Free flap reconstruction following head and neck trauma.

BACKGROUND: Free flap (FF) reconstruction of traumatic injuries to the head and neck is uncommon. METHODS: Multi-institutional retrospective case series of patients undergoing FF reconstruction for a traumatic injury (n = 103). RESULTS: Majority were gunshot wounds (GSW; 85%, n = 88) and motor vehicle accidents (11%, n = 11). Majority underwent osseous reconstruction (82%, n = 84). FF failures (9%, n = 9/103) occurred in GSW patients (100%, n = 9/9) and when multiple subsites were injured (89%, n = 8/9). Preoperative antibiotics correlated with lower rates of a neck washouts (4% vs. 19%) (p = 0.01) and 30-day readmissions (4% vs. 17%) (p = 0.02). CONCLUSIONS: All FF failures occurred in the setting of a GSW and the majority involved multiple subsites. Preoperative antibiotics correlated with lower rates of postoperative washout procedures and 30-day readmission.

Establishing a role for the oral microbiome in infectious complications following major oral cavity cancer surgery.

Surgery forms the backbone of treatment for most locoregional or advanced oral cavity squamous cell carcinoma. Unfortunately, infectious complications (including orocutaneous fistulas) are common following such extensive surgery and can afflict over half of patients. These complications can lead to delays in adjuvant treatment, prolonged hospitalization, reconstructive failure, and decreased quality of life. The frequency and morbidity associated with infectious complications has led to the search for pre-disposing risk factors; and, several have been identified, including both patient (e.g. diabetes) and surgical (e.g. operative time) factors. However, these findings are inconsistently reproduced, and risk factor modification has had a limited impact on rates of infectious complications. This is striking given that the likely contaminant-the oral microbiome-is a well-studied microbial reservoir. Because many oral cavity cancer surgeries involve violation of oral mucosa and the spillage of the oral microbiome into normally sterile areas (e.g. the neck), variance in oral microbiome composition and function could underly differences in infectious complications. The goal of this perspective is to highlight 1) this knowledge gap and 2) opportunities for studies in this domain. The implication of this line of thought is that the identification of oral microbial dysbiosis in patients undergoing surgery for oral cavity cancer could lead to targeted pre-operative therapeutic interventions, decreased infectious complications, and improved patient outcomes.

Artificial intelligence-based epigenomic, transcriptomic and histologic signatures of tobacco use in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) biomarker studies rarely employ multi-omic biomarker strategies and pertinent clinicopathologic characteristics to predict mortality. In this study we determine for the first time a combined epigenetic, gene expression, and histology signature that differentiates between patients with different tobacco use history (heavy tobacco use with ≥10 pack years vs. no tobacco use). Using The Cancer Genome Atlas (TCGA) cohort (n = 257) and an internal cohort (n = 40), we identify 3 epigenetic markers (GPR15, GNG12, GDNF) and 13 expression markers (IGHA2, SCG5, RPL3L, NTRK1, CD96, BMP6, TFPI2, EFEMP2, RYR3, DMTN, GPD2, BAALC, and FMO3), which are dysregulated in OSCC patients who were never smokers vs. those who have a ≥ 10 pack year history. While mortality risk prediction based on smoking status and clinicopathologic covariates alone is inaccurate (c-statistic = 0.57), the combined epigenetic/expression and histologic signature has a c-statistic = 0.9409 in predicting 5-year mortality in OSCC patients.

Perineural invasion is associated with function-evoked pain and altered extracellular matrix in patients with head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is painful, and perineural invasion (PNI) has been associated with worst pain. Pain due to HNSCC is diverse and may vary based on clinicopathological factors. This study aims to characterize different pain patterns linked with PNI, its influence on daily functioning, and gain insights into molecular changes and pathways associated with PNI-related pain in HNSCC patients. We conducted a cross-sectional study across three medical centers (n=114), assessing pain phenotypes and their impact on daily functioning using two self-reported pain questionnaires, given to patients prior to their cancer surgery. Furthermore, we conducted RNA-seq analysis utilizing the TCGA dataset of HNSCC tumor from patients (n=192) to identify genes relevant to both PNI and pain. Upon adjusting for demographic and clinicopathological variables using linear regression models, we found that PNI independently predicted function-evoked pain according to the UCSF Oral Cancer Pain Questionnaire, as well as the worst pain intensity reported in the Brief Pain Inventory. Distinct pain patterns were observed to be associated with daily activities in varying manners. Our molecular analyses revealed significant disruptions in pathways associated with extracellular matrix (ECM) structure and organization. The top differentially expressed genes linked to the ECM are implicated in cancer development, pain, and neurodegenerative diseases. Our data underscore the importance of properly categorizing pain phenotypes in future studies aiming to uncover mechanistic underpinnings of pain. Additionally, we have compiled a list of genes of interest that could serve as targets for both cancer and cancer pain management. PERSPECTIVE: PNI independently predicts function-evoked pain. Different pain phenotypes affect daily activities differently. We identified a list of candidate genes involved in extracellular matrix structure and function that can be targeted for both cancer and cancer pain control.

