Evaluation of sentinel node biopsy by combined fluorescent and dye method and lymph flow for breast cancer

Comparison of Indocyanine Green with conventional tracers for sentinel lymph node biopsy in breast cancer: A multidisciplinary evaluation of clinical effectiveness, safety, organizational and economic impact

BACKGROUND

Breast cancer is a global health problem, and sentinel lymph node biopsy (SLNB) is the standard procedure for early-stage breast cancer. Technetium-99 (TC-99), alone or combined with blue dye (BD) are conventional tracers for SLNB, but they have safety, availability, and cost limitations. Indocyanine green (ICG) is an alternative tracer that has been gaining acceptance among healthcare professionals. This study aimed at assessing the clinical and economic value of ICG in hospital settings, using the health technology assessment (HTA) framework.

METHODS

We conducted a comprehensive evaluation of ICG for SLNB, based on literature sources and data collected from two Italian hospitals that switched from TC-99 to ICG. We analyzed ICG's technical attributes through technology documentation and relevant databases. We performed a systematic literature review of 36 studies to assess the clinical effectiveness and safety of ICG. We obtained organizational insights from clinicians and the clinical engineer involved in the study. We applied Time-Driven Activity-Based Costing (TDABC) and Budget Impact Analysis (BIA) to estimate the economic impact of ICG. The ethical, legal, and social implications of ICG were considered through clinicians' inputs and technology documentation.

RESULTS

Our results showed that ICG had equivalent or superior clinical effectiveness compared to TC-99 and BD, with minimal adverse events. ICG simplified the surgical pathways, by streamlining procedures, reducing waiting times, and increasing flexibility in scheduling surgeries. Moreover, the TDABC analysis showed significant cost reductions by avoiding the need for pre-operative lymphoscintigraphy and hospitalization, with average savings per single care pathway of around 18% for ICG compared to TC-99. Finally, ICG improved patient experience, and proved regulatory compliance.

CONCLUSIONS

This study provided strong evidence for ICG's clinical and economic value for SLNB in breast cancer. It ascertained ICG as a valuable alternative to conventional tracers, ensuring clinical effectiveness along with economic and organizational benefits.

Augmenting Laparoscopic Surgery with Fluorescence Imaging

Minimally invasive endoscopic surgery is growing in veterinary medicine, in large part, due to the advantages associated with reduced pain, potential for decreased complications, and increased visualization of structures through magnification and illumination. With advancing technologies, we can now improve upon natural "white light" endoscopy with fluorescence-guided imaging. Near-infrared (NIR) cameras allow for real-time, high-definition visualization of vessels, anatomic structures, and perfusion. New uses of NIR technologies during laparoscopy are continuing to grow for vascular, lymphatic, and oncologic-related techniques. Limitations exist, and future efforts need to determine optimal dosing, tissue-specific fluorophores, and veterinary-specific techniques.

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.

Revolutionizing lymph node metastasis imaging: the role of drug delivery systems and future perspectives

The deployment of imaging examinations has evolved into a robust approach for the diagnosis of lymph node metastasis (LNM). The advancement of technology, coupled with the introduction of innovative imaging drugs, has led to the incorporation of an increasingly diverse array of imaging techniques into clinical practice. Nonetheless, conventional methods of administering imaging agents persist in presenting certain drawbacks and side effects. The employment of controlled drug delivery systems (DDSs) as a conduit for transporting imaging agents offers a promising solution to ameliorate these limitations intrinsic to metastatic lymph node (LN) imaging, thereby augmenting diagnostic precision. Within the scope of this review, we elucidate the historical context of LN imaging and encapsulate the frequently employed DDSs in conjunction with a variety of imaging techniques, specifically for metastatic LN imaging. Moreover, we engage in a discourse on the conceptualization and practical application of fusing diagnosis and treatment by employing DDSs. Finally, we venture into prospective applications of DDSs in the realm of LNM imaging and share our perspective on the potential trajectory of DDS development.

Determining Accurate Dye Combinations for Sentinel Lymph Node Detection: A Systematic Review

Background

Lymphatic dyes are commonly used to map the drainage path from tumor to lymphatics, which are biopsied to determine if spread has occurred. A blue dye in combination with technetium-99 is considered the gold standard for mapping, although many other dyes and dye combinations are used. Not all of these substances have the same detection efficacy.

Methods

A systematic review of PubMed, SCOPUS, Web of Science, and Medline was performed. The predefined search terms were (indocyanine green OR isosulfan blue OR lymphazurin OR patent blue OR methylene blue OR fluorescein OR technetium-99) AND combination AND dye AND (sentinel lymph node biopsy OR lymphedema OR lymphatics OR lymph OR microsurgery OR cancer OR tumor OR melanoma OR carcinoma OR sarcoma).

Results

The initial search returned 4267 articles. From these studies, 37 were selected as candidates that met inclusion criteria. After a full-text review, 34 studies were selected for inclusion. Eighty-nine methods of sentinel lymph node (SLN) detection were trialed using 22 unique dyes, dye combinations, or other tracers. In total, 12,157 SLNs of 12,801 SLNs were identified. Dye accuracy ranged from 100% to 69.8% detection. Five dye combinations had 100% accuracy. Dye combinations were more accurate than single dyes.

Conclusions

Combining lymphatic dyes improves SLN detection results. Replacing technetium-99 with ICG may allow for increased access to SLN procedures with comparable results. The ideal SLN tracer is a low-cost molecule with a high affinity for lymphatic vessels due to size and chemical composition, visualization without specialized equipment, and no adverse effects.

[Fluorescence lymphography for sentinal lymph node biopsy in breast cancer]

OBJECTIVE

To study diagnostic value of fluorescence lymphography for sentinel lymph node biopsy in breast cancer.

MATERIAL AND METHODS

The study enrolled 25 patients with breast cancer T1-2N0-1M0 between March 2023 and July 2023. Eight ones underwent neoadjuvant chemotherapy. In 3 patients, morphologically verified metastases cN1 in axillary lymph nodes regressed after treatment. After sentinel lymph node biopsy, all patients underwent standard axillary lymphadenectomy. Subareolar injection of indocyanine green 1 ml (5 mg/ml) was performed immediately before surgery. Fluorescence imaging was performed using the MARS system.

RESULTS

Detection rate was 100%. Mean number of sentinel lymph nodes was 2. Metastatic lesions of sentinel lymph nodes were observed in 6 patients (24%) with micro-metastases in 2 cases. In 50% of cases, metastatic lesion did not extend beyond sentinel lymph nodes. False negative result was obtained in 1 (4%) patient. Mean number of metastases was 1.8 (max 3 in one patient).

