Estimating tongue deformation during laryngoscopy using a hybrid FEM-multibody model and intraoperative tracking - a cadaver study.

Throat tumour margin control remains difficult due to the tight, enclosed space of the oral and throat regions and the tissue deformation resulting from placement of retractors and scopes during surgery. Intraoperative imaging can help with better localization but is hindered by non-image-compatible surgical instruments, cost, and unavailability. We propose a novel method of using instrument tracking and FEM-multibody modelling to simulate soft tissue deformation in the intraoperative setting, without requiring intraoperative imaging, to improve surgical guidance accuracy. We report our first empirical study, based on four trials of a cadaveric head specimen with full neck anatomy, yields a mean TLE of 10.8 ± 5.5 mm, demonstrating methodological feasibility.

The art of specimen orientation: Two-dimensional maps for oropharynx squamous cell carcinoma.

The goal of surgical treatment for oropharynx squamous cell carcinoma (SCCa) is resection to negative margins. Current methods of orienting resection specimens often do not give a comprehensive view, especially in oropharynx SCCa where specimens can lack anatomic landmarks. We created standardized two-dimensional maps of oropharynx anatomy drawn to scale to improve communication between surgeons and pathologists. Notes regarding surgery including anatomic landmarks, areas of concern, additional margins, and relevant clinical information were added to the map. The maps guided pathology work-up, and the pathologist could communicate details back to the surgeon on how the specimen was sectioned or locations of microscopic foci to direct future treatment and clinical monitoring. The use of two-dimensional maps for oropharynx SCCa specimens offers a standardized solution to address the challenges of anatomic orientation. These maps summarized key pathological information, preserved clinical details from the specimens, and guided multidisciplinary conferences when planning adjuvant treatment.

First demonstration of a novel nerve-targeting fluorophore in a cohort of ex vivo human tissues.

Iatrogenic nerve injury is a common complication across all surgical specialties. Better nerve visualization and identification during surgery will improve outcomes and reduce nerve injuries. The Gibbs Laboratory at Oregon Health and Science University has developed a library of near-infrared, nerve-specific fluorophores to highlight nerves intraoperatively and aid surgeons in nerve identification and visualization; the current lead agent is LGW16-03. Prior to this study, testing of LGW16-03 was restricted to animal models; therefore, it was unknown how LGW16-03 performs in human tissue. To advance LGW16-03 to clinic, we sought to test this current lead agent in ex vivo human tissues from a cohort of patients and determine if the route of administration affects LGW16-03 fluorescence contrast between nerves and adjacent background tissues (muscle and adipose). LGW16-03 was applied to ex vivo human tissue from lower limb amputations via two strategies: (1) systemic administration of the fluorophore using our first-in-kind model for fluorophore testing, and (2) topical application of the fluorophore. Results showed no statistical difference between topical and systemic administration. However, in vivo human validation of these findings is required.

Fluorescence molecular optomic signatures improve identification of tumors in head and neck specimens.

