes and to evaluate if neck dissection was necessary for patients with T1 or T2-stage lip cancer after a sentinel lymph node biopsy (SLNB). The study was conducted as a prospective clinical study to detect occult neck metastases in patients with T1 or T2 stage SCC of the lower lip. Thirty-one patients were eligible and underwent echo-ultrasound, computer tomography, magnetic resonance and lymphoscintigraphy (LSG) as diagnostic procedures. LSG was performed on the same day as the surgical procedure, after intradermal injection of 37 Mbq Tc99m-Sn-colloid/mL at four peritumoral sites. In patients with positive LSG results, the sentinel lymph nodes were extracted surgically. The risk factors for cancer development were sun exposure and smoking. The highest accuracy for detecting lymph node enlargements was achieved with magnetic resonance imaging (MRI; 80.7%). LSG showed excellent sensitivity (100%) and negative predictive value (NPV; 100%). Overall, occult metastases were diagnosed with an SLNB in eight (25.8%) patients. According to the results, with great caution, we suggest that an SLNB is reasonable to initiate only for patients with positive sentinel nodes by positive LSG, to be used as a lower morbidity approach for selected patients with T1 and T2 stage cancers.

Near-infrared fluorescence imaging improves the nodal yield in neck dissection in oral cavity cancer - A randomized study

INTRODUCTION

Lymph node yield (LNY) in neck dissection has been identified as a prognostic factor in oral cavity cancer. The purpose of this study was to investigate the impact of additional use of optical imaging on LNY in therapeutic ND in oral cancer.

METHODS

Consecutive patients with oral squamous cell carcinoma with clinical neck metastasis planned for primary tumor resection were randomized to conventional neck dissection or near-infrared fluorescence (NIRF)-guided neck dissection, respectively. In the intervention group, patients were injected with ICG-Nanocoll prior to surgery. Intraoperatively, an optical hand-held camera system was used for lymph node identification. Also, NIRF imaging of the neck specimen was performed, and optical signals were pinned with needle markings to guide the pathological examination. The endpoint of the study was LNY per neck side in levels Ib-III.

RESULTS

31 patients were included with 18 neck sides in the control group and 18 neck sides in the intervention group for evaluation. During NIRF-guided ND, individual lymph nodes could be identified by a bright fluorescent signal and individual tumor-related drainage patterns could be observed in the neck. The LNY in the intervention group was significantly higher compared to the control group (p = 0.032) with a mean of 24 LN (range: 12-33 LN in levels Ib-III compared to 18 LN (range: 10-36 LN) in the control group, respectively.

CONCLUSIONS

NIRF-guided ND significantly improved the nodal yield compared to the control group. Intraoperative real-time optical imaging enabled direct visualization of tumor-related drainage patterns within the neck lymphatics.

Malignant Melanoma: Diagnostic and Management Update

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Summarize the changes to the American Joint Committee on Cancer Eighth Edition Melanoma Staging System. 2. List advances in genetic, molecular, and histopathologic melanoma diagnosis and prognostication. 3. Recommend sentinel lymph node biopsy and appropriate surgical margins based on individualized patient needs. 4. Recognize the currently available treatments for in-transit metastasis and advanced melanoma. 5. Describe current and future therapies for melanoma with distant visceral or brain metastases.

SUMMARY

Strides in melanoma surveillance, detection, and treatment continue to be made. The American Joint Committee on Cancer Eighth Edition Cancer Staging System has improved risk stratification of patients, introduced new staging categories, and resulted in stage migration of patients with improved outcomes. This review summarizes melanoma advances of the recent years with an emphasis on the surgical advances, including techniques and utility of sentinel node biopsy, controversies in melanoma margin selection, and the survival impact of time-to-treatment metrics. Once a disease manageable only with surgery, a therapeutic paradigm shift has given a more promising outlook to melanoma patients at any stage. Indeed, a myriad of novel, survival-improving immunotherapies have been introduced for metastatic melanoma and more recently in the high-risk adjuvant setting.