CONCLUSION

Sentinel lymph node biopsy with fluorescence lymphography is a sensitive method. The advantages of this technique are visualization of subcutaneous lymphatic vessels and skin incision for access to sentinel lymph nodes, as well as visualization of sentinel lymph nodes after skin incision.

A Novel Injection Protocol Using Voluven®-Assisted Indocyanine Green with Improved Near-Infrared Fluorescence Guidance in Breast Cancer Sentinel Lymph Node Mapping-A Translational Study

BACKGROUND

Near-infrared (NIR) fluorescence-guided surgery with indocyanine green (ICG) has been demonstrated to provide high sensitivity in sentinel lymph node biopsy (SLNB) for breast cancer but has several limitations, such as unstable pharmacokinetics, limited fluorescence brightness, and undesired diffusion to neighboring tissues. This paper investigates the use of Voluven® as the solvent for ICG fluorescence-guided SLNB (ICG-SLNB).

METHODS

The photophysical properties of ICG in water and Voluven® were evaluated in laboratory experiments and in a mouse model. Nine patients with early breast cancer underwent subareolar injection of diluted ICG (0.25 mg/ml) for ICG-SLNB. Six of the nine patients received ICG dissolved in Voluven® (ICG:Voluven®), while three were administered ICG dissolved in water (ICG:water); a repetitive injection-observation protocol was followed for all patients. The mapping image quality was evaluated.

RESULTS

Laboratory experiments and in vivo mouse study showed improved fluorescence and better targeting using Voluven® as the solvent. ICG-SLNB with a repetitive injection-observation protocol was successfully performed in all nine patients. ICG:Voluven® administration had an overall better signal-to-background ratio (SBR) in sequential sentinel lymph nodes. The rates of transportation within the lymphatics were also improved using ICG:Voluven® compared with ICG:water.

CONCLUSIONS

From basic research to animal models to in-human trial, our study proposes a repetitive injection-observation technique with ICG:Voluven®, which is characterized by better transportation and more stable mapping quality for ICG-SLNB in breast cancer patients.

Efficacy of indocyanine green fluorescence for the identification of non-palpable breast tumours: systematic review

BACKGROUND

Accurate tumour localization is crucial for precise surgical targeting and complete tumour removal. Indocyanine green fluorescence, an increasingly used technique in oncological surgery, has shown promise in localizing non-palpable breast tumours. The aim of this systematic review was to describe the efficacy of indocyanine green fluorescence for the identification of non-palpable breast tumours.

METHODS

A systematic literature search was performed in PubMed, Embase, and the Cochrane Library, including studies from 2012 to 2023. Studies reporting the proportion of breast tumours identified using indocyanine green fluorescence were included. The quality of the studies and their risk of bias were appraised using the Methodological Index for Non-Randomized Studies ('MINORS') tool. The following outcomes were collected: identification rate, clear resection margins, specimen volume, operative time, re-operation rate, adverse events, and complications.

RESULTS

In total, 2061 articles were screened for eligibility, resulting in 11 studies, with 366 patients included: two RCTs, three non-randomized comparative studies, four single-arm studies, and two case reports. All studies achieved a 100 per cent tumour identification rate with indocyanine green fluorescence, except for one study, with an identification rate of 87 per cent (13/15). Clear resection margins were found in 88-100 per cent of all patients. Reoperation rates ranged from 0.0 to 5.4 per cent and no complications or adverse events related to indocyanine green occurred.

CONCLUSION

Indocyanine green fluorescence has substantial theoretical advantages compared with current routine localization methods. Although a limited number of studies were available, the current literature suggests that indocyanine green fluorescence is a useful, accurate, and safe technique for the intraoperative localization of non-palpable breast tumours, with equivalent efficacy compared with other localization techniques, potentially reducing tumour-positive margins.

The effect of immediate lymphatic reconstruction on the post-operative drain output after axillary lymph node dissection for breast cancer: A retrospective comparative study

INTRODUCTION

Axillary lymph node dissection (ALND) for breast cancer has been considered to be associated with a variety of complications, such as excessive postoperative wound drainage, prolonged drain placement, or seroma formation in the short term, or arm lymphedema in the long run. Immediate lymphedema reconstruction (ILR) has been proposed to reduce the occurrence of arm lymphedema by anastomosing the transected arm lymphatics to nearby branches of the axillary vein immediately after ALND. This study aims to demonstrate that ILR can also reduce the postoperative drainage amount.

PATIENTS AND METHODS

Between April 2020 and January 2022, a total of 76 breast cancer patients receiving ALND were reviewed. Forty four of them also received ILR immediately after ALND. The assignment of ILR surgery was non-random, based on patients' willingness and plastic surgeons' availability. The lymphatic vessels in the axillary wound were anastomosed with nearby terminal branches of the axillary vein under surgical microscope. Patients' characteristics, including age, body mass index (BMI), neoadjuvant therapy, type of breast surgery, the occurrence of seroma formation, number of removed lymph nodes, number of positive nodes, and the drainage amount from the operative wounds were compared between ILR and non-ILR groups.

RESULTS

No statistically significant difference was noted between groups in terms of age (56.5 ± 9.8 vs. 60.9 ± 10.7, p = .09), BMI (22.6 ± 3.7 vs. 23.7 ± 3.8, p = .27), type of breast surgery (p = .32), the occurrence of seroma formation (p = 1.0), the likelihood of receiving neoadjuvant therapy (p = .12), number of lymph nodes removed (17.5 ± 7.6 vs. 17.4 ± 8.3, p = .96), or number of positive nodes on final pathology (3.7 ± 5.4 vs. 4.8 ± 8.5, p = .53) except the ILR group had statistically significantly less drainage amount than non-ILR group (39.3 ± 2.6 vs. 48.3 ± 3.7, p = .046).

CONCLUSION

For breast cancer patients receiving ALND, the immediate lymphatic reconstruction can reduce the postoperative drainage amount from the operative wound.

The Usefulness of a Three-Microneedle Device for Indocyanine Green Fluorescence Lymphography

Background: Indocyanine green (ICG) fluorescence lymphography is widely used to diagnose lymphedema. There is little consensus on the appropriate injection method for ICG fluorescence lymphangiography. We used a three-microneedle device (TMD) for skin injection of ICG solution and investigated its usefulness. Methods and Results: Thirty healthy volunteers were injected with ICG solution using a 27-gauge (27G) needle in one foot and a TMD in the other foot. Injection-related pain was evaluated using the Numerical Rating Scale (NRS) and Face Rating Scale (FRS). The skin depth of the injected ICG solution was evaluated by injecting the solution into the skin of amputated lower limbs using a 27G needle or TMD using ICG fluorescence microscopy. The median and interquartile range of the NRS scores was 3 (3-4) and 2 (2-4) in the 27G needle and TMD groups, respectively; that of the FRS scores was 2 (2-3) and 2 (1-2) in the 27G needle and TMD groups, respectively. Injection-related pain was significantly lower with the TMD than with the 27G needle. The lymphatic vessels were similarly visible using both needles. The depth of the ICG solution varied for each injection with a 27G needle (400-1200 μm) and was consistent at ∼300-700 μm below the skin surface using the TMD. Injection depth was significantly different between the 27G needle and the TMD. Conclusions: Injection-related pain decreased using the TMD, and ICG solution depth was consistent on fluorescence lymphography. A TMD may be useful for ICG fluorescence lymphography. Clinical Trials Registry (UMIN-CTR; ID: UMIN000033425).

