Defining the Genomic Landscape of Diffuse Sclerosing Papillary Thyroid Carcinoma: Prognostic Implications of RET Fusions.

BACKGROUND: Diffuse sclerosing papillary thyroid carcinoma (DSPTC) is an aggressive histopathologic subtype of papillary thyroid carcinoma. Correlation between genotype and phenotype has not been comprehensively described. This study aimed to describe the genomic landscape of DSPTC comprehensively using next-generation sequencing (NGS), analyze the prognostic implications of different mutations, and identify potential molecular treatment targets. METHODS: Tumor tissue was available for 41 DSPTC patients treated at Memorial Sloan Kettering Cancer Center between 2004 and 2021. After DNA extraction, NGS was performed using the Memorial Sloan Kettering Integrated Mutation Profiling of Actionable Cancer Targets platform, which sequences 505 critical cancer genes. Clinicopathologic characteristics were compared using the chi-square test. The Kaplan-Meier method and log-rank statistics were used to compare outcomes. RESULTS: The most common mutation was RET fusion, occurring in 32% (13/41) of the patients. Other oncologic drivers occurred in 68% (28/41) of the patients, including 8 BRAFV600E mutations (20%) and 4 USP8 mutations (10%), which have not been described in thyroid malignancy previously. Patients experienced RET fusion-positive tumors at a younger age than other drivers, with more aggressive histopathologic features and more advanced T stage (p = 0.019). Patients who were RET fusion-positive had a significantly poorer 5-year recurrence-free survival probability than those with other drivers (46% vs 84%; p = 0.003; median follow-up period, 45 months). In multivariable analysis, RET fusion was the only independent risk factor for recurrence (hazard ratio [HR], 7.69; p = 0.017). CONCLUSION: Gene-sequencing should be strongly considered for recurrent DSPTC due to significant prognostic and treatment implications of RET fusion identification. The novel finding of USP8 mutation in DSPTC requires further investigation into its potential as a driver mutation.

NaV1.7 targeted fluorescence imaging agents for nerve identification during intraoperative procedures.

Surgeries and trauma result in traumatic and iatrogenic nerve damage that can result in a debilitating condition that approximately affects 189 million individuals worldwide. The risk of nerve injury during oncologic surgery is increased due to tumors displacing normal nerve location, blood turbidity, and past surgical procedures, which complicate even an experienced surgeon's ability to precisely locate vital nerves. Unfortunately, there is a glaring absence of contrast agents to assist surgeons in safeguarding vital nerves. To address this unmet clinical need, we leveraged the abundant expression of the voltage-gated sodium channel 1.7 (NaV1.7) as an intraoperative marker to access peripheral nerves in vivo, and visualized nerves for surgical guidance using a fluorescently-tagged version of a potent NaV1.7-targeted peptide, Tsp1a, derived from a Peruvian tarantula. We characterized the expression of NaV1.7 in sensory and motor peripheral nerves across mouse, primate, and human specimens and demonstrated universal expression. We synthesized and characterized a total of 10 fluorescently labeled Tsp1a-peptide conjugates to delineate nerves. We tested the ability of these peptide-conjugates to specifically accumulate in mouse nerves with a high signal-to-noise ratio in vivo. Using the best-performing candidate, Tsp1a-IR800, we performed thyroidectomies in non-human primates and demonstrated successful demarcation of the recurrent laryngeal and vagus nerves, which are commonly subjected to irreversible damage. The ability of Tsp1a to enhance nerve contrast during surgery provides opportunities to minimize nerve damage and revolutionize standards of care across various surgical specialties.

Parotidectomy for deep lobe pleomorphic adenomas is associated with higher rates of complications and recurrence.