Sentinel lymph node biopsy in cutaneous melanoma of the head and neck using the indocyanine green SPY Elite system

PURPOSE

Lymph node status is the single most important prognostic factor for patients with early-stage cutaneous melanoma. Sentinel lymph node biopsy (SLNB) has become the standard of care for intermediate depth melanomas. Modern SLNB implementation includes technetium-99 lymphoscintigraphy combined with local administration of a vital blue dye. However, sentinel lymph nodes may fail to localize in some cases and false-negative rates range from 0 to 34%. Here we demonstrate the feasibility of a new sentinel lymph node biopsy technique using indocyanine green (ICG) and the SPY Elite near-infrared imaging system.

MATERIALS AND METHODS

Cases of primary cutaneous melanoma of the head and neck without locoregional metastasis, underwent SLNB at a single quaternary care institution between May 2016 and June 2017. Intraoperatively, 0.25 mL of ICG was injected intradermal in 4 quadrants around the primary lesion. 10-15 minute circulation time was permitted. SPY Elite identified the sentinel lymph node within the nodal basin marked by lymphoscintigraphy. Target first echelon lymph nodes were confirmed with a gamma probe and ICG fluorescence.

RESULTS

14 patients were included with T1a to T4b cutaneous melanomas. Success rates for sentinel lymph node identification using lymphoscintigraphy and the SPY Elite system were both 86%. Zero false negatives occurred. Median length of follow-up was 323 days.

CONCLUSIONS

In this pilot study, Indocyanine green near-infrared fluorescence demonstrates a safe, and facile method of sentinel lymph node biopsy for cutaneous melanoma of the head and neck compared with lymphoscintigraphy and vital blue dyes.

Eliminating Preoperative Lymphoscintigraphy in Extremity Melanomas

Background:

Preoperative lymphoscintigraphy (LSG) is an imaging procedure routinely used to identify the draining nodal basin in melanomas. At our institute, we have traditionally performed preoperative LSG followed by intraoperative LSG for logistical and evaluative reasons. We sought to determine if preoperative LSG could be safely eliminated in the treatment of extremity melanomas, which exhibit consistent and predictable lymphatic drainage patterns.

Methods:

We reviewed the Yale Melanoma Registry 1308012545 for cutaneous extremity melanomas treated at our institution. From this registry, we calculated the incidence of atypical lymph node drainage patterns outside the axillary and inguinal regions. Based on these data, we eliminated preoperative LSG in 21 cases (8 upper extremities and 13 lower extremities). Additionally, we calculated the potential hospital charge reduction of forgoing preoperative LSG.

Results:

Upper and lower extremity melanomas treated at our institution exhibited atypical lymph node drainage at a rate of 3.4% and 2.0%, respectively. The sites of atypical drainage were to the epitrochlear and popliteal regions. In all 21 cases where preoperative LSG was eliminated, we were able to correctly identify the sentinel lymph node. The potential hospital charge reduction of forgoing preoperative LSG totaled $2,393.

Conclusions:

Preoperative LSG can be safely eliminated in the management of upper and lower extremity melanomas. Exceptions may be considered for primary lesions of the posterior calf, ankle, and heel as well as for patients with history of prior surgery or radiation. Forgoing preoperative LSG results in a hospital charge reduction of $2,393 and provides additional benefits to the patient. Ultimately, there is potential for significant charge reduction if applied across health care systems.

A Comparison of Dye Versus Fluorescence Methods for Sentinel Lymph Node Mapping in Endometrial Cancer

OBJECTIVE

Sentinel nodes (SNs) have been observed in several reports from Japan and overseas in cases with endometrial cancer; however, no consensus has been reached regarding the types of tracers or the method of their injection. A combination of the radioisotope (RI) and dye method is considered to be desirable. We assessed SN mapping using either dye or near-infrared fluorescence imaging to clarify a suitable method in cases of endometrial cancer.

