Intraoperative diagnosis of facial schwannomas: a multicenter summation of clinical experience, preoperative avoidance, and intraoperative management protocol
OBJECTIVE Preoperative differentiation of facial nerve schwannoma (FNS) from vestibular schwannoma (VS) can be challenging, and failure to differentiate between these two pathologies can result in potentially avoidable facial nerve injury. This study presents the combined experience of two high-volume centers in the management of intraoperatively diagnosed FNSs. The authors highlight clinical and imaging features that can distinguish FNS from VS and provide an algorithm to help manage intraoperatively diagnosed FNS. METHODS Operative records of 1484 presumed sporadic VS resections between January 2012 and December 2021 were reviewed, and patients with intraoperatively diagnosed FNSs were identified. Clinical data and preoperative imaging were retrospectively reviewed for features suggestive of FNS, and factors associated with good postoperative facial nerve function (House-Brackmann [HB] grade ≤ 2) were identified. A preoperative imaging protocol for suspected VS and recommendations for surgical decision-making following an intraoperative FNS diagnosis were created. RESULTS Nineteen patients (1.3%) with FNSs were identified. All patients had normal facial motor function preoperatively. In 12 patients (63%), preoperative imaging demonstrated no features suggestive of FNS, with the remainder showing subtle enhancement of the geniculate/labyrinthine facial segment, widening/erosion of the fallopian canal, or multiple tumor nodules in retrospect. Eleven (57.9%) of the 19 patients underwent a retrosigmoid craniotomy, and in the remaining patients, a translabyrinthine (n = 6) or transotic (n = 2) approach was used. Following FNS diagnosis, 6 (32%) of the tumors underwent gross-total resection (GTR) and cable nerve grafting, 6 (32%) underwent subtotal resection (STR) and bony decompression of the meatal facial nerve segment, and 7 (36%) underwent bony decompression only. All patients undergoing subtotal debulking or bony decompression exhibited normal postoperative facial function (HB grade I). At the last clinical follow-up, patients who underwent GTR with a facial nerve graft had HB grade III (3 of 6 patients) or IV facial function. Tumor recurrence/regrowth occurred in 3 patients (16%), all of whom had been treated with either bony decompression or STR. CONCLUSIONS Intraoperative diagnosis of an FNS during a presumed VS resection is rare, but its incidence can be reduced further by maintaining a high index of suspicion and undertaking further imaging in patients with atypical clinical or imaging features. If an intraoperative diagnosis does occur, conservative surgical management with bony decompression of the facial nerve only is recommended, unless there is significant mass effect on surrounding structures.
Development and Performance Of a Multiplex PCR Assay For the Detection of Bacteria in Sterile Body Fluids
Firefighters often complete air management courses (AMC) to assess the ability to tolerate personal protective equipment, appropriately manage the breathing system and assess occupational performance. Little information is known relative to the physiological demands of AMCs, nor how to assess work efficiency in order to characterize occupational performance and evaluate progress. Purpose: To assess the physiological demands of an AMC and examine differences across BMI categories. A secondary aim was to develop an equation to assess work efficiency in firefighters. Methods: Fifty-seven firefighters (Women, n = 4; age: 37.2 ± 8.4 yr.; height: 182.0 ± 6.9 cm; body mass: 90.8 ± 13.1 kg; BMI: 27.8 ± 3.6 kg·m−2) completed an AMC per routine evaluation while wearing a department issued self-contained breathing apparatus and full protective gear. Course completion time, starting pounds per square inch (PSI) on the air cylinder, changes in PSI, and distance traveled were recorded. All firefighters were equipped with a wearable sensor integrated with a triaxial accelerometer and telemetry to assess movement kinematics, heart rate, energy expenditure, and training impulse. The AMC consisted of an initial section involving a hose line advance, rescue (body drag), stair climb, ladder raise, and forcible entry. This section was followed by a repeating loop, which consisted of a stair climb, search, hoist, and recovery walk. Firefighters repeated the course loop until the self-contained breathing apparatus air supply pressure reached 200 PSI, at which time they were instructed to lay down until the PSI reached zero. Results: Average completion time was 22.8 ± 1.4 min, with a mean distance of 1.4 ± 0.3 km and an average velocity of 2.4 ± 1.2 m·s−1. Throughout the AMC, the mean heart rate was 158.7 ± 11.5 bpm equating to 86.8 ± 6.3% of the age-predicted max heart rate and a training impulse of 55 ± 3 AU. Mean energy expenditure was 464 ± 86 kcals and work efficiency was 49.8 ± 14.9 km·PSI−1·s. Regression analysis determined that fat-free mass index (R2 = 0.315; β = −5.069), body fat percentage (R2 = 0.139; β = −0.853), fat-free mass (R2 = 0.176; β = −0.744), weight (R2 = 0.329; β = −0.681), and age (R2 = 0.096; β = −0.571) were significant predictors of work efficiency. Conclusions: The AMC is a highly aerobic task with near-maximal heart rates reached throughout the course. Smaller and leaner individuals achieved a higher degree of work efficiency during the AMC.