Stimulator of Interferon Genes Pathway Activation through the Controlled Release of STINGel Mediates Analgesia and Anti-Cancer Effects in Oral Squamous Cell Carcinoma.

Oral squamous cell carcinoma (OSCC) presents significant treatment challenges due to its poor survival and intense pain at the primary cancer site. Cancer pain is debilitating, contributes to diminished quality of life, and causes opioid tolerance. The stimulator of interferon genes (STING) agonism has been investigated as an anti-cancer strategy. We have developed STINGel, an extended-release formulation that prolongs the availability of STING agonists, which has demonstrated an enhanced anti-tumor effect in OSCC compared to STING agonist injection. This study investigates the impact of intra-tumoral STINGel on OSCC-induced pain using two separate OSCC models and nociceptive behavioral assays. Intra-tumoral STINGel significantly reduced mechanical allodynia in the orofacial cancer model and alleviated thermal and mechanical hyperalgesia in the hind paw model. To determine the cellular signaling cascade contributing to the antinociceptive effect, we performed an in-depth analysis of immune cell populations via single-cell RNA-seq. We demonstrated an increase in M1-like macrophages and N1-like neutrophils after STINGel treatment. The identified regulatory pathways controlled immune response activation, myeloid cell differentiation, and cytoplasmic translation. Functional pathway analysis demonstrated the suppression of translation at neuron synapses and the negative regulation of neuron projection development in M2-like macrophages after STINGel treatment. Importantly, STINGel treatment upregulated TGF-ß pathway signaling between various cell populations and peripheral nervous system (PNS) macrophages and enhanced TGF-ß signaling within the PNS itself. Overall, this study sheds light on the mechanisms underlying STINGel-mediated antinociception and anti-tumorigenic impact.

Microvascular reconstruction of medication related osteonecrosis of the head and neck.

BACKGROUND: Medication related osteonecrosis of the jaw (MRONJ) requiring free flap (FF) reconstruction is uncommon with limited reported findings. METHODS: Multicenter, retrospective case series of 49 consecutive adult patients presenting with advanced MRONJ requiring FF reconstruction from 2010 to 2022. Perioperative complications and outcomes were analyzed. RESULTS: Eighty-two percent (n = 40) of cases were of the mandible and 18% (n = 9) were of the maxilla. The mean follow-up was 15 months (±19.6). The majority of FF survived (96%, n = 47). FF reconstructions of the maxilla were more likely to require postoperative debridement (56%, 95% CI [27, 81%] vs. 15%, 95% CI [7, 25%], p = 0.008) or develop intraoral bone exposure (56%, 95% CI [27, 81%] vs. 18%, 95% CI [9, 27%], p = 0.02). Most patients (71%, n = 35) received preoperative antibiotics which was associated with a higher rate of FF survival (100% vs. 86%, 95% CI [60, 96%], p = 0.02) and fewer complications. CONCLUSIONS: Patients undergoing FF reconstruction for MRONJ do well with high rates of FF success. MRONJ of the maxilla have a higher rate of some complications. Preoperative antibiotics correlated with higher FF survival and fewer postoperative complications.

Outcomes of Head and Neck Free Tissue Transfer in Renal Failure Patients.