Background: Fluorescence molecular imaging using ABY-029, an epidermal growth factor receptor (EGFR)-targeted, synthetic Affibody peptide labeled with a near-infrared fluorophore, is under investigation for surgical guidance during head and neck squamous cell carcinoma (HNSCC) resection. However, tumor-to-normal tissue contrast is confounded by intrinsic physiological limitations of heterogeneous EGFR expression and non-specific agent uptake. Objective: In this preliminary study, radiomic analysis was applied to optical ABY-029 fluorescence image data for HNSCC tissue classification through an approach termed "optomics." Optomics was employed to improve tumor identification by leveraging textural pattern differences in EGFR expression conveyed by fluorescence. The study objective was to compare the performance of conventional fluorescence intensity thresholding and optomics for binary classification of malignant vs. non-malignant HNSCC tissues. Materials and Methods: Fluorescence image data collected through a Phase 0 clinical trial of ABY-029 involved a total of 20,073 sub-image patches (size of 1.8 × 1.8 mm2) extracted from 24 bread-loafed slices of HNSCC surgical resections originating from 12 patients who were stratified into three dose groups (30, 90, and 171 nanomoles). Each dose group was randomly partitioned on the specimen-level 75%/25% into training/testing sets, then all training and testing sets were aggregated. A total of 1,472 standardized radiomic features were extracted from each patch and evaluated by minimum redundancy maximum relevance feature selection, and 25 top-ranked features were used to train a support vector machine (SVM) classifier. Predictive performance of the SVM classifier was compared to fluorescence intensity thresholding for classifying testing set image patches with histologically confirmed malignancy status. Results: Optomics provided consistent improvement in prediction accuracy and false positive rate (FPR) and similar false negative rate (FNR) on all testing set slices, irrespective of dose, compared to fluorescence intensity thresholding (mean accuracies of 89% vs. 81%, P = 0.0072; mean FPRs of 12% vs. 21%, P = 0.0035; and mean FNRs of 13% vs. 17%, P = 0.35). Conclusions: Optomics outperformed conventional fluorescence intensity thresholding for tumor identification using sub-image patches as the unit of analysis. Optomics mitigate diagnostic uncertainties introduced through physiological variability, imaging agent dose, and inter-specimen biases of fluorescence molecular imaging by probing textural image information. This preliminary study provides a proof-of-concept that applying radiomics to fluorescence molecular imaging data offers a promising image analysis technique for cancer detection in fluorescence-guided surgery.

Predictors of gastrostomy tube placement in patients with head and neck cancer undergoing resection and flap-based reconstruction: systematic review and meta-analysis.

BACKGROUND: Nutritional status may be impaired in patients with head and neck cancer undergoing surgical treatment, often necessitating gastrostomy tube (G-tube) placement. Identifying which patients will require a G-tube remains a challenge. This study identifies predictors of G-tube requirement in patients undergoing tumor resection and reconstruction with pedicled or free flaps. METHODS: Systematic review of the PubMed, Cochrane, and Scopus databases was performed of English language articles, discussing risk factors of perioperative G-tube placement among patients >18 years. Data on patient, tumor, and treatment factors, as well as need for G-tube, were collected. Univariable meta-analysis was conducted to identify predictors for G-tube placement. RESULTS: Eleven studies (1,112 patients) met inclusion criteria. Overall pooled prevalence of postoperative G-tube placement was 25%. Patients with advanced cancer stage IV/recurrence were more likely to require a G-tube (OR 2.81 [CI 1.03-7.69]; p<0.05), as were those who had undergone preoperative radiation (OR 3.55 [CI 2.03-6.20], p<0.05). Reconstruction with a radial forearm free flap was associated with a lower need for G-tube versus rectus abdominis (OR 0.25 [CI 0.08-0.83], p=0.02) and latissimus dorsi flap (OR 0.21 [CI 0.04-1.09], p=0.06). There was no difference in G-tube placement between those receiving pedicled flaps versus free flaps (OR 1.54 [CI 0.38-6.20], p=0.54). CONCLUSIONS: Among patients with head and neck cancer undergoing resection with immediate pedicled or free flap reconstruction, advanced tumor stage and history of prior radiation therapy are associated with increased likelihood of G-tube placement. More randomized controlled trials are needed to develop a decision-making algorithm.

Quantitative Evaluation of Aerosol Generation During In-Office Flexible Laryngoscopy.

