Effectiveness of vocal fold medialization surgery on the swallowing function of patients with unilateral vocal fold paralysis

Objectives

Vocal fold medialization surgery is generally considered a phonosurgical procedure for improvement of vocal function in patients with glottic insufficiency. However, the literature describing this procedure for the management of dysphagia is limited. This study aims to assess the effects of medialization surgery on swallowing function in patients with unilateral vocal fold paralysis (UVFP).

Methods

We enrolled 32 patients with UVFP undergoing vocal fold medialization surgery (medialization laryngoplasty combined with arytenoid adduction [ML + AA], 12 cases; injection laryngoplasty [IL], 20 cases). We assessed the aerodynamic vocal function including maximum phonation time and mean flow rate to evaluate glottal closure status. The Hyodo score determined by flexible endoscopic evaluation and Functional Oral Intake Scale (FOIS) were evaluated pre- and postoperatively.

Results

Almost 60% of patients with UVFP had dysphagia, and one-third were at high risk for aspiration. Aerodynamic parameters effectively improved after IL and ML + AA. With regard to swallowing, both the FOIS and total Hyodo score were significantly improved postoperatively. We found a particularly significant improvement in pharyngeal clearance. However, patients with high vagal nerve paralysis and postoperative insufficient glottal closure showed poor swallowing benefits after the interventions. In patients with recurrent laryngeal nerve palsy, there were no significant differences in postoperative swallowing function between the ML + AA and IL groups.

Conclusion

Vocal fold medialization surgery was effective in improving swallowing function in most cases with UVFP, except for those with high vagal paralysis and insufficient postoperative glottal closure. Both IL and ML + AA showed an equivalent effect on swallowing improvement.

Level of evidence

3b.

Development of cochlear spiral ligament fibrocytes of the common marmoset, a nonhuman model animal

Spiral ligament fibrocytes generate potassium gradients, which hair cells require to convert mechanical sound waves into electrical palsy. Together with the stria vascularis, they regulate endolymph electrolyte homeostasis. Developing spiral ligament fibrocytes and generating endocochlear potential with an appropriate endolymph ion composition are essential for hearing. Understanding spiral ligament fibrocyte development is useful for studying age-related and genetic hearing loss, as well as for regenerative therapy and cochlear immunology. Despite interspecies differences, most studies of cochlear development have been conducted in rodent models due to the difficulty of using human fetal samples. This study investigated the cochlear development of spiral ligament fibrocytes in a small New World monkey species, the common marmoset (Callithrix jacchus). We examined the developmental expression of specific genes in spiral ligament fibrocytes, including those essential for the generation of endolymphatic potential. Our results showed that this animal model of spiral ligament fibrocyte development is similar to that of humans and is a suitable alternative for the analysis of human cochlear development. The time course established in this study will be useful for studying the primate-specific developmental biology of the inner ear, which may lead to novel treatment strategies for human hearing loss.

Mapping of Notch signaling in the developing organ of Corti in common marmosets

Introduction

The well-regulated development of the sensory epithelium is essential for hearing. This process involves the specification of a pro-sensory epithelium containing common progenitors that differentiate into hair and supporting cells. Notch signaling is one of the most critical pathways during these processes, and its modification is thought to be a feasible approach for treating hearing loss. Despite interspecies differences between rodents and primates or humans, most of our current knowledge regarding cochlear development has been obtained from rodent models.

Methods

We therefore examined and mapped the expression patterns of Notch signal components in the developing cochlea of the common marmoset (Callithrix jacchus), a small monkey species native to the New World, a primate model animal.

Results

In contrast to the preserved expression patterns of the Notch signaling components in the hair cell differentiation between primates and rodents, we unveiled relatively large interspecies differences during the maturation of supporting cells.

Discussion

This improved knowledge of Notch signaling during primate cochlear development will facilitate the development of future regenerative therapies.