METHODS

Patients were enrolled from 92 patients diagnosed with endometrial cancer and having no extrauterine metastasis by the preoperative imaging between 2009 and 2014 at our institution. To identify the SNs, we performed 3 methods using either dye or fluorescence solutions in conjunction with a RI method. In the dye method, we injected indocyanine green in the uterine subserosa, visually identifying SNs as stained green. In the fluorescence method, a dilute indocyanine green solution (0.5 mg, fluorescence A or 0.25 mg, fluorescence B, each per 10 mL of solvent) was injected and the SN identified by the HyperEye Medical System.

RESULTS

The SN detection rates were 100%, 100%, and 96% using dye and fluorescence A or B solution, respectively. Pelvic SNs were detected by the 3 methods in 98%, 100%, and 96% of cases and para-aortic SNs in 65%, 88%, and 74%, respectively. Fluorescence A solution was somewhat better than dye in detecting para-aortic SNs, although not significantly so (P = 0.07). The sensitivity and negative predictive values for detecting SNs with metastases with the dye method were 92% and 98% compared with 100% and 100%, respectively, for both fluorescence solutions.

CONCLUSIONS

Although both dye and fluorescence methods performed well, no method perfectly identified para-aortic SNs. The concomitant use of the RI method is required to detect para-aortic SNs.

Usefulness of fluorescence vascular imaging for evaluating splenic perfusion

BACKGROUND

The aim of this study was to confirm whether intraoperative fluorescence vascular imaging using indocyanine green (FVI-ICG) is useful for evaluating splenic perfusion after spleen-preserving distal pancreatectomy (SPDP) performed with the Warshaw technique (SPDP-W).

METHODS

We evaluated the blood perfusion of the spleen with an intraoperative FVI-ICG system after SPDP-W. All of the patients underwent dynamic computed tomography (CT) scans at one post-operative week and one post-operative month to evaluate the post-operative blood perfusion of the spleen. Then, the post-operative perfusion status of the spleen according to CT and the intraoperative fluorescence status of the spleen were compared.

RESULTS

Five patients were enrolled in this study. None of the patients required secondary splenectomies. We detected a tendency towards a close relationship between the intraoperative fluorescence level of the spleen according to FVI-ICG performed after SPDP-W and post-operative splenic perfusion as evaluated by CT. Improved splenic perfusion was seen at one post-operative month in all cases, including a case in which poor splenic perfusion was initially detected.

CONCLUSION

We detected a close relationship between the fluorescence level of the spleen on intraoperative FVI-ICG and the post-operative perfusion status of the spleen among patients who underwent SPDP-W. Intraoperative FVI-ICG could help surgeons to safely preserve the spleen after SPDP-W.

Use of Indocyanine Green for Sentinel Lymph Node Biopsy: Case Series and Methods Comparison

Introduction:

Sentinel lymph node biopsy is indicated for patients with biopsy-proven thickness melanoma greater than 1.0 mm. Use of lymphoscintigraphy along with vital blue dyes is the gold standard for identifying sentinel lymph nodes intraoperatively. Indocyanine green (ICG) has recently been used as a method of identifying sentinel lymph nodes. We herein describe a case series of patients who have successfully undergone ICG-assisted sentinel lymph node biopsy for melanoma. We compare 2 imaging systems that are used for ICG-assisted sentinel lymph node biopsy.

Methods:

Fourteen patients underwent ICG-assisted sentinel lymph node biopsy for melanoma using the SPY Elite system (Novadaq, Mississigua, Canada) and the Hamamatsu PDE-Neo probe system (Mitaka USA, Park City, Utah). We analyzed costs for 2 systems that utilize ICG for sentinel lymph node biopsies.