Role of Nuclear Sentinel Lymph Node Mapping Compared to New Alternative Imaging Methods

With the emergence of sentinel node technology, many patients can be staged histopathologically using lymphatic mapping and selective lymphadenectomy. Structural imaging by using US, CT and MR permits precise measurement of lymph node volume, which is strongly associated with neoplastic involvement. Sentinel lymph node detection has been an ideal field of application for nuclear medicine because anatomical data fails to represent the close connections between the lymphatic system and regional lymph nodes, or, more specifically, to identify the first draining lymph node. Hybrid imaging has demonstrated higher accuracy than standard imaging in SLN visualization on images, but it did not change in terms of surgical detection. New alternatives without ionizing radiations are emerging now from "non-radiological" fields, such as ophthalmology and dermatology, where fluorescence or opto-acoustic imaging, for example, are widely used. In this paper, we will analyze the advantages and limits of the main innovative methods in sentinel lymph node detection, including innovations in lymphoscintigraphy techniques that persist as the gold standard to date.

Indocyanine Green Is a Safe and Effective Alternative to Radioisotope in Breast Cancer Sentinel Lymph Node Biopsy regardless of Patient Body Mass Index

INTRODUCTION

A recent meta-analysis [Lancet Oncol. 2010;11:908-909] has confirmed high sensitivity of indocyanine green (ICG) fluorescence mapping for sentinel node detection in early breast cancer. Concerns have previously been raised regarding the efficacy in patients with high body mass index (BMI).

MATERIALS AND METHODS

All consecutive patients undergoing sentinel lymph node biopsies (SLNBs) for early breast cancer in NHS Tayside were included in a prospective audit of surgical and pathology findings. All patients included in the study received dual injection of patent blue dye and ICG. Approval was obtained from the local Caldicott guardian for collection and use of personal data.

RESULTS

Of 239 cases, all were female patients of mean age 62 years (range 27-93). In 4.2% (10/239) of cases, neither blue dye nor ICG was present in the axilla. Of the remaining 229 SLNB cases in this series, surgeons documented retrieval of 451 nodes, with a mean surgical nodal count per case of 1.97 (range 1-5) and pathological nodal count of 2.15 (range 0-7). Eighty three cases were performed in patients with BMI 30-39.9 and 21 cases with BMI ≥40, with nodal detection rates of 96.4% (80/83) and 95.2% (20/21), respectively, in these groups of patients. Twenty percent (48/229) of cases had nodal metastases on histopathology.

CONCLUSIONS

This is a large single-center study which demonstrates the safety and accuracy of the combined ICG and blue dye technique for SLNB in breast cancer. This is represented by nodal detection rates and node positivity rates which are comparable to previous multicenter studies of standard SLNB regardless of BMI.

Raman Nanotags-Guided Intraoperative Sentinel Lymph Nodes Precise Location with Minimal Invasion

The accurate positioning of sentinel lymph node (SLN) by tracers during surgery is an important prerequisite for SLN biopsy. A major problem of traditional tracers in SLN biopsy is the short surgery window due to the fast diffusion of tracers through the lymphatics, resulting in a misjudgment between SLN and second echelon lymph node (2nd LN). Here, a nontoxic Raman nanoparticle tracer, termed gap-enhanced Raman tags (GERTs), for the accurate intraoperative positioning of SLNs with a sufficient surgical time window is designed. In white New Zealand rabbit models, GERTs enable precise identification of SLNs within 10 min, as well as provide the surgeon with a more than 4 h time window to differentiate SLN and 2nd LN. In addition, the ultrahigh sensitivity of GERTs (detection limit is 0.5 × 10-12 m) allows detection of labeled SLNs before surgery, thereby providing preoperative positioning information for minimally invasive surgery. Comprehensive biosafety evaluations carried out in the context of the Food and Drug Administration and International Standard Organization demonstrate no significant toxicity of GERTs, which supports a promising clinical translation opportunity of GERTs for precise SLN identification in breast cancer.

Clinical application of indocyanine green fluorescence imaging in laparoscopic lymph node dissection for intrahepatic cholangiocarcinoma: A pilot study (with video)

BACKGROUND

Intrahepatic cholangiocarcinoma is a highly lethal malignancy characterized by lymph node metastasis. This study aimed to evaluate the efficacy of indocyanine green fluorescence for visualization of lymphatic drainage and to assess its clinical application during laparoscopic lymph node dissection for intrahepatic cholangiocarcinoma.

METHODS

All patients with intrahepatic cholangiocarcinoma who underwent laparoscopic left hepatectomy and lymph node dissection between October 2018 and January 2021 were reviewed. The patients were assigned to the indocyanine green group or non-intrahepatic cholangiocarcinoma group based on the staining technique used.

RESULTS

Of 38 patients with left hemiliver intrahepatic cholangiocarcinoma, 20 underwent intrahepatic cholangiocarcinoma tracer-guided laparoscopic radical left hepatectomy; 12 procedures were successful (indocyanine green group). During the same period, 18 patients were treated with traditional laparoscopic resection (control group). Their intraoperative factors were comparable and there were no differences in the incidence or severity of their postoperative complications 30 days after surgery (P > .05). In the indocyanine green group, more lymph nodes were harvested (mean [range]: 7.0 [6.0-8.0] vs 3.5 [3.0-5.0], P < .001) and the proportion of confirmed pathologic lymph nodes was higher (75.0%, 66.7%-87.5% vs 40%, 33.3%-50.0%, P < .001). ICG staining was observed in all (12/12, 100%) patients in the intrahepatic cholangiocarcinoma group at stations 8 and 12, and 9 (9/12, 75%) and 10 (11/12, 91.7%) patients at Stations 13 and 7, respectively.

CONCLUSION

The indocyanine green fluorescence imaging system is feasible, safe, and effective for tracing lymph nodes. It can be used to identify regional lymphatic drainage patterns and help define the scope of lymph node dissection in patients with intrahepatic cholangiocarcinoma.