Importance: Despite growing scientific knowledge and research, it is still unknown if office flexible laryngoscopy (FL) is aerosol generating and thereby potentially increases the risk of SARS-CoV-2 transmission. The limited literature that exists is conflicting, precluding formal conclusions. Objective: To determine whether FL is aerosol generating. Design, Setting, and Participants: This prospective cohort study included 134 patients seen in the otolaryngology clinic at a single tertiary care academic institution between February and May 2021. Two optical particle sizer instruments were used, quantifying particles ranging from 0.02 µm to 5 µm. Measurements were taken every 30 seconds, with sample periods of 15 seconds throughout the patient encounter. Instruments were located 12 inches from the patient's nares. Timing of events was recorded, including the start and end of physical examination, topical spray administration, start and end of laryngoscopy, and other potential aerosol-generating events (eg, coughing, sneezing). Data analysis was performed from February to May 2021. Exposures: Office examination and office FL. Main Outcomes and Measures: Bayesian online change point detection (OCPD) algorithm was used to detect significant change points (CPs) in this time-series data. The primary outcome was significant CP after FL compared with baseline physiologic variations, such as breathing and phonation. Results: Data were collected from 134 patients between February and May 2021. Ninety-one encounters involved FL. Of this group, 51 patients (56%) wore no mask over their mouth during FL. There was no statistically significant CP in either visits involving FL or visits where FL was not performed. Use of nasal spray did not result in CP in aerosol levels. Overall, neither the number of people present in the examination room, masks over patients' mouth, the duration of the visit, nor the duration of FL were associated with mean aerosol counts, regardless of the exposure. For larger aerosol sizes (≥1 µm), however, rooms with higher air exchange rates had significantly higher reductions in mean aerosol counts for visits involving FL. Conclusions and Relevance: The findings of this cohort study support that FL, including topical spray administration, is not a significant aerosol-generating procedure. The Bayesian OCPD model has a promising application for future aerosol studies in otolaryngology.

The submental island flap in head and neck reconstruction: A 10-year experience examining application, oncologic safety, and role of comorbidity.

Background: We present our experience on reconstructive versatility and risk of nodal transfer with the submental island flap (SIF). We also examine the role of comorbidity as a predictor of complications. Methods: Retrospective cohort study of patients undergoing SIF over 10-year period. Comorbidity determined using Adult Comorbidity Evaluation 27 index (ACE-27). Univariable/multivariable logistic regressions performed to determine association of these characteristics and rates of major complications. Results: Fifty-eight patients underwent SIF reconstruction, 27 (45%) patients had moderate/severe comorbidity, and 24 (41%) experienced major complication. Multivariable analysis identified ACE-27 scores >2 predictive of major flap complications (OR: 17.38, 95% CI: 1.96-153.74, p = .01) and medical complications (OR: 5.8, 95% CI: 1.11-30.23, p = .037). There were no cases of pathologic nodal transfer. Conclusion: The SIF is a versatile flap and oncologically safe in carefully selected patients. The ACE-27 index is strongly predictive of major postoperative complications. Level of Evidence: 4.

Quantifying Tumor and Vasculature Deformations during Laryngoscopy.

Retractors and scopes used in head and neck surgery to provide adequate surgical exposure also deform critical structures in the region. Surgeons typically use preoperative imaging to plan and guide their tumor resections, however the large tissue deformation resulting from placement of retractors and scopes reduces the utility of preoperative imaging as a reliable roadmap. We quantify the extent of tumor and vasculature deformation in patients with tumors of the larynx and pharynx undergoing diagnostic laryngoscopy. A mean tumor displacement of 1.02 cm was observed between the patients' pre- and intra-operative states. Mean vasculature displacement at key bifurcation points was 0.99 cm. Registration to the hyoid bone can reduce tumor displacement to 0.67 cm and improve carotid stem angle deviations but increase overall vasculature displacement. The large deformation results suggest limitations in reliance on preoperative imaging and that using specific landmarks intraoperatively or having more intraoperative information could help to compensate for these deviations and ultimately improve surgical success.

CT for estimating adequacy of lymph node dissection in patients with squamous cell carcinoma of the head and neck.