Results:

Intraoperative use of ICG for sentinel lymph node biopsies was successful in correctly identifying sentinel lymph nodes. There was no difference between the Hamamatsu PDE-Neo probe and SPY Elite systems in the ability to detect sentinel lymph nodes; however, the former was associated with a lower operating cost and ease of use compared with the latter.

Conclusion:

ICG-assisted sentinel lymph biopsy using the SPY Elite or the Hamamatsu PDE-Neo probe systems for melanoma are comparable in terms of sentinel node detection. The Neo probe system delivers pertinent clinical data with the advantages of lower cost and ease of operation.

Indocyanine green applications in plastic surgery: A review of the literature

INTRODUCTION

Use of indocyanine green (ICG) near-infrared fluorescence as a dye to assess tissue vascularization is now well standardized. The aim of this literature review was to review and resume the most recent recommendations for ICG use in its plastic surgery applications.

METHODS

A systematic literature review was performed using Medline, EMBASE, and PubMed databases to obtain the latest recommendations for ICG in plastic surgery. Inclusion criteria were all articles written in English language that evaluated pre-, intra-, or postoperative ICG applications in surgical procedures usually performed by plastic surgeons. Case reports, reviews, meta-analyses, and experimental studies on animals or cadavers were excluded after title and abstract screening.

RESULTS

Of the 1389 article titles retrieved, 41 full-text articles met the inclusion criteria. ICG applications in plastic surgery were ICG lymphangiography used in sentinel lymph node mapping for breast cancer and melanoma and in microsurgery for the staging and treatment of secondary chronic lymphedema. The latest updates of ICG angiography in assessing free flaps, pedicled flaps, or large skin paddles were also retrieved.

CONCLUSIONS

Large prospective studies suggest that ICG lymphography could be used as a single tracer to reliably perform sentinel lymph node biopsy. In the case of cutaneous melanoma, ICG lymphography increases node detection sensitivity and accuracy in conjunction with lymphoscintigraphy. In chronic lymphedema, it is useful for pre- and postoperative staging and intraoperative anatomical location of lymphatic pathways when lymphovenous bypass is indicated. ICG angiography is used intraoperatively to assess free flap anastomosis and design skin paddles and postoperatively to monitor buried flaps. In pedicled perforator flaps or for large skin paddles, intraoperative ICG angiography is strongly correlated with postoperative outcomes.

LEVEL OF EVIDENCE

3.

Usefulness of Fluorescence Vascular Imaging for Preserving the Remnant Stomach After Distal Pancreatosplenectomy: A Case Report

Due to recent developments in medical treatment, the number of patients that undergo multiple surgical procedures for secondary metachronous cancer is increasing. In cases in which patients undergo distal pancreatosplenectomy after distal gastrectomy, surgeons might have concerns about whether they are able to preserve the remnant proximal stomach because the main feeding vessels will have been divided in the previous procedure. Herein, we report a case in which a patient underwent distal pancreatosplenectomy 20 years after undergoing distal gastrectomy, and the remnant proximal stomach was successfully preserved with the help of intraoperative fluorescence vascular imaging using indocyanine green (FVI-ICG). A 65-year-old female was referred to our hospital due to upper gastric pain and was diagnosed with cancer of the pancreatic body. She had undergone distal gastrectomy 20 years earlier for early stage gastric cancer. Therefore, the blood supply to the remnant stomach left after the distal pancreatectomy procedure might have been insufficient. To determine the adequacy of the blood supply to the remnant proximal stomach after distal pancreatosplenectomy, we conducted intraoperative FVI-ICG. Because strong fluorescence was detected, we were able to safely preserve the remnant stomach. At 4 and 8 months after surgery, computed tomography showed good blood flow through the remnant stomach. FVI-ICG is useful for evaluating the blood supply to tissues, and hence, can be used to predict the blood supply of residual organs.

