Indocyanine green near infrared-guided surgery in children, adolescents, and young adults with otolaryngologic malignancies.

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.

Fluorescent Molecular Imaging Can Improve Intraoperative Sentinel Margin Detection in Oral Squamous Cell Carcinoma.

In head and neck cancer, a major limitation of current intraoperative margin analysis is the ability to detect areas most likely to be positive based on specimen palpation, especially for larger specimens where sampling error limits detection of positive margins. This study aims to prospectively examine the clinical value of fluorescent molecular imaging to accurately identify "the sentinel margin," the point on a specimen at which the tumor lies closest to the resected edge in real-time during frozen section analysis. Methods: Eighteen patients with oral squamous cell carcinoma were enrolled into a prospective clinical trial and infused intravenously with 50 mg of panitumumab-IRDye800CW 1-5 d before surgery. Resected specimens were imaged in a closed-field near-infrared optical imaging system in near real-time, and custom-designed software was used to identify locations of highest fluorescence on deep and peripheral margins. The surgeon identified the sentinel margin masked to optical specimen mapping, and then the regions of highest fluorescence were identified and marked for frozen analysis. Final pathology based on specimen reconstruction was used as reference standard. Results: Resected specimens were imaged in the operating room, and fluorescence had a higher interobserver agreement with pathology (Cohen κ value 0.96) than the surgeon (Cohen κ value of 0.82) for the location of the closest margin. Plotting margin distance at the predicted sentinel margin location of each observer versus the actual closest margin distance at pathology demonstrated best correlation between fluorescence and pathology (R2 = 0.98) with surgeon (R2 = 0.75). Conclusion: Fluorescence imaging can improve identification of the sentinel margin in head and neck cancer resections, holding promise for rapid identification of positive margins and improved oncologic outcomes.

Clinical application of projection mapping technology for surgical resection of lung metastasis.

Indocyanine green fluorescent image-guided surgery was developed to identify primary and metastatic nodules of various malignancies. However, currently, surgeons need to identify the fluorescent image on a monitor, which impedes surgical procedures. Herein, we developed a novel projection mapping device that can cast the real-time fluorescent image onto the surface of the targeted organ. We performed surgical resection of a lung metastasis of hepatoblastoma using this technique. The projection mapping technique clearly detected the pulmonary lesion, and no other lesions were identified in the ipsilateral thorax. The patient is well and free of recurrence 2 years after surgery.