Sentinel Lymph Node Biopsy in Breast Cancer Patients by Means of Indocyanine Green Using the Karl Storz VITOM® Fluorescence Camera

Staff radiation doses during Sentinel Lymph Node procedure of breast cancer from injection to surgeon

The Sentinel Lymph Node (SLN) or Sentinel Lymph Node Biopsy (SLNB) technique involves various professionals from different departments in clinical settings to manage breast cancer patients properly. Tracing the nodular involvement of breast cancer patients requires radiation source Tc99m labeled with colloidal albumin to be injected at the tumor site. The patient becomes a radiation source for a sufficient time, which concerns the Nuclear Medicine (NM) and surgical staff. The study aims to provide the radiation doses of staff in the NM department during the SLN scintigraphy procedure and obtain an empirical model for calculating the radiation doses to staff in the surgical department from that particular patient. Radiation doses in SLN technique for breast cancer patients are minimal, and a sufficient number of SLN biopsy procedures can be performed by hospital staff within the category of non-radiation workers.

Activity-Based Fluorescence Diagnostics for Cancer

Fluorescence imaging is one of the most promising approaches to achieve intraoperative assessment of the tumor/normal tissue margins during cancer surgery. This is critical to improve the patients' prognosis, and therefore various molecular fluorescence imaging probes have been developed for the identification of cancer lesions during surgery. Among them, "activatable" fluorescence probes that react with cancer-specific biomarker enzymes to generate fluorescence signals have great potential for high-contrast cancer imaging due to their low background fluorescence and high signal amplification by enzymatic turnover. Over the past two decades, activatable fluorescence probes employing various fluorescence control mechanisms have been developed worldwide for this purpose. Furthermore, new biomarker enzymatic activities for specific types of cancers have been identified, enabling visualization of various types of cancers with high sensitivity and specificity. This Review focuses on recent advances in the design, function and characteristics of activatable fluorescence probes that target cancer-specific enzymatic activities for cancer imaging and also discusses future prospects in the field of activity-based diagnostics for cancer.

Indocyanine green fluorescence versus blue dye, technetium-99M, and the dual-marker combination of technetium-99M + blue dye for sentinel lymph node detection in early breast cancer-meta-analysis including consistency analysis

BACKGROUND

Axillary sentinel lymph node biopsies are standard of care in patients with breast cancer and no clinically apparent metastases. Traditionally, technetium-99m, blue dye, or both have been used to identify sentinel lymph nodes. However, blue dyes miss up to 40% of sentinel lymph nodes, while technetium-99m use is complex, costly, and exposes patients to radiation. Over the past decade, studies have consistently found the biologically inert fluorescent indocyanine green to be 95% to 100% sensitive in detecting breast cancer sentinel lymph nodes, yet indocyanine green remains infrequently used.

METHODS

We conducted an extensive meta-analysis comparing indocyanine green against blue dye, technetium-99m, and the dual-marker combination of technetium-99m + BD. Unlike prior meta-analyses that only assessed either per-case or per-node sentinel lymph node detection, we analyzed the following 5 metrics: per-case and per-node sentinel lymph node detection and metastasis-positive sentinel lymph node sensitivity, and mean number of sentinel lymph nodes/case. We further examined the consistency and magnitude of between-study superiority and statistically significant within-study superiority of each marker against others.

RESULTS

For every metric and analysis approach, indocyanine green was clearly superior to blue dye and at least non-inferior, if not superior, to technetium-99m and technetium-99m + blue dye. Assessing the consistency of superiority by at least 2.0%, indocyanine green was superior to blue dye 73 times versus 1, to technetium-99m 42 times versus 9, and to technetium-99m + blue dye 6 times versus 0. Within-study statistically significant differences favored indocyanine green over blue dye 29 times versus 0 and over technetium-99m 11 times versus 2.

DISCUSSION

For sentinel lymph node detection in patients with breast cancer with no clinically apparent metastases, indocyanine green is clearly and consistently superior to blue dye and either non-inferior or superior to technetium-99m and technetium-99m + blue dye.

Current and Developing Lymphatic Imaging Approaches for Elucidation of Functional Mechanisms and Disease Progression

Study of the lymphatic system, compared to that of the other body systems, has been historically neglected. While scientists and clinicians have, in recent decades, gained a better appreciation of the functionality of the lymphatics as well as their role in associated diseases (and consequently investigated these topics further in their experimental work), there is still much left to be understood of the lymphatic system. In this review article, we discuss the role lymphatic imaging techniques have played in this recent series of advancements and how new imaging techniques can help bolster this wave of discovery. We specifically highlight the use of lymphatic imaging techniques in understanding the fundamental anatomy and physiology of the lymphatic system; investigating the development of lymphatic vasculature (using techniques such as intravital microscopy); diagnosing, staging, and treating lymphedema and cancer; and its role in other disease states.

