Skin melanoma sentinel lymph node biopsy using real-time fluorescence navigation with indocyanine green and indocyanine green with human serum albumin

Current surgical management for melanoma

Melanoma is a major malignant cutaneous neoplasm with a high mortality rate. In recent years, the treatment of melanoma has developed dramatically with the invention of new therapeutic agents, including immune checkpoint inhibitors and molecular-targeted agents. These agents are available as adjuvant therapies for postoperative patients with stage IIB, IIC, and III melanomas. Furthermore, neoadjuvant therapy has been studied in several global clinical trials and has demonstrated promising and favorable clinical efficacy, mainly in patients with palpable regional lymph nodes. A recent large phase III clinical trial investigating early lymph node dissection for sentinel lymph node metastases demonstrated no survival benefits. Based on these data, surgery should be reconsidered as an appropriate treatment modality for melanoma. The need for invasive surgical procedures will be reduced with the invention of effective adjuvant and neoadjuvant therapies and novel clinical trial data on regional lymph node dissection. However, surgery still plays an important role in treating early-stage melanoma, accurately determining the disease stage, and effective palliative treatment for advanced melanoma. In this article, we focus on surgery for primary tumors, regional lymph nodes, and metastatic sites in an era of remarkably revolutionary drug treatments for melanoma.

Applications of near infrared and surface enhanced Raman scattering techniques in tumor imaging: A short review

Imaging technologies play a vital role in clinical oncology and have undergone massive growth over the past few decades. Research in the field of tumor imaging and biomedical diagnostics requires early detection of physiological alterations so as to provide curative treatment in real time. The objective of this review is to provide an insight about near infrared fluorescence (NIRF) and surface enhanced Raman scattering (SERS) imaging techniques that can be used to expand their capabilities for the early detection and diagnosis of cancer cells. Basic setup, principle and working of the instruments has been provided and common NIRF imaging agents as well as SERS tags are also discussed besides the analytical advantages/disadvantages of these techniques. This review can help researchers working in the field of molecular imaging to design cost effective fluorophores and SERS tags to overcome the limitations of both NIRF as well as SERS imaging technologies.

Fluorescent Versus Radioguided Lymph Node Mapping in Bladder Cancer

INTRODUCTION

The aim of the study was to compare 2 methods of the sentinel lymph node biopsy (SLNB) procedure in bladder cancer: we applied technetium radiocolloid (RadCol) detected by a gamma ray detection probe, and indocyanine green (ICG) detected by a near-infrared fluorescent (NIRF) camera.

MATERIAL AND METHODS

The SLNB was performed on 50 patients using the RadCol and the ICG, followed by a lymphadenectomy and a pathologic examination.

RESULTS

In the analyzed group of 47 patients (3 patients were excluded owing to the lack of lymphatic drainage from the tumor), the SLNB was performed using the 2 methods. The ICG with a NIRF-guided camera detected all sentinel lymph nodes (SLNs) in 46 cases, whereas RadCol detected them in 45 cases. In 12 (25.6%) of 47 patients, the ICG-fluorescent method revealed more SLNs than the RadCol method. In 8 (17%) patients, the SLNs revealed in the ICG fluorescence were metastatic. In 3 (6.4%) patients, we found SLNs outside the standard lymphadenectomy template, but a histopathologic examination showed they were negative for cancer. In 3 (6.4%) patients, the SLNs detected by both methods were negative for cancer, but other resected lymph nodes revealed metastases.

CONCLUSION

Our study shows that SLNB procedure with the RadCol or the ICG method is useful for the evaluation of lymph nodes in bladder cancer. The new ICG fluorescent technique with a NIRF camera system is safe, enables live view of the results of the procedure, and does not create additional costs. However, it highlights more lymph nodes than the radioactive method.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Comparison of Real-Time Fluorescent Indocyanine Green and (99m)Tc-Nanocolloid Radiotracer Navigation in Sentinel Lymph Node Biopsy of Penile Cancer

INTRODUCTION

The aim of this study was to compare lymphatic drainage patterns detected with fluorescent dye indocyanine green (ICG) with the lymphatic drainage patterns detected with radiotracer (99m)Tc-nanocolloid in dynamic sentinel node biopsy (DSNB) procedures.

PATIENTS AND METHODS

Fourteen patients with penile cancer and no palpable lymph nodes were included prospectively for DSNB. First, on the day of surgery (99m)Tc-nanocolloid was injected at the lesion site. Then, single photon emission computed tomography (SPECT) lymphoscintigraphy was performed. ICG was injected in the same manner as the radiotracer just before the surgery. In all cases partial penectomy and DSNB were performed. Sentinel lymph nodes (SLNs) were localized intraoperatively using the gamma-ray detection probe for radiocolloid and near infrared fluorescence (NIRF) camera for ICG.

