5-Aminolevulinic Acid Fluorescence-Guided Surgery in Head and Neck Squamous Cell Carcinoma.

OBJECTIVES: To determine the utility of 5-aminolevulinic acid (5-ALA) fluorescence for resection of head and neck carcinoma. METHODS: In this prospective pilot trial, 5-ALA was administered as an oral suspension 3-5 h prior to induction of anesthesia for resection of head and neck squamous cell carcinoma (HNSCC). Following resection, 405 nm blue light was applied, and fluorescence of the tumor as well as the surgical bed was recorded. Specimen fluorescence intensity was graded categorically as none (score = 0), mild (1), moderate (2), or robust (3) by the operating surgeon intraoperatively and corroborated with final pathologic diagnosis. RESULTS: Seven patients underwent resection with 5-ALA. Five (83%) were male with an age range of 33-82 years (mean = 60). Sites included nasal cavity (n = 3), oral cavity (n = 3), and the larynx (n = 1). All specimens demonstrated robust fluorescence when 5-ALA was administered 3-5 h preoperatively. 5-ALA fluorescence predicted the presence of perineural invasion, a positive margin, and metastatic lymphadenopathy. Two patients had acute photosensitivity reactions, and one patient had a temporary elevation of hepatic enzymes. CONCLUSIONS: 5-ALA induces robust intraoperative fluorescence of HNSCC, capable of demonstrating a positive margin, perineural invasion, and metastatic nodal disease. Although no conclusions are there about the safety of this drug in the head and neck cancer population, our study parallels the extensive safety data in the neurosurgical literature. Future applications may include intraoperative assessment of margin status, diagnostic accuracy, and impacts on survival. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:741-748, 2024.

Gabapentin and postoperative pain and opioid consumption: A double-blind randomized controlled trial of perioperative pain management for sinus surgery.

BACKGROUND: The link between post-operative narcotic prescription and opioid misuse has spurred a nationwide effort to reduce perioperative opioid use. Previous work has suggested that perioperative gabapentin may reduce post-operative pain and opioid consumption across different procedures, although the optimal regimen remains to be defined. METHODS: Chronic rhinosinusitis (CRS) patients undergoing functional endoscopic sinus surgery (FESS) with or without septoplasty were randomized to receive a 7-day pre- and post-operative course of placebo or gabapentin, starting at 300 mg daily and titrated to 300 mg three times daily, in a double-blind fashion. Primary endpoint was pain level using a validated visual analog scale (VAS). Secondary endpoints included post-operative opioid consumption and side effects, as well as modified Lund-Kennedy endoscopy, Lund-Mackay, and SNOT-22 scores. RESULTS: Analysis of 35 patients (20 gabapentin, 15 control) showed no significant difference in mean postoperative VAS (p = 0.18) or postoperative opioid consumption between the placebo and gabapentin groups (2.3 and 4.8 oxycodone tablets respectively, p = 0.18). 15 of 35 patients did not require any post-operative oxycodone tablets, and only two patients required more than six tablets. CONCLUSION: Preliminary results show no significant change in pain after FESS with or without septoplasty in patients taking 7-day pre- and post-operative gabapentin versus placebo. Results also showed no significant difference in opioid consumption between the treatment and placebo groups. Post-operative pain scores and opioid requirements are both quite low following FESS. Many patients do not need opioids at all, suggesting that routine initial post-operative opioid prescriptions can be limited accordingly.

Cell volume expansion and local contractility drive collective invasion of the basement membrane in breast cancer.

Breast cancer becomes invasive when carcinoma cells invade through the basement membrane (BM)-a nanoporous layer of matrix that physically separates the primary tumour from the stroma. Single cells can invade through nanoporous three-dimensional matrices due to protease-mediated degradation or force-mediated widening of pores via invadopodial protrusions. However, how multiple cells collectively invade through the physiological BM, as they do during breast cancer progression, remains unclear. Here we developed a three-dimensional in vitro model of collective invasion of the BM during breast cancer. We show that cells utilize both proteases and forces-but not invadopodia-to breach the BM. Forces are generated from a combination of global cell volume expansion, which stretches the BM, and local contractile forces that act in the plane of the BM to breach it, allowing invasion. These results uncover a mechanism by which cells collectively interact to overcome a critical barrier to metastasis.