Evolution of Indocyanine Green Fluorescence in Breast and Axilla Surgery: An Australasian Experience

The evolution of indocyanine green (ICG) fluorescence in breast and axilla surgery from an Australasian perspective is discussed in this narrative review with a focus on breast cancer and reconstruction surgery. The authors have nearly a decade of experience with ICG in a high-volume institution, which has resulted in publications and ongoing future research evaluating its use for predicting mastectomy skin flap perfusion for reconstruction, lymphatic mapping for sentinel lymph node (SLN) biopsy, and axillary reverse mapping (ARM) for prevention of lymphoedema. In the authors' experience, routine use of ICG angiography during breast reconstruction postmastectomy was demonstrated to be cost-effective for the reduction of ischemic complications in the Australian setting. A novel tracer combination, ICG-technetium-99m offered a safe and effective substitute to the "gold standard" dual tracer for SLN biopsy, although greater costs were associated with ICG. An ongoing trial will evaluate ARM node identification using ICG fluorescence during axillary lymph node dissection and potential predictive factors of ARM node involvement. These data add to the growing literature on ICG and allow future research to build on this to improve understanding of the potential benefits of fluorescence-guided surgery in breast cancer and reconstruction surgery.

Clinical use of Indocyanine green fluorescence method for sentinel lymph node biopsy in breast cancer in France in 2021

INTRODUCTION

Indocyanine green (ICG) for axillary sentinel lymph node (SLN) detection in early breast cancer is at least equivalent to radioisotopic and/or colorimetric techniques. This procedure has not yet been recommended by learned societies in France. Following the recent drug approval of Infracyanin ® in this indication, we wished to study the use of ICG in France.

METHODS

We conducted a web-based survey among members of multiple French breast cancer societies throughout November 2021. The survey assessed the profile of the respondent, the use or not of ICG for the detection of SLN in breast cancer, the technique used and the opinion of non-users and their expectations on the subject.

RESULTS

Seventy-five surgeons participated. More than a third (37 %) have been using ICG for the detection of SLN in breast cancer for 2 to 3 years. Technique was highly variable. According to 82.1 % of the respondents, less than 20 procedures are necessary to master the use of ICG. The main advantage reported for this method is the reduction of organizational constraints. The obstacles to the use of the ICG are the near infra-red camera equipment, but also the lack of validation by the French guidelines. Among non-users, 83 % would like to develop this technique in their center and 72.3 % are interested in training on this subject.

CONCLUSION

This work highlights the need for French learned societies to take a stand on this issue but also the need to carry out studies on the technical aspects in order to standardise practices.

An Updated Review on the Emerging Role of Indocyanine Green (ICG) as a Sentinel Lymph Node Tracer in Breast Cancer

Sentinel lymph node biopsy (SLNB) has become the standard of care for clinically node-negative breast cancer and has recently been shown by clinical trials to be also feasible for clinically node-positive patients treated with primary systemic therapy. The dual technique using both radioisotope (RI) and blue dye (BD) as tracers for the identification of sentinel lymph nodes is considered the gold standard. However, allergic reactions to blue dye as well as logistics issues related to the use of radioactive agents, have led to research on new sentinel lymph node (SLN) tracers and to the development and introduction of novel techniques in the clinical practice. Indocyanine green (ICG) is a water-soluble dye with fluorescent properties in the near-infrared (NIR) spectrum. ICG has been shown to be safe and effective as a tracer during SLNB for breast cancer and accumulating evidence suggests that ICG is superior to BD and at least comparable to RI alone and to RI combined with BD. Thus, ICG was recently proposed as a reliable SLN tracer in some breast cancer clinical practice guidelines. Nevertheless, there is lack of consensus regarding the optimal role of ICG for SLN mapping. Specifically, it is yet to be determined whether ICG should be used in addition to BD and/or RI, or if ICG could potentially replace these long-established traditional SLN tracers. This article is an updated overview of somerecent studies that compared ICG with BD and/or RI regarding their accuracy and effectiveness during SLNB for breast cancer.