BACKGROUND: Indices obtained from lymph node dissection specimens, specifically lymph node yield (LNY) and lymph node ratio (LNR), have prognostic significance in the setting of head and neck squamous cell carcinoma (HNSCCa). However, there are currently no validated tools to estimate adequacy of planned lymph node dissection using preoperative data. The present study sought to evaluate CT-derived estimates of lymphatic tissue volumes as a preoperative tool to guide cervical node dissection. METHODS: Fifteen cervical lymph node dissections were performed in 14 subjects with HNSCCa. Preoperative CT-derived estimates of lymphatic tissue volumes were compared with gross pathology tissue volume estimates and pathologically-determined LNY. RESULTS: Resected tissue volume (calculated using the triaxial ellipsoid method) correlates with CT-derived preoperative lymphatic volume estimates (r = 0.74, p = 0.003) while LNY does not(r = - 0.12, p = 0.67). When excluding pathologically enlarged lymph nodes ("refined" data), a negative correlation was observed between refined CT-derived volume estimates and refined LNY (r = - 0.65, p = 0.009). CONCLUSION: In the setting of cervical lymph node dissection, CT-derived lymphatic volume estimates correlate with resected tissue volume, but refined CT-derived volume estimates correlate negatively with refined LNY. TRIAL REGISTRATION: Retrospectively registered. LEVEL OF EVIDENCE: 4.

First-In-Human Study in Cancer Patients Establishing the Feasibility of Oxygen Measurements in Tumors Using Electron Paramagnetic Resonance With the OxyChip.

OBJECTIVE: The overall objective of this clinical study was to validate an implantable oxygen sensor, called the 'OxyChip', as a clinically feasible technology that would allow individualized tumor-oxygen assessments in cancer patients prior to and during hypoxia-modification interventions such as hyperoxygen breathing. METHODS: Patients with any solid tumor at ≤3-cm depth from the skin-surface scheduled to undergo surgical resection (with or without neoadjuvant therapy) were considered eligible for the study. The OxyChip was implanted in the tumor and subsequently removed during standard-of-care surgery. Partial pressure of oxygen (pO2) at the implant location was assessed using electron paramagnetic resonance (EPR) oximetry. RESULTS: Twenty-three cancer patients underwent OxyChip implantation in their tumors. Six patients received neoadjuvant therapy while the OxyChip was implanted. Median implant duration was 30 days (range 4-128 days). Forty-five successful oxygen measurements were made in 15 patients. Baseline pO2 values were variable with overall median 15.7 mmHg (range 0.6-73.1 mmHg); 33% of the values were below 10 mmHg. After hyperoxygenation, the overall median pO2 was 31.8 mmHg (range 1.5-144.6 mmHg). In 83% of the measurements, there was a statistically significant (p ≤ 0.05) response to hyperoxygenation. CONCLUSIONS: Measurement of baseline pO2 and response to hyperoxygenation using EPR oximetry with the OxyChip is clinically feasible in a variety of tumor types. Tumor oxygen at baseline differed significantly among patients. Although most tumors responded to a hyperoxygenation intervention, some were non-responders. These data demonstrated the need for individualized assessment of tumor oxygenation in the context of planned hyperoxygenation interventions to optimize clinical outcomes.

Image-guided surgery in otolaryngology: A review of current applications and future directions in head and neck surgery.

Image-guided surgery (IGS) has become a widely adopted technology in otolaryngology. Since its introduction nearly three decades ago, IGS technology has developed rapidly and improved real-time intraoperative visualization for a diverse array of clinical indications. As usability, accessibility, and clinical experiences with IGS increase, its potential applications as an adjunct in many surgical procedures continue to expand. Here, we describe the basic components of IGS and review both the current state and future directions of IGS in otolaryngology, with attention to current challenges to its application in surgery of the nonrigid upper aerodigestive tract.

Clinicopathologic and Genomic Characterization of Inflammatory Myofibroblastic Tumors of the Head and Neck: Highlighting a Novel Fusion and Potential Diagnostic Pitfall.