OBJECTIVE: To assess if there is increased risk of free flap failure in renal failure patients undergoing head and neck reconstruction. We seek to primarily assess free flap outcomes based on stages of chronic kidney disease (CKD) and secondarily determine increased risk for postoperative complications. METHODS: Retrospective chart review was performed at five tertiary care centers. Patients were identified that had undergone microvascular free flap reconstruction of the head and neck with diagnosis of renal failure, classified as Stage 3 CKD or higher. Demographic data was collected. Outcomes in the postoperative period were examined. RESULTS: Seventy-three patients met inclusion criteria. The average patient age was 69 years with a male predominance (n = 48). The majority of patients had CKD Stage 3 (n = 52). Overall flap failure rate was 12.33% (n = 9, CKD stage 3 = 7.69%, CKD stage 4 = 30%, CKD stage 5 = 18%). There was an increased risk of flap failure on multivariate analysis for CKD stage 4/5 patients when compared to CKD 3 patients (p = 0.0095). When compared to matched controls, there was an increased risk of flap failure in CKD patients (p = 0.01) as well as an increased risk of overall complications (p < 0.0001). CONCLUSIONS: Patients with CKD undergoing head and neck reconstruction are at a higher risk of flap failure and overall complications. When comparing CKD stages there may be increased risk of flap failure in later stages of CKD compared to CKD 3. Appropriate patient counseling is recommended pre-operatively in this patient population with consideration for regional flaps in the appropriate patient. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:688-694, 2024.

Oncologic Safety of Close Margins in Patients With Low- to Intermediate-Grade Major Salivary Gland Carcinoma.

Importance: Postoperative radiation therapy for close surgical margins in low- to intermediate-grade salivary carcinomas lacks multi-institutional supportive evidence. Objective: To evaluate the oncologic outcomes for low- and intermediate-grade salivary carcinomas with close and positive margins. Design, Setting, and Participants: The American Head and Neck Society Salivary Gland Section conducted a retrospective cohort study from 2010 to 2019 at 41 centers. Margins were classified as R0 (negative), R1 (microscopically positive), or R2 (macroscopically positive). R0 margins were subclassified into clear (>1 mm) or close (≤1 mm). Data analysis was performed from June to October 2023. Main Outcomes and Measures: Main outcomes were risk factors for local recurrence. Results: A total of 865 patients (median [IQR] age at surgery, 56 [43-66] years; 553 female individuals [64%] and 312 male individuals [36%]) were included. Of these, 801 (93%) had parotid carcinoma and 64 (7%) had submandibular gland carcinoma, and 748 (86%) had low-grade tumors and 117 (14%) had intermediate-grade tumors, with the following surgical margins: R0 in 673 (78%), R1 in 168 (19%), and R2 in 24 (3%). Close margins were found in 395 of 499 patients with R0 margins (79%), for whom margin distances were measured. A total of 305 patients (35%) underwent postoperative radiation therapy. Of all 865 patients, 35 (4%) had local recurrence with a median (IQR) follow-up of 35.3 (13.9-59.1) months. In patients with close margins as the sole risk factor for recurrence, the local recurrence rates were similar between those who underwent postoperative radiation therapy (0 of 46) or observation (4 of 165 [2%]). Patients with clear margins (n = 104) had no recurrences. The local recurrence rate in patients with R1 or R2 margins was better in those irradiated (2 of 128 [2%]) compared to observed (13 of 64 [20%]) (hazard ratio [HR], 0.05; 95% CI, 0.01-0.24). Multivariable analysis for local recurrence found the following independent factors: age at diagnosis (HR for a 10-year increase in age, 1.33; 95% CI, 1.06-1.67), R1 vs R0 (HR, 5.21; 95% CI, 2.58-10.54), lymphovascular invasion (HR, 4.47; 95% CI, 1.43-13.99), and postoperative radiation therapy (HR, 0.10; 95% CI, 0.04-0.29). The 3-year local recurrence-free survivals for the study population were 96% vs 97% in the close margin group. Conclusions and Relevance: In this cohort study of patients with low- and intermediate-grade major salivary gland carcinoma, postoperative radiation therapy for positive margins was associated with decreased risk of local recurrence. In isolation from other risk factors for local recurrence, select patients with close surgical margins (≤1 mm) may safely be considered for observation.

Panitumumab-IRDye800 Improves Laryngeal Tumor Mapping During Transoral Laser Microsurgery.

Transoral laser microsurgery represents the primary surgical modality for early laryngeal cancers with oncologic outcomes equivalent to radiotherapy. Accurate tumor mapping and margin assessment can be difficult, however, particularly during piecemeal or ablative resections, and for tumors with a wider geographic footprint. Tumor-targeted fluorescence-guided surgery in patients with head and neck cancer has empirically improved tumor and margin identification; this case details, for the first time, a fluorescence-guided surgical resection of a T2N0M0 transglottic tumor using panitumumab-IRDye800, an epidermal growth factor receptor monoclonal antibody covalently linked to near-infrared (NIR) dye. Laryngoscope, 134:1837-1841, 2024.