Novel Dual Tracer Indocyanine Green and Radioisotope Versus Gold Standard Sentinel Lymph Node Biopsy in Breast Cancer: The GREENORBLUE Trial

BACKGROUND

The methods for sentinel lymph node (SLN) biopsy in breast cancer have been variable in type and number of tracers. Some units have abandoned the use of blue dye (BD) due to adverse reactions. Fluorescence-guided biopsy with indocyanine green (ICG) is a relatively novel technique. This study compared the clinical efficacy and costs between novel dual tracer ICG and radioisotope (ICG-RI) with "gold standard" BD and radioisotope (BD-RI).

METHODS

Single-surgeon study of 150 prospective patients with early breast cancer undergoing SLN biopsy (2021-2022) using ICG-RI compared with a retrospective cohort of 150 consecutive previous patients using BD-RI. Number of SLNs identified, rate of failed mapping, identification of metastatic SLNs, and adverse reactions were compared between techniques. Cost-minimisation analysis performed by using Medicare item numbers and micro-costing analysis.

RESULTS

Total number of SLNs identified with ICG-RI and BD-RI was 351 and 315, respectively. Mean number of SLNs identified with ICG-RI and BD-RI was 2.3 (standard deviation [SD] 1.4) and 2.1 (SD 1.1), respectively (p = 0.156). There were no cases of failed mapping with either dual technique. Metastatic SLNs were identified in 38 (25.3%) ICG-RI patients compared with 30 (20%) BD-RI patients (p = 0.641). There were no adverse reactions to ICG, whereas four cases of skin tattooing and anaphylaxis were associated with BD (p = 0.131). ICG-RI cost an additional AU$197.38 per case in addition to the initial cost for the imaging system.

CLINICAL TRIAL REGISTRATION

 ACTRN12621001033831.

CONCLUSIONS

Novel tracer combination, ICG-RI, provided an effective and safe alternative to "gold standard" dual tracer. The caveat was the significantly greater costs associated with ICG.

Assessment of open-field fluorescence guided surgery systems: implementing a standardized method for characterization and comparison

Significance

Fluorescence guided surgery (FGS) has demonstrated improvements in decision making and patient outcomes for a wide range of surgical procedures. Not only can FGS systems provide a higher level of structural perfusion accuracy in tissue reconstruction cases but they can also serve for real-time functional characterization. Multiple FGS devices have been Food and Drug administration (FDA) cleared for use in open and laparoscopic surgery. Despite the rapid growth of the field, there has been a lack standardization methods.

Aim

This work overviews commonalities inherent to optical imaging methods that can be exploited to produce such a standardization procedure. Furthermore, a system evaluation pipeline is proposed and executed through the use of photo-stable indocyanine green fluorescence phantoms. Five different FDA-approved open-field FGS systems are used and evaluated with the proposed method.

Approach

The proposed pipeline encompasses the following characterization: (1) imaging spatial resolution and sharpness, (2) sensitivity and linearity, (3) imaging depth into tissue, (4) imaging system DOF, (5) uniformity of illumination, (6) spatial distortion, (7) signal to background ratio, (8) excitation bands, and (9) illumination wavelength and power.

Results

The results highlight how such a standardization approach can be successfully implemented for inter-system comparisons as well as how to better understand essential features within each FGS setup.

Conclusions

Despite clinical use being the end goal, a robust yet simple standardization pipeline before clinical trials, such as the one presented herein, should benefit regulatory agencies, manufacturers, and end-users to better assess basic performance and improvements to be made in next generation FGS systems.

High-Definition 3-D Exoscope for Micro-Laryngeal Surgery: A Preliminary Clinical Experience in 41 Patients

OBJECTIVE

The aim of this prospective clinical study is to evaluate the feasibility of the micro-laryngeal surgery (MLS) using a 3D operating exoscope (OE) in substitution to a conventional operating microscope (OM).

METHODS

A total of 41 consecutive patients were included (male: 26; median age: 55.0 years; IQR: 46.0-68.0). After each procedure, the surgeon and the scrub nurse were asked to fill out a tailored questionnaire on a 3-point Likert scale (1-not acceptable, 2-acceptable, 3-good) including 12 items.

RESULTS

The majority of the procedures were therapeutic (n = 31, 75.6%), while the remaining were diagnostic (n = 10, 24.4%). All surgeries were successfully completed without the support of the OM, and no complications or unwanted delays were detected. The majority of the individual items were judged "good" either by surgeons (n = 399, 81.1%) and scrub nurses (n = 287, 87.5%). The natural posture during the procedure, and the ease of use the joystick and focusing were the best-rated items by the surgeons.