Factors Affecting Blood Flow at the Tip of the Reconstructed Gastric Tube During Esophagectomy: A Study Using Indocyanine Green Fluorescence Angiography

The objective of this study was to clarify the factors affecting blood flow at the tip of the gastric tube during esophagectomy using indocyanine green (ICG) fluorescence angiography. The time until enhancement of the gastric tube tip determined using ICG fluorescence imaging is a useful indicator of blood flow, and has been shown not to differ significantly according to the connection status of the right or left gastroepiploic artery. Using ICG fluorescence imaging, the time until enhancement of the gastric tube tip was measured in 50 patients undergoing esophagectomy. Blood flow at the gastric tube tip was compared between 2 groups of patients: those in whom a connecting vessel from the left gastro-epiploic artery to the short gastric artery (l-s GA) was present and those in whom it was absent. The factors affecting blood flow to the gastric tube tip were also investigated using univariate and multivariate logistic regression analysis. The median time taken for the gastric tube tip to show enhancement with ICG was significantly shorter in the group with an l-s GA connection (P = 0.02). Multivariate analysis showed that the absence of an l-s GA connection (P = 0.04) and presence of arteriosclerosis-related disease (P = 0.02) were significant independent factors that delayed blood flow to the gastric tube. It is essential to preserve the whole vessel arcade of the greater curvature to achieve good perfusion of the gastric tube with blood. The presence of arteriosclerosis-related disease is a major factor affecting the safety of anastomosis during gastric tube reconstruction.

Optimal settings and accuracy of indocyanine green fluorescence imaging for sentinel node biopsy in early gastric cancer

Indocyanine green (ICG) fluorescence imaging represents a promising method for sentinel node (SN) biopsy in laparoscopic gastric surgery due to its signal stability. In the present study, the suitability and optimal settings of ICG fluorescence imaging for SN biopsy in early gastric cancer were determined. Patients with single primary superficial-type adenocarcinoma of the stomach, lesions <5 cm in diameter, and no evident nodal metastasis and out of indication for endoscopic submucosal dissection were enrolled. The day prior to surgery, ICG solution was endoscopically injected into four quadrants of the submucosal layer of the tumor. The Photodynamic Eye was used to detect ICG fluorescence. Bright nodes were defined as clearly fluorescent nodes. A total of 72 patients were enrolled; 11 cases presented with metastasis, and of these, 10 could be diagnosed by bright node biopsy. The adequate concentration and injection volume of ICG was determined to be 50 µg/ml (×100) and 0.5 mlx4 points, respectively. There was 1 false-negative case, and this was attributed to the failure of the frozen section diagnosis. These results suggested that ICG fluorescence imaging for SN biopsy in laparoscopic surgery for early gastric cancer is feasible. However, a weakness of ICG fluorescence imaging is the subjectivity of bright node evaluation.

A systematic review and meta-analyses of sentinel lymph node identification in breast cancer and melanoma, a plea for tracer mapping

PURPOSE

Sentinel lymph node biopsy (SLNB) has become a widely accepted staging procedure for both breast carcinoma and melanoma. The aim of our study was to systematically review different SLNB techniques and perform a meta-analysis for corresponding identification and false-negative rates.

METHODS

A systematic review of the literature on SLNB in patients with early stage breast carcinoma and melanoma was performed. Only original study groups were included. The SLN identification rate and false negative rate were pooled for patients with breast carcinoma or melanoma according to radiocolloid tracer, blue dye, indocyanine green (ICG), or a combination of a radiocolloid tracer with blue dye or ICG.

RESULTS

Between 1992 and 2012, a total of 154 studies (88 breast carcinoma and 66 melanoma) were reported that met our eligibility criteria. These studies included a total of 44,172 patients. The pooled SLN identification rate in breast carcinoma and melanoma patients using solely blue dye was 85% (range: 65-100%) and 84% (range: 59-100%), while for radiocolloid alone it was 94% (range: 67-100%) and 99% (range: 83-100%), respectively. Using a combination of radiocolloid and blue, identification rates were 95% (range 94-95%) and 98% (range: 98-98%).