Inflammatory myofibroblastic tumor (IMT) is a distinctive fibroblastic and myofibroblastic spindle cell neoplasm with an accompanying inflammatory cell infiltrate and frequent receptor tyrosine kinase activation at the molecular level. The tumor may recur and rarely metastasizes. IMT is rare in the head and neck region, and limited information is available about its clinicopathologic and molecular characteristics in these subsites. Therefore, we analyzed a cohort of head and neck IMTs through a multi-institutional approach. Fourteen cases were included in the provisional cohort, but 1 was excluded after molecular analysis prompted reclassification. Patients in the final cohort included 7 males and 6 females, with a mean age of 26.5 years. Tumors were located in the larynx (n=7), oral cavity (n=3), pharynx (n=2), and mastoid (n=1). Histologically, all tumors showed neoplastic spindle cells in storiform to fascicular patterns with associated chronic inflammation, but the morphologic spectrum was wide, as is characteristic of IMT in other sites. An underlying fusion gene event was identified in 92% (n=11/12) of cases and an additional case was ALK-positive by IHC but could not be evaluated molecularly. ALK represented the driver in all but 1 case. Rearrangement of ALK, fused with the TIMP3 gene (n=6) was most commonly detected, followed by 1 case each of the following fusion gene partnerships: TPM3-ALK, KIF5B-ALK, CARS-ALK, THBS1-ALK, and a novel alteration, SLC12A2-ROS1. The excluded case was reclassified as spindle cell rhabdomyosarcoma after detection of a FUS-TFCP2 rearrangement and retrospective immunohistochemical confirmation of rhabdomyoblastic differentiation, illustrating an important diagnostic pitfall. Two IMT patients received targeted therapy with crizotinib, with a demonstrated radiographic response. One tumor recurred but none metastasized. These results add to the growing body of evidence that kinase fusions can be identified in the majority of IMTs and that molecular analysis can lead to increased diagnostic accuracy and broadened therapeutic options for patients.

Tensor Veli Palatinopexy as a Novel Treatment for Eustachian Tube Dysfunction: A Cadaveric Feasibility Study.

OBJECTIVE: To demonstrate the feasibility of a novel procedure whereby a suture is placed transorally in the tensor veli palatini muscle to tighten it, thereby dilating the cartilaginous portion of the eustachian tube (ET). STUDY DESIGN: The study design was a prospective cadaveric experiment to examine the feasibility of a novel treatment for ET dysfunction. SETTING: Academic medical center in a research-oriented operating room with intraoperative computed tomography (CT) capabilities. METHODS: Seven fresh-frozen cadaver heads were obtained, each of which was thawed for 36 hours prior to use. The preprocedural volumes of the cartilaginous ET were measured by filling the ET with an iodine-containing radiocontrast agent via the nasopharynx and then obtaining CT images. Submucosal flaps in the soft palate were raised, and sutures were placed in the tensor veli palatini bilaterally to increase tension. After completion of the procedure, contrast placement and CT imaging were repeated. Three-dimensional models of the ETs were created, and the volumes were measured and compared. RESULTS: Of the 14 ETs evaluated, 13 showed an increase in postprocedure volume. On average, postprocedure volumes showed a 57% increase from preprocedure volumes (mean relative change, 57.1%; P = .013). CONCLUSION: Placement of a tension-holding suture in the tensor veli palatini muscle can reliably dilate the cartilaginous portion of the ET. Such a procedure may be useful in the treatment of ET dysfunction.

Spontaneous regression of squamous cell carcinoma in the setting of dental infection and needle biopsy.

To our knowledge, this is the first reported case of spontaneous regression of squamous cell carcinoma within a lymph node. We speculate that prior dental infection, fever, and biopsy incited an antitumor immune reaction.

A System for Characterizing Intraoperative Force Distribution During Operative Laryngoscopy.