Apoptosis of type I spiral ganglion neuron cells in Otof-mutant mice

Otof, which encodes otoferlin, knockout mice are considered model mice for auditory neuropathy spectrum disorder, which is characterized by an absent auditory brainstem response (ABR) despite preserved distortion product otoacoustic emission (DPOAE). Although otoferlin-deficient mice lack neurotransmitter release at the inner hair cell (IHC) synapse, it remains unclear how the Otof mutation affects spiral ganglions. Thus, we used Otof-mutant mice carrying the Otof^{tm1a(KOMP)Wtsi} allele (Otof^tm1a) and analyzed spiral ganglion neurons (SGNs) in Otof^tm1a/tm1a mice by immunolabeling type Ⅰ SGNs (SGN-Ⅰ) and type II SGNs (SGN-II). We also examined apoptotic cells in SGNs. Four-week-old Otof^tm1a/tm1a mice had an absent ABR but normal DPOAEs. The number of SGNs was significantly lower in Otof^tm1a/tm1a mice on postnatal day 7 (P7), P14, and P28 compared with that of wild-type mice. Moreover, significantly more apoptotic SGNs were observed in Otof^tm1a/tm1a mice than in wild-type mice on P7, P14, and P28. SGN-IIs were not significantly reduced in Otof^tm1a/tm1a mice on P7, P14, and P28. No apoptotic SGN-IIs were observed under our experimental conditions. In summary, Otof^tm1a/tm1a mice showed a reduction in SGNs accompanied by apoptosis of SGN-Ⅰs even before the onset of hearing. We speculate that the reduction in SGNs with apoptosis is a secondary defect caused by a lack of otoferlin in IHCs. Appropriate glutamatergic synaptic inputs may be important for the survival of SGNs.

Correlation between genotype and phenotype with special attention to hearing in 14 Japanese cases of NF2-related schwannomatosis

NF2-related schwannomatosis (NF2) is an autosomal dominant genetic disorder caused by variants in the NF2 gene. Approximately 50% of NF2 patients inherit pathogenic variants, and the remainder acquire de novo variants. NF2 is characterized by development of bilateral vestibular schwannomas. The genetic background of Japanese NF2 cases has not been fully investigated, and the present report performed a genetic analysis of 14 Japanese NF2 cases and examined genotype-phenotype correlations. DNA samples collected from peripheral blood were analyzed by next-generation sequencing, multiplex ligation-dependent probe amplification analysis, and in vitro electrophoresis. Ten cases had pathogenic or likely pathogenic variants in the NF2 gene, with seven truncating variants and three non-truncating variants. The age of onset in all seven cases with truncating variants was < 20 years. The age of onset significantly differed among cases with truncating NF2 variants, non-truncating NF2 variants, and no NF2 variants. However, the clinical course of tumor growth and hearing deterioration were not predicted only by germline pathogenic NF2 variants. The rate of truncating variants was higher in the present study than that of previous reports. Genotype-phenotype correlations in the age of onset were present in the analyzed Japanese NF2 cases.

Molecular basis of carotid body tumor and associated clinical features in Japan identified by genomic, immunohistochemical, and clinical analyses

Carotid body tumor (CBT) is classified as a paraganglioma (PGL). Here, we report the genetic background, protein expression pattern, and clinical findings of 30 Japanese CBT cases. Germline pathogenic or likely pathogenic (P/LP) variants of genes encoding succinate dehydrogenase subunits (SDHs) were detected in 15 of 30 cases (50%). The SDHB variants were the most frequently detected, followed by SDHA and SDHD variants. One case with SDHAF2 variant was bilateral CBT, and other two multiple PGL cases were not detected P/LP variants. The three cases with germline variants that could be tested did not have somatic P/LP variants of the same genes. Immunohistochemical analysis showed negative SDHB signals in CBT tissues in five cases with germline P/LP variants of SDHB, SDHD, or SDHA. In addition, SDHB signals in CBT tissues were negative in four of nine cases without germline P/LP variants of SDHs. These findings suggest the involvement of unidentified molecular mechanisms affecting SDHs.

Generation of two induced pluripotent stem cell lines from individuals without auditory disorders

We report the establishment of two human induced pluripotent stem cell (iPSC) lines from individuals without auditory disorders. Extensive audiometry tests were performed to confirm normal hearing. The generated iPSC lines expressed pluripotency genes and showed differentiation capability into the three germ layers. The iPSC lines will be used as controls for pathological analysis and drug screening for ear disorders.