CONCLUSIONS

This study demonstrates the feasibility of MLS using the OE. Further comparative clinical studies are needed to clarify its real value in substitution to a conventional operating microscope and to better define advantages and disadvantages.

Indocyanine green: An old drug with novel applications

Indocyanine green (ICG), a US Food and Drug Administration-approved fluorescent compound, has been on the medical stage for more than 60 years. Current uses include hepatic function evaluation before surgical procedure and fundus evaluation. The large safety margin and near-infrared fluorescent optical advantage of the drug have proved useful in several clinical trials of intraoperative systems for tumor removal. Several nanoparticle-sized formulations for thermal ablation and photodynamic therapy have also been evaluated in animal experiments. Studies have attempted to manipulate ICG as a reporter fluorophore with initial success. In this article, we reviewed ICG's histological applications, chemical and physical properties, current clinical applications, ongoing clinical trials, and biomedical studies and prospects. We believe that ICG could be used with novel biotechnological techniques, such as fluorescent endoscopy and photoacoustic equipment, in a range of biomedical fields.

Targeted optical fluorescence imaging: a meta-narrative review and future perspectives

Purpose

The aim of this review is to give an overview of the current status of targeted optical fluorescence imaging in the field of oncology, cardiovascular, infectious and inflammatory diseases to further promote clinical translation.

Methods

A meta-narrative approach was taken to systematically describe the relevant literature. Consecutively, each field was assigned a developmental stage regarding the clinical implementation of optical fluorescence imaging.

Results

Optical fluorescence imaging is leaning towards clinical implementation in gastrointestinal and head and neck cancers, closely followed by pulmonary, neuro, breast and gynaecological oncology. In cardiovascular and infectious disease, optical imaging is in a less advanced/proof of concept stage.

Conclusion

Targeted optical fluorescence imaging is rapidly evolving and expanding into the clinic, especially in the field of oncology. However, the imaging modality still has to overcome some major challenges before it can be part of the standard of care in the clinic, such as the provision of pivotal trial data. Intensive multidisciplinary (pre-)clinical joined forces are essential to overcome the delivery of such compelling phase III registration trial data and subsequent regulatory approval and reimbursement hurdles to advance clinical implementation of targeted optical fluorescence imaging as part of standard practice.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05504-y.

Evaluating the Feasibility and Efficacy of a Dual-Modality Nanoparticle Contrast Agent (Nanotrast-CF800) for Image-Guided Sentinel Lymph Node Mapping in the Oral Cavity of Healthy Dogs

A combination of pre and intraoperative sentinel lymph node (SLN) mapping techniques have been suggested to optimize SLN detection. A novel liposomal nanoparticle, Nanotrast-CF800 (CF800), utilizes computed tomography lymphography (CTL) and near infrared fluorescence imaging (NIRF) for image-guided surgery and SLN mapping. This novel tracer agent has not been evaluated in companion animals. The objective of this study was to evaluate the feasibility and efficacy of CF800 for SLN mapping in the oral cavity of healthy dogs and to report any local adverse effects. Six healthy adult purpose-bred research dogs randomly received either 1 mL (group 1) or 2 mL (group 2) of CF800 injected into the submucosa at the level of the right canine maxillary tooth. CTL and percutaneous NIRF were performed at 1, 3, and 10 min, then 1, 2, 4, 7, and 10 days post-injection (p.i). Overall, both CTL and NIRF identified SLNs in all dogs. The overall peak mean contrast enhancement of the SLNs was 73.98 HU (range 63.45-86.27 HU) at 2 days p.i. Peak fluorescence of the SLN occurred at 1 day p.i. The agent was retained within the SLN for at least 7 days for CTL and 4 days for percutaneous NIRF. No adverse effects were observed. Local administration of CF800 was simple and feasible for the detection of SLNs using CTL+NIRF in the head and neck of healthy dogs and was not associated with significant local adverse events.

Meta-analysis Comparing Fluorescence Imaging with Radioisotope and Blue Dye-Guided Sentinel Node Identification for Breast Cancer Surgery

INTRODUCTION

Conventional methods for axillary sentinel lymph node biopsy (SLNB) are fraught with complications such as allergic reactions, skin tattooing, radiation, and limitations on infrastructure. A novel technique has been developed for lymphatic mapping utilizing fluorescence imaging. This meta-analysis aims to compare the gold standard blue dye and radioisotope (BD-RI) technique with fluorescence-guided SLNB using indocyanine green (ICG).