OBJECTIVE: This study aimed to create and validate an integrated data acquisition system for gauging the force distribution between a laryngoscope and soft-tissue during trans-oral surgery. METHODS: Sixteen piezoresistive force sensors were interfaced to a laryngoscope and custom maxillary tooth guard. A protocol for calibrating the laryngoscope and maxilla sensors was developed using a motor-controlled linear stage and force measurements were validated against a digital scale. The system was initially tested during suspension laryngoscopy on three cadaver heads mounted on a cadaver head-holder. Intraoperative data was also collected from three patients undergoing head and neck tumor resection. RESULTS: Mean calibration error of the scope sensors was less than 150 g (n = 3) and mean maxilla sensor error was less than 200 g (n = 3). Peak scope mag-forces of 8.09 ± 6.61 kg and peak maxilla forces of 7.62 ± 4.57 kg were experienced during the cadaver trials. The peak scope sensor mag-force recorded during the intraoperative cases was 24.7 ± 4.53 kg, and the peak maxilla force was 22.0 ± 4.60 kg. CONCLUSION: The data acquisition system was successfully able to record intraoperative force distribution data. The usefulness of this technology in informing surgeons during trans-oral surgery should be further evaluated in patients with varying anatomic and procedural characteristics. SIGNIFICANCE: Creation of a low-cost, integrated force-sensing system allows for the characterization of retraction forces at anatomic sites including the pharynx and larynx, brain, and abdomen. Real-time force detection provides surgeons with valuable intraoperative feedback and can be used to improve deformation models at various anatomic sites.

Improving target localization during trans-oral surgery with use of intraoperative imaging.

PURPOSE: Trans-oral surgery provides a less invasive means for the surgical management of upper aerodigestive tract malignancies but is limited in its ability to readily assess submucosal tumor extent and location of critical structures intraoperatively. We sought to determine surgeons' baseline target localization accuracy during operative laryngoscopy with preoperative imaging alone and then assess for improvement in localization accuracy when presented with intraoperative CT imaging capturing soft tissue deformation. METHODS: Fiducial beads were placed submucosally in four cadaver heads. "Preoperative" (PO) and "intraoperative" (IO) neck CTs were acquired before and during suspension laryngoscopy using a CT-compatible laryngoscopy system. Surgeons attempted to localize submucosal fiducials beads using pins based on sequential review of PO and IO images. RESULTS: Mean total error (TE) decreased from 12.8 ± 9.9 to 10 ± 7.5 mm from PO to IO (P < 0.001), respectively. TE for base of tongue and vallecula decreased by 1.7 ± 6.7 mm (P = 0.015). Right-sided structures were most exposed by scope positioning and experienced a TE reduction of 4.8 ± 9.3 mm (P < 0.001). Task completion time decreased from PO to IO by 26% (P < 0.001). CONCLUSIONS: Intraoperative imaging significantly improves localization accuracy and task efficiency when targeting submucosal beads in cadaver heads during operative laryngoscopy.

Initial experience with image-guided surgical navigation in transoral surgery.

BACKGROUND: Surgical navigation using image guidance may improve the safety and efficacy of transoral surgery (TOS); however, preoperative imaging cannot be accurately registered to the intraoperative state due to deformations resulting from placement of the laryngoscope or retractor. This proof of concept study explores feasibility and registration accuracy of surgical navigation for TOS by utilizing intraoperative imaging. METHODS: Four patients undergoing TOS were recruited. Suspension laryngoscopy was performed with a CT-compatible laryngoscope. An intraoperative contrast enhanced CT scan was obtained and registered to fiducials placed on the neck, face, and laryngoscope. RESULTS: All patients were successfully scanned and registered. Registration accuracy within the pharynx and larynx was 1 mm or less. Target registration was confirmed by localizing endoscopic and surface structures to the CT images. Successful tracking was performed in all 4 patients. CONCLUSION: For surgical navigation during TOS, although a high level of registration accuracy can be achieved by utilizing intraoperative imaging, significant limitations of the existing technology have been identified. These limitations, as well as areas for future investigation, are discussed.

Radiation exposure alters airway deformability and bony structure displacement during laryngoscopy.