Respiratory viruses: New frontiers—a Keystone Symposia report
AbstractRespiratory viruses are a common cause of morbidity and mortality around the world. Viruses like influenza, RSV, and most recently SARS‐CoV‐2 can rapidly spread through a population, causing acute infection and, in vulnerable populations, severe or chronic disease. Developing effective treatment and prevention strategies often becomes a race against ever‐evolving viruses that develop resistance, leaving therapy efficacy either short‐lived or relevant for specific viral strains. On June 29 to July 2, 2022, researchers met for the Keystone symposium “Respiratory Viruses: New Frontiers.” Researchers presented new insights into viral biology and virus–host interactions to understand the mechanisms of disease and identify novel treatment and prevention approaches that are effective, durable, and broad.
Idiopathic ventricular tachycardia (VT) is an important cause of morbidity and less commonly, mortality in patients with structurally normal hearts. Appropriate diagnosis and management are predicated on an understanding of the mechanism, relevant cardiac anatomy, and associated ECG signatures. Catheter ablation is a viable strategy to adequately treat and potentially provide a cure in patients that are intolerant to medications or when these are ineffective. In this review, we discuss special approaches and considerations for effective and safe ablation of VT arising from the right ventricular outflow tract, left ventricular outflow tract, left ventricular fascicles, papillary muscles, and moderator band.
MOUNTAINEER-03: Phase 3 study of tucatinib, trastuzumab, and mFOLFOX6 as first-line treatment in HER2+ metastatic colorectal cancer—Trial in progress.
TPS261 Background: Current standard of care (SOC) for treatment (tx) of metastatic colorectal cancer (mCRC) is multi-agent chemotherapy, w/ or w/o a VEGF- or EGFR-inhibitor. HER2 is a validated clinical target in breast and gastric cancers. HER2 amplification occurs in 3%-5% of patients (pts) w/ mCRC; the rate of HER2 amplification can increase to ~10% in pts w/ RAS/BRAF wild-type mCRC tumors. Tucatinib (TUC), a highly selective, HER2-directed tyrosine kinase inhibitor, is approved in multiple regions for HER2+ metastatic breast cancer and is being investigated in gastrointestinal cancers. MOUNTAINEER (NCT03043313) evaluated the safety and efficacy of TUC and trastuzumab (Tras) in pts w/ tx refractory RAS wild-type, HER2+ mCRC. Results from the primary endpoint analysis showed clinically meaningful activity (confirmed ORR of 38.1% and median DOR of 12.4 months) and demonstrated TUC + Tras was well tolerated with a low discontinuation rate (5.8%) and no deaths due to AEs. MOUNTAINEER-03 will further investigate TUC in combo w/ mFOLFOX and Tras in pts w/ RAS wild-type, HER2+ mCRC. Methods: MOUNTAINEER-03 (NCT05253651) is a global, open label, randomized, phase 3 study for 1L tx of HER2+ and RAS wild-type mCRC. Approximately 400 pts will be randomized 1:1 to the TUC experimental arm (TUC [300 mg PO BID] + Tras + mFOLFOX) or the SOC arm (mFOLFOX alone or in combo w/ either bevacizumab or cetuximab). HER2 status is determined centrally w/ tissue based HER2 immunohistochemistry and in situ hybridization assays. Eligible pts must not have received prior tx in the metastatic setting but may have received adjuvant tx if completed > 6 months prior to enrollment. Pts must be ≥18 years of age w/ an ECOG performance status of ≤1 and RAS wild-type mCRC. Pts w/ treated stable central nervous system metastases are eligible. Randomization is stratified by primary tumor location (left-sided vs other) and liver metastases (presence/absence). Primary endpoint is progression-free survival per RECIST v1.1, assessed by blinded independent central review (BICR). Key secondary endpoints are overall survival and confirmed objective response rate per RECIST v1.1 assessed by BICR. Enrollment is ongoing in the US, w/ global sites planned. Clinical trial information: NCT05253651 .
TMEM161B regulates cerebral cortical gyration, Sonic Hedgehog signaling, and ciliary structure in the developing central nervous system
Sonic hedgehog signaling regulates processes of embryonic development across multiple tissues, yet factors regulating context-specific Shh signaling remain poorly understood. Exome sequencing of families with polymicrogyria (disordered cortical folding) revealed multiple individuals with biallelic deleterious variants in TMEM161B , which encodes a multi-pass transmembrane protein of unknown function. Tmem161b null mice demonstrated holoprosencephaly, craniofacial midline defects, eye defects, and spinal cord patterning changes consistent with impaired Shh signaling, but were without limb defects, suggesting a CNS-specific role of Tmem161b. Tmem161b depletion impaired the response to Smoothened activation in vitro and disrupted cortical histogenesis in vivo in both mouse and ferret models, including leading to abnormal gyration in the ferret model. Tmem161b localizes non-exclusively to the primary cilium, and scanning electron microscopy revealed shortened, dysmorphic, and ballooned ventricular zone cilia in the Tmem161b null mouse, suggesting that the Shh-related phenotypes may reflect ciliary dysfunction. Our data identify TMEM161B as a regulator of cerebral cortical gyration, as involved in primary ciliary structure, as a regulator of Shh signaling, and further implicate Shh signaling in human gyral development.
Abstract PR002: A pilot study of a MUC1 vaccine in current and former smokers at high risk for lung cancer
Abstract Background: Smoking is the most common etiology for lung cancer and smoking cessation does not eliminate the risk. An emerging area of interest for risk reduction is immunoprevention. MUC1 glycoprotein is aberrantly expressed in adenocarcinomas, including lung cancer and their premalignant lesions. MUC1 vaccine in the premalignant or high-risk setting may be effective in halting neoplastic development and progression. Trial design: Through the NCI-funded Cancer Prevention Network (CPN), we conducted a two-center pilot trial to evaluate immunogenicity of the MUC1 vaccine (assessed at 12 weeks), and safety (assessed at up to 24 weeks) in current and former heavy smokers. 87 participants were screened in order to have at least 40 evaluable for baseline and 12-week immunogenicity assessments. Smoking history of ≥30 pack-years and either current (still smoking or quit < 1 year prior to pre-registration) or former smoker (quit 1-15 years prior to pre-registration); ages 55-80 years; ECOG performance status ≤1; CT scan of the chest done ≤ 6 months prior to pre-registration showing either negative findings (no nodules) or solid or part-solid nodules < 6 mm in size (consistent with < 1% probability of malignancy, Lung-RADs Version 1.0). Exclusion criteria were standard for lung cancer screening. Methods: MUC1 peptide plus polyICLC adjuvant (Hiltonol) vaccine was given at week 0, 2 and 10. Blood was collected for safety tests and immune assays pre and 2 weeks post each vaccine, and at week 24. Anti-MUC1 IgG titer was evaluated by ELISA. Based on previous studies of this vaccine, 40 evaluable participants would provide 96% power to detect immune response rate of 15% versus 40%, using a 2-sided test of proportions with type I error rate of 0.05. PBMC were assayed for the presence of regulatory T cells (Treg) and myeloid derived suppressor cells (MDSC) (secondary endpoint). Circulating levels of inflammatory cytokines and hsCRP were evaluated using commercially available tests (exploratory endpoint). AEs and toxicities were monitored for up to 24 weeks from the first vaccine. Results: 87 individuals were screened and 50 registered. 45 completed the study, 26 current and 19 former smokers (time since last smoked: average 7.8 years; 11 months -13 years). The vaccine was well-tolerated with injection site reactions being the most common AE. Immune response to the vaccine was lower than expected, with 2 current and 2 former smokers developing anti-MUC1 IgG titers ≥2 fold higher at week 12 over baseline (10%). We found high circulating levels of MDSCs in PBMC of both current and former smokers and very low or no serum cytokines. Conclusions: A preventative vaccine trial was feasible in individuals at high risk for lung cancer. However, we discovered a high level of immune suppression, previously documented only in advanced lung cancer. Mitigating the development of lung cancer in heavy smokers through vaccine administration may be limited by related immunosuppression. Citation Format: Olivera J. Finn, Julie Ward, Tami Krpata, Samantha Fatis, John McKolanis, Jia Xue, Pamela Beatty, Camille Jacqueline, Sharon Kaufman, Colleen Akerley, April Felt, Karrie Fursa, Anne Holland, Liz S. Ambulay, Nathan Foster, Ryan McMurray, Carrie Strand, Andres M. Salazar, Lisa Bengtson, Eva Szabo, Paul Limburg, Malgorzata Wojtowicz, David E. Midthun, Arjun Pennathur. A pilot study of a MUC1 vaccine in current and former smokers at high risk for lung cancer. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr PR002.