METHODS

This study was registered with PROSPERO (CRD42019129224). The MEDLINE, EMBASE, Scopus, and Web of Science databases were searched using the Medical Subject Heading (MESH) terms 'Surgery' AND 'Lymph node' AND 'Near infrared fluorescence' AND 'Indocyanine green'. Studies containing raw data on the sentinel node identification rate in breast cancer surgery were included. A heterogeneity test (using Cochran's Q) determined the use of fixed- or random-effects models for pooled odds ratios (OR).

RESULTS

Overall, 1748 studies were screened, of which 10 met the inclusion criteria for meta-analysis. ICG was equivalent to radioisotope (RI) at sentinel node identification (OR 2.58, 95% confidence interval [CI] 0.35-19.08, p < 0.05) but superior to blue dye (BD) (OR 9.07, 95% CI 6.73-12.23, p < 0.05). Furthermore, ICG was superior to the gold standard BD-RI technique (OR 4.22, 95% CI 2.17-8.20, p < 0.001).

CONCLUSION

Fluorescence imaging for axillary sentinel node identification with ICG is equivalent to the single technique using RI, and superior to the dual technique (RI-BD) and single technique with BD. Hospitals using RI and/or BD could consider changing their practice to ICG given the comparable efficacy and improved safety profile, as well as the lesser burden on hospital infrastructure.

Comparison of two different surgical strategies for breast cancer patients treated with mastectomy plus sentinel lymph node biopsy

Two separated incisions are generally adopted in breast cancer patients treated by mastectomy plus sentinel lymph node biopsy (SLNB). However, one-incision procedure is also applied in clinical practice. The outcomes of the two different surgical strategies remain unknown. This issue needs to be investigated. The medical records of breast cancer patients who underwent a mastectomy combined with an SLNB were reviewed retrospectively. Group A comprised patients who received a single incision for both the mastectomy and SLNB. Group B comprised patients who received a second incision for the SLNB. Demographics and outcomes were compared between the two groups. There were 280 female patients divided into Groups A (n = 130) and B (n = 150) included in this study. Preoperatively, the two groups were similar in demographics for age, tumor size, tumor location, body mass index, pathologic type, and cancer stage (P > 0.05). Group A showed shorter surgical times (129.5 ± 29.0 vs. 136.7 ± 21.9 min), less postoperative upper limb numbness (12.3% vs. 25.3%), and more harvested sentinel lymph nodes (3.2 ± 1.1 vs. 2.7 ± 1.0) than Group B (P < 0.05). There were no significant differences for intraoperative blood loss, total postoperative drainage amount, hospital stay, upper limb motility, upper limb pain, upper limb edema, number of metastatic sentinel lymph nodes, follow-up time, or recurrent cases (P > 0.05). The one-incision approach for a breast cancer mastectomy plus SLNB has several advantages over the two-incision approach, including a shorter surgical time, decreased upper limb numbness, and the harvesting of more sentinel lymph nodes. Further prospective randomized controlled clinical trials should be designed to verify the current findings.

Predictive risk factors for sentinel lymph node metastasis using preoperative contrast-enhanced ultrasound in early-stage breast cancer patients

Background

Sentinel lymph node biopsy (SLNB) is the standard procedure for axillary staging in clinically node-negative (cN0) breast cancer patients. The positive rate of SLNs in cN0 stage patients ranges from 20.5% to 25.5%, so identifying appropriate candidates for SLNB is quite challenging. The aims of this study were to assess whether contrast-enhanced ultrasound (CEUS) could be utilized to noninvasively predict SLN metastasis, and to explore the predictive value of the involved factors.

Methods

Between May 2016 and May 2018, 217 consenting breast cancer patients undergoing SLNB were enrolled. Before the surgery, CEUS was utilized to identify the SLNs, and predict whether metastasis had occurred according to their enhancement pattern. Blue dye was also used to identify the SLNs during SLNB. The rates of identification and accuracy of both methods were recorded. The predictive outcomes of SLNs identified by CEUS were recorded and compared with the pathological diagnosis.