BACKGROUND: Prior therapeutic radiation exposure in the setting of head and neck malignancies is associated with difficult airway instrumentation. We sought to characterize the anatomic changes that produce this phenotype. STUDY DESIGN: Retrospective review. METHODS: Five individuals with prior radiation therapy to the upper aerodigestive tract (previously irradiated) and 10 with no prior history of therapeutic radiation exposure (nonirradiated) were enrolled. Computed tomography images obtained before and during laryngoscope insertion ("uninstrumented" and "instrumented", respectively) were used to reconstruct three-dimensional representations of the pharyngeal airway, hyoid, and mandible. RESULTS: In the instrumented state, pharyngeal airway volumes were significantly greater in nonirradiated subjects relative to previously irradiated subjects (P = .01), and overall translation of both the hyoid and mandible was also greater in nonirradiated subjects (P = .01 and .04, respectively). CONCLUSION: Individuals with prior therapeutic radiation exposure to the upper aerodigestive tract differ from nonirradiated subjects with respect to airway deformation and bony structure translation during laryngoscopy. LEVEL OF EVIDENCE: 4.

Multi-modal Framework for Image-guided Trans-oral Surgery with Intraoperative Imaging and Deformation Modeling.

Treatment of throat cancers have improved due to minimally-invasive trans-oral approaches. Surgeons rely on preoperative imaging to guide their resection; however, large tissue deformations occur during trans-oral procedures due to placement of necessary retractors and laryngoscopes which hinders the surgeon's ability to accurately assess tumor extent and location of critical structures. We propose an image-guided framework utilizing intraoperative imaging and deformation modeling to improve surgeon accuracy and confidence. A CT-compatible laryngoscopy system previously developed was evaluated in this framework. Intraoperative images were acquired during laryngoscopy; force-sensing capabilities were enabled in the laryngoscope; and tracking of the scope and anatomic features was trialed. Tissue deformation and displacement were quantified and determined to be extensive, with values <; 4.6 cm in the tongue, <; 1.8 cm in bony structures, and <; 108.9 cm3 in airway volume change. Surgical navigation using intraoperative imaging and tracking was evaluated. Preliminary assessment of deformation modeling showed potential to supplement intraoperative imaging. Future work will involve streamlined integration of the components of this framework.

Diagnostic Value of Lingual Tonsillectomy in Unknown Primary Head and Neck Carcinoma Identification After a Negative Clinical Workup and Positron Emission Tomography-Computed Tomography.

OBJECTIVE: Diagnostic rates of unknown primary head and neck carcinoma (UPHNC) using lingual tonsillectomy (LT) are highly variable. This study sought to determine the diagnostic value of LT in UPHNC identification using strict inclusion criteria and definitions to produce a more accurate estimate of diagnosis rate. METHODS: In this retrospective chart review, records of patients who underwent LT for UPHNC were reviewed. Inclusion criteria included absence of suspicious findings on physical exam and positron emission tomography-computed tomography as well as negative biopsies after panendoscopy and palatine tonsillectomy. Following inclusion criteria, 16 patients were reviewed. A systematic literature review on LT for the workup of CUP was also performed. RESULTS: LT was performed using transoral robotic surgery (TORS), transoral laser microsurgery (TLM), or transoral microsurgery with cautery (TMC). Following LT, primary tumor was identified in 4 patients out of 16. Detection rate by technique was 1/6, 2/7, and 1/3 for TORS, TLM, and TMC respectively. Postoperative bleeding occurred in three patients (19%); however, this was not related to the LT. Following literature review, 12 studies were identified; however, only 3 had enough data to compare against. All three studies had a cohort with suspicious findings on clinical exam. A total of 34 patients had a negative workup, with no suspicious findings on clinical exam and subsequently received an LT. CONCLUSION: This study suggests that LT should be considered initially in the diagnostic algorithm for UPHNC. This study can increase the patient size in this cohort by approximately 47%.