CONCLUSIONS

The current meta-analysis provides data that favors the use of radiocolloid or radiocolloid combined with a blue dye for SLN identification. Performing SLNB with radiocolloid alone is the technique of choice for experienced surgeons, since blue dye has multiple disadvantages. SLNB using ICG as a fluorescent dye seems a promising technique for the near future.

Current Trends and Emerging Future of Indocyanine Green Usage in Surgery and Oncology: An Update

BACKGROUND

Indocyanine green (ICG) is a widely available dye of clinical importance that has been used for more than 50 years. Near-infrared (NIR) ICG fluorescence imaging has found a niche in cancer care since 2005, and was reviewed in 2011. There is a need for a comprehensive update and we aim to provide this through a review of the most recent literature.

METHODS

A systematic review of the literature using PubMed, EMBASE, and MEDLINE databases of articles published from 2000 to June 2015 evaluated topics pertinent to NIR fluorescence imaging with ICG in the diagnosis and surgical treatment of cancer. Articles previously referenced in a 2011 review and a 2015 meta-analysis were excluded, while articles that referenced future directions and economics were included in this current review.

RESULTS

Since 2011, the literature has grown exponentially, with significant advances at the molecular level. Significant findings from 89 select articles and 10 reviews, most of which were published between 2011 and 2015, are summarized. Preclinical studies are currently underway investigating tumor-specific fluorescence and targeted therapeutic delivery. The potential for ICG exists at every level of cancer care, from diagnosis to surveillance.

CONCLUSION

The indications, applications, and potential for ICG have grown exponentially in the past decade; an updated review of the literature is overdue and we present the most comprehensive review to date.

Evaluation of a radioactive and fluorescent hybrid tracer for sentinel lymph node biopsy in head and neck malignancies: prospective randomized clinical trial to compare ICG-(99m)Tc-nanocolloid hybrid tracer versus (99m)Tc-nanocolloid

PURPOSE

There is some controversy about the value of sentinel lymph node excision (SLNE) in patients with head and neck malignancies. The gold standard for detection and targeted extirpation of the SLN is lymphoscintigraphy with (99m)Tc-nanocolloid. The purpose of this prospective randomized study was to analyse the feasibility and clinical benefit of a hybrid tracer comprising the near-infrared (NIR) fluorescent indocyanine green (ICG) and (99m)Tc-nanocolloid (ICG-(99m)Tc-nanocolloid) in direct comparison with standard (99m)Tc-nanocolloid for guiding SLNE in patients with head and neck cutaneous malignancies.

METHODS

We analysed the data from 40 clinically lymph node-negative patients with melanoma, high-risk cutaneous squamous cell carcinoma, Merkel cell carcinoma or sweat gland carcinoma who underwent SLNE with ICG-(99m)Tc-nanocolloid (cohort A) or with the standard (99m)Tc-nanocolloid (cohort B).

RESULTS

Overall SLNs were identified preoperatively in all 20 patients (100%) in cohort A and in 18 of 20 patients (90%) in cohort B. The SLN basin was detected preoperatively in 18 patients (90%) in cohort A and also in 18 patients (90%) in cohort B. SLNs were identified intraoperatively in all 20 patients (100%) in cohort A and in 19 patients (95%) in cohort B (p = 0.487). Metastatic SLNs were detected in 9 patients (22.5%), 3 (15.0%) in cohort A and 6 (30.0%) in cohort B (p = 0.228).

CONCLUSION

The hybrid tracer ICG-(99m)Tc-nanocolloid is an innovative imaging tracer, reliably and readily providing additional information for the detection and excision of SLN in the head and neck region. Therefore, SLNE with combined radioactive and NIR fluorescence guidance is an attractive option for improving the SLN detection rate in patients with cutaneous head and neck malignancies.