Objective: Head and neck cancers represent critical challenges due to the restricted anatomical space in children and the proximity of critical neurovascular structures which can compromise complete tumor resection. Applications of Indocyanine green (ICG) near infrared (NIR) fluorescent image-guided surgery (FGS) have recently expanded into the pediatric population, emphasizing its relevance for tumor delineation and evaluation of tissue perfusion. The objectives of the present study are twofold. First, we aim to assess the role of ICG NIR imagery in identifying neoplastic disease and second, to evaluate its role as an adjunct to identify metastatic deposits in cervical lymph node in children, adolescents, and young adults with head and neck cancers.
Methods: Eight patients with head and neck malignancies underwent ICG NIR FGS, between January 2019 and November 2021. ICG NIR findings were compared with preoperative cross-sectional imaging and results of operative tissue pathology analyses.
Results: All primary tumors were identified on preoperative imaging and intraoperatively with ICG NIR; however, for one case, extension of tumor was revealed with ICG NIR and confirmed by histopathological examination but was not otherwise visible on preoperative imaging or with naked eye visual and tactile assessment. ICG NIR assisted the decision process in a difficult case for which curative resection, without significant functional morbidity and potential mortality, was unrealistic. Although ICG NIR evaluation of the surgical bed did not display residual tumor, margins were found positive in two cases. ICG NIR evaluation for local metastases changed the surgical strategy in one patient by prompting conversion to bilateral neck dissections. The sensitivity of preoperative multimodality imaging to identify cervical levels of invasion was 75% with a specificity of 70%, a PPV of 33%, a NPV of 78% and an accuracy of 72%. The ICG NIR sensitivity was 83%, its specificity was 88% with a PPV of 91%, a NPV of 80% and an accuracy of 86%. The combination of preoperative multimodality imaging with ICG NIR findings led to a sensitivity of 83%, specificity of 88% and accuracy of 86%.
Conclusion: This case series provides a proof of concept of the feasibility of ICG NIR, as an adjunct in tumor and local metastases identification in young patients with head and neck tumors. It revealed to be feasible and safe for intra-operative tumor identification, thus guiding and facilitating resection. However, it showed some limitations in precise tumor margin assessment. The combination of preoperative multimodality imaging with ICG NIR findings improved local metastases localization.
Keywords: Fluorescent image-guided surgery; Indocyanine green; Near infrared imaging; Pediatric head and neck tumors; Pediatric parotid malignancies.
Copyright © 2022. Published by Elsevier B.V.