SLC12A9 is a lysosome-detoxifying ammonium - chloride co-transporter.

Ammonia is a ubiquitous, toxic by-product of cell metabolism. Its high membrane permeability and proton affinity causes ammonia to accumulate inside acidic lysosomes in its poorly membrane-permeant form: ammonium (NH 4 + ). Ammonium buildup compromises lysosomal function, suggesting the existence of mechanisms that protect cells from ammonium toxicity. Here, we identified SLC12A9 as a lysosomal ammonium exporter that preserves lysosomal homeostasis. SLC12A9 knockout cells showed grossly enlarged lysosomes and elevated ammonium content. These phenotypes were reversed upon removal of the metabolic source of ammonium or dissipation of the lysosomal pH gradient. Lysosomal chloride increased in SLC12A9 knockout cells and chloride binding by SLC12A9 was required for ammonium transport. Our data indicate that SLC12A9 is a chloride-driven ammonium co-transporter that is central in an unappreciated, fundamental mechanism of lysosomal physiology that may have special relevance in tissues with elevated ammonia, such as tumors.

Omega-3 Fatty Acid Supplementation for the Treatment of Persistent COVID-Related Olfactory Dysfunction.

OBJECTIVE: To evaluate the efficacy of omega-3 fatty acid (O3FA) supplementation in the treatment of COVID-related olfactory dysfunction (OD). METHODS: Patients with laboratory-confirmed or clinically-suspected COVID-19 infection and new-onset OD from August 2020 to November 2021 were prospectively recruited. Patients with quantitative OD, defined as a brief smell identification test (BSIT) score of 9 or less, were eligible for study inclusion. The experimental group received 2 g of O3FA supplementation, while the control group received an identical placebo to be taken daily for 6 weeks. The primary outcome was a change in BSIT score between the initial and 6-week follow-up tests. RESULTS: One hundred and seventeen patients were included in the analysis, including 57 patients in the O3FA group and 60 in the placebo group. O3FA group patients demonstrated a mean BSIT improvement of 1.12 ± 1.99 compared to 0.68 ± 1.86 in the placebo group (p = 0.221). Seventy-seven patients, 42 within the O3FA group and 35 in the placebo group, completed a follow-up BSIT survey at an average of 717.8 days from study onset. At long-term follow-up, there was an average BSIT score improvement of 1.72 within the O3FA group compared to 1.76 within the placebo group (p = 0.948). CONCLUSION: Among patients with persistent COVID-related OD, our study showed no clear evidence of relative short-term or long-term olfactory recovery among patients receiving high doses of O3FA supplementation.

Deterministic evolution and stringent selection during preneoplasia.

The earliest events during human tumour initiation, although poorly characterized, may hold clues to malignancy detection and prevention1. Here we model occult preneoplasia by biallelic inactivation of TP53, a common early event in gastric cancer, in human gastric organoids. Causal relationships between this initiating genetic lesion and resulting phenotypes were established using experimental evolution in multiple clonally derived cultures over 2 years. TP53 loss elicited progressive aneuploidy, including copy number alterations and structural variants prevalent in gastric cancers, with evident preferred orders. Longitudinal single-cell sequencing of TP53-deficient gastric organoids similarly indicates progression towards malignant transcriptional programmes. Moreover, high-throughput lineage tracing with expressed cellular barcodes demonstrates reproducible dynamics whereby initially rare subclones with shared transcriptional programmes repeatedly attain clonal dominance. This powerful platform for experimental evolution exposes stringent selection, clonal interference and a marked degree of phenotypic convergence in premalignant epithelial organoids. These data imply predictability in the earliest stages of tumorigenesis and show evolutionary constraints and barriers to malignant transformation, with implications for earlier detection and interception of aggressive, genome-instable tumours.

Assessing hospitalists' opinions regarding the role of environmental health within the practice of hospital medicine.

BACKGROUND: Environmental health represents the concept that a stable climate and clean environment are fundamental prerequisites for good human health. Despite growing awareness of the impact of climate change more broadly, knowledge of environmental health has not fully entered mainstream medicine in the United States. OBJECTIVE: To understand practicing hospitalists' perspectives regarding the current and future roles of environmental health within the practice of hospital medicine, as well as existing barriers and potential motivators to its further inclusion. METHODS: We conducted virtual focus groups of practicing hospitalists in partnership with the Hospital Medicine Reengineering Network from across the United States. Structured interviews elicited hospitalists' thoughts pertaining to environmental health. Transcripts then underwent descriptive coding to identify and group comments into themes. RESULTS: We conducted three focus groups with a total of 14 physician participants. Four themes emerged: the negative environmental impact of the healthcare system, a lack of prioritization of environmental health within hospital medicine, the potential for expanding environmental health in nonclinical roles including medical education, and the importance of systems-level support. CONCLUSION: Environmental health is felt to be of importance, and while there exist avenues to do better, there is limited understanding of hospitalists' most effective role in making change.

Nocturnal Oxygen Desaturation Index Correlates with Respiratory Depression in Post-Surgical Patients Receiving Opioids - A Post-Hoc Analysis from the Prediction of Opioid-Induced Respiratory Depression in Patients Monitored by Capnography (PRODIGY) Study.

Purpose: Postoperative monitoring of respiratory status on general care wards typically consists of intermittent checks of oxyhemoglobin saturation and respiratory rate, allowing substantial unmonitored time for severe opioid induced respiratory depression (RD) to develop unnoticed. Oxygen desaturation index (ODI) can be computed solely by continuous pulse oximetry monitoring. In this post-hoc analysis, we evaluate whether nocturnal ODI correlates with RD. Patients and Methods: The PRODIGY trial (NCT02811302) was a multinational study conducted where adult patients receiving parenteral opioids on the general care floor were continuously monitored by blinded pulse oximetry and capnography monitoring to detect episodes of RD. An RD episode was defined as: respiratory rate ≤5 breaths/min (bpm) for ≥3 minutes, oxygen saturation (SpO2) ≤85% for ≥3 minutes, end-tidal carbon dioxide (EtCO2) ≤15 or ≥60 mm Hg for ≥3 minutes, apnea episode lasting >30 seconds, or any respiratory opioid-related adverse event. Data were used to calculate nocturnal (00:00 ─ 06:00) ODI4% based on desaturation episodes (4% decrease from mean oxyhemoglobin saturation in the past 120 seconds, lasting ≥10 seconds). Continuous monitoring began after a patient received parenteral opioids, allowing identification of potential RD and ODI4% episodes during opioid therapy. The average number of ODI4% episodes (≥1, ≥5, ≥10, ≥15 episodes/hour) were analyzed. Logistic regression and area under the receiver operating characteristic curve (AUC) were computed. Results: A final cohort of 1072 (out of 1335) patients had sufficient data, with 76% (N=817/1072) having ≥1 episode of ODI4%. Multivariable logistic regression showed that ODI4% was strongly associated with RD, with greater risk for higher ODI4% scores: ≥5 episodes/hour odds ratio 2.59 (95% CI 1.72-3.89, p<0.0001); ≥10 episodes/hour 3.39 (95% CI 1.80-6.39, p=0.0002); ≥15 episodes/hour 4.71 (95% CI 1.93-11.47, p=0.0006).There was no significant association between ODI4% and respiratory adverse events. Conclusion: Nocturnal ODI4% was highly correlated with RD among hospitalized patients receiving parenteral opioids. Patients with a high ODI4%, especially with ≥15 episodes/hour, are more likely to experience RD and should be evaluated for the need of closer monitoring after opioid administration.

Seeking an optimal dose of preoperative corticosteroids in chronic rhinosinusitis with nasal polyposis: A randomized controlled trial.

BACKGROUND: Preoperative corticosteroids have been shown to improve surgical visibility and intraoperative blood loss for chronic rhinosinusitis with nasal polyposis (CRSwNP) patients undergoing endoscopic sinus surgery (ESS). However, there is no consensus on the optimal dosing regimen. METHODS: A randomized, controlled trial was conducted to compare low, medium, and high dose corticosteroids prior to ESS. Patients with CRSwNP refractory to medical management were randomized to low (N = 8), medium (N = 10), or high (N = 5) dosing regimens of corticosteroids prior to ESS. Baseline disease severity was measured with the 22-item Sino-nasal Outcome Test and Lund-Mackay scores. Modified Lund-Kennedy endoscopic scores (MLKES) were measured at baseline and after corticosteroid treatment. Intraoperative parameters were measured including Boezaart surgical visibility score, intraoperative blood loss, and operative time. RESULTS: Medium dose corticosteroids demonstrated a superior surgical visibility score to low dose and comparable results to high dose, but these results were not significant (p = 0.33). No significant difference was observed between groups for total blood loss (p = 0.15), operative time (p = 0.87), or change in MLKES (p = 0.27). CONCLUSIONS: Current recommendations include the use of preoperative corticosteroids in patients with CRSwNP undergoing ESS, but there is no consensus on dose or duration. We did not find a statistically significant difference in surgical field visibility, intraoperative blood loss, or operative time between different dosing regimens. Further studies are needed to evaluate the efficacy of a low-dose preoperative regimen with the goal of reducing cumulative patient exposure to systemic corticosteroids.

Association Between Race and Opioid-Induced Respiratory Depression: An International Post Hoc Analysis of the Prediction of Opioid-induced Respiratory Depression In Patients Monitored by Capnography Trial.

BACKGROUND: Opioid-induced respiratory depression (OIRD) is common on the medical and surgical wards and is associated with increased morbidity and health care costs. While previous studies have investigated risk factors for OIRD, the role of race remains unclear. We aim to investigate the association between race and OIRD occurrence on the medical/surgical ward. METHODS: This is a post hoc analysis of the PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) trial; a prospective multinational observational blinded study of 1335 general ward patients who received parenteral opioids and underwent blinded capnography and oximetry monitoring to identify OIRD episodes. For this study, demographic and perioperative data, including race and comorbidities, were analyzed and assessed for potential associations with OIRD. Univariable χ 2 and Mann-Whitney U tests were used. Stepwise selection of all baseline and demographic characteristics was used in the multivariable logistic regression analysis. RESULTS: A total of 1253 patients had sufficient racial data (317 Asian, 158 Black, 736 White, and 42 other races) for inclusion. The incidence of OIRD was 60% in Asians (N = 190/317), 25% in Blacks (N = 40/158), 43% in Whites (N = 316/736), and 45% (N = 19/42) in other races. Baseline characteristics varied significantly: Asians were older, more opioid naïve, and had higher opioid requirements, while Blacks had higher incidences of heart failure, obesity, and smoking. Stepwise multivariable logistic regression revealed that Asians had increased risk of OIRD compared to Blacks (odds ratio [OR], 2.49; 95% confidence interval [CI], 1.54-4.04; P = .0002) and Whites (OR, 1.38; 95% CI, 1.01-1.87; P = .0432). Whites had a higher risk of OIRD compared to Blacks (OR, 1.81; 95% CI, 1.18-2.78; P = .0067). The model's area under the curve was 0.760 (95% CI, 0.733-0.787), with a Hosmer-Lemeshow goodness-of-fit test P value of .23. CONCLUSIONS: This post hoc analysis of PRODIGY found a novel association between Asian race and increased OIRD incidence. Further study is required to elucidate its underlying mechanisms and develop targeted care pathways to reduce OIRD in susceptible populations.

Modulating the Influenza A Virus-Target Membrane Fusion Interface With Synthetic DNA-Lipid Receptors.

Influenza A virus (IAV) binds to sialylated glycans on the cell membrane before endocytosis and fusion. Cell-surface glycans are highly heterogeneous in length and glycosylation density, which leads to variations in the distance and rigidity with which IAV is held away from the cell membrane. To gain mechanistic insight into how receptor length and rigidity impact the mechanism of IAV entry, we employed synthetic DNA-lipids as highly tunable surrogate receptors. We tethered IAV to target membranes with a panel of DNA-lipids to investigate the effects of the distance and tether flexibility between virions and target membranes on the kinetics of IAV binding and fusion. Tether length and the presence of a flexible linker led to higher rates of IAV binding, while the efficiencies of lipid and content mixing were typically lower for longer and more rigid DNA tethers. For all DNA tether modifications, we found that the rates of IAV lipid and content mixing were unchanged. These results suggest that variations in the interface between IAV and a target membrane do not significantly impact the rate-limiting step of fusion or the low-pH-triggered engagement of viral fusion peptides with the target membrane. However, our results imply that the flexibility of the viral receptor is important for ensuring that hemifusion events are able to successfully proceed to pore formation.

Sinonasal Issues After Maxillectomy With Free Flap Reconstruction: Incidence and Clinical Approach.

OBJECTIVE: To characterize the clinical features associated with sinonasal complaints after maxillectomy with free flap reconstruction as well as propose a screening and treatment algorithm. METHODS: Retrospective review of patients who underwent maxillectomy and free flap reconstruction at a tertiary care center. RESULTS: Fifty-eight patients were included, 25 (43.1%) of them had documented sinonasal complaints postoperatively. Eleven patients subsequently underwent revision surgery for sinonasal complaints. Among the 25 patients with sinonasal complaints, 22 patients (88.0%) had nasal crusting, 17 (68.0%) had nasal obstruction, 12 (48.0%) had rhinorrhea, 9 (36.0%) had facial pain or pressure, and 7 (28.0%) had foul odor. Twenty-two patients (88.0%) had multiple sinonasal complaints. There was a higher incidence of both sinonasal complaints and surgical intervention in patients who underwent adjuvant radiation, but this was not statistically significant (47.7% vs 28.6%, P = .235; 29.4% vs 7.1%, P = .265). CONCLUSIONS: Sinonasal complaints are common following free flap reconstruction for a maxillectomy defect and should be screened for at postoperative visits, with early referral to a rhinologist for consideration of endoscopic sinus surgery. Nonsurgical treatment strategies include large-volume nasal saline irrigations, xylitol irrigations for persistent inflammatory symptoms, and culture-directed antibiotic irrigations for persistent infectious symptoms. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:67-72, 2022.

Inter-cellular CRISPR screens reveal regulators of cancer cell phagocytosis.

Monoclonal antibody therapies targeting tumour antigens drive cancer cell elimination in large part by triggering macrophage phagocytosis of cancer cells1-7. However, cancer cells evade phagocytosis using mechanisms that are incompletely understood. Here we develop a platform for unbiased identification of factors that impede antibody-dependent cellular phagocytosis (ADCP) using complementary genome-wide CRISPR knockout and overexpression screens in both cancer cells and macrophages. In cancer cells, beyond known factors such as CD47, we identify many regulators of susceptibility to ADCP, including the poorly characterized enzyme adipocyte plasma membrane-associated protein (APMAP). We find that loss of APMAP synergizes with tumour antigen-targeting monoclonal antibodies and/or CD47-blocking monoclonal antibodies to drive markedly increased phagocytosis across a wide range of cancer cell types, including those that are otherwise resistant to ADCP. Additionally, we show that APMAP loss synergizes with several different tumour-targeting monoclonal antibodies to inhibit tumour growth in mice. Using genome-wide counterscreens in macrophages, we find that the G-protein-coupled receptor GPR84 mediates enhanced phagocytosis of APMAP-deficient cancer cells. This work reveals a cancer-intrinsic regulator of susceptibility to antibody-driven phagocytosis and, more broadly, expands our knowledge of the mechanisms governing cancer resistance to macrophage phagocytosis.

Single-virus content-mixing assay reveals cholesterol-enhanced influenza membrane fusion efficiency.

To infect a cell, enveloped viruses must first undergo membrane fusion, which proceeds through a hemifusion intermediate, followed by the formation of a fusion pore through which the viral genome is transferred to a target cell. Single-virus fusion studies to elucidate the dynamics of content mixing typically require extensive fluorescent labeling of viral contents. The labeling process must be optimized depending on the virus identity and strain and can potentially be perturbative to viral fusion behavior. Here, we introduce a single-virus assay in which content-labeled vesicles are bound to unlabeled influenza A virus (IAV) to eliminate the problematic step of content-labeling virions. We use fluorescence microscopy to observe individual, pH-triggered content mixing and content-loss events between IAV and target vesicles of varying cholesterol compositions. We show that target membrane cholesterol increases the efficiency of IAV content mixing and decreases the fraction of content-mixing events that result in content loss. These results are consistent with previous findings that cholesterol stabilizes pore formation in IAV entry and limits leakage after pore formation. We also show that content loss due to hemagglutinin fusion peptide engagement with the target membrane is independent of composition. This approach is a promising strategy for studying the single-virus content-mixing kinetics of other enveloped viruses.

Long Term Olfactory Outcomes Following Frontal Sinus Surgery in Chronic Rhinosinusitis.

OBJECTIVES/HYPOTHESIS: No studies have evaluated the impact of the types of frontal sinus surgery (FSS) on objective olfaction scores. This study evaluated olfactory function and quality of life (QOL) in chronic rhinosinusitis (CRS) patients before and after total ethmoidectomy with frontal sinusotomy (FS). STUDY DESIGN: Prospective cohort study. METHODS: A prospective study of adult CRS patients undergoing FSS (Draf 2 or Draf 3 procedures) was conducted at a tertiary care center. Primary outcomes included brief smell identification test (BSIT) and sinonasal outcome test-22 (SNOT-22), which were assessed during preoperative evaluation, 6 to 9 weeks postoperatively, and 12 to 24 weeks postoperatively. Normosmia was defined as BSIT ≥9. Statistical significance was determined using the Wilcoxon signed-rank test with α = .05. RESULTS: Thirty-eight patients followed up 12 to 24 weeks after FSS. The differences between baseline and long-term outcomes for BSIT (6.11 vs. 8.24, P = .00034) and SNOT-22 (55.49 vs. 24.32, P < .00001) scores were found to be statistically significant. Although both subgroups had clinically significant olfactory improvements, only the Draf 2 cohort experienced a statistically significant improvement in olfaction at long-term follow-up. There was no statistically significant change in data from 6 to 9 weeks to 12 to 24 weeks postoperatively. CONCLUSIONS: Patients undergoing total ethmoidectomy with FS demonstrated statistically significant increases in olfaction and QOL at long-term postoperative follow-up. This study demonstrated that FS does not negatively impact the olfactory improvement seen in sinus surgery. The lack of statistically significant changes in these olfactory metrics from short to long-term follow-up suggests that there is no additional negative effect of FSS in the long term. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:2173-2178, 2021.

The value of 68 Gallium-DOTATATE PET/CT in sinonasal neuroendocrine tumor management: A case series.

BACKGROUND: 68 Gallium-DOTATATE (68 Ga-DOTATATE) is a somatostatin analog used as a PET tracer to successfully identify neuroendocrine tumors (NETs). Due to the rarity of sinonasal NETs, there are few recommendations for 68 Ga-DOTATATE imaging in these patients. METHODS: We discussed the impact of 68 Ga-DOTATATE imaging on the management of six sinonasal NET cases and reviewed existing literature. RESULTS: 68 Ga-DOTATATE PET/CT revealed an unknown primary in one case and identified metastatic disease in a primary sinonasal small cell neuroendocrine carcinoma (SNEC) patient missed on conventional imaging. In two esthesioneuroblastoma (ENB) patients, 68 Ga-DOTATATE detected abnormal radiotracer uptake not present on 18F-FDG PET/CT and identified a patient for treatment with 177 Lu-DOTATATE. CONCLUSIONS: This is the one of the first few reports, and the largest series to our knowledge, demonstrating the utility of 68 Ga-DOTATATE imaging for primary sinonasal SNEC and ENB. Further study is required to determine its role in sinonasal NET management.