Real-Time In Situ Navigation System With Indocyanine Green Fluorescence for Sentinel Lymph Node Biopsy in Patients With Breast Cancer

BACKGROUND

The naked-eye invisibility of indocyanine green fluorescence limits the application of near-infrared fluorescence imaging (NIR) systems for real-time navigation during sentinel lymph node biopsy (SLNB) in patients with breast cancer undergoing surgery. This study aims to evaluate the effectiveness and safety of a novel NIR system in visualizing indocyanine green fluorescence images in the surgical field and the application value of combined methylene blue (MB) and the novel NIR system in SLNB.

METHODS

Sixty patients with clinical node-negative breast cancer received indocyanine green (ICG) and MB as tracers. Two NIR system instruments, namely, lymphatic fluorescence imaging system (LFIS) designed by the University of Science and Technology of China and vascular imager by Langfang Mingde Medical Biotechnology Co., Ltd. (Langfang vascular imager), were used as navigation assistance to locate sentinel lymph nodes (SLNs). Excising the lymph nodes developed by both MB and ICG by two NIR systems or palpably suspicious as SLNs and undergoing rapid pathological examination.

RESULTS

Both instruments exhibited 95% (57/60) success for real-time lymphatic fluorescent images. A total of 186 SLNs were identified, of which two were pathologically confirmed as lacking any lymph node tissue. SLN identification rate was 100% (184/184) for MB plus LFIS and 86.96% (160/184) for MB alone. The median number of SLNs identified by LFIS combined with MB was 3 (range of 1-8), which was significantly higher than that by MB alone at 2 (range 1-7) (P<0.05).

CONCLUSION

LFIS effectively detects SLNs in breast cancer, projects the fluorescence signals during surgery, and provides a continuous surgical navigation system without the need for a remote monitor. The ICG method navigated by combined LFIS and MB may be a promising alternative tracer for radioisotope in SLN mapping.

CLINICAL TRIAL REGISTRATION

This clinical trial was registered with the China Clinical Trial Center, registration number ChiCTR2000039542.

Near-infrared laparoscopy with indocyanine green for axillary sentinel lymph node biopsy in early breast cancer: preliminary experience of a single unit

Background

A sentinel lymph node biopsy (SLNB) is a routine procedure for axillary staging in cN0 breast cancer (BC) patients. Indocyanine green (ICG) fluorescence can detect sentinel lymph nodes with higher sensitivity than carbon nanoparticle suspension (CNS). The present study investigated the availability and benefits of a near-infrared (NIR) laparoscopy-assisted SLNB using ICG and carbon nanoparticle suspension as tracers.

Methods

Forty patients with invasive BC, who had clinically negative axillary lymph nodes, participated in this observational study. ICG and CNS tracers were injected into the periareolar region simultaneously or sequentially. In the endoscopy-assisted group (n=20), the patients were given NIR laparoscopic SLNB based on ICG fluorescence and CNS staining. In the open-surgery group, the patients were given traditional SLNB using an open incision, and CNS tracers were injected into the same region as that in the endoscopy-assisted group.

Results

In the endoscopy-assisted group, lymphatic vessels and sentinel lymph nodes (SLNs) were successfully identified using ICG fluorescence imaging in most patients (19/20). The average number of SLNs removed was 2.85 (range, 1-4) in the endoscopy-assisted group, and 3.40 (range, 1-7) in the open-surgery group. There was no significant difference between the number of detected nodes (P=0.30). The patients who underwent endoscopy-assisted SLNBs had similar operating times, blood loss and hospital-stay lengths, but lower postoperative drainage volumes and higher satisfaction scores, as they did not have axillary incisions.

Conclusions

The NIR laparoscopy-assisted ICG-guided technique is a feasible and surgeon-friendly method for SLNB with good efficacy and acceptable safety. When combined with CNS, more SLNs can be detected and dissected.

Contemporary update of SPECT tracers and novelties in radioguided surgery: a perspective based on urology

Recent technical advances and implementation of novel radiotracers have further increased the potential of radioguided surgery for a broad variety of malignancies. Indeed, the possibilities for future applications of novel radiotracers in diverse oncological strategies has become more promising than ever. This literature review aims to provide a contemporary update on a selected group of radiotracers and evaluates the usability of radioguided surgery and sentinel node procedures, focusing on most promising advances. For example, the impact of targeted radiotracers on prostate specific membrane antigen (PSMA), CD206 receptor-targeted agents (^99mTc-tilmanocept), and hybrid tracers adding fluorescence to radioguidance (ICG-^99mTc-nanocolloid) as well as targeting hypoxia-induced carbonic anhydrase IX (CAIX) will be covered. Furthermore, future outlooks on the implementation of gold nanoparticles (AuNP's), but also technical advances in improved radiotracer detection by hybrid gamma devices will be discussed.

Long-term follow-up results of fluorescence and blue dye guided sentinel lymph node biopsy in early breast cancer

PURPOSE

This study aimed to assess the efficacy of the combination of indocyanine green (ICG) and methylene blue (MB) dye in early breast cancer patients undergoing sentinel lymph node biopsy (SLNB).

METHODS

Between January 2011 and December 2015, 1061 early breast cancer patients underwent SLNB were included. SLNB was performed for enrolled patients by injection of both ICG and MB. Detection rate, positivity, and number of sentinel lymph nodes (SLNs) by ICG and MB were analysed. Axillary recurrence and arm lymphedema at 5.6-year follow-up were reported.

RESULTS

The combination of ICG and MB resulted in a very high detection rate of 99.6%, the median number of sentinel lymph nodes was 3. A total of 374 histologically confirmed positive SLNs were detected in 237 patients, 96.6% of the positive patients and 94.1% of the positive nodes could be identified by the combination of ICG and MB. After a median follow-up of 5.6 (2-9.3) years, 0.64% of patients with negative SLNs had ipsilateral axillary recurrence, and the incidence of arm lymphedema was 2.1%.

CONCLUSIONS

Although the missing isotope control weakens the interpretation of the findings, the dual tracing modality of ICG and MB, without involvement of radioactive isotopes, was an effective method for SLNB in patients with early breast cancer.

TRIAL REGISTRATION

ACTRN12612000109808. Registered on 23 January 2012.

Comparisons of ICG-fluorescence with conventional tracers in sentinel lymph node biopsy for patients with early-stage breast cancer: A meta-analysis

Radioisotopes (RI) and blue dye (BD) are routinely used markers for staining during sentinel lymph node biopsy (SLNB) in breast cancer. Compared with traditional tracers, tracer performance of indocyanine green (ICG) has been controversial. A total of 21 studies were selected from the PubMed, EMBASE and Cochrane Library databases. Detection ability was judged based on four endpoints: i) The identification rate (IR) of the patients; ii) the IR of the sentinel lymph nodes (SLNs); iii) the IR of the positive SLNs; and iv) the false negative rate (FNR). Compared with BD, ICG was superior in terms of the IR of the patients [odds ratio (OR)=7.17; 95% CI, 3.98-12.94), the IR of the SLNs (OR=8.84; 95% CI, 6.71-11.66) and FNR (OR=0.20; 95% CI, 0.08-0.48) using a fixed-effects model. There was a significant difference in both the IR of the positive SLNs (OR=21.32; 95% CI, 2.84-160.14) and FNR (OR=0.46; 95% CI, 0.23-0.91) in the ICG vs. RI group. Furthermore, when using ICG at the recommended dose, a significant difference was found in the IR of the patients (OR=1.77; 95% CI, 1.09-2.85) and the IR of the SLNs (OR=21.62; 95% CI, 5.23-89.43) using a fixed-effects model. In the ICG vs. BD combined with RI group, there were no differences in either the IR of the patients (OR=5.10; 95% CI, 0.24-107.48) or the IR of SLNs (OR=5.10; 95% CI, 0.60-256.66). In conclusion, ICG was a better tracer compared with BD or RI alone and was not a worse tracer compared with BD combined with RI. The use of the recommended dose of ICG had an improved tracer effect. ICG is expected to be widely used in SLNB in view of its clinical advantages.

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.

Indocyanine green fluorescence method for sentinel lymph node biopsy in breast cancer

BACKGROUND/OBJECTIVE

Breast biopsy and analysis of sentinel lymph nodes (SLNs) accurately predict tumor status in the affected basin and help in avoiding unnecessary axillary lymph node dissection, which is associated with remarkable morbidity risk. Blue dye and radioisotope are the most widely used mapping agents, but non-radioactive tracers of comparable accuracy warrant further investigation. This study aimed to investigate utilization of indocyanine green (ICG) fluorescence in sentinel node localization compared with blue dye and to assess the incremental value of ICG.

METHODS

A total of 39 consecutive patients underwent sentinel lymph node biopsy (SLNB) (40 cases: 38 unilateral and 1 bilateral) with combined blue dye and ICG for localization. The obtained fluorescence images of the lymphatic system were investigated.

RESULTS

All 84 lymph nodes removed in 40 procedures were identified by ICG, but only 37 were identified by blue dye. The ICG method identified an average of 2.1 SLNs in 39 of 40 cases with a detection rate of 97.5%, but only 0.93 SLN per case with blue dye. Subcutaneous lymphatic channel patterns were also detected by fluorescent imaging in 37 procedures, which all revealed lymphatic drainage toward the axilla except in one case with internal mammary pathway.

CONCLUSION

This study demonstrated the accuracy and safety of ICG for SLNB and its superiority to blue dye method in SLN localization. Therefore, ICG fluorescence method is safe and effective addition in breast clinical settings, wherein blue dye alone is used.

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.

Preliminary study of contrast-enhanced ultrasound in combination with blue dye vs. indocyanine green fluorescence, in combination with blue dye for sentinel lymph node biopsy in breast cancer

Background

This preliminary study aimed to examine the feasibility of sentinel lymph node biopsy (SLNB) using contrast-enhanced ultrasound (CEUS) vs. indocyanine green fluorescence (ICG), combined with blue dye in patients with breast cancer.

Methods

This was a retrospective study of consecutive female patients with invasive stage I-III (based on pre-operative physical examination and imaging) primary breast cancer at the Peking Union Medical College Hospital between 01/2013 and 01/2015 who underwent preoperative SLNB by ICG + blue dye or CEUS + blue dye. The numbers of detected SLNs, detection rates, and recurrence-free survival (RFS) rates were compared between the two groups.

Results

A total of 443 patients were included. The detection rates of SLNs in the CEUS + blue dye and ICG + blue dye groups were 98.4 and 98.1%, respectively (P = 0.814). The average numbers of SLNs detected per patient showed no significant difference between the two groups (3.06 ± 1.33 and 3.12 ± 1.31 in the CEUS + blue dye and ICG + blue dye groups, respectively; P = 0.659). After a median follow-up of 46 months, five patients in the CEUS + blue dye group and 15 in the ICG + blue dye group had recurrence. RFS rates showed no significant difference (P = 0.55).

Conclusion

This preliminary study suggests that CEUS + blue dye and ICG + blue dye are both feasible for SLN detection in breast cancer.

Factors that affect the false negative rate of sentinel lymph node mapping with methylene blue dye alone in breast cancer

Objective

This study aimed to investigate the clinicopathological factors of the false negative rate (FNR) and accuracy of sentinel lymph node biopsy (SLNB) mapping with 1% methylene blue dye (MBD) alone, and to examine how to reduce the FNR in patients with breast cancer.

Methods

A total of 365 patients with invasive breast carcinoma who received axillary lymph node dissection after SLNB were retrospectively analyzed. SLNB was performed with 2 to 5 mL of 1% MBD. We studied the clinicopathological factors that could affect the FNR of SLNB.

Results

The identification rate of sentinel lymph nodes (SLNs) was 98.3% (359/365) and the FNR of SLNB was 10.4% (16/154). Multivariate analysis showed that the number of dissected SLNs and metastatic lymph nodes were independent predictive factors for the FNR of SLNB. The FNR in patients with 1, 2, 3, and ≥4 SLNs was 23.53%, 15.79%, 3.85%, and 1.79%, respectively.

Conclusions

SLNB mapping with MBD alone in patients with breast cancer can produce favorable identification rates. The FNR of SLNB decreases as the number of SLNs rises. Because of side effects of searching for additional SLNs and the FNR, removal of three or four SLNs may be appropriate.

Application of indocyanine green-enhanced near-infrared fluorescence-guided imaging in laparoscopic lateral pelvic lymph node dissection for middle-low rectal cancer

BACKGROUND

As one effective treatment for lateral pelvic lymph node (LPLN) metastasis (LPNM), laparoscopic LPLN dissection (LPND) is limited due to the complicated anatomy of the pelvic sidewall and various complications after surgery. With regard to improving the accuracy and completeness of LPND as well as safety, we tried an innovative method using indocyanine green (ICG) visualized with a near-infrared (NIR) camera system to guide the detection of LPLNs in patients with middle-low rectal cancer.

AIM

To investigate whether ICG-enhanced NIR fluorescence-guided imaging is a better technique for LPND in patients with rectal cancer.

METHODS

A total of 42 middle-low rectal cancer patients with clinical LPNM who underwent total mesorectal excision (TME) and LPND between October 2017 and March 2019 at our institution were assessed and divided into an ICG group and a non-ICG group. Clinical characteristics, operative outcomes, pathological outcomes, and postoperative complication information were compared and analysed between the two groups.

RESULTS

Compared to the non-ICG group, the ICG group had significantly lower intraoperative blood loss (55.8 ± 37.5 mL vs 108.0 ± 52.7 mL, P = 0.003) and a significantly larger number of LPLNs harvested (11.5 ± 5.9 vs 7.1 ± 4.8, P = 0.017). The LPLNs of two patients in the non-IVG group were residual during LPND. In addition, no significant difference was found in terms of LPND, LPNM, operative time, conversion to laparotomy, preoperative complication, or hospital stay (P > 0.05).

CONCLUSION

ICG-enhanced NIR fluorescence-guided imaging could be a feasible and convenient technique to guide LPND because it could bring specific advantages regarding the accuracy and completeness of surgery as well as safety.

Randomized comparison between indocyanine green fluorescence plus 99mtechnetium and 99mtechnetium alone methods for sentinel lymph node biopsy in breast cancer

Use of both patent blue and a radioisotope to locate, and reduce the risk of sentinel lymph node (SLN) detection failure in breast cancer is recommended, but drawbacks commonly lead to using only a radioisotope. An alternative method would therefore be valuable. This randomized, controlled study in 99 patients compared SLN detection using ^99mtechnetium (Tc) alone versus Tc combined with indocyanine green (ICG). The primary endpoint was the SLN identification rate. The primary outcome measure was the number of patients with <2 SLN detected. One SLN was detected in 44.0% of patients in the dual detection group and 40.8% in the ^99mTc alone group (RR = 1.08 (95% CI 0.68; 1.72), p = 0.84). A mean (±SD) of 2.14 ± 1.23 SLN were identified in the dual detection group vs. 1.77 ± 0.85 using Tc alone (p = 0.09). Eight-five (78.7%) SLN were both ICG+ and TC+, 15 (13.9%) ICG+ and Tc−, and 7 (6.5%) ICG− and Tc+. SLN detected were ICG-positive in 92.6% of patients and ^99mTc-positive in 85.2% with. No adverse event related to ICG injection was recorded. Dual detection of SLN using ICG and radioisotope is reliable and sensitive but was not superior to isotope alone in successfully locating SLN in our pilot randomized trial.

Analysis of Postoperative Complications After 303 Sentinel Lymph Node Identification Procedures Using the SentiMag® Method in Breast Cancer Patients

Background

The objective of this paper was to assess the complications following sentinel lymph node biopsy (SLNB) in breast cancer patients using the SentiMag® method.

Material/Methods

The study material consisted of 368 patients who had received the SLNB procedure in combination with wide local excision (WLE), simple mastectomy or who had an autonomous SLNB procedure in the period from January 2014 to September 2017. The final study group consisted of 303 patients who attended follow-up consultations.

Results

Sensory disturbances in the arm occurred in 12 patients (9.9%), including 3 patients (1.5%) after WLE and 9 patients (8.4%) after simple mastectomy. Restricted mobility in the upper limb was experienced by 9 patients (7.1%), including 3 patients (1.5%) after WLE and 6 patients (5.6%) after simple mastectomy. Minimal-degree lymphedema developed in 9 patients (7.5%), including 2 patients (1%) after WLE and 7 patients (6.5%) after simple mastectomy. A significant correlation was demonstrated between the incidence of these complications and the number of lymph nodes dissected. A significantly higher incidence of paresthesia and lymphedema was revealed for simple mastectomy with SLNB when compared to WLE with SLNB. Discolorations upon tracer administration were observed in 47 patients (15.5%).

Conclusions

SentiMag^® is a safe sentinel lymph node identification method used in breast cancer and has a low risk of complications. The rate of complications increases together with the number of dissected lymph nodes and the extent of the surgery. The possibility of temporary discolorations on the skin should be communicated to the patients explicitly prior to surgery.

Detection of Sentinel Lymph Nodes with Near-Infrared Imaging in Malignancies

Optical molecular imaging, a highly sensitive and noninvasive technique which is simple to operate, inexpensive, and has the real-time capability, is increasingly being used in the diagnosis and treatment of carcinomas. The near-infrared fluorescence dye indocyanine green (ICG) is widely used in optical imaging for the dynamic detection of sentinel lymph nodes (SLNs) in real time improving the detection rate and accuracy. ICG has the advantages of low scattering in tissue absorbance, low auto-fluorescence, and high signal-to-background ratio. The detection rate of axillary sentinel lymph nodes biopsy (SLNB) in breast cancers with ICG was more than 95 %, the false-negative rate was lower than 10 %, and the average detected number ranged from 1.75 to 3.8. The combined use of ICG with nuclein or blue dye resulted in a lower false-negative rate. ICG is also being used for the sentinel node detection in other malignant cancers such as head and neck, gastrointestinal, and gynecological carcinomas. In this article, we provide an overview of numerous studies that used the near-infrared fluorescence imaging to detect the sentinel lymph nodes in breast carcinoma and other malignant cancers. It is expected that with improvements in the optical imaging systems together with the use of a combination of multiple dyes and verification in large clinical trials, optical molecular imaging will become an essential tool for SLN detection and image-guided precise resection.

Network meta-analysis of novel and conventional sentinel lymph node biopsy techniques in breast cancer

Background

The aim of this network meta‐analysis was to compare the performance of blue dye alone or in combination with radioisotope (technetium‐99m, Tc) with three novel techniques for sentinel lymph node detection in breast cancer: indocyanine green fluorescence (ICG), superparamagnetic iron oxide (SPIO) nanoparticles and contrast‐enhanced ultrasound imaging (CEUS).

Methods

PubMed, Embase, the Cochrane Library, China Knowledge Research Integrated Database, ClinicalTrials.gov and OpenGrey databases were searched up to 31 November 2017, without language restriction. Studies that compared the detection performance of at least one of the novel methods (ICG, SPIO and CEUS) with that of traditional methods (blue dye and/or radioisotope) were included in network meta‐analysis.

Results

Thirty‐five studies were included. Pooled risk ratios (RRs) for Tc (1·09, 95 per cent c.i. 1·04 to 1·15), ICG (1·12, 1·07 to 1·16) and SPIO (1·09, 1·01 to 1·18) showed statistically better performance in detecting sentinel lymph nodes than blue dye alone. ICG had the lowest false‐negative rate, with a RR of 0·29 (0·16 to 0·54), followed by Tc (RR 0·44, 0·20 to 0·96) and SPIO (RR 0·45, 0·14 to 1·45), with blue dye alone as the reference group.

Conclusion

SPIO or ICG alone are superior to blue dye alone and comparable to the standard dual‐modality technique of blue dye with Tc.

Perioperative PET/CT lymphoscintigraphy and fluorescent real-time imaging for sentinel lymph node mapping in early staged colon cancer

Purpose

Using current optical imaging techniques and gamma imaging modalities, perioperative sentinel lymph node (SLN) identification in colon cancer can be difficult when the SLN is located near the primary tumour or beneath a thick layer of (fat) tissue. Sentinel lymph node mapping using PET/CT lymphoscintigraphy combined with real-time visualization of the SLN using near-infrared imaging has shown promising results in several types of cancer and may facilitate the successful identification of the number and location of the SLN in early colon cancer.

Methods

Clinical feasibility of PET/CT lymphoscintigraphy using preoperative endoscopically injected [⁸⁹Zr]Zr-Nanocoll and intraoperative injection of the near-infrared (NIR) tracer Indocyanine Green (ICG) was evaluated in ten early colon cancer patients. Three preoperative PET/CT scans and an additional ex vivo scan of the specimen were performed after submucosal injection of [⁸⁹Zr]Zr-Nanocoll. All SLNs and other lymph nodes underwent extensive pathological examination for metastases. A histopathological proven lymph node visible at preoperative PET/CT and identified at PET/CT of the specimen was defined as SLN.

Results

A total of 27 SLNs were harvested in seven out of eight patients with successful injection of both tracers. In one patient no SLNs were assigned preoperatively. In two patients injection of [⁸⁹Zr]Zr-Nanocoll failed due to incorrect needle positioning. Twenty-one (78%) SLNs were found intraoperatively using NIR-imaging. Eleven of the 27 (41%) SLNs were located near the primary tumour (< 2 cm). Those six SLNs not found intraoperatively with NIR-imaging were all located close to the tumour. In all seven patients at least one SLN could be assigned at preoperative imaging 24 h after tracer administration. One SLN contained metastases detected by immunohistochemistry. No metastases were found in the non-SLNs.

Conclusions

This study shows the potential of preoperative PET/CT lymphoscintigraphy to inform the surgeon about the number and location of SLNs in patients with early colon cancer. The additional use of NIR-imaging allows for intraoperative identification of these SLNs which are invisible with conventional white light imaging. Further research is necessary to improve and simplify the technique. We recommend perioperative SLN identification using a preoperative lymphoscintigraphy scan just before surgery approximately 24 h after injection. Additionally a postoperative scan of the specimen combined with intraoperative real-time NIR-imaging should be performed.

Electronic supplementary material

The online version of this article (10.1007/s00259-019-04284-w) contains supplementary material, which is available to authorized users.

Comparison of the indocyanine green dye method versus the combined method of indigo carmine blue dye with indocyanine green fluorescence imaging for sentinel lymph node biopsy in breast conservative therapy for stage ≤IIA breast cancer

BACKGROUND

Fluorescence imaging (FI) is one of the methods to identify sentinel lymph nodes (SLNs). However, the procedure is technically complicated and requires procedural skills, as SLN biopsy must be conducted in dim light conditions. As an improved version of this method, we introduced a combined method (Combined mixed dye and fluorescence; CMF) consisting of indigo carmine blue dye and FI. The direct visualization of SLNs under shadowless surgical light conditions is facilitated by the addition of the blue dye. We compared the SLN detection rates of CMF with that of the indocyanine green (ICG) dye method (ICG-D).

METHODS

A total of 202 patients with stage ≤IIA breast cancer who underwent breast conservative therapy with separate incision from January 2004 to February 2017 were reviewed. Details of the two methods are as follows: (1) ICG-D: 10 mg of ICG was used and the green-stained SLNs were resected via a 3-4 cm axillary incision; (2) CMF: A combination of 5 mg of ICG and 4-8 mg of indigo carmine was used. After a 1.5-2 cm incision was made near the point of disappearance of the fluorescence using Photodynamic Eye (PDE), the blue-stained SLNs were resected under shadowless surgical light conditions.

RESULTS

There were 92 ICG-D and 110 CMF cases. CMF resulted in a significantly higher SLN detection rate than ICG-D (96.4% vs. 83.7%; p = 0.003). This difference was particularly notable in those aged ≥60 years (98.3% vs. 74.3%) and individuals with body mass index (BMI) ≥25 kg/m² (90.3% vs. 58.3%).

CONCLUSION

CMF is an effective method to identify SLNs which is safe and efficient. CMF achieves a high SLN identification rate and most of this procedure is feasible under shadowless surgical light conditions. CMF can reliably perform SLN biopsy even in those aged ≥60 years and individuals with BMI ≥ 25 kg/m².

Noninvasive detection of cancer spread to lymph nodes: A review of molecular imaging principles and protocols

Identification of cancer spread to tumor-draining lymph nodes offers critical information for guiding treatment in many cancer types. Current clinical methods of nodal staging are invasive and can have substantial negative side effects. Molecular imaging protocols have long been proposed as a less invasive means of nodal staging, having the potential to enable highly sensitive and specific evaluations. This review article summarizes the current status and future perspectives for molecular targeted nodal staging.

Indocyanine green identification for tumor infiltration or metastasis originating from hepatocellular carcinoma

•

The indocyanine green-photodynamic eye (ICG-PDE) system was useful to clearly detect metastasis or tumor thrombus, as well as main tumor, originated from hepatocellular carcinoma and all lesions could be resected.

•

This system may be applied to improve determining the location of metastasis or tumor thrombus.

•

Tumor thrombus originated from hepatocellular carcinoma (HCC) in the portal vein or inferior vena cava could be well identified by ICG-PDE. The metastasized HCC lesion in an adrenal gland was clearly detected. All lesions could be completely resected.

•

ICG-PDE is a useful tool for detecting the precise tumor location even in extrahepatic tumor lesions or tumor thrombus, which is useful for deciding which parts to resect.

Introduction

The indocyanine green-photodynamic eye (ICG-PDE) system is useful to detect small hypervascular liver tumors, hepatocellular carcinoma (HCC), on the liver surface. This system may be also applied to improve determining the location of metastasis or tumor thrombus (TT). We herein report three case reports. ICG was administered preoperatively for functional testing and images of the tumor were observed during hepatectomy using a PDE camera.

Case series

The patient in case 1 exhibited advanced HCC with TT in the portal trunk. The TT in the right portal vein was clearly fluorescent by ICG-PDE and the right portal vein was adequately transected to remove TT. The patient in case 2 exhibited a large HCC in the right liver and the right adrenal gland was simultaneously swollen with enhancement. By confirming the fluorescent spot in the right adrenal gland, the metastasized lesion was completely resected. The patient in case 3 previously underwent central bi-segmentectomy, and lymph node metastasis and TT in the vena cava was observed during one-year follow-up. Although it was difficult to detect the definite margin of these lesions by the outline appearance, both lesions could be clearly observed with strong fluorescence and were completely resected.

Discussion and conclusion

ICG-PDE is a useful tool for detecting the precise tumor location even in extrahepatic tumor lesions, such as metastases or tumor thrombus, which is useful for deciding which parts to resect.

Feasibility of fluorescence lymph node imaging in colon cancer: FLICC

BACKGROUND

In colon cancer, appropriate tumour excision and associated lymphadenectomy directly impact recurrence and survival outcomes. Currently, there is no standard for mesenteric lymphadenectomy, with a lymph node yield of 12 acting as a surrogate quality marker. Our goal was to determine the safety and feasibility of indocyanine green (ICG) fluorescence imaging to demonstrate lymphatic drainage in colon cancer in a dose-escalation study.

METHODS

A prospective pilot study of colon cancer patients undergoing curative laparoscopic resection was performed. At surgery, peritumoural subserosal ICG injection was done to demonstrate lymphatic drainage of the tumour. A specialized fluorescence system excited the ICG and assessed lymphatics in real time. The primary outcome was the feasibility of ICG fluorescent lymphangiography for lymphatic drainage in colon cancer. Secondary outcomes were the optimal protocol for dose, injection site, and ICG lymphatic mapping timing.

RESULTS

Ten consecutive patients were evaluated (six males, mean age 69.5 years). In all, lymphatic channels were seen around the tumour to a varying extent. Eight (80%) had drainage to the sentinel node. In all cases where the lymphatic map was seen, there was no further spread 10 min after injection. In 2 patients (20%), additional lymph nodes located outside of the proposed resection margins were demonstrated. In both cases the resection was extended to include the nodes and in both patients these nodes were positive on histopathology. Factors contributing to reduced lymphatic visualization were inadequate ICG concentrations, excess India ink blocking drainage, and inflammation from tattoo placement.

CONCLUSIONS

ICG can be safely injected into the peritumoural subserosal and demonstrate lymphatic drainage in colon cancer. This proof of concept and proposed standards for the procedure can lead to future studies to optimize the application of image-guided precision surgery in colon cancer. Furthermore, this technique may be of value in indicating the need for more extended lymphadenectomy.

Visualization of murine lymph vessels using photoacoustic imaging with contrast agents

Metastasis frequently occurs even in the early stage of breast cancer. This research studied the feasibility of using photoacoustic (PA) imaging for identifying metastasis in the lymph vessels of mice. The photoacoustic efficiency of various contrast agents was investigated, and the influence of scattered light was evaluated by using a lymph vessel phantom. The lymph vessels of mice were then visualized using the selected contrast agents: indocyanine green (ICG) and gold nanorods (AuNR). The attenuation of the PA imaging was -1.90 dB/mm, whereas that of the fluorescence imaging was -4.45 dB/mm. The results indicate the potential of identifying sentinel lymph nodes by using PA imaging with these contrast agents.

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.

Fluoreszenz-Lymphographie

Der fluoreszierenden Farbstoff Indocyaningrün ermöglicht es uns, in Verbindung mit einer Infrarotkamera den Lymphabfluss zu beurteilen, den Sentinel-Lymphknoten zu entdecken, in neuen Operationstechniken die Funktionsfähigkeit der Lymphgefäße zu beurteilen, sowie die Wirksamkeit alter und neuer Behandlungsmethoden zu erkennen.

Role of Indocyanine Green in Fluorescence Imaging with Near-Infrared Light to Identify Sentinel Lymph Nodes, Lymphatic Vessels and Pathways Prior to Surgery - A Critical Evaluation of Options

Modern surgical strategies aim to reduce trauma by using functional imaging to improve surgical outcomes. This reviews considers and evaluates the importance of the fluorescent dye indocyanine green (ICG) to visualize lymph nodes, lymphatic pathways and vessels and tissue borders in an interdisciplinary setting. The work is based on a selective search of the literature in PubMed, Scopus, and Google Scholar and the authors' own clinical experience. Because of its simple, radiation-free and uncomplicated application, ICG has become an important clinical indicator in recent years. In oncologic surgery ICG is used extensively to identify sentinel lymph nodes with promising results. In some studies, the detection rates with ICG have been better than the rates obtained with established procedures. When ICG is used for visualization and the quantification of tissue perfusion, it can lead to fewer cases of anastomotic insufficiency or transplant necrosis. The use of ICG for the imaging of organ borders, flap plasty borders and postoperative vascularization has also been scientifically evaluated. Combining the easily applied ICG dye with technical options for intraoperative and interventional visualization has the potential to create new functional imaging procedures which, in future, could expand or even replace existing established surgical techniques, particularly the techniques used for sentinel lymph node and anastomosis imaging.

Comparison of sentinel lymph node biopsy guided by indocyanine green, blue dye, and their combination in breast cancer patients: a prospective cohort study

BACKGROUND

Recent studies show that near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has the potential to improve the performance of sentinel lymph node (SLN) mapping. The current cohort study was designed to assess the value of the combination of ICG and methylene blue (MB) dye in patients undergoing SLN biopsy.

METHODS

A prospective self-controlled trial was designed to detect the difference in the detection efficacies of ICG, MB, and combined ICG and MB (ICG + MB) navigation methods. Between 2010 and 2013, 198 consecutive early breast cancer patients eligible for sentinel lymph node biopsy were enrolled and 200 biopsy procedures were performed by injection of both ICG and MB. SLNs were searched and removed under the guidance of fluorescence and/or blue dye. The mapping characteristics, the detection rate of SLNs and positive SLNs, and the number of SLNs of ICG, MB, and ICG + MB were compared. Injection safety of ICG and MB was evaluated.

RESULTS

Fluorescence imaging of lymphatic flow, which is helpful to locate the incision site, could be seen in 184 of 200 procedures. The nodal detection rate of ICG, MB, and ICG + MB samples was 97, 89, and 99.5% (χ 2 = 26.2, p < 0.001), respectively, with the combination method yielding a superior identification result. The addition of ICG to the MB method resulted in the identification of more lymph nodes (median 3 versus 2) and more positive axillas (22.7% involved axillas were discovered by fluorescence only) than either method alone. No acute or chronic allergic reaction was observed in this study. However, 23 patients (23/82) who received breast-conserving therapy reported temporary skin staining, and 5 patients had permanent tattooing. Palpable subcutaneous nodules at the injection sites were reported in nine patients. There were no reports of skin necrosis.

CONCLUSIONS

The lymphatic navigation by ICG fluorescence detects SLNs at a high detection rate and improves the mapping performance when added to the MB method. The novel ICG + MB dual tracing modality, without involvement of radioactive isotopes, exhibits great potential as an alternative to traditional standard mapping methods.

TRIAL REGISTRATION

ACTRN12612000109808 . Retrospectively registered on 23 January 2012.