Microvascular Free Flap Outcomes in Maxillectomy Defects from Invasive Fungal Sinusitis.

OBJECTIVES: Microvascular free tissue transfer is routinely used for reconstructing midface defects in patients with malignancy, however, studies regarding reconstructive outcomes in invasive fungal sinusitis (IFS) are lacking. We aim to describe outcomes of free flap reconstruction for IFS defects, determine the optimal time to perform reconstruction, and if anti-fungal medications or other risk factors of an immunocompromised patient population affect reconstructive outcomes. METHODS: Retrospective review of reconstruction for IFS (2010-2022). Age, BMI, hemoglobin A1c, number of surgical debridements, and interval from the last debridement to reconstruction were compared between patients with delayed wound healing versus those without. Predictor variables for delayed wound healing and the effect of time on free flap reconstruction were analyzed. RESULTS: Twenty-seven patients underwent free flap reconstruction for IFS. Three patients were immunocompromised from leukemia and 21 had diabetes mellitus (DM). Patients underwent an average of four surgical debridements for treatment of IFS. The interval from the last IFS debridement to flap reconstruction was 5.58 months (±5.5). Seven flaps (25.9%) had delayed wound healing. A shorter interval of less than 2 months between the last debridement for IFS and reconstructive free flap procedure was associated with delayed wound healing (Fisher Exact Test p = 0.0062). Other factors including DM, BMI, HgA1c, and bone reconstruction were not associated with delayed wound healing. CONCLUSION: Patients with maxillectomy defects from IFS can undergo microvascular-free flap reconstruction with good outcomes while on anti-fungal medication. Early reconstruction in the first 2 months after the last IFS debridement is associated with delayed wound healing. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:1642-1647, 2024.

Free Flap Outcomes for Head and Neck Surgery in Patients with COVID-19.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) affects the vascular system, subjecting patients to a hypercoagulable state. This is of particular concern for the success of microvascular free flap reconstruction. This study aims to report head and neck free flap complications in patients with COVID-19 during the perioperative period. We believe these patients are more likely to experience flap complications given the hypercoagulable state. METHODS: This is a multi-institutional retrospective case series of patients infected with COVID-19 during the perioperative period for head and neck free flap reconstruction from March 2020 to January 2022. RESULTS: Data was collected on 40 patients from 14 institutions. Twenty-one patients (52.5%) had a positive COVID-19 test within 10 days before surgery and 7 days after surgery. The remaining patients had a positive test earlier than 10 days before surgery. A positive test caused a delay in surgery for 16 patients (40.0%) with an average delay of 44.7 days (9-198 days). Two free flap complications (5.0%) occurred with no free flap deaths. Four patients (10.0%) had surgical complications and 10 patients had medical complications (25.0%). Five patients (12.5%) suffered from postoperative COVID-19 pneumonia. Three deaths were COVID-19-related and one from cancer recurrence during the study period. CONCLUSION: Despite the heightened risk of coagulopathy in COVID-19 patients, head and neck free flap reconstructions in patients with COVID-19 are not at higher risk for free flap complications. However, these patients are at increased risk of medical complications. LEVEL OF EVIDENCE: 4 Laryngoscope, 2023.

Effect of Perioperative Antithrombotics on Postoperative Transfusion and Hematoma in Head and Neck Free Flaps.

Objective: To explore if antiplatelet or anticoagulant therapy increases the risk of transfusion requirement or postoperative hematoma formation in patients undergoing microvascular reconstruction for head and neck defects. Study Design: Retrospective cohort study. Setting: Departments of Otolaryngology-Head and Neck Surgery at the University of Alabama at Birmingham, the University of Colorado, and the University of California Irvine. Methods: A multi-institutional, retrospective review on microvascular reconstruction of the head and neck between August 2013 to July 2021. Perioperative antithrombotic data were collected to examine predictors of postoperative transfusion and hematoma. Results: A total of 843 free flaps were performed. Preoperative hemoglobin, hematocrit, operative time, and flap type were positive predictors of postoperative transfusion in both bivariate (P < .0001) and multivariate analyses (P < .0001). However, neither anticoagulation nor antiplatelet therapy were predictive of postoperative transfusion rates and hematoma formation. Conclusion: Antithrombotic regimens do not increase the risk of postoperative transfusion or hematoma in head and neck microvascular reconstruction. Based on this limited data, perioperative antithrombotic regimens can be considered in patients who may otherwise be at risk for these postoperative complications.