BACKGROUND: Pleomorphic adenoma (PA) is a common parotid tumor, yet due to the relative rarity of deep lobe PA (DLPA), there is a paucity of information about its clinical presentation and surgical outcomes. METHODS: We reviewed the charts of patients with previously untreated parotid PA between the years 1990 and 2015. Clinical parameters and surgical outcomes were compared between superficial lobe PA (SLPA) and DLPA. RESULTS: The cohort comprised 147 cases of DLPA and 222 cases of SLPA. DLPA were larger (median 2.6 cm vs. 2.0 cm, p < 0.001), more often discovered incidentally on imaging (33%, n = 48) and had unique presentations (pharyngeal mass, dysphagia, otalgia). Postsurgical complications were more frequently observed in DLPA (41% vs. 30% in SLPA, p = 0.025), mainly transient facial nerve weakness. DLPA also showed higher recurrence rates (n = 6, 4.1% vs. n = 1, 0.4%, p = 0.016). CONCLUSIONS: Parotidectomy for DLPA carries a higher risk of complications and recurrence compared to SLPA.

Osseous Maxillary Reconstruction with Immediate Dental Implant Placement: An Optimized Workflow for the Oncologic Patient.

INTRODUCTION: Maxillary reconstruction is a complex undertaking characterized by a 3-dimensional surgical site with deficiencies in multiple tissue types. Prior to virtual surgical planning(VSP), bony reconstruction was inaccurate and inefficient, thus reconstructions defaulted to soft tissue flaps or obturators. The current study describes an efficient and accurate approach to bony maxillary reconstruction with immediate dental implant placement(IDIP). METHODS: A reconstructive workflow was developed for osseous reconstruction to improve functional and aesthetic outcomes. Critical aspects include VSP, 3-D printed plates and IDIP. Review of a prospectively maintained database identified patients who underwent osseous maxillary reconstruction with a fibula flap and immediate dental implants from 2017-2022, with a focus on oncologic characteristics and reconstructive outcomes. RESULTS: During the study, 20 patients underwent maxillary reconstruction with VSP and IDIP. One dental implant out of 55 failed to osseointegrate and no flaps were lost. Three patients suffered partial loss of the fibula skin island; one required palatal closure with a radial forearm flap, and two were managed with outpatient debridement. Fifteen patients achieved either an interim or final retained dental prosthesis. All prostheses achieved acceptable aesthetic results without the instability associated with non-bone borne devices(e.g.dentures/obturators). No patients experienced delays in oncologic treatment. CONCLUSIONS: VSP technology has enabled surgeons to replace like with like to achieve better outcomes with acceptable morbidity for maxillary defects. IDIP provides all patients an opportunity for a fixed prosthesis even though not all complete the process. This maxillary reconstruction workflow can be safely accomplished in oncologic patients with promising and effective early results.

A Prospective Double-Blinded Comparison of Reflectance Confocal Microscopy with Conventional Histopathology for In Vivo Assessment in Oral Cancer.

PURPOSE: We investigated reflectance confocal microscopy (RCM) as a possible noninvasive approach for the diagnosis of cancer and real-time assessment of surgical margins. EXPERIMENTAL DESIGN: In a phase I study on 20 patients, we established the RCM imaging morphologic features that distinguish oral squamous cell carcinoma (OSCC) from normal tissue with a newly developed intraoral RCM probe. Our subsequent phase II prospective double-blinded study in 60 patients tested the diagnostic accuracy of RCM against histopathology. Five RCM videos from the tumor and five from normal surrounding mucosa were collected on each patient, followed by a 3-mm punch biopsy of the imaged area. An experienced RCM reader, who was blinded to biopsy location and histologic diagnosis, examined the videos from both regions and classified each as "tumor" or "not tumor" based on RCM features established in phase I. Hematoxylin and eosin slides from the biopsies were read by a pathologist who was blinded to RCM results. Using histology as the gold standard, we calculated the sensitivity and specificity of RCM. RESULTS: We report a high agreement between the blinded readers (95% for normal tissue and 81.7% for tumors), high specificity (98.3%) and negative predictive values (96.6%) for normal tissue identification, and high sensitivity (90%) and positive predictive values (88.2%) for tumor detection. CONCLUSIONS: RCM imaging is a promising technology for noninvasive in vivo diagnosis of OSCC and for real-time intraoperative evaluation of mucosal surgical margins. Its inherent constraint, however, stems from the diminished capability to evaluate structures located at more substantial depths within the tissue.