Near-infrared fluorescence imaging for the prevention and management of breast cancer-related lymphedema: A systematic review

Bibliometric analysis of breast cancer-related lymphedema research trends over the last 2 decades

Objective

As breast cancer cases rise globally, post-mastectomy lymphedema garners increasing scholarly attention. This study aims to conduct a comprehensive bibliometric analysis of Breast Cancer-Related Lymphedema (BCRL) research from 2003 to 2022, identifying trends and providing global research insights for future studies.

Method

The literature for this analysis was extracted from the Web of Science (WoS) Core Collection, encompassing 1199 publications, including 702 articles and 101 reviews, totaling 803. Using advanced bibliometric tools such as VOSviewer and CiteSpace, quantitative and visual analyses were performed to map collaboration networks, research clusters, and emerging trends. The search strategy included specific terms related to lymphedema, breast cancer, and BCRL, ensuring a comprehensive representation of the research landscape.

Results

The bibliometric analysis revealed a steady increase in BCRL publications over the studied period, reaching a peak in 2018. The United States emerged as the leading contributor to BCRL literature, with China also demonstrating a significant presence. Collaboration networks were visualized, showcasing the interconnectedness of institutions and researchers globally. Key research hotspots identified include preventive strategies, complex decongestive therapy, and reconstructive interventions.

Conclusion

In conclusion, this pioneering bibliometric analysis provides a comprehensive overview of BCRL research trends and collaborations globally. The findings contribute valuable insights into the evolution of the field, highlighting areas of focus and emerging research themes. This study serves as a foundational resource for researchers, clinicians, and policymakers, fostering evidence-based practices and interventions for BCRL in the future.

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.

Early Detection of Breast Cancer-Related Lymphedema: Accuracy of Indocyanine Green Lymphography Compared with Bioimpedance Spectroscopy and Subclinical Lymphedema Symptoms

Introduction: The reported incidences of breast cancer-related lymphedema (LE) affecting the arms vary greatly. Reason for this variability includes different diagnostic techniques used across studies. In the current study, we compared the accuracy of indocyanine green lymphography (ICG_L) and bioimpedance spectroscopy (BIS) in detecting LE before presentation of clinical signs. Methods and Results: Patients with no initial detectable signs of clinical LE of their arms after axillary lymph node dissection or removal of >5 lymph nodes on sentinel lymph node biopsy were included. Subclinical LE was defined as BIS values outside the normal range [(≥7 units (or >10 units)] or a 7-unit (or 10 unit) change between two measurements. We tracked ICG_L and BIS measurements for 133 potentially affected arms (n = 123). ICG_L detected signs of lymphatic flow disruption in 63 arms (47%). Based on the BIS value of 7 units, 60 arms (45%) had values outside the normal range. When using ICG_L-identified LE cases as true positives, BIS had a 54% accuracy (area under the curve [AUC] = 0.54) in detecting LE. Accuracy was 61% for subclinical LE symptoms when compared with ICG_L (AUC = 0.62). Both BIS and subclinical LE symptoms had <0.70 AUC-receiver characteristic operator curve, suggesting that BIS and development of subclinical LE symptoms are not adequate for identifying patients with subclinical LE. Conclusion: ICG_L is a reliable diagnostic tool for detecting early signs of lymphatic flow disruption in subclinical LE. Utilizing ICG_L to diagnose subclinical LE followed by a personalized treatment plan may provide patients the best chance of preventing disease progression.

The Effectiveness of Fluoroscopy-Guided Manual Lymph Drainage as Part of Decongestive Lymphatic Therapy on the Superficial Lymphatic Architecture in Patients with Breast Cancer-Related Lymphoedema: A Randomised Controlled Trial

The objective of this trial was to investigate the effectiveness of fluoroscopy-guided manual lymph drainage (MLD), as part of decongestive lymphatic therapy (DLT), on the superficial lymphatic architecture in patients with chronic mild to moderate breast cancer-related lymphoedema (BCRL). This trial was a multicentre, double-blind, randomised controlled trial involving 194 participants with BCRL. Participants were randomised into (1) DLT with fluoroscopy-guided MLD (intervention group), (2) DLT with traditional MLD (control group), or (3) DLT with placebo MLD (placebo group). Superficial lymphatic architecture was evaluated as a secondary outcome, visualised by ICG lymphofluoroscopy at the baseline (B0), post-intensive (P), and post-maintenance phases (P6). Variables were (1) number of efferent superficial lymphatic vessels leaving the dermal backflow region, (2) total dermal backflow score, and (3) number of superficial lymph nodes. The traditional MLD group showed a significant decrease in the number of efferent superficial lymphatic vessels at P (p = 0.026), and of the total dermal backflow score at P6 (p = 0.042). The fluoroscopy-guided MLD and placebo group showed significant decreases in the total dermal backflow score at P (p < 0.001 and p = 0.044, respectively) and at P6 (p < 0.001 and p = 0.007, respectively); the placebo MLD group showed a significant decrease in the total number of lymph nodes at P (p = 0.008). However, there were no significant between-group differences for the changes in these variables. In conclusion, based on lymphatic architecture outcomes, the added value of MLD, in addition to the other parts of DLT, could not be demonstrated in patients with chronic mild to moderate BCRL.

Occurrence of breast-cancer-related lymphedema after reverse lymphatic mapping and selective axillary dissection versus standard surgical treatment of axilla: A two-arm randomized clinical trial

BACKGROUND

The need for axillary dissection (AD) is declining, but it is still essential for many patients with nodal involvement who risk developing breast-cancer-related lymphedema (BCRL) with lifelong consequences. Previous nonrandomized studies found axillary reverse mapping and selective axillary dissection (ARM-SAD) a safe and feasible way to preserve the arm's lymphatic drainage.