Clinical outcomes following intraoperative pedicle disruption in fibula free flaps.

OBJECTIVES: Iatrogenic injury of the fibula free flap pedicle is rare. Postoperative flap survival and reconstructive outcomes following intraoperative pedicle severance are unknown. This study assesses free flap outcomes following accidental severance of the peroneal vessels. METHODS: Multi-institutional retrospective chart review from 2000 to 2020. RESULTS: Of 2975 harvested fibula free flaps, 26 had a history of pedicle severance during surgical reconstruction. Reasons for intraoperative pedicle severance included transection during muscular dissection 10/26 (39%), accidental severance with the bone saw 12/26 (46%), and other 4/26 (15.6%). The surgeon responsible for pedicle severance included residents 5/26 (19%), fellows 10/26 (39%), attendings 10/26 (39%), and unknown 1/26 (3.9%). The pedicle artery and vein were severed 10/26 (39%), artery 8/26 (31%), and vein 8/26 (31%). Truncated pedicle vessels were used 3/26 (11.7%), intraoperative anastomoses were performed 23/26 (89%). Postoperative revision in the OR within 7 days of surgery was required 6/26 (23%); 4 flaps were salvaged and 2 flaps failed, both arterial thrombosis. Flap failure was attributed to vascular thrombosis. Long-term flap survival and successful reconstructions were reported 24/26 (92%). CONCLUSION: Accidental severance of fibula free flap pedicle vessels can be corrected with intraoperative repair, without affecting long-term flap survival or reconstructive outcomes. Protecting the flap vessels while using the bone saw and during intramuscular dissection prevents accidental severance.

Determination of Flap Survival Isolated From Wound Bed Vasculature Using a Murine Axial Flap Model.

Background: Axial pattern flaps are a common reconstructive option following resection of soft tissue malignancies. We determine the early dependence of an axial flap on wound bed vasculature by isolating the underlying wound bed and depriving contact with the overlying flap. Materials and Methods: Mice were divided into 5 groups: No silicone (n = 7), silicone in the proximal 50% of the wound bed (n = 8), silicone in the distal 50% of the wound bed (n = 5), silicone over the full length of the wound bed with pedicle preservation (n = 5), and silicone over the full length of the wound bed with pedicle sacrifice (n = 5). The pedicle was the lateral thoracic artery. Daily photographs were taken, and the percent of viable flap was determined using ImageJ© software (public domain JAVA image processing program, National Institute of Health, Bethesda, MA). Percent flap viability for each group was compared to the no silicone group, which acted as the reference. Results: Mean differences in percent flap necrotic area (with 95% confidence interval) compared to the no silicone group were -0.15% (-15.09 to 14.09), 2.07% (-5.26 to 9.39), 2.98% (-10.98 to 16.94), and 14.21% (0.48 to 27.94) for the full-length silicone with preserved pedicle, proximal silicone, distal silicone, and full-length silicone with sacrificed pedicle groups, respectively. The full-length silicone with sacrificed pedicle group had a significant difference in flap viability (P = .045) compared to the no silicone group. Conclusion: We investigate the role of the wound bed vasculature in a murine axial flap model and demonstrate that the wound bed vasculature is not essential for early distal flap survival.

Effect of Perioperative Antithrombotics on Head and Neck Microvascular Free Flap Survival After Anastomotic Revision.