RESULTS

Transcutaneously, lymphatic nodes were identified in all 14 patients using the gamma probe and in 10 patients using the NIRF camera. After skin incision, fluorescent nodes were observed using the NIRF camera in the remaining 4 patients. The examination led to identification of 32 SLNs in total using technetium and ICG and additionally 3 more nodes visible only using ICG. All SLNs found using SPECT were also fluorescent. In 3 patients ICG enabled only approximate localization of the SLNs. Of 35 SLNs, 30 were negative and 4 were positive for metastasis.

CONCLUSION

Our analysis of the effectiveness of ICG compared with radiocolloid in the DSNB for penile cancer indicates that they are comparable with some specific advantages and disadvantages. These findings must be studied further in a larger group of patients.

A review of performance of near-infrared fluorescence imaging devices used in clinical studies

Near-infrared fluorescence (NIRF) molecular imaging holds great promise as a new "point-of-care" medical imaging modality that can potentially provide the sensitivity of nuclear medicine techniques, but without the radioactivity that can otherwise place limitations of usage. Recently, NIRF imaging devices of a variety of designs have emerged in the market and in investigational clinical studies using indocyanine green (ICG) as a non-targeting NIRF contrast agent to demark the blood and lymphatic vasculatures both non-invasively and intraoperatively. Approved in the USA since 1956 for intravenous administration, ICG has been more recently used off label in intradermal or subcutaneous administrations for fluorescence imaging of the lymphatic vasculature and lymph nodes. Herein, we summarize the devices of a variety of designs, summarize their performance in lymphatic imaging in a tabular format and comment on necessary efforts to develop standards for device performance to compare and use these emerging devices in future, NIRF molecular imaging studies.

Intraoperative imaging-guided cancer surgery: from current fluorescence molecular imaging methods to future multi-modality imaging technology

Cancer is a major threat to human health. Diagnosis and treatment using precision medicine is expected to be an effective method for preventing the initiation and progression of cancer. Although anatomical and functional imaging techniques such as radiography, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) have played an important role for accurate preoperative diagnostics, for the most part these techniques cannot be applied intraoperatively. Optical molecular imaging is a promising technique that provides a high degree of sensitivity and specificity in tumor margin detection. Furthermore, existing clinical applications have proven that optical molecular imaging is a powerful intraoperative tool for guiding surgeons performing precision procedures, thus enabling radical resection and improved survival rates. However, detection depth limitation exists in optical molecular imaging methods and further breakthroughs from optical to multi-modality intraoperative imaging methods are needed to develop more extensive and comprehensive intraoperative applications. Here, we review the current intraoperative optical molecular imaging technologies, focusing on contrast agents and surgical navigation systems, and then discuss the future prospects of multi-modality imaging technology for intraoperative imaging-guided cancer surgery.

Usage of invisible near infrared light (NIR) fluorescence with indocyanine green (ICG) and methylene blue (MB) in urological oncology. Part 1

INTRODUCTION

Near infrared (NIR) technology has recently garnered much interest as a tool for intraoperative image-guided surgery in various surgical sub-disciplines. In urology, although nascent, NIR technology is also fostering much enthusiasm. This review discusses the two major fluorophores, indocyanine green (ICG) and methlyene blue (MB), with NIR guidance in experimental and clinical urology. The authors aim to illustrate and analyze the currently available initial studies to better understand the potential and practicability of NIR-guided imaging in the diagnosis and surgical outcome improvement. In the first part of the study we analyzed problems associated with sentinel lymph node biopsy, NIR-guided detection and imaging of tumors.

MATERIAL AND METHODS

PubMed and Medline databases were searched for ICG and MB use in urological settings, along with data published in abstracts of urological conferences.

RESULTS

Although NIR-guided ICG and MB are still in their initial phases, there have been significant developments in major domains of urology, including uro-oncological surgery: 1) sentinel lymph node biopsy, 2) detection and imaging of tumors.

CONCLUSIONS

Much like in other fields of surgical medicine, the application of NIR technology in urology is at its early stages. Therefore, more studies are needed to assess the true potential and limitations of the technology. However, initial developments hint towards a pioneering tool that may influence various aspects of urology.

Sentinel lymph node detection using laser-assisted indocyanine green dye lymphangiography in patients with melanoma

Introduction. Sentinel lymph node (SLN) biopsy is a vital component of staging and management of multiple cancers. The current gold standard utilizes technetium 99 (tech99) and a blue dye to detect regional nodes. While the success rate is typically over 90%, these two methods can be inconclusive or inconvenient for both patient and surgeon. We evaluated a new technique using laser-assisted ICG dye lymphangiography to identify SLN. Methods. In this retrospective analysis, we identified patients with melanoma who were candidates for SLN biopsy. In addition to tech99 and methylene blue, patients received a dermal injection of indocyanine green (ICG). The infrared signal was detected with the SPY machine (Novadaq), and nodes positive by any method were excised. Results. A total of 15 patients were evaluated, with 40 SLNs removed. Four patients were found to have nodal metastases on final pathology. 100% of these 4 nodes were identified by ICG, while only 75% (3/4) were positive for tech99 and/or methylene blue. Furthermore, none of the nodes missed by ICG (4/40) had malignant cells. Conclusion. ICG dye lymphangiography is a reasonable alternative for locating SLNs in patients with melanoma. Prospective studies are needed to better ascertain the full functionality of this technique.

