High-Resolution 18F-FDG PET/CT for Assessing Three-Dimensional Intraoperative Margins Status in Malignancies of the Head and Neck, a Proof-of-Concept

Abstract

The surgical treatment of head and neck malignancies relies on the complete removal of tumoral tissue, while inadequate margins necessitate the use of adjuvant therapy. However, most positive margins are identified postoperatively as deep margins, and intraoperative identification of the deep positive margins could help achieve adequate surgical margins and decrease adjuvant therapies. To improve deep-margin identification, we investigated whether the use of high-resolution preclinical PET and CT could increase certainty about the surgical margins in three dimensions. Patients with a malignancy of the head and neck planned for surgical resection were administered a clinical activity of 4MBq/kg 18F-FDG approximately one hour prior to surgical initiation. Subsequently, the resected specimen was scanned with a micro-PET-CT imaging device, followed by histopathological assessment. Eight patients were included in the study and intraoperative PET/CT-imaging of 11 tumoral specimens and lymph nodes of three patients was performed. As a result of the increased resolution, differentiation between inflamed and dysplastic tissue versus malignant tissue was complicated in malignancies with increased peritumoral inflammation. The current technique allowed the three-dimensional delineation of 18F-FDG using submillimetric PET/CT imaging. While further optimization and patient stratification is required, clinical implementation could enable deep margin assessment in head and neck resection specimens.

Machine Learning CT-Based Automatic Nodal Segmentation and PET Semi-Quantification of Intraoperative 68Ga-PSMA-11 PET/CT Images in High-Risk Prostate Cancer: A Pilot Study

“…Compared to the time-consuming frozen section technique, intraoperative molecular imaging can provide PET/CT data within 15 min from excision, thus reducing the operational time. Promising preliminary results have been described in the evaluation of PSMA-expressing prostate cancer [ 20 ], but also in breast cancer [ 17 ], head and neck cancer [ 18 ], pancreatic adenocarcinoma [ 19 ] and neuroendocrine tumors [ 20 ]. However, in order to accurately analyze the radiotracer uptake in PET/CT specimen images (i.e., lymph nodes) and obtain semiquantitative measurements that can improve the detection of disease localizations, accurate volumetric segmentation of 3D tomographic images is necessary.…”

Surgical margins in head and neck squamous cell carcinoma: a narrative review

“…Functional imaging (FI) technology, which encapsulates positron emission tomography (PET) and functional MRI technology, enables the capture of the tumor’s metabolic information 196 , 197 . PET-computed tomography (PET-CT), a molecular and FI modality, shows promise in assessing both superficial and deep margins of head and neck malignancies 176 , 198 . However, the exclusive use of PET-CT imaging is inadequate for distinguishing between inflammatory and malignant tissue 199 , 200 .…”

Image-guided surgery in oral cancer: toward improved margin control

“…This allowed the three-dimensional delineation of 18F-FDG using submillimetric PET/CT imaging, but differentiation between inflamed and dysplastic tissue versus malignant tissue was complicated due to increased peritumoral inflammation and thereby accurate prediction of the resection margin. The use of more tumor-specific PET-tracers is needed to resolve this problem [27].…”