Results

Of the 217 cases, SLNs in 212 cases were successfully identified, comprising 208 cases identified by CEUS and 206 cases by blue dye, with no significant difference between the two methods (P=0.6470). A total of 78 cases were predicted SLN-positive preoperatively by CEUS, comprising 61 cases of SLN metastasis confirmed by pathology and 17 cases of no SLN metastasis, and 130 cases were predicted SLN-negative by CEUS, comprising 6 cases of SLN metastasis and 124 cases of no SLN metastasis. The sensitivity of CEUS preoperative prediction was 91.0%, the specificity was 87.9%, the positive and negative predictive values were 78.2% and 95.4%, respectively, and the accuracy was 88.9%. The maximum diameter size of positive SLNs predicted by CEUS was greater than that of negative SLNs (mean value 1.67±0.06 vs. 1.40±0.05 cm, P=0.0007). Similarly, the primary tumor size predicted SLN-positive by CEUS was greater than that in patients with negative SLNs (mean value 2.64±0.12 vs. 1.79±0.09 cm, P<0.0001).

Conclusions

CEUS accurately identified SLNs and can be used to noninvasively predict SLN metastasis in early-stage breast cancer patients. However, the primary tumor size and the SLN size should not be overlooked by clinicians when judging the status of SLNs. This novel method may be a recommended strategy for identifying appropriate SLNB candidates.

Determining agreement between preoperative computed tomography lymphography and indocyanine green near infrared fluorescence intraoperative imaging for sentinel lymph node mapping in dogs with oral tumours

Lymphatic drainage from the head and neck is variable with significant crossover, therefore sentinel lymph node (SLN) mapping can help ensure the appropriate lymph node(s) are sampled. To improve sensitivity, SLN mapping utilizing multiple modalities and a combination of preoperative computed tomography lymphography (CTL) and intraoperative near infrared fluorescence imaging (NIRF) with indocyanine green (ICG) +/- methylene blue (MB) dye has been suggested. The aim of this study was to describe a method for intraoperative ICG lymphography and determine agreement for SLN detection using preoperative CTL and intraoperative ICG NIRF + MB lymphography (IOL) in dogs with oral tumours. Fourteen client-owned dogs were included. All dogs had preoperative CTL with iodinated contrast and intraoperative IOL with an exoscope. Lymph nodes with CTL contrast-enhancement, blue staining or fluorescence were considered sentinel. The overall SLN identification rate was 100% when CTL and IOL were combined. A total of 57 SLNs were identified. Indocyanine green NIRF identified a greater proportion of SLNs (91%; 52/57) compared with MB (50.8%; 29/57) and CTL (42.1%; 24/57). Eighteen SLNs were identified by all three modalities with a fair level of agreement using Fleiss kappa. These findings suggest a combination of preoperative CTL with intraoperative SLN mapping techniques may greatly improve the ability to accurately detect the SLN in dogs with oral tumours.

A Pilot Study Evaluating the Effects of Magtrace® for Sentinel Node Biopsy in Breast Cancer Patients Regarding Care Process Optimization, Reimbursement, Surgical Time, and Patient Comfort Compared With Standard Technetium99

Background

Sentinel lymph node biopsy after technetium-99 (Tc⁹⁹) localization is a mainstay of oncologic breast surgery. The timing of Tc⁹⁹ injection can complicate operating room schedules, which can cause increasing overall costs of care and patient discomfort.

Methods

This study compared 59 patients who underwent breast cancer surgery including sentinel lymph node biopsy. Based on the surgeon’s choice, 29 patients were treated with Tc⁹⁹, and 30 patients received the iron-based tracer, Magtrace. The primary outcomes were time spent on the care pathway and operating time from commissioning of the probe to removal of the sentinel node. The secondary outcomes were patient pain levels and reimbursement.

Results

The mean time spent on the preoperative breast cancer care pathway was significantly shorter for the Magtrace group (5.4 ± 1.3 min) than for the Tc⁹⁹ group (82 ± 20 min) (p < 0.0001). The median time from probe usage to sentinel node extirpation was slightly but not significantly shorter in the Magtrace group (5 min; interquartile range [IQR], 3–15 min vs 10 min; IQR, 7–15 min; p = 0.151). Reimbursement and pain levels remained unchanged, and the hospital length of stay was similar in the two groups (Magtrace: 5.1 ± 2.3 days vs Tc⁹⁹: 4.5 ± 3.2 days).

Conclusions

Magtrace localization shortened the preoperative care pathway and did not affect surgical time or reimbursement. Once established, it could allow for cost reduction and improve patient comfort.