Towards whole-body fluorescence imaging in humans

Dynamic near-infrared fluorescence (DNIF) whole-body imaging of small animals has become a popular tool in experimental biomedical research. In humans, however, the field of view has been limited to body parts, such as rheumatoid hands, diabetic feet or sentinel lymph nodes. Here we present a new whole-body DNIF-system suitable for adult subjects. We explored whether this system (i) allows dynamic whole-body fluorescence imaging and (ii) can detect modulations in skin perfusion. The non-specific fluorescent probe indocyanine green (ICG) was injected intravenously into two subjects, and fluorescence images were obtained at 5 Hz. The in- and out-flow kinetics of ICG have been shown to correlate with tissue perfusion. To validate the system, skin perfusion was modulated by warming and cooling distinct areas on the chest and the abdomen. Movies of fluorescence images show a bolus passage first in the face, then in the chest, abdomen and finally in the periphery (~10, 15, 20 and 30 seconds, respectively). When skin perfusion is augmented by warming, bolus arrives about 5 seconds earlier than when the skin is cooled and perfusion decreased. Calculating bolus arrival times and spatial fitting of basis time courses extracted from different regions of interest allowed a mapping of local differences in subcutaneous skin perfusion. This experiment is the first to demonstrate the feasibility of whole-body dynamic fluorescence imaging in humans. Since the whole-body approach demonstrates sensitivity to circumscribed alterations in skinperfusion, it may be used to target autonomous changes in polyneuropathy and to screen for peripheral vascular diseases.

One-year postoperative morbidity associated with near-infrared-guided indocyanine green (ICG) or ICG in conjugation with human serum albumin (ICG:HSA) sentinel lymph node biopsy

BACKGROUND

Sentinel lymph node biopsy (SLNB) is a standard staging procedure in breast cancer and skin melanoma patients. Radioactive colloid (RC) and blue dye are the routinely used markers for staining. The new dye used in this procedure, indocyanine green (ICG), seems to have true potential in near-infrared-guided SLNB. The aim of this study was to analyze 1-year morbidity after SLNB using RC and ICG or RC and ICG conjugated to human serum albumin (ICG:HSA) in breast cancer and skin melanoma patients.

METHODS

Forty-nine patients diagnosed with breast cancer and 10 patients with skin melanoma underwent SLNB using ICG with RC and ICG:HSA with RC. A total of 47 SLNB patients without the need for additional lymphadenectomy were evaluated approximately 1 year (11-13 months) for the presence of tattoo, extremity swelling, nerve dysfunction/pain, range of motion, and stiffness.

RESULTS

From the 47 patients examined, long-term morbidity was present in 3 (6.4%). In 1 patient, tattoo persisted for 11 months. Mild lymphedema was seen in 1 patient, and 1 patient exhibited minor functional deficit.

CONCLUSIONS

Using ICG or ICG:HSA seems to be safe, and long-term morbidity in SLNB patients is low. However, skin discoloration may appear as it does after the use of blue dye, and an increased number of harvested nodes might be associated with an increased number of iatrogenic lymphedema.

Dose optimization for near-infrared fluorescence sentinel lymph node mapping in patients with melanoma

BACKGROUND

Regional lymph node involvement is the most important prognostic factor in cutaneous melanoma. As only 20% of patients with melanoma have occult nodal disease and would benefit from a regional lymphadenectomy, the sentinel lymph node (SLN) biopsy was introduced. Near-infrared (NIR) fluorescence has been hypothesized to improve SLN mapping.

OBJECTIVES

  To assess the potential of intraoperative NIR fluorescence imaging to improve SLN mapping in patients with melanoma and to examine the optimal dose of indocyanine green adsorbed to human serum albumin (ICG:HSA).

METHODS

  Fifteen consecutive patients with cutaneous melanoma underwent the standard SLN procedure using (99m) technetium-nancolloid and patent blue. In addition, intraoperative NIR fluorescence imaging was performed after injection of 1·6 mL of 600, 800, 1000 or 1200 μmolL(-1) of ICG: HSA in four quadrants around the primary excision scar.

RESULTS

  NIR fluorescence SLN mapping was successful in 93% of patients. In one patient, no SLN could be identified using either conventional methods or NIR fluorescence. A total of 30 SLNs (average 2·0, range 1-7) were detected, 30 radioactive (100%), 27 blue (73%) and 30 NIR fluorescent (100%). With regard to the effect of concentration on signal-to-background ratios a trend (P=0·066) was found favouring the 600, 800 and 1000 μmol L(-1) groups over the 1200 μmol L(-1) group.

CONCLUSION

 This study demonstrates feasibility and accuracy of SLN mapping using ICG: HSA. Considering safety, cost and pharmacological characteristics, an ICG: HSA concentration of 600 μmolL(-1) appears optimal for SLN mapping in cutaneous melanoma, although lower doses need to be assessed.