METHODS

The present two-arm prospective randomized clinical trial was held at a single comprehensive cancer center to ascertain whether ARM-SAD can reduce the risk of BCRL, compared with standard AD, in patients with node-positive breast cancer. Whatever the type of breast surgery or adjuvant treatments planned, 130 patients with nodal involvement met our inclusion criteria: 65 were randomized for AD and 65 for ARM-SAD. Twelve months after surgery, a physiatrist assessed patients for BCRL and calculated the excess volume of the operated arm. Lymphoscintigraphy was used to assess drainage impairment. Self-reports of any impairment were also recorded.

RESULTS

The difference in the incidence of BCRL between the two groups was 21% (95% CI, 3-37; p = .03). A significantly lower rate of BCRL after ARM-SAD was confirmed by a multimodal analysis that included the physiatrist's findings, excess arm volume, and lymphoscintigraphic findings, but this was not matched by a significant difference in patients' self-reports.

CONCLUSIONS

Our findings encourage a change of surgical approach when AD is still warranted. ARM-SAD may be an alternative to standard AD to reduce the treatment-related morbidity.

Delphi survey of intercontinental experts to identify areas of consensus on the use of indocyanine green angiography for tissue perfusion assessment during plastic and reconstructive surgery

BACKGROUND

In recent years, indocyanine green angiography (ICG-A) has been used increasingly to assist tissue perfusion assessments during plastic and reconstructive surgery procedures, but no guidelines exist regarding its use. We sought to identify areas of consensus and non-consensus among international experts on the use of ICG-A for tissue-perfusion assessments during plastic and reconstructive surgery.

METHODS

A two-round, online Delphi survey was conducted of 22 international experts from four continents asking them to vote on 79 statements divided into five modules: module 1 = patient preparation and contraindications (n = 11 statements); module 2 = ICG administration and camera settings (n = 17); module 3 = other factors impacting perfusion assessments (n = 10); module 4 = specific indications, including trauma debridement (n = 9), mastectomy skin flaps (n = 6), and free flap reconstruction (n = 8); and module 5 = general advantages and disadvantages, training, insurance coverage issues, and future directions (n = 18). Consensus was defined as ≥70% inter-voter agreement.

RESULTS

Consensus was reached on 73/79 statements, including the overall value, advantages, and limitations of ICG-A in numerous surgical settings; also, on the dose (0.05 mg/kg) and timing of ICG administration (∼20-60 seconds preassessment) and best camera angle (61-90^o) and target-to-tissue distance (20-30 cm). However, consensus also was reached that camera angle and distance can vary, depending on the make of camera, and that further research is necessary to technically optimize this imaging tool. The experts also agreed that ambient light, patient body temperature, and vasopressor use impact perfusion assessments.

CONCLUSION

ICG-A aids perfusion assessments during plastic and reconstructive surgery and should no longer be considered experimental. It has become an important surgical tool.

Use of fluorescence imaging during lymphatic surgery: A Delphi survey of experts worldwide

BACKGROUND

Fluorescence imaging with indocyanine green is increasingly used during lymphedema patient management. However, to date, no guidelines exist on when it should and should not be used or how it should be performed. Our objective was to have an international panel of experts identify areas of consensus and nonconsensus in current attitudes and practices in fluorescence imaging with indocyanine green use during lymphedema surgery patient management.

METHODS

A 2-round Delphi study was conducted involving 18 experts in the use of fluorescence imaging during lymphatic surgery, all asked to vote on 49 statements on patient preparation and contraindications (n = 7 statements), indocyanine green dosing and administration (n = 10), fluorescence imaging uses and potential advantages (n = 16), and potential disadvantages and training needs (n = 16).

RESULTS

Consensus ultimately was reached on 40/49 statements, including consistent consensus regarding the value of fluorescence imaging with indocyanine green in almost all facets of lymphedema patient management, including early detection, assessing disease extent, preoperative work-up, surgical planning, intraoperative guidance, monitoring short- and longer-term outcomes, quality control, and resident training. All experts felt it was very safe, while 94% felt it should be part of routine care and that indocyanine green was superior to colored dyes and ultrasound. Nonetheless, there also was consensus that limited high-quality evidence remains a barrier to its widespread use and that patients should still be provided with specific information and asked to sign specific consent for both fluorescence imaging and indocyanine green.

CONCLUSION

Fluorescence imaging with or without indocyanine green appears to have several roles in lymphedema prevention, diagnosis, assessment, and treatment.

Axillary reverse mapping using near-infrared fluorescence imaging in invasive breast cancer (ARMONIC study)

BACKGROUND

Axillary lymph node dissection (ALND) in patients with breast cancer has potential side effects, including upper-limb lymphedema. Axillary reverse mapping (ARM) is a technique that enables discrimination of the lymphatic drainage of the upper limb in the axillary lymph node basin from that of the breast. We aimed to evaluate ARM node identification by near-infrared (NIR) fluorescence imaging during total mastectomy with ALND and then to analyze potential predictive factors of ARM node involvement.

METHODS

The study enrolled 119 patients diagnosed with invasive breast cancer with an indication for ALND. NIR imaging using indocyanine green dye was performed in 109 patients during standard ALND to identify ARM nodes and their corresponding lymphatic ducts.

RESULTS

94.5% of patients had ARM nodes identified (95%CI = [88.4-98.0]). The ARM nodes were localized in zone D in 63.4% of cases. Metastatic axillary lymph nodes were found in 55% in the whole cohort, and 19.4% also had metastasis in ARM nodes. Two patients had metastatic ARM nodes but not in the remaining axillary lymph nodes. No serious adverse events were observed. Only the amount of mitosis was significantly associated with ARM node metastasis.

CONCLUSIONS

ARM by NIR fluorescence imaging could be a reliable technique to identify ARM nodes in real-time when ALND is performed. The clinical data compared with ARM node histological diagnosis showed only the amount of mitosis in the diagnostic biopsy is a potential predictive factor of ARM node involvement.

CLINICAL TRIAL REGISTRATION

NCT02994225.

Structural characterization and bioimaging of Zn2+ using meta-benziporphodimethene analogue

"Prevention is better than cure, especially when something has no cure." Cancer, in most patients is detected at the stage beyond which it becomes non-curative. Thus, the early detection of cancer cells can play a crucial role in enhancing the chances of a patient's survival. In this light, we present a non-fluorescent receptor employed for the detection of Zn²⁺ ion in MDA-MB-231 carcinoma cells that exhibits fluorescence turn-on behaviour upon binding with the metal ion. In this work, the synthesis of 11,16-bis(2,6-difluorobenzene)-6,6,21,21-tetramethyl-meta-benziporpho-6,21-dimethene and its Zn²⁺ chloride complex have been reported. The compounds were fully characterized using UV-Visible, NMR, IR and mass spectrometry. Furthermore, the X-ray polymorphs of meta-benziporphodimethene analogue have been added. The study of its bioimaging applications in MDA-MB-231 breast cancer cells for the detection of Zn²⁺ ions have been reported.

Dual Fluorescent Tracers for Surgical Guidance: Preventing Donor-site Lymphedema in Vascularized Lymph Node Transfer

Introduction:

Vascularized lymph node transfer (VLNT) restores physiological lymphatic function. Although effective, postoperative impairment of donor-site lymphatic function and iatrogenic lymphedema following lymph node transfer remains a pressing concern.

Methods:

Prospective analysis of VLNT patients undergoing dual fluorescent tracers-assisted harvest was performed at our institution from September 2013 to April 2022. Reverse lymphatic mapping of the lower extremity was performed with indocyanine green (ICG). Blue dye was utilized in both white light and near-infrared spectra for visualization of donor-site lymphatic structures. Demographics, intraoperative details, and surgical outcomes were recorded.

Results:

Twenty-five patients were included. Median age was 52.9 years with a body mass index of 29.1 kg/m² and mean follow-up of 44 months (range 24 to 90 months). Lymphedema stage ranged from Campisi 2 to 4. Inguinal VLNT was performed in 13 patients, and 12 patients received combined VLNT and free flap breast reconstruction. No patients required change in lymph node donor site intraoperatively. All ICG stained nodes were preserved in situ. No cases of iatrogenic lower extremity lymphedema were observed. Postoperative bioimpedance spectroscopy, circumferential, and volumetric measurements of the donor-site limb did not show evidence of subclinical or clinical lymphedema. The donor site healed appropriately in 92% of patients; one patient developed methylene blue-induced skin necrosis.

Conclusion:

Reverse lymphatic mapping and surgical guidance with dual ICG and blue dye fluorescent tracers provides surgeons with real-time surgical guidance without radioisotope, improves surgical visualization in both white light and near-infrared spectra, and avoids iatrogenic lymphatic dysfunction in the donor limb.

Near-Infrared Fluorescence Axillary Reverse Mapping (ARM) Procedure in Invasive Breast Cancer: Relationship between Fluorescence Signal in ARM Lymph Nodes and Clinical Outcomes

Simple Summary

Near-infrared fluorescence axillary reverse mapping (ARM) is a promising procedure for identification and preservation of arm lymphatic drainage during axillary lymph node dissection (ALND). We included 109 patients to analyze the indocyanine green fluorescence signal in ARM lymph nodes after resection. The fluorescence signal from ARM lymph nodes were compared with clinical findings to determine the importance of this criterion on the potential management of patients with ALND. ARM lymph nodes were identified in 94.5% of cases. The mean normalized fluorescence signal intensity value was 0.47 with no significant signal difference between metastatic and non-metastatic ARM lymph nodes. Only the preoperative diagnosis of metastasis in the axillary nodes of patients was significantly associated with a higher ARM node fluorescence signal intensity. Although preliminary results did not show that fluorescence signal intensity is a reliable diagnostic tool, the NIR fluorescence ARM procedure may be useful for ARM lymph node identification.

Abstract

The near-infrared (NIR) fluorescence axillary reverse mapping (ARM) procedure is a promising tool to identify and preserve arm lymphatic drainage during axillary lymph node dissection (ALND). The ARMONIC clinical trial was conducted to validate the technique on a large cohort of patients and to analyze the predictive clinical factors for ARM lymph node metastasis. For the first time, the fluorescence signal intensity from the ARM lymph nodes was measured and correlated with clinical findings. A total of 109 patients with invasive breast cancer and indications of mastectomy and ALND underwent the NIR fluorescence ARM procedure. Indocyanine green was administered by intradermal injection followed by intraoperative identification and resection of the ARM lymph nodes with NIR fluorescence camera guidance. The fluorescence signal intensity and signal distribution were then measured ex vivo and compared with clinical outcomes. ARM lymph nodes were successfully identified by fluorescence in 94.5% of cases. The mean normalized fluorescence signal intensity value was 0.47 with no significant signal difference between metastatic and non-metastatic ARM lymph nodes (p = 0.3728). At the microscopic level, the fluorescence signal distribution was focally intense in lymphoid tissue areas. Only the preoperative diagnosis of metastasis in the axillary nodes of patients was significantly associated with a higher ARM node fluorescence signal intensity (p = 0.0253), though it was not significantly associated with the pathological nodal (pN) status (p = 0.8081). Based on an optimal cut-off fluorescence value, the final sensitivity and specificity of the NIR fluorescence ARM procedure for ARM lymph node metastatic involvement were 64.7% and 47.3%, respectively. Although our preliminary results did not show that fluorescence signal intensity is a reliable diagnostic tool, the NIR fluorescence ARM procedure may be useful for ARM lymph node identification. Clinical trial registration: NCT02994225.

A meta-analysis of 37 studies on the effectiveness of microsurgical techniques for lymphedema

OBJECTIVES

Microsurgery is a new technique for lymphedema treatment. Its advantages and disadvantages remain controversial. This study sought to collect clinical data from patients who underwent lymphovenous bypass and vascularized lymph node transplantation to explore whether surgical procedures can effectively treat lymphedema.

METHODS

We performed a meta-analysis of the effectiveness of lymphatic microsurgery. We searched the databases of literature for articles in Chinese and English. These articles were graded for quality. Report details and outcomes were recorded. Data extraction, systematic review, and meta-analysis were performed.

RESULTS

Thirty-seven studies were included. Patients who underwent microsurgery had a significantly better chance of achieving an excellent result than patients who received conservative treatment (odds ratio=7.07). The affected limb circumference was reduced by approximately 44.68% after the microsurgery. After the microsurgery, 63% of the patients did not need physiotherapy, and 96% were free from painful skin infections. Lymphography showed that lymphatic transport capacity was enhanced. Moreover, 12% of the patients reported that edema reappeared in the long-term, 26% required reoperation for unsatisfactory results, and 32% experienced lymphatic leakage.

CONCLUSIONS

A vast majority of patients derive more benefit from lymphatic microsurgery than from conventional treatment. The advantages of lymphatic microsurgery outweigh the disadvantages for patients in the early and middle stages of chronic secondary lymphedema and patients in whom conventional treatment failed.

Prospective testing of clinical Cerenkov luminescence imaging against standard-of-care nuclear imaging for tumour location

In oncology, the feasibility of Cerenkov luminescence imaging (CLI) has been assessed by imaging superficial lymph nodes in a few patients undergoing diagnostic ¹⁸F-fluoro-2-deoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT). However, the weak luminescence signal requires the removal of ambient light. Here we report the development of a clinical CLI fiberscope with a lightproof enclosure, and the clinical testing of the setup using five different radiotracers. In an observational prospective trial (ClinicalTrials.gov identifier NCT03484884 ) involving 96 patients with existing or suspected tumours, scheduled for routine clinical FDG PET or ¹³¹I therapy, the level of agreement of CLI with standard-of-care imaging (PET or planar single-photon emission CT) for tumour location was 'acceptable' or higher (≥3 in the 1-5 Likert scale) for 90% of the patients. CLI correlated with the concentration of radioactive activity, and captured therapeutically relevant information from patients undergoing targeted radiotherapy or receiving the alpha emitter ²²³Ra, which cannot be feasibly imaged clinically. CLI could supplement radiological scans, especially when scanner capacity is limited.

Relationship Between the Circumference Difference and Findings of Indocyanine Green Lymphography in Breast Cancer-Related Lymphedema

BACKGROUND

Breast cancer-related lymphedema (BCRL) is a common complication. Indocyanine green (ICG) lymphography has been performed to assess lymphatic functionality. We found that some BCRL patients had a difference in circumference in partial regions only. The purpose of this study was to evaluate the patients with BCRL about the correlation between the difference in circumference and the findings of ICG lymphography.

METHODS

One hundred fifty-five patients with unilateral BCRL were enrolled in this study. We evaluated the differences in circumference taken at 4 parts on the upper limb (at around the wrist, forearm, elbow, and brachium). The difference in circumference was evaluated between the affected part (Caf) and the unaffected part (Cun). We calculated the circumference difference rate (CDR) as follows: CDR = 100 (Caf - Cun)/Caf. First, we classified each part of all BCRL patients (620 parts) based on the findings of ICG lymphography (linear, collateral, dermal back flow [DBF], and no enhancement) and evaluated the correlation. Second, in the patients with partial volume change, we compared the mean CDR in each part.

RESULTS

One hundred six parts were of a linear pattern, 31 parts were collateral, 350 parts were DBF, and 133 parts had no enhancement. The mean CDR of each finding was 3.3% in linear, 4.0% in collateral, 9.6% in DBF, and 9.4% in no enhancement. There was no significant difference between linear and collateral (P = 0.62), DBF, and no enhancement (P = 0.89) patterns. However, there was a significant difference between linear or collateral and DBF or no enhancement (all P < 0.001). In the 22 patients with distal DBF and proximal linear, the CDR was significantly higher in the forearm compared with the brachium (6.4% and 3.0%; P = 0.003). In the 26 patients with distal linear and proximal DBF, the CDR was significantly higher in the brachium compared with the forearm (4.3% and 7.7%; P = 0.005).

CONCLUSIONS

There was a significant correlation between the difference in circumference and the severity of ICG findings.

Proof of concept for the sapphire scalpel combining tissue dissection and optical diagnosis

OBJECTIVES

The development of compact diagnostic probes and instruments with an ability to direct access to organs and tissues and integration of these instruments into surgical workflows is an important task of modern physics and medicine. The need for such tools is essential for surgical oncology, where intraoperative visualization and demarcation of tumor margins define further prognosis and survival of patients. In this paper, the possible solution for this intraoperative imaging problem is proposed and its feasibility to detect tumorous tissue is studied experimentally.

METHODS

For this aim, the sapphire scalpel was developed and fabricated using the edge-defined film-fed growth technique aided by mechanical grinding, polishing, and chemical sharpening of the cutting edge. It possesses optical transparency, mechanical strength, chemical inertness, and thermal resistance alongside the presence of the as-grown hollow capillary channels in its volume for accommodating optical fibers. The rounding of the cutting edge exceeds the same for metal scalpels and can be as small as 110 nm. Thanks to these features, sapphire scalpel combines tissue dissection with light delivering and optical diagnosis. The feasibility for the tumor margin detection was studied, including both gelatin-based tissue phantoms and ex vivo freshly excised specimens of the basal cell carcinoma from humans and the glioma model 101.8 from rats. These tumors are commonly diagnosed either non-invasively or intraoperatively using different modalities of fluorescence spectroscopy and imaging, which makes them ideal candidates for our feasibility test. For this purpose, fiber-based spectroscopic measurements of the backscattered laser radiation and the fluorescence signals were carried out in the visible range.

RESULTS

Experimental studies show the feasibility of the proposed sapphire scalpel to provide a 2-mm-resolution of the tumor margins' detection, along with an ability to distinguish the tumor invasion region, which results from analysis of the backscattered optical fields and the endogenous or exogenous fluorescence data.

CONCLUSIONS

Our findings justified a strong potential of the sapphire scalpel for surgical oncology. However, further research and engineering efforts are required to optimize the sapphire scalpel geometry and the optical diagnosis protocols to meet the requirements of oncosurgery, including diagnosis and resection of neoplasms with different localizations and nosologies.

Indocyanine green lymphangiography is superior to clinical staging in breast cancer-related lymphedema

Precise staging of breast cancer-related lymphedema (BCRL) is important to guide treatment-decision making. Recent studies have suggested staging of BCRL using indocyanine green lymphangiography (ICG-L) based on the extent of lymphatic injury and dermal backflow patterns. Currently, the benefits of ICG-L compared to conventional clinical staging are unknown. For this study, we included 200 patients with unilateral BCRL. All BCRL patients were staged using ICG-L and clinical exam. The amounts of excess arm volume, fat mass and lean mass were compared between stages using Dual Energy X-Ray Absorptiometry. Multivariate regression models were used to adjust for confounders. For each increase in the patient's ICG-L stage, the excess arm volume, fat mass and lean mass was increased by 8, 12 and 6.5 percentage points respectively (P < 0.001). For each increase in the patient's clinical ISL stage, the volume was increased by 3.5 percentage points (P < 0.05), however no statistically significant difference in the lean and fat mass content of the arm was observed for ascending stages. However, the residual plots showed a high degree of variance for both ICG-L and clinical staging. This study found that ICG-L staging of BCRL was superior to clinical staging in forecasting BCRL excess arm volume, fat mass, and lean mass. However, there was a high degree of variance in excess arm volume, fat mass, and lean mass within each staging system, and neither the ICG-L nor clinical staging forecasted perfectly.

Comprehensive Review of Fluorescence Applications in Gynecology

Since the introduction of indocyanine green (ICG) as a fluorophore in near-infrared imaging, fluorescence visualization has become an essential tool in many fields of surgery. In the field of gynecology, recent new applications have been proposed and found their place in clinical practice. Different applications in gynecology were investigated, subcategorized, and overviewed concerning surgical applications and available dyes. Specific applications in which fluorescence-guided surgery was implemented in gynecology are described in this manuscript—namely, sentinel node biopsy, mesometrium visualization, angiography of different organs, safety issues in pregnant women, ureters visualization, detection of peritoneal metastases, targeted fluorophores for cancer detection, fluorescent contamination hysterectomy, lymphography for lower limb lymphedema prevention, tumor margin detection, endometriosis, and metastases mapping. With evolving technology, further innovative research on the new applications of fluorescence visualization in cancer surgery may help to establish these techniques as standards of high-quality surgery in gynecology. However, more investigations are necessary in order to assess if these innovative tools can also be effective to improve patient outcomes and quality of life in different gynecologic malignancies.

Prospective Validation of Indocyanine Green Lymphangiography Staging of Breast Cancer-Related Lymphedema

Simple Summary

Indocyanine green lymphangiography (ICG-L) allows real-time investigation of lymphatics; however, the applicability in evaluating breast cancer-related lymphedema (BCRL) is sparse and not well established. In this prospective study, we aimed to validate ICG-L assessment of BCRL in a large patient group. We found that evaluation of BCRL with ICG-L was easy and safe to perform in the outpatient clinic and provided unique disease information unobtainable by clinical assessment alone. Future studies that evaluate the efficacy of therapeutic treatments on lymphatic function morphology should incorporate lymphatic imaging as an outcome.

Abstract

Indocyanine green lymphangiography (ICG-L) allows real-time investigation of lymphatics. Plastic surgeons performing lymphatic reconstruction use the ICG-L for patient selection and stratification using the MD Anderson (MDA) and the Arm Dermal Backflow (ADB) grading systems. However, the applicability of ICG-L in evaluating breast cancer-related lymphedema (BCRL) is sparse and not well established. This study comprehensively examines the usability of ICG-L in the assessment of BCRL. We prospectively performed ICG-L in 237 BCRL patients between January 2019 and February 2020. The aim of this study was to assess the interrater and intrarater agreement and interscale consensus of ratings made using the MDA and ADB scales. Three independent raters performed a total of 2607 ICG-L assessments. The ICG-L stage for each grading system was correlated to the lymphedema volume to assess the agreement between the ICG-L stage and clinical severity. The interrater agreement was near perfect for the MDA scale (kappa 0.82–0.90) and the ADB scale (kappa 0.80–0.91). Similarly, we found a near-perfect intrarater agreement for the MDA scale (kappa 0.84–0.94) and the ADB scale (kappa 0.88–0.89). The agreement between the MDA and the ADB scales was substantial (kappa 0.65–0.68); however, the ADB scale systematically overestimated lower ICG-L stages compared to the MDA scale. The volume of lymphedema correlated slightly with MDA stage (Spearmans rho = 0.44, p < 0.001) and ADB stage (r_s = 0.35, p < 0.001). No serious adverse events occurred. The staging of BCRL with ICG-L is reliable, safe, and provides unique disease information unobtainable with clinical measurements alone. The MDA scale seems to provide better disease stratification compared to the ADB scale.

Prevention of Breast Cancer-Related Lymphedema

Tremendous progress has been made over the past several decades in the treatment of breast cancer. Mortality and recurrence rates continue to decline. Our ability to tailor patient- and tumor-specific treatments has rapidly advanced. The vast majority of our patients can safely have breast conservation. Unfortunately, for many patients, survivorship is burdened by ongoing quality-of-life issues. Most breast cancer patients are asymptomatic at presentation, and the onus is on us to preserve this. Surgery, radiation, and systemic therapy can result in long-term toxicities that can be amplified with multimodality approaches. We must strive to apply minimally effective therapies rather than a maximally tolerated approach. Breast cancer-related lymphedema (BCRL) is a particularly dreaded chronic complication. This review strives to give the reader a better understanding of BCRL and shed light on wisely choosing an integration of treatment modalities that minimizes BCRL risk. Key literature on emerging concepts is highlighted.

Quo Vadis, Nanoparticle-Enabled In Vivo Fluorescence Imaging?

The exciting advancements that we are currently witnessing in terms of novel materials and synthesis approaches are leading to the development of colloidal nanoparticles (NPs) with increasingly greater tunable properties. We have now reached a point where it is possible to synthesize colloidal NPs with functionalities tailored to specific societal demands. The impact of this new wave of colloidal NPs has been especially important in the field of biomedicine. In that vein, luminescent NPs with improved brightness and near-infrared working capabilities have turned out to be optimal optical probes that are capable of fast and high-resolution in vivo imaging. However, luminescent NPs have thus far only reached a limited portion of their potential. Although we believe that the best is yet to come, the future might not be as bright as some of us think (and have hoped!). In particular, translation of NP-based fluorescence imaging from preclinical studies to clinics is not straightforward. In this Perspective, we provide a critical assessment and highlight promising research avenues based on the latest advances in the fields of luminescent NPs and imaging technologies. The disillusioned outlook we proffer herein might sound pessimistic at first, but we consider it necessary to avoid pursuing "pipe dreams" and redirect the efforts toward achievable-yet ambitious-goals.

Does near-infrared fluorescent cholangiography with indocyanine green reduce bile duct injuries and conversions to open surgery during laparoscopic or robotic cholecystectomy? - A meta-analysis

BACKGROUND

Bile duct injury and conversion-to-open-surgery rates remain unacceptably high during laparoscopic and robotic cholecystectomy. In a recently published randomized clinical trial, using near-infrared fluorescent cholangiography with indocyanine green intraoperatively markedly enhanced biliary-structure visualization. Our systematic literature review compares bile duct injury and conversion-to-open-surgery rates in patients undergoing laparoscopic or robotic cholecystectomy with versus without near-infrared fluorescent cholangiography.

METHODS

A thorough PubMed search was conducted to identify randomized clinical trials and nonrandomized clinical trials with ≥100 patients. Because all near-infrared fluorescent cholangiography studies were published since 2013, only studies without near-infrared fluorescent cholangiography published since 2013 were included for comparison. Incidence estimates, weighted and unweighted for study size, were adjusted for acute versus chronic cholecystitis, and for robotic versus laparoscopic cholecystectomy and are reported as events/10,000 patients. All studies were assessed for bias risk and high-risk studies excluded.

RESULTS

In total, 4,990 abstracts were reviewed, identifying 5 near-infrared fluorescent cholangiography studies (3 laparoscopic cholecystectomy/2 robotic cholecystectomy; n = 1,603) and 11 not near-infrared fluorescent cholangiography studies (5 laparoscopic cholecystectomy/4 robotic cholecystectomy/2 both; n = 5,070) for analysis. Overall weighted rates for bile duct injury and conversion were 6 and 16/10,000 in near-infrared fluorescent cholangiography patients versus 25 and 271/10,000 in patients without near-infrared fluorescent cholangiography. Among patients undergoing laparoscopic cholecystectomy, bile duct injuries, and conversion rates among near-infrared fluorescent cholangiography versus patients without near-infrared fluorescent cholangiography were 0 and 23/10,000 versus 32 and 255/10,000, respectively. Bile duct injury rates were low with robotic cholecystectomy with and without near-infrared fluorescent cholangiography (12 and 8/10,000), but there was a marked reduction in conversions with near-infrared fluorescent cholangiography (12 vs 322/10,000).

CONCLUSION

Although large comparative trials remain necessary, preliminary analysis suggests that using near-infrared fluorescent cholangiography with indocyanine green intraoperatively sizably decreases bile duct injury and conversion-to-open-surgery rates relative to cholecystectomy under white light alone.

Impact of a compression garment, on top of the usual care, in patients with breast cancer with early disturbance of the lymphatic transport: protocol of a randomised controlled trial

INTRODUCTION

Breast cancer-related lymphoedema (BCRL) is a common phenomenon. When lymphoedema is diagnosed late, options for treatment are diminished. Therefore, early diagnosis and treatment are very important to alter the potential deleterious evolution. Lymphofluoroscopy visualises the superficial lymphatic architecture in detail, giving the opportunity to detect a disturbance in the lymphatic transport (ie, dermal backflow) before the lymphoedema is clinically visible.The main objective is to investigate if there is an additional effect of a compression garment on top of the usual care (ie, information and exercises) in patients with early disturbance of the lymphatic transport after breast cancer treatment. Development of clinical lymphoedema and/or deterioration of the dermal backflow visualised by lymphofluoroscopy is investigated.

METHODOLOGY

All patients scheduled for breast cancer surgery with unilateral axillary lymph node dissection or sentinel node biopsy in the Multidisciplinary Breast Clinic of the University Hospitals Leuven are being considered. Patients are assessed before surgery and at 1, 3, 6, 9, 12, 18, 24 and 36 months postoperatively. At each visit, a clinical assessment is performed determining the volume difference between both arms and hands (through circumference measurements and water displacement), the water content, the extracellular fluid, the pitting status and the skinfold thickness. Quality of life questionnaires are filled in. At each visit, a lymphofluoroscopy is performed as well. When a disturbance of the lymphatic transport is seen on lymphofluoroscopy, without the presence of clinical lymphoedema, the patient is randomised in either a control group receiving usual care or a preventive treatment group receiving usual care and a compression garment (whether or not combined with a glove).

ETHICS AND DISSEMINATION

The trial is conducted in compliance with the principles of the Declaration of Helsinki (2008), the principles of Good Clinical Practice and in accordance with all applicable regulatory requirements. This protocol has been approved by the Ethical Committee of the University Hospitals Leuven. Results will be disseminated by peer-reviewed scientific journals and presentation at international congresses.

TRIAL REGISTRATION NUMBER

NCT03210311 CONCLUSION: The investigators hypothesise that development of clinical BCRL can be prevented and/or the dermal backflow can be stabilised or improved, if a preventive treatment with compression garment is started in the early phase of disturbance.

Optical clearing for photoacoustic lympho- and angiography beyond conventional depth limit in vivo

Photoacoustic (PA) imaging (PAI) is an emerging powerful tool for noninvasive real-time mapping of blood and lymphatic vessels and lymph nodes in vivo to diagnose cancer, lymphedema and other diseases. Among different PAI instruments, commercially available raster-scanning optoacoustic mesoscopy (RSOM) (iThera Medical GmbH., Germany) is useful for high-resolution imaging of different tissues with high potential of clinical translation. However, skin light scattering prevents mapping vessels and nodes deeper than 1-2 mm, that limits diagnostic values of PAI including RSOM. Here we demonstrate that glycerol-based tissue optical clearing (TOC) overcomes this challenge by reducing light scattering that improves RSOM depth penetration. In preclinical model of mouse limb in vivo, the replacement of conventional acoustic coupling agents such as water on the mixture of 70 % glycerol and 30 % ultrasound (US) gel resulted in the increase of tissue imaging depth in 1.5-2 times with 3D visualization of vessels with diameter down to 20 μm. To distinguish blood and lymphatic networks, we integrated label-free PA angiography (i.e., imaging of blood vessels), which uses hemoglobin as endogenous contrast agent, with PA lymphography based on labeling of lymphatic vessels with exogenous PA contrast agents. Similar to well-established clinical lymphography, contrast agents were injected in tissue and taken up by lymphatic vessels within a few minutes that provided quick RSOM lymphography. Furthermore, co-injection of PA contrast dye and multilayer nanocomposites as potential low-toxic drug-cargo showed selective prolonged accumulation of nanocomposites in sentinel lymph nodes. Overall, our findings open perspectives for deep and high resolution 3D PA angio- and lymphography, and for PA-guided lymphatic drug delivery using new RSOM & TOC approach.

Visible-near infrared-II skull optical clearing window for in vivo cortical vasculature imaging and targeted manipulation

Skull optical clearing window permits us to perform in vivo cortical imaging without craniotomy, but mainly limits to visible (vis)-near infrared (NIR)-I light imaging. If the skull optical clearing window is available for NIR-II, the imaging depth will be further enhanced. Herein, we developed a vis-NIR-II skull optical clearing agents with deuterium oxide instead of water, which could make the skull transparent in the range of visible to NIR-II. Using a NIR-II excited third harmonic generation microscope, the cortical vasculature of mice could be clearly distinguished even at the depth of 650 μm through the vis-NIR-II skull clearing window. The imaging depth after clearing is close to that without skull, and increases by three times through turbid skull. Furthermore, the new skull optical clearing window promises to realize NIR-II laser-induced targeted injury of cortical single vessel. This work enhances the ability of NIR-II excited nonlinear imaging techniques for accessing to cortical neurovasculature in deep tissue.

Comparison of indocyanine green fluorescence and methylene blue dye in the detection of sentinel lymph nodes in breast cancer

Background

Previous studies have shown that sentinel lymph node biopsy (SLNB) can be successfully performed using methylene blue (MB); however, this method still has some drawbacks. Indocyanine green (ICG) fluorescence imaging, as a selective method, has the potential for guiding SLNB. This study aimed to compare the clinical sensitivity and efficacy between ICG and MB in SLNB in breast cancer.

Methods

A prospective study of 70 patients with biopsy-proven invasive breast cancer was conducted. Under the guidance of ICG and MB, administered by injection, SLNs were examined and removed. The detection rates, total number of SLNs detected, mean number of SLNs detected, and number of positive SLNs were compared between ICG and MB.

Results

The SLN detection rate was 100% and 93% (65/70) for ICG and MB, respectively. More SLNs were detected in the ICG group (243) than in the MB group (169). The mean number of SLNs detected with ICG and MB was 3.5±1.73 and 2.4±1.49, respectively. Moreover, there was a statistically significant difference between the number of SLNs detected using the two methods (t=6.648, P<0.05). Additionally, SLN metastasis was detected in 18 patients using ICG and 14 patients using MB; these patients immediately underwent axillary lymph node dissection (ALND). No postoperative complications were reported.

Conclusions

ICG demonstrated a higher detection rate and better accuracy, as well as a lower false negative rate, than MB in detecting SLNs in breast cancer. ICG has potential as an alternative tool that could be clinically applied to detect SLNs in breast cancer patients.

Application of imaging in lymphedema surgical therapies

Lymphedema is a chronic, progressive disease caused by primary or secondary reasons. It is currently uncurable and conservative compression therapy is generally applied. Lymphovenous anastomosis and vascularized lymph node transfer (VLNT) are two main surgical treatment that are used in addition to conservative therapy. Lymphovenous anastomosis involves the anastomosing remaining functional lymphatic vessels to vein. When the lymphatic vessels are greatly damaged and in no case can they be used for anastomosis, VLNT provide the affected area with lymph nodes from elsewhere to restore the drainage function. During all these procedures, a clear image to identify related lymphatic structures and venous vessels can be greatly useful for preoperative planning, intraoperative navigation, and postoperative evaluation. Lymphoscintigraphy used to be the gold standard in evaluating lymphedema and mapping lymphatic systems. But due to the downside of radiation, invasive operation and complication, other modalities are gaining attention. In this article, we reviewed the application of Indocyanine green (ICG) lymphography, ultrasound, magnetic resonance lymphography (MRL), and single-photon emission computed tomography-computed tomography (SPECT-CT) in the field of surgical therapy in lymphedema.

Resection of an axillary macrocystic lymphatic malformation in a 14-year-old girl using intraoperative indocyanine green lymphography

Lymphangioma is a malformation of the lymphatic system for which surgical excision is a possible treatment. However, complete excision may be hindered by the lesion's size, anatomic location, unclear borders, and invasion into adjacent tissues. We describe a 14-year-old girl who presented with a rapidly progressing axillary swelling. Magnetic resonance imaging and ultrasound revealed a lymphatic macrocystic multilocular lesion. After preoperative and intraoperative indocyanine green lymphography, a complete surgical excision was achieved without damage to collateral lymphatic channels or surrounding tissues. Intraoperative indocyanine green lymphography may be useful in achieving efficient and safe resection of lymphangioma without damaging unconnected lymphatics.

Application and Analysis of Biomedical Imaging Technology in Early Diagnosis of Breast Cancer

Breast cancer is the primary malignant tumor that endangers women's health. The incidence of breast cancer is increasing rapidly in recent years. Accurate disease evaluation before treatment is the key to the selection of treatment options. Biomedical imaging technology plays an irreplaceable role in the diagnosis and staging of tumors. Various imaging methods can provide excellent temporal and spatial resolution from multiple levels and perspectives and have become one of the most commonly used means of breast cancer early detection. With the development of radiomics, it has been found that early imaging diagnosis of breast cancer plays an important guiding role in clinical decision-making. The purpose of this study is to explore the characteristics of various breast cancer imaging technologies, promote the development of individualized accurate diagnosis and treatment of imaging, and improve the clinical application value of radiomics in the early diagnosis of breast cancer.

Correlation between patency and clinical improvement after lymphaticovenous anastomosis (LVA) in breast cancer-related lymphedema: 12-month follow-up

PURPOSE

Breast cancer-related lymphedema (BCRL) is caused by an interruption of the lymphatic system after breast cancer treatment. Lymphaticovenous anastomosis (LVA), by which one or more patent lymphatic collecting vessels are connected to subcutaneous veins, shows promising results. Postoperatively, the patency of these anastomosis can be evaluated; however, little is known concerning the long-term patency after LVA in patients with BCRL. The aim of this study was to analyse the long-term patency, quality of life (QoL) and arm circumference after LVA, and to explore differences between patent and non-patent anastomosis and its correlation with clinical improvement.

METHODS

Twenty-five patients underwent indocyanine green (ICG) lymphography, lymph ICF-questionnaire, and arm circumference measurement preoperatively and 12 months after the LVA procedure.

RESULTS

Seventy-six percent of the patients showed at least one patent anastomosis after 12 months. Quality of life according to the Lymph-ICF increased significantly (p < 0.000); however, arm circumference showed no significant decrease. Sixty-five percent discontinued wearing compression stockings. The patent anastomosis group, compared with the non-patent anastomosis group showed, without significance, more improvement in QoL, arm circumference, and discontinuation of compression stockings, as well as a lower rate of infections both pre- and postoperatively, a shorter duration of lymphedema preoperatively, and a higher rate of early lymphedema and ICG stage.

CONCLUSIONS

LVA showed an acceptable patency and positive correlation between a patent anastomosis and clinical improvement after 12 months. Further research with a larger study population is required to determine whether outcomes or patient characteristics significantly correlate with a patent anastomosis after LVA operation.