OBJECTIVE: To determine if antithrombotic therapy improves head and neck microvascular free flap survival following anastomotic revision. STUDY DESIGN: A retrospective review of all patients with microvascular free tissue transfer to the head and neck between August 2013 and July 2021. SETTING: Otolaryngology-Head and Neck Surgery Departments at University of Alabama at Birmingham, University of Colorado, and University of California Irvine. METHODS: Perioperative use of anticoagulation, antiplatelets, intraoperative heparin bolus, tissue plasminogen activator (tPA) and vasopressor use, and leech therapy were collected plus microvascular free flap outcomes. The primary endpoint was free flap failure. Analyses of free flaps that underwent anastomotic revision with or without thrombectomy were performed. RESULTS: A total of 843 microvascular free flaps were included. The overall rate of flap failure was 4.0% (n = 34). The overall rate of pedicle anastomosis revision (artery, vein, or both) was 5.0% (n = 42) with a failure rate of 47.6% (n = 20) after revision. Anastomotic revision significantly increased the risk of flap failure (odds ratio [OR] 52.68, 95% confidence interval [CI] [23.90, 121.1], p < .0001) especially when both the artery and vein were revised (OR 9.425, 95% CI [2.117, 52.33], p = .005). Free flap failure after the anastomotic revision was not affected by postoperative antiplatelet therapy, postoperative prophylactic anticoagulation, intraoperative heparin bolus, tPA, and therapeutic anticoagulation regardless of which vessels were revised and if a thrombus was identified. CONCLUSION: In cases of microvascular free tissue transfer pedicle anastomotic revision, the use of antithrombotic therapy does not appear to significantly change free flap survival outcomes.

Post-operative Outcomes in Pediatric Patients Following Facial Reconstruction With Fibula Free Flaps.

EDUCATIONAL OBJECTIVE: Assess outcomes of pediatric facial reconstruction with fibula free flaps. OBJECTIVES: Free flap reconstruction of complex maxillofacial defects in pediatric patients is rare. Post-operative complications, donor site morbidity, impact on craniofacial growth, and oro-dental rehabilitation are unknown. Our study assesses the outcomes of pediatric maxillofacial reconstruction with composite fibula free flaps. STUDY DESIGN: Retrospective chart review. METHODS: Multi-institutional retrospective chart review from 2000 to 2020 on pediatric patients undergoing maxillomandibular reconstruction with fibula free flaps. RESULTS: Eighty-seven patients underwent 89 surgeries; 5 maxillary and 84 mandibular defects. Median age: 12 years. Defects were acquired following resection of sarcoma/carcinoma 44% or benign tumors 50%. 73% of cases had immediate free flap reconstruction. Closing osteotomies were reported in 74%; 1 in 40%, 2 in 27%, and more than 2 in 6.7%. Hardware was used in 98% and removed in 25%. 9.2% demonstrated long-term hardware exposure, greater than 3 months following reconstruction. Short-term complications: wound infection 6.7%, flap salvage/failure 2.2%, fistula 1.1%, and compromised craniofacial growth: 23%. Two patients developed trismus. Long-term fibula donor site complications: hypertrophic scarring: 3.4%, dysesthesia: 1.1%, and long-term gait abnormality: 1.1%. Dental rehabilitation was performed in 33%. Post-operative speech outcomes showed 94% with fully intelligible speech. CONCLUSION: Pediatric maxillary and mandible defects repaired with fibula free flaps demonstrated complication rates comparable to the adult free flap population. Long-term follow-up did not demonstrate adverse outcomes for craniofacial growth. Hardware for flap retention was utilized and remained in place with minimal exposure. Post-operative gait abnormality is rare. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:302-306, 2023.

Evaluating contralateral neck failure in patients with lateralized OPSCC treated with transoral robotic surgery and neck management based on pre-operative SPECT-CT lymphatic mapping.

BACKGROUND: Risk of contralateral nodal metastases in oropharyngeal squamous cell carcinoma (OPSCC) is relatively low, however, many OPSCC patients receive bilateral neck treatment. This study evaluates the oncological outcomes with management of the contralateral cN0 neck based on lymphatic mapping with single photon emission computed tomography (SPECT-CT). METHODS: Retrospective evaluation of patients with lateralized cT1-2 and contralateral cN0 OPSCC treated with primary surgery between December 2017 and October 2019. All patients underwent pre-operative lymphatic mapping using SPECT-CT. Clinical parameters including demographics, tumor characteristics and oncological outcomes were recorded. RESULTS: Thirteen patients underwent primary site resection with transoral robotic surgery (TORS) and ipsilateral neck dissection with or without adjuvant therapy. Twelve patients (92.3%) had ipsilateral drainage on SPECT-CT, whereas 1 (7.7%) patient had bilateral neck lymphatic drainage. Four patients (30.8%) underwent post-operative radiation therapy (PORT). Three patients with unilateral drainage on SPECT-CT underwent PORT with unilateral neck irradiation, and 1 patient with bilateral drainage underwent PORT with bilateral neck irradiation. Seven (53.8%) patients were staged as pT1, 6 (46.2%) patients as pT2, 6 (46.2%) patients were pN0, 3 (23.1%) patients were pN1, 1 (7.7%) patient was pN2a for and 3 (23.1%) patients were N2b. The median distance of the tumor from midline was 1.05 cm (0.0-1.58). Primary sites included tonsil (n = 10, 76.9%) and tongue base (n = 3, 23.1%). The median follow-up time was 15.4 months. All patients were disease free at the latest follow-up with no contralateral neck failures. CONCLUSIONS: Pre-operative mapping of lymphatic drainage in early stage OPSCC with SPECT-CT is a promising tool which can reduce treatment to the contralateral neck potentially without compromising oncological outcomes.