Sentinel lymph node detection by means of indocyanine green using the Karl Storz VITOM® fluorescence camera: a comparison between primary sentinel lymph node biopsy versus sentinel lymph node biopsy after neoadjuvant chemotherapy

PURPOSE

The usage of radioactive Technetium^99m (Tc^99m) colloid for the purpose of sentinel lymph node biopsy (SLNB) in early breast cancer is considered the gold standard in Germany. However, new tracers, such as near-infrared (NIR) imaging agents like indocyanine green (ICG) could offer an alternative in future, as they overcome drawbacks associated with radioactive Technetium^99m (Tc^99m) like limited availability, high costs and radioactivity exposure for both patients and surgeons.

METHODS

In this double-arm retrospective study, we sought to establish the usefulness of indocyanine green as an alternative or an addition to the conventional Technetium^99m (Tc^99m) in the identification of the SLN in early breast cancer.

RESULTS

Among the 161 patients who underwent primary SLNB, 34 patients had at least 1 SLN with metastasis. Among these patients with SLN metastasis, 33 had the SLN detected by ICG; while 31 had the SLN detected by Tc^99m. The conventional Technetium^99m radiotracer failed to detect 2 patients with metastasis in this Arm of the study. Among the 87 patients who underwent SLNB after NACT, 13 patients had at least 1 SLN with metastasis. Among these 13 patients with SLN metastasis, ICG and Tc^99m had detected the SLN among 12 patients, while 1 patient had been detected by ICG alone.

CONCLUSIONS

Our results show that ICG is as effective as the radioisotope for SLNB even among patients who have undergone NACT. This trial is registered with the German Clinical Trial Register, ID: DRKS00013606.

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.

Indocyanine Green Fluorescence Versus Blue Dye or Radioisotope Regarding Detection Rate of Sentinel Lymph Node Biopsy and Nodes Removed in Breast Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Either blue dye (BD) or radioisotope (RI) is mainly used for sentinel lymph node biopsy (SLNB) in breast cancer patients. Unlike the BD, RI has lower false-negative rate of SLNB. However, its lymphoscintigraphy, difficulty in preoperative injection, and undetected sentinel lymph nodes in some cases cause surgeons to rely only on BD. Currently, indocyanine green (ICG) fluorescence method (ICG-SLNB) is increasingly used as an alternative to the conventional mapping methods in many centers. This systematic review compared ICG with the conventional method of BD or RI in terms of detection rate of SLNB and the number of sentinel lymph nodes (SLNs) removed in.

METHODS

  We searched all relevant studies published between January 2000 and October 2019. All data on for evaluation of SLN detection rate, number of SLNs removed per patient, and tumor positive rate of SLNB were extracted.

RESULTS

A total of 30 studies, including 4,216 SLN procedures were retrieved. There was a statistically significant difference between ICG and BD method in terms of SLN detection rate (OR, 6.73; 95% CI, 4.20-10.78). However, there was no significant difference between ICG and RI in this regard (OR, 0.90; 95% CI, 0.40-2.03). The number of SLNs removed per patient were 2.35 (1.46-5.4), 1.92 (1.0-3.64), and 1.72 (1.35-2.08) for ICG, BD, and RI, respectively. Only in 8 studies, the tumor positive rates in SLNB could be analyzed (ICG, 8.5-20.7%; BD, 12.7-21.4%; RI, 11.3-16%).

CONCLUSION

ICG-SLNB could be an additional or an alternative method for axillary node mapping in breast cancer.<br />.

Can Low-cost Indo Cyanine Green Florescence Technique for Sentinel Lymph Node Biopsy Replace Dual Dye (Radio-colloid and Blue Dye) Technique in Early Breast Cancer: A Prospective Two-arm Comparative Study

BACKGROUND

The objective of this study was to assess the detection and accuracy of sentinel lymph node (SLN) biopsy (SLNB) using the low-cost indocyanine green (ICG) fluorescence method and to compare this method with the gold standard dual-dye method (radio-colloid + methylene blue dye [MB]).

MATERIALS AND METHODS

One hundred patients with node-negative early breast cancer assessed clinically and by ultrasound axilla underwent an SLNB procedure using technetium-99m radio-colloid, MB, and ICG. The detection rate of SLNs and positive SLNs and the number of SLNs were compared. The injection safety of ICG and MB was evaluated.

RESULTS

One hundred female patients with a median age of 52.3 years participated in the study. Sixty-eight percent had a body mass index < 25, 85% presented with a palpable lump, of which 59% were in the outer quadrant. SLNs were identified in all 100 cases. A total of 290 SLNs were removed (mean, 2.9; range, 1-6). The identification rate with dual dye was 94%, whereas with ICG alone, it was 96%. The SLNB sensitivity rate and false negative rate were 97.6% versus 93.2% and 3.1% versus 6.2% in the ICG and dual-dye combination, respectively. None of the patients had any local or systemic reaction with ICG; 3 patients with blue dye had tattooing and staining of skin.

CONCLUSION

ICG fluorescence imaging permits real time visualization of lymphatics and provides an additional dimension to SLN biopsy that is safe and effective. These results confirm high sensitivity for fluorescence localization with comparable performance to the gold standard. ICG can reliably replace dual dye and be employed as a sole tracer for SLNB in early breast cancer.

Use of indocyanine green fluorescence compared to radioisotope for sentinel lymph node biopsy in early-stage breast cancer: systematic review and meta-analysis

BACKGROUND

In early-stage breast cancer, indocyanine green (ICG)-fluorescence based sentinel lymph node (SLN) detection is being considered. This is a meta-analysis of SLN detection rates and sensitivity of ICG-fluorescence compared to radioisotope (RI), to evaluate its clinical applicability.

DATA SOURCES

Systematic review of full-text articles from PubMed and Scopus, of women with early breast cancer who underwent SLN mapping using ICG and RI concurrently was performed. The meta-analysis was performed using the Mantel-Haenszel method.

RESULTS

2301 patients from 19 studies were included. No significant difference was observed between ICG and RI for SLN detection (OR0.90,95%CI0.66-1.24) or sensitivity (OR1.23,95%CI0.73-2.05) with heterogeneity between studies (I² = 58%,P = 0.003). Sensitivity of dual mapping (ICG + RI) was significantly better compared to single mapping with RI (OR3.69,95%CI1.79-7.62) or ICG (OR3.32,95%CI1.52-7.24) alone with no heterogeneity between studies (I² = 0%,P = 0.004).

CONCLUSION

ICG-fluorescence could complement RI method or provide alternative in centers with poor accessibility to RI lymphoscintigraphy.

Real-Time Fluorescence Imaging in Thoracic Surgery

Near-infrared (NIR) fluorescence imaging provides a safe and cost-efficient method for immediate data acquisition and visualization of tissues, with technical advantages including minimal autofluorescence, reduced photon absorption, and low scattering in tissue. In this review, we introduce recent advances in NIR fluorescence imaging systems for thoracic surgery that improve the identification of vital tissues and facilitate the resection of tumorous tissues. When coupled with appropriate NIR fluorophores, NIR fluorescence imaging may transform current intraoperative thoracic surgery methods by enhancing the precision of surgical procedures and augmenting postoperative outcomes through improvements in diagnostic accuracy and reductions in the remission rate.

Near Infrared Fluorescent Lymph Node Mapping with Indocyanine Green in Breast Cancer Patients: A Prospective Trial

BACKGROUND

Near infrared (NIR) fluorescence imaging is an emerging modality that can enable real-time image-guided procedures. Indocyanine green (ICG) is an FDA-approved, inexpensive, and widely available NIR dye. We hypothesized that axillary lymphatic mapping with ICG is equivalent to lymphatic mapping with technetium 99m (^99mTc) in breast cancer patients.

STUDY DESIGN

Breast cancer patients (cT1-2, N0) were prospectively enrolled. Patients underwent lymphatic mapping with ^99mTc preoperatively and ICG mapping intraoperatively (0.8 mL). Sentinel lymph node (SLN) biopsy was guided by NIR camera and gamma probe. Rate of failed mapping, number of SLNs identified, and rate of identifying pathologically positive SLNs were compared between the 2 techniques (p < 0.05 was considered statistically significant).

RESULTS

Ninety-two female patients were enrolled (median age 59 years). Mean transit time from ICG injection in the breast to localization in the axilla was 5 minutes (range 2 to 29 minutes). No adverse reactions to ICG were noted. Mean number of SLNs identified with ICG and ^99mTc was 2.4 (SD 1.42) and 2.2 (SD 1.23), respectively (p = 0.34). Pathologically positive SLNs were identified in 18 (19.8%) patients. A total of 24 pathologically positive SLNs in 18 patients were identified by ICG in 24 of 24 (100%) patients and by ^99mTc in 23 of 24 (96%) patients (p = 0.99).

CONCLUSIONS

Indocyanine green with NIR fluorescence imaging can be safely and efficiently used for real-time intraoperative lymphatic mapping in breast cancer patients. Indocyanine green performs similarly to ^99mTc with regard to the number of SLNs identified, rate of failed mapping, and identification of pathologically positive SLNs.