Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Program Number: B054
Session Name: Poster Session
Intraoperative molecular imaging can detect large nerve perineural invasion: A Case Report
Carleigh R Burns, BS; Aviva S Mattingly, MD; Kim Ely, MD; Nicole Meeks, MD; Brandee Brown, BS; Georgii Vasiukov, MD, PhD; Eben Rosenthal, MD; Michael C Topf, MD, MSCI; Vanderbilt University Medical CenterBackground: Perineural invasion (PNI) in head and neck squamous cell carcinoma (HNSCC) results in worse overall survival and diagnosis requires resection and evaluation by microscopy. Emerging techniques in intraoperative molecular imaging can be used for non-destructive identification of PNI. In this case, we report subclinical hypoglossal nerve PNI that was detected using intraoperative fluorescence.
Methods: A 63-year-old male with history of cT4aN0 p16-positive squamous cell carcinoma of the left base of tongue was diagnosed with persistent disease following definitive chemoRT. He was scheduled for total glossectomy, left neck dissection, and anterolateral thigh (ALT) free flap reconstruction. He was enrolled in a clinical trial (NCT05945875) using an optically EGFR targeted antibody, Panitumumab-IRDye800 (pan800). This was infused six days prior to surgery. Intraoperatively, pan800 was visualized in real time using PDE-GEN3 near-infrared fluorescence (NIR) imaging system.
Results: During the open left base of tongue resection, the proximal hypoglossal nerve was normal appearing, but grossly entered the tumor distally and therefore was resected. The wound bed including the proximal aspect of the hypoglossal nerve was imaged using NIR and demonstrated a strong fluorescence signal compared to the background tissue as well as the nearby spinal accessory nerve, which raised concern for subclinical perineural invasion. This imaging guided the surgeon towards biopsy of the proximal left hypoglossal nerve which was positive for squamous cell carcinoma on frozen section analysis (Figure 1). Therefore, further re-resection of the hypoglossal nerve was performed with a final negative nerve margin more proximally. Postoperatively, ex vivo immunofluorescence imaging confirmed the presence of pan800 within the initial positive nerve margin (Figure 2).
Conclusions: This case shows the feasibility of intraoperative fluorescence as a method to help identify subclinical perineural invasion. The nerve was previously sacrificed in this case, but this does provide an opportunity for non-destructive intraoperative identification.
Figure 1. Frozen section biopsy of hypoglossal nerve imaged on back table with PDE prior to pathology processing (A) and p40 immunostain used to highlight squamous cells showing evidence of carcinoma (B)
Figure 2. Ex vivo H&E (A) and immunofluorescence (B) imaging confirmed the presence of carcinoma and corresponding pan800 within the initial positive nerve margin.