Neurotrophin Pathway Receptors NGFR and TrkA Control Perineural Invasion, Metastasis, and Pain in Oral Cancer.

Oral squamous cell carcinoma (OSCC) patients suffer from poor survival due to metastasis or locoregional recurrence, processes that are both facilitated by perineural invasion (PNI). OSCC has higher rates of PNI than other cancer subtypes, with PNI present in 80% of tumors. Despite the impact of PNI on oral cancer prognosis and pain, little is known about the genes that drive PNI, which in turn drive pain, invasion, and metastasis. In this study, clinical data, preclinical, and in vitro models are leveraged to elucidate the role of neurotrophins in OSCC metastasis, PNI, and pain. The expression data in OSCC patients with metastasis, PNI, or pain demonstrate dysregulation of neurotrophin genes. TrkA and nerve growth factor receptor (NGFR) are focused, two receptors that are activated by NGF, a neurotrophin expressed at high levels in OSCC. It is demonstrated that targeted knockdown of these two receptors inhibits proliferation and invasion in an in vitro and preclinical model of OSCC, and metastasis, PNI, and pain. It is further determined that TrkA knockdown alone inhibits thermal hyperalgesia, whereas NGFR knockdown alone inhibits mechanical allodynia. Collectively the results highlight the ability of OSCC to co-opt different components of the neurotrophin pathway in metastasis, PNI, and pain.

Hyperintensity of integrin-targeted fluorescence agent IntegriSense750 accurately predicts flap necrosis compared to Indocyanine green.

BACKGROUND: Flap necrosis is a feared complication of reconstructive surgery. Current methods of prediction using Indocyanine green (ICG) lack specificity. IntegriSense750 is a fluorescence agent that binds sites of vascular remodeling. We hypothesized that IntegriSense750 better predicts flap compromise compared to ICG. METHODS: Fifteen mice underwent lateral thoracic artery axial flap harvest. Mice received an injection of ICG (n = 7) or IntegriSense750 (n = 8) daily from postoperative days (POD) 0-3 and were imaged daily. Mean signal-to-background ratios quantified the change in fluorescence as necrosis progressed. RESULTS: Mean signal-to-background ratio was significantly higher for IntegriSense750 compared to ICG on POD0 (1.47 ± 0.17 vs. 0.86 ± 0.21, p = 0.01) and daily through POD3 (2.12 ± 0.70 vs. 0.96 ± 0.29, p < 0.001). CONCLUSIONS: IntegriSense750 demonstrates increased signal-to-background ratio at areas of flap distress compared to ICG which may increase identification of flap necrosis and improve patient outcomes.

Impact of preoperative and intraoperative management on outcomes in osteoradionecrosis requiring free flap reconstruction.

BACKGROUND: Perioperative management of advanced osteoradionecrosis of the head and neck requiring free flap (FF) reconstruction varies. Our objectives included assessment of practice patterns and outcomes. METHODS: Multi-institutional, retrospective review of FF reconstruction for head and neck osteoradionecrosis (n = 260). RESULTS: Administration of preoperative antibiotics did not correlate with reduction in postoperative complications. Preoperative alcohol use correlated with higher rates of hardware exposure (p = 0.03) and 30-day readmission (p = 0.04). Patients with FF compromise had higher TSH (p = 0.04) and lower albumin levels (p = 0.005). Prealbumin levels were lower in patients who required neck washouts (p = 0.02) or a second FF (p = 0.03). TSH levels were higher in patients undergoing postoperative debridement (p = 0.03) or local flap procedures (p = 0.04). CONCLUSION: Malnutrition, hypothyroidism, and substance abuse correlated with a higher incidence of postoperative wound complications in patients undergoing FF reconstruction for advanced osteoradionecrosis. Preoperative antibiotics use did not correlate with a reduction in postoperative wound complications.