Bilobed Flap for Reconstruction of Skin Defects after Excision of Parotid Carcinoma: A Case Report

OBJECTIVES

Local flaps, pedicled flaps, and free flaps are used to reconstruct medium-sized skin defects after excision of parotid carcinoma. The bilobed flap is a local flap primarily used by plastic surgeons for small defects of nasal skin. We report a case of parotid carcinoma with skin infiltration successfully treated by skin reconstruction with a bilobed flap.

METHODS

An 84-year-old man presented with a parotid mass he had noticed 2 months earlier. Parotid carcinoma with skin infiltration was diagnosed and he underwent radical surgery. The skin defect was round (diameter, 6 cm) and was resected and reconstructed with a bilobed flap designed to be caudal to the defect.

RESULTS

Postoperative facial nerve palsy improved within 6 months. The postoperative course was otherwise uneventful, and the patient was discharged on postoperative day 7. Pathological examination revealed a sarcomatoid salivary duct carcinoma.

CONCLUSIONS

Bilobed flaps are useful for reconstructing skin defects with a diameter of 6 cm or less.

Association between atherosclerosis, hearing recovery, and hearing in the healthy ear in idiopathic sudden sensorineural hearing loss: a retrospective chart analysis

Atherosclerosis is reported to be a risk factor for the severity of idiopathic sudden sensorineural hearing loss (ISSNHL). We evaluated the hypothesis that atherosclerosis affects the hearing thresholds of both the affected and healthy sides of ISSNHL patients. We conducted multivariate analyses on retrospectively collected data of patients with ISSNHL (N = 762) to evaluate the relationship between known factors linked to atherosclerosis and hearing thresholds on affected and healthy sides and whether these factors are prognostic for hearing recovery. Older ages, vertigo or dizziness, diabetes mellitus, and congestive heart failure were significantly related to higher hearing thresholds on the affected side. Older ages, male, and vascular disease were significantly related to higher hearing thresholds on the healthy side. Vertigo or dizziness, severe hearing loss and hearing loss at high frequencies on the affected side, higher hearing thresholds on the healthy side, regular anticoagulant medication, and delayed steroid treatment were significantly related to lack of recovery. Since several atherosclerosis-related factors are associated with higher hearing thresholds on both affected and healthy sides in ISSNHL and higher hearing thresholds on the healthy side predict poorer prognosis, diagnosis, and predicting prognosis of ISSNHL may benefit from rigorous evaluation of patients' cardiovascular comorbidities and hearing levels on both the healthy and affected sides.

Development of the stria vascularis in the common marmoset, a primate model

Stria vascularis is a structure that generates potassium gradients in the cochlea, which is vital for hair cells to convert mechanical sound waves into electrical pulses. The precise development of the stria vascularis and subsequent generation of endocochlear potential are thus essential for hearing. Understanding the development of the stria vascularis is valuable for studying hearing loss caused by aging or genetics and designing regenerative therapy. Although inter-species differences have been reported between rodents and humans, most of our current knowledge regarding cochlear development has been obtained from rodent models because of the difficulty in using human fetal samples in this field of research. Therefore, we investigated the development of the cochlear stria vascularis in the common marmoset (Callithrix jacchus), a small monkey species native to the New World. Our study confirms that stria vascularis development in the common marmoset is similar to that in humans and is suitable for furthering our understanding of human cochlear development. The time course established in this report will aid in studying the primate-specific developmental biology of the inner ear, which could eventually lead to new treatment strategies for hearing loss in humans.

Survival benefit of HER2-targeted or androgen deprivation therapy in salivary duct carcinoma

Background

The efficacy and safety of human epidermal growth factor receptor 2 (HER2)-targeted therapy and androgen deprivation therapy (ADT) for locally advanced or recurrent or metastatic (LA/RM) salivary duct carcinoma (SDC) have been reported in prospective studies. However, the survival benefit of these therapies to conventional therapy remains controversial, and whether HER2-targeted therapy or ADT should be chosen in HER2- and androgen receptor (AR)-positive SDC patients remains unknown.

