ICG-induced NIR fluorescence mapping in patients with head & neck tumors after the previous radiotherapy

Effect of radiation therapy on lymph node fluorescence in head and neck squamous cell carcinoma after intravenous injection of indocyanine green: a prospective evaluation

BACKGROUND

Indocyanine green (ICG)-guided surgery has proven effective in the identification of neoplastic tissues. The effect of radiation therapy (RT) on lymph node fluorescence after intravenous injection of ICG has not been addressed yet. The objective of this study was to evaluate the influence of RT on node fluorescence during neck dissection in head and neck squamous cell carcinoma (HNSCC).

RESULTS

Twenty-four patients with planned neck dissection for HNSCC were prospectively enrolled. Eleven were included without previous radiation therapy and 13 after RT. ICG was intravenously administered in the operating room. The resected specimen was analyzed by the pathology department to determine the status of each resected lymph node (invaded or not). The fluorescence of each resected node was measured in arbitrary units (AU) on paraffin blocs. The surface area (mm2) of all metastatic nodes and of the invaded component were measured. The values of these surface areas were correlated to fluorescence values. A total of 707 nodes were harvested, the mean fluorescence of irradiated nodes (n = 253) was 9.2 AU and of non-irradiated nodes (n = 454) was 9.6 AU (p = 0.63). Fifty nodes were invaded, with a mean fluorescence of 22 AU. The mean fluorescence values in the invaded irradiated nodes (n = 20) and the invaded non-irradiated nodes (n = 30) were 19 AU and 28 AU (p = 0.23), respectively. The surface area of metastatic nodes and of the invaded component were correlated to fluorescence values even after previous RT (p = 0.02).

CONCLUSION

No differences were observed between the fluorescence of irradiated and non-irradiated lymph nodes, including invaded nodes. ICG-guided surgery can be performed after failed RT.

TRIAL REGISTRATION

EudraCT ref. 2013-004498-29, registered 29 November 2013. https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-004498-29.

Current Approaches to Salvage Surgery for Head and Neck Cancer: A Comprehensive Review

Salvage surgeries of head and neck cancer are often complicated and do not always show decent results. This type of procedure is tough on the patient, as many crucial organs can be affected. A long period of reeducation usually follows the surgery because of the need to rehabilitate functions such as speech or swallowing. In order to lighten the journey of the patients, it is important to develop new technologies and techniques to ease the surgery and limit its damages. This seems even more crucial since progress has been made in the past years, allowing more salvage therapy to take place. This article aims at showing the available tools and procedures for salvage surgeries, such as transoral robotic surgery, free-flap surgery, sentinel node mapping, and many others, that help the work of the medical team to operate or obtain a better understanding of the status of the cancer when taken in charge. Yet, the surgical procedure is not the only thing determining the outcome of the operation. The patient themself and their cancer history also play an important part in the care and must be acknowledged.

Indocyanine green fluorescence-guided surgery in head and neck cancer: A systematic review

OBJECTIVE

To assess the feasibility and effectiveness of indocyanine green (ICG) for image-guided resection of head and neck cancer (HNC).

DATA SOURCES

PubMed, Embase, and Scopus databases.

REVIEW METHODS

Searches were conducted from database inception to February 2022. Patient and study characteristics, imaging parameters, and imaging efficacy data were extracted from each study.

RESULTS

Nine studies met inclusion criteria, representing 103 head and neck tumors. Weighted mean ICG dose and imaging time were 1.27 mg/kg and 11.77 h, respectively. Among the five studies that provided quantitative metrics of imaging efficacy, average ICG tumor-to-background ratio (TBR) was 1.56 and weighted mean ONM-100 TBR was 3.64. Pooled sensitivity and specificity across the five studies were 91.7 % and 71.9 %, respectively.

CONCLUSION

FGS with ICG may facilitate real-time tumor-margin delineation to improve margin clearance rates and progression-free survival. Future studies with validated, quantitative metrics of imaging success are necessary to further evaluate the prognostic benefit of these techniques.

[Surgical de-escalation for head and neck cancer surgery]

Head and neck cancer surgery often has functional and aesthetic consequences. De-escalation surgery is a major concern for surgeons with a constant desire to develop surgical techniques with less invasive approaches and to preserve anatomical structures as much as possible. This was made possible by the appearance of minimally transoral and endonasal surgery as well as by the limitation of the surgical procedure by neoadjuvant treatments or by the limitation of surgical excision without compromising the oncological outcome and patient survival. This evolution continues with the arrival of new technologies such as virtual reality or artificial intelligence.

Early glottic cancer recurrence: A critical review on its current management

INTRODUCTION

Recurrent early glottic cancer (rEGC) poses several issues in terms of timely diagnosis, correct re-staging, and treatment. We want to critically review the latest evidence about rEGC considering its epidemiology, biology, diagnostic challenges, and treatment strategies.

METHODS

A systematic search of the literature using PubMed from 1990 to October 31, 2020 was performed.

RESULTS

There are many different treatment options available (open surgery, transoral mini-invasive surgery, radiotherapy), and many factors related to the patient's status and previous treatments must be considered when planning the best management strategy for rEGC. While its overall prognosis remains satisfactory, it is of the utmost importance to appreciate all the clinical implications derived from the choice of the initial therapeutic modality, and from a correct primary and recurrent staging.

CONCLUSION

The balance between oncological and voice and swallowing functions represents the fundamental principle underlying rEGC management. Future studies should focus on molecular profiling of rEGC, and on the results of the emerging radiation delivery techniques and mini-invasive procedures.

Validation of a Three-Dimensional Head and Neck Spheroid Model to Evaluate Cameras for NIR Fluorescence-Guided Cancer Surgery

Near-infrared (NIR) fluorescence-guided surgery is an innovative technique for the real-time visualization of resection margins. The aim of this study was to develop a head and neck multicellular tumor spheroid model and to explore the possibilities offered by it for the evaluation of cameras for NIR fluorescence-guided surgery protocols. FaDu spheroids were incubated with indocyanine green (ICG) and then included in a tissue-like phantom. To assess the capability of Fluobeam® NIR camera to detect ICG in tissues, FaDu spheroids exposed to ICG were embedded in 2, 5 or 8 mm of tissue-like phantom. The fluorescence signal was significantly higher between 2, 5 and 8 mm of depth for spheroids treated with more than 5 µg/mL ICG (p < 0.05). The fluorescence intensity positively correlated with the size of spheroids (p < 0.01), while the correlation with depth in the tissue-like phantom was strongly negative (p < 0.001). This multicellular spheroid model embedded in a tissue-like phantom seems to be a simple and reproducible in vitro tumor model, allowing a comparison of NIR cameras. The ideal configuration seems to be 450 μm FaDu spheroids incubated for 24 h with 0.05 mg/mL of ICG, ensuring the best stability, toxicity, incorporation and signal intensity.

NIR Imaging of the Integrin-Rich Head and Neck Squamous Cell Carcinoma Using Ternary Copper Indium Selenide/Zinc Sulfide-Based Quantum Dots

The efficient intraoperative identification of cancers requires the development of the bright, minimally-toxic, tumor-specific near-infrared (NIR) probes as contrast agents. Luminescent semiconductor quantum dots (QDs) offer several unique advantages for in vivo cellular imaging by providing bright and photostable fluorescent probes. Here, we present the synthesis of ZnCuInSe/ZnS core/shell QDs emitting in NIR (~750 nm) conjugated to NAVPNLRGDLQVLAQKVART (A20FMDV2) peptide for targeting α_vβ₆ integrin-rich head and neck squamous cell carcinoma (HNSCC). Integrin α_vβ₆ is usually not detectable in nonpathological tissues, but is highly upregulated in HNSCC. QD-A20 showed α_vβ₆ integrin-specific binding in two-dimension (2D) monolayer and three-dimension (3D) spheroid in vitro HNSCC models. QD-A20 exhibit limited penetration (ca. 50 µm) in stroma-rich 3D spheroids. Finally, we demonstrated the potential of these QDs by time-gated fluorescence imaging of stroma-rich 3D spheroids placed onto mm-thick tissue slices to mimic imaging conditions in tissues. Overall, QD-A20 could be considered as highly promising nanoprobes for NIR bioimaging and imaging-guided surgery.