Intraoperative Imaging Techniques to Improve Surgical Resection Margins of Oropharyngeal Squamous Cell Cancer: A Comprehensive Review of Current Literature

Abstract

Inadequate resection margins in head and neck squamous cell carcinoma surgery necessitate adjuvant therapies such as re-resection and radiotherapy with or without chemotherapy and imply increasing morbidity and worse prognosis. On the other hand, taking larger margins by extending the resection also leads to avoidable increased morbidity. Oropharyngeal squamous cell carcinomas (OPSCCs) are often difficult to access; resections are limited by anatomy and functionality and thus carry an increased risk for close or positive margins. Therefore, there is a need to improve intraoperative assessment of resection margins. Several intraoperative techniques are available, but these often lead to prolonged operative time and are only suitable for a subgroup of patients. In recent years, new diagnostic tools have been the subject of investigation. This study reviews the available literature on intraoperative techniques to improve resection margins for OPSCCs. A literature search was performed in Embase, PubMed, and Cochrane. Narrow band imaging (NBI), high-resolution microendoscopic imaging, confocal laser endomicroscopy, frozen section analysis (FSA), ultrasound (US), computed tomography scan (CT), (auto) fluorescence imaging (FI), and augmented reality (AR) have all been used for OPSCC. NBI, FSA, and US are most commonly used and increase the rate of negative margins. Other techniques will become available in the future, of which fluorescence imaging has high potential for use with OPSCC.

Real‐Time Laryngeal Cancer Boundaries Delineation on White Light and Narrow‐Band Imaging Laryngoscopy with Deep Learning

“…3,16,17 Several technologies have been employed to enhance the visibility of malignant tissue on the UADT mucosa (i.e., bioendoscopy, autofluorescence, contact endoscopy), yet each of these tools suffers from specific drawbacks that have limited their use. 18 Among those, NBI represents the most used and studied. 4,19,20 During surgery, NBI can provide accurate real-time tumor margin information and has been proven to reduce the rate of positive margins in laryngeal transoral surgery.…”

“…Indeed, the persistence of tumoral residue after this kind of procedure still represents a frequent issue 3,16,17 . Several technologies have been employed to enhance the visibility of malignant tissue on the UADT mucosa (i.e., bioendoscopy, autofluorescence, contact endoscopy), yet each of these tools suffers from specific drawbacks that have limited their use 18 …”

Hyperspectral imaging and evaluation of surgical margins: where do we stand?

“…Beyond the data on HSI tumor classification, the authors emphasize the strengths of HSI for digital staining to improve the visualization of tissue structures within slides that are difficult to identify with conventional stains [26]. Others see the special advantage of HSI in the possibility to analyze tissue sections within minutes [8]. One if not the major factor for recent advances in HSI head and neck cancer pathology classification stems from the usage of machine learning methods, which have been instrumental in realizing these advancements [11].…”

“…Consequently, new technologies that enable online, near-real-time, and reliable evaluation of the tumor margins are of significant interest [7]. Many approaches including but not limited to, narrow band imaging (NBI), high-resolution microendoscopic imaging, confocal laser endomicroscopy, intraoperative ultrasound, fluorescence-guided surgery, optical coherence tomography (OCT), and hyperspectral imaging (HSI) are currently being evaluated with the goal to increase the rate of negative head and neck cancer margins [8]. This review reflects the current status of using HSI for surgical margin evaluation.…”

3D Ultrasound and MRI in Assessing Resection Margins during Tongue Cancer Surgery: A Research Protocol for a Clinical Diagnostic Accuracy Study

“…The potential for positive surgical margins, which can lead to the necessity for additional treatments or even further surgery, underscores the critical need for more accurate and efficient intraoperative techniques. Therefore, the development and implementation of innovative approaches that can improve the rate of complete tumor resection are not only desirable but essential for enhancing surgical care and ultimately improving patient survival rates and quality of life [ 8 ].…”