Methods

Overall, 323 LA/RM SDC patients treated at seven institutions between August 1992 and June 2020 were retrospectively enrolled. The primary aim was to analyze the effect of HER2-targeted therapy and ADT on overall survival from the diagnosis of LA/RM disease to death from any cause (OS1). The secondary indicators included the overall response rate (ORR), clinical benefit rate (CBR), overall survival from therapy initiation for LA/RM disease (OS2), progression-free survival (PFS), time to second progression (PFS2), duration of response (DoR), and duration of clinical benefit (DoCB) of HER2-targeted therapy or ADT as first-line therapy for HER2-positive/AR-positive SDC.

Results

Patients treated with HER2-targeted therapy or ADT had longer OS1 than those treated without these therapies (Median OS1: historical control, 21.6 months; HER2-targeted therapy, 50.6 months; ADT, 32.8 months; HER2-targeted therapy followed by ADT, 42.4 months; and ADT followed by HER2-targeted therapy, 45.2 months, p < 0.001). Among HER2-positive/AR-positive SDC patients, although HER2-targeted therapy had better ORR, CBR, and PFS than those of ADT as first-line therapy, we found no significant differences between HER2-targeted therapy and ADT regarding OS2, PFS2, DoR, and DoCB.

Conclusion

Patients treated with HER2-targeted therapy and ADT showed longer survival in LA/RM SDC. HER2-targeted therapy can be recommended prior to ADT for HER2-positive/AR-positive SDC. It is warranted to establish a biomarker that could predict the efficacy of clinical benefit or better response in ADT.

Early-Phase Adverse Effects and Management of Liposomal Amikacin Inhalation for Refractory Mycobacterium avium Complex Lung Disease in Real-World Settings

Purpose

Amikacin liposome inhalation suspension (ALIS), which efficiently allows amikacin to reach the pulmonary periphery for effect while minimising systemic adverse effects, was recently approved for treating Mycobacterium avium complex (MAC) infections. The international Phase 3 open-label clinical trials showed promising results, contributing to sputum culture conversion, but few studies have examined the efficacy and adverse effects of ALIS using real-world data. We identified the clinical outcome and adverse effects of ALIS in the early phase of treatment, for more effective and safe use in clinical practice.

Patients and Methods

The study population consisted of patients with MAC lung disease (MAC-LD), introduced to ALIS therapy after July 2021 at Keio University Hospital due to poor response to multidrug therapy. The sputum smear/culture results, symptoms, adverse effects, and the serum amikacin concentrations of the early phase of ALIS inhalation therapy were examined.

Results

A total of 11 patients (9 women; median age 64.6 years) were included in this study. The median disease duration of MAC-LD was 13.7 years, and all patients exhibited a positive culture at the beginning of ALIS inhalation. Three of the six patients (50.0%) who were initially sputum-smear-positive were confirmed to have become sputum-smear-negative within one month, including one culture conversion. ALIS inhalation therapy caused some adverse effects in nine patients (81.8%); however, no serious systemic adverse effects were observed. The most common adverse effect was hoarseness (72.7%), which mostly occurred around 1 week after initiation. The medians of peak serum amikacin concentrations were 1.4 and 2.3 μg/mL for the first and third inhalations, respectively. Trough serum concentrations just before the third inhalation were <1.2 μg/mL in all patients.

Conclusion

ALIS therapy might be a treatment option for patients with refractory MAC infection with long disease duration and a poor response to guideline-based therapy.

Effects of hearing aids in patients with unilateral tinnitus with acquired ipsilateral sensorineural hearing loss

OBJECTIVES

To evaluate the effectiveness of sound therapy using hearing aids in patients experiencing tinnitus with acquired unilateral sensorineural hearing loss.

METHODS

A total of 97 patients with unilateral tinnitus with acquired ipsilateral sensorineural hearing loss were included. Evaluation involved self-report questionnaires administered at entry, 3 months after treatment, and 1 year after treatment.

RESULTS

The mean Tinnitus Handicap Inventory score before treatment decreased significantly (p < 0.01) at 3 months (50.0 ± 24.5-12.7 ± 16.2), and 1 year (53.3 ± 25.5-8.79 ± 13.9), after treatment. Moreover, the visual analog scale score decreased significantly at 3 months (loudness, 69.6 ± 21.9-29.1 ± 27.2; annoyance, 71.1 ± 24.7-22.7 ± 25.5) and 1 year (loudness, 69.8 ± 22.0-21.1 ± 26.1; annoyance, 72.7 ± 25.6-19.4 ± 27.6). Approximately 80-90% of patients noticed improvements in tinnitus annoyance and loudness, as determined by their responses to the questionnaires of subjective symptom improvement.

CONCLUSIONS

Hearing aids are remarkably effective for patients with unilateral tinnitus with acquired ipsilateral sensorineural hearing loss.

Abstract 5210: Tumor immune characterization identifies age-stratified biomarkers for nivolumab in patients with head and neck squamous cell carcinoma: A nationwide collaborative study in Japan

Background: Biomarkers predicting therapeutic response to immunotherapy have been widely explored via monitoring the liquid and tissue-derived components. Increasing treatment options for recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) mandates prediction of the therapeutic response of anti-PD-1 antibody alone as well as optimization of the treatment sequence. In view of improving biomarkers predicting the efficacy of immunotherapy for R/M HNSCC, we hypothesized that biomarkers can be personalized depending on clinicopathological backgrounds and treatment sequence.

Methods: In this study, we retrospectively included formalin-fixed paraffin-embedded (FFPE) samples, peripheral blood cell counts at treatment, clinicopathological information, and outcome data for patients with R/M HNSCC receiving nivolumab across 22 institutions in Japan (N = 100). FFPE samples were subjected to 14-marker multiplex immunohistochemistry (IHC) and image cytometry analysis (Tsujikawa T et al. Cell Reports, 2017) to quantitatively evaluate CD8+ T cells, helper T cells, regulatory T cells, B cells, natural killer (NK) cells, macrophages, dendritic cells, CD66b+ granulocytes, mast cells, programmed death ligand 1 (PD-L1) and PD-1 expression in a single slide. Intratumoral and circulating immune cell frequencies were comparatively analyzed between responders (CR, n = 14; PR, n = 39) and non-responders (SD, n = 2; PD, n = 45).

Results: Of 100 patients included, responders had significantly lower smoking and alcohol index, higher incidence of immune related adverse events, and higher PD-L1 expression in immune cells as well as PD-L1 combined positive score (CPS) than non-responders. Next, focusing on the history of prior therapy, stratified analysis revealed that the frequency of NK cells was associated with nivolumab response in patients with prior cetuximab use, but not in cetuximab-naïve status. Furthermore, stratified analysis by patient age revealed that nivolumab response was significantly associated with high CPS and lymphoid-inflamed profiles based on cell densities of nine immune cell lineages in the group aged 65 years or older, but not in the group under 65 years of age. On the contrary, the neutrophil/lymphocyte ratios (NLR) in peripheral blood counts at nivolumab treatment were significantly lower in responders (mean 4.96) than those in non-responders (mean 10.46) in the group under 65 years of age, but not in those over 65 years of age (7.41 versus 8.47).

Conclusions: Using peripheral blood data and tumor tissue profiling stratified by patient age and prior treatment might provide better predictive biomarkers in nivolumab response to HNSCC. Further preclinical and clinical studies elucidating immune mechanisms in different patient backgrounds will be warranted.

Citation Format: Takahiro Tsujikawa, Kazuchika Ohno, Sumiyo Saburi, Junichi Mitsuda, Kanako Yoshimura, Alisa Kimura, Hiroki Morimoto, Gaku Ohmura, Akihito Arai, Hiroshi Ogi, Saya Shibata, Yosuke Ariizumi, Akihisa Tasaki, Ryosuke Takahashi, Yumiko Tateishi, Hiroaki Kawabe, Sadakatsu Ikeda, Kei-ichi Morita, Tatsuhiko Tsunoda, Takumi Akashi, Morito Kurata, Issei Imoto, Yasushi Shimizu, Akihito Watanabe, Yukinori Asada, Ryuichi Hayashi, Yuki Saito, Hiroyuki Ozawa, Kiyoaki Tsukahara, Nobuhiko Oridate, Arata Horii, Takashi Maruo, Nobuhiro Hanai, Hidenori Inohara, Hiroshi Iwai, Takashi Fujii, Ken-ichi Nibu, Shigemichi Iwae, Tsutomu Ueda, Ryuji Yasumatsu, Hirohito Umeno, Muneyuki Masuda, Kyoko Itoh, Shigeru Hirano, Takahiro Asakage. Tumor immune characterization identifies age-stratified biomarkers for nivolumab in patients with head and neck squamous cell carcinoma: A nationwide collaborative study in Japan [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5210.

Early development of the cochlea of the common marmoset, a non-human primate model

Background

Fine-tuned cochlear development is essential for hearing. Owing to the difficulty in using early human fetal samples, most of our knowledge regarding cochlear development has been obtained from rodents. However, several inter-species differences in cochlear development between rodents and humans have been reported. To bridge these differences, we investigated early otic development of a non-human primate model animal, the common marmoset (Callithrix jacchus).

Methods

We examined 20 genes involved in early cochlear development and described the critical developmental steps for morphogenesis, which have been reported to vary between rodents and marmosets.

Results

The results revealed that several critical genes involved in prosensory epithelium specifications showed higher inter-species differences, suggesting that the molecular process for hair cell lineage acquisition in primates differs considerably from that of rodents. We also observed that the tempo of cochlear development was three times slower in the primate than in rodents.

Conclusions

Our data provide new insights into early cochlear development in primates and humans and imply that the procedures used for manipulating rodent cochlear sensory cells cannot be directly used for the research of primate cells due to the intrinsic inter-species differences in the cell fate determination program.

Utility of computed tomography findings as a predictor of carotid artery invasion by metastatic lymph nodes in head and neck squamous cell carcinoma

PURPOSE

Carotid artery invasion by metastatic lymph nodes in head and neck squamous cell carcinoma (HNSCC) is one of the diagnostic criteria for unresectable tumors. However, to date, the diagnostic criteria for carotid artery invasion have not been well documented. This study investigated the utility of computed tomography (CT) findings as a predictor of carotid artery invasion by metastatic lymph nodes in HNSCC.

METHODS

Twenty-eight patients who had metastatic lymph nodes of HNSCC attached to the carotid artery as seen on CT images before neck dissection from January 2011 to November 2017 were included. Five imaging parameters (angle of contact [AC], length of contact [LC], haziness of the carotid artery wall [HW], size of the lymph node, and involvement of the bifurcation of the carotid artery [IB]) were assessed using CT to predict carotid artery invasion. Furthermore, the utility of the combination of these five parameters was evaluated.

RESULTS

There were significant differences in AC, LC, and IB between patients with and without carotid artery invasion. There were significant differences in all combinations of the two image findings between patients with and without carotid artery invasion. In particular, the combinations of LC and HW, and LC and IB could clearly predict carotid artery invasion.

CONCLUSION

AC, LC, and IB were useful predictors of carotid artery invasion of metastatic lymph nodes in HNSCC. This study is the first to report that IB is a useful predictor of carotid artery invasion in HNSCC.

Cricotracheostomy in a patient with severe kyphosis: A case report

Cricotracheostomy is a useful surgical procedure for opening the airway in cases where conventional tracheotomy is difficult. This is a safe and easy technique involving removal of the anterior portion of the cricoid cartilage. Herein, we report the case of a patient with difficulty in neck extension due to severe kyphosis, who underwent cricotracheostomy. A 65-year-old woman developed dyspnea and was transported to our hospital. SpO2 was 60% (room air) and endotracheal intubation was performed. She was managed on ventilator. However, weaning off the ventilator was difficult, and endotracheal intubation was prolonged. Subsequently, the patient was referred to us for a tracheostomy. The patient was unable to maintain the supine position due to severe kyphosis, and computed tomography revealed that the brachiocephalic artery was running just below the thyroid gland. Therefore, conventional tracheostomy was difficult to perform, and we performed cricotracheostomy instead. After the cricotracheostomy, there were no tracheal problems, such as tracheal stenosis and stomal hemorrhage. Cricotracheostomy can be performed in cases where multiple anatomical difficulties may be faced in the tracheostomy site, as in this case. Furthermore, cricotracheostomy is beneficial for long-term airway management because it causes fewer complications compared to conventional tracheotomy.

Long-Term Outcomes of Endoscopic Cyst Fenestration for Rathke Cleft Cyst

OBJECTIVE

We sought to elucidate the long-term surgical outcomes and incidence of recurrence and reoperation of endoscopic endonasal cyst fenestration for Rathke cleft cyst (RCC).

METHODS

A retrospective review of the chart and operation record of RCC surgical cases between January 2008 and August 2021 at our institution was conducted. Patient characteristics, intraoperative findings, and postoperative follow-up outcomes were evaluated.

RESULTS

A total of 27 patients were analyzed, with a median postoperative follow-up period of 52 months (range, 1-150 months). Preoperative symptoms were visual dysfunction (59%), headache (41%), and pituitary dysfunction (22%). Endoscopic cyst fenestration was performed in all patients. Ten (37%) patients had intraoperative cerebrospinal fluid leakage. Among them, the only patient in whom sellar floor reconstruction was not performed experienced a repair operation due to postoperative cerebrospinal fluid leakage. No patients experienced postoperative hypopituitarism. Preoperative headache, visual dysfunction, and pituitary hormone disorder improved in 73%, 75%, and 67% of patients, respectively. Although postoperative cyst regrowth was observed in 8 patients (30%), no patient experienced worsening or novel symptoms and none required reoperation.

CONCLUSIONS

Patients with a symptomatic RCC can be effectively treated with endoscopic endonasal cyst fenestration. Reversal of the presenting symptoms resulted, including headache, visual dysfunction, and pituitary hormone dysfunction, in the majority of patients. In our series, appropriate reconstruction of the sellar floor reduced the risk of postoperative cerebrospinal fluid leakage without impacting cyst regrowth. This simple technique appears to effectively disrupt cyst progression in most cases, even after a relatively long-term follow-up period.

The Role of the EZH2 and H3K27me3 Expression as a Predictor of Clinical Outcomes in Salivary Duct Carcinoma Patients: A Large-Series Study With Emphasis on the Relevance to the Combined Androgen Blockade and HER2-Targeted Therapy

Objective

Salivary duct carcinoma (SDC) is a highly aggressive and uncommon tumor arising not only de novo but also in pleomorphic adenoma. Androgen receptor (AR)- and HER2-targeted therapy have recently been introduced for SDC as promising treatment options; however, no predictive biomarkers have yet been established. EZH2 and H3K27me3 are closely linked to the development and progression of various cancers, and EZH2 is also expected to be a desirable therapeutic target. We therefore explored the clinicopathological and prognostic implications of EZH2 and H3K27me3 in a large cohort of SDC patients, focusing on their impact on the therapeutic efficacy of AR- or HER2-targeted therapy.

Materials and Methods

The EZH2 and H3K27me3 immunohistochemical expression and EZH2 Y646 gain-of-function mutation status were examined in 226 SDCs, and the relationship with the clinicopathological factors as well as clinical outcomes were evaluated within the three groups depending on the treatment: AR-targeted (combined androgen blockade with leuprorelin acetate and bicalutamide; 89 cases), HER2-targeted (trastuzumab and docetaxel; 42 cases), and conventional therapy (112 cases).

Results

EZH2 and H3K27me3 were variably immunoreactive in most SDCs. A positive correlation was found between the expression of EZH2 and H3K27me3. The EZH2 expression in the SDC component was significantly higher than that in the pre-existing pleomorphic adenoma component. EZH2 Y646 was not identified in any cases. EZH2-high cases more frequently had an advanced clinical stage and aggressive histological features than EZH2-low cases. An EZH2-high status in patients treated with AR-targeted therapy was associated with a significantly shorter progression-free and overall survival as well as a lower objective response rate and clinical benefit rate. In addition, a H3K27me3-high status in patients treated with AR-targeted therapy was related to a shorter overall survival. Conversely, there was no association between the EZH2 and H3K27me3 expression and the clinical outcomes in the conventional or HER2-targeted therapy groups.

Conclusions

A high expression of EZH2 and H3K27me3 in SDC might be a predictor of a poor efficacy of AR-targeted therapy. Our data provide new insights into the role of EZH2 and H3K27me3 in therapeutic strategies for SDC.

Transcanal endoscopic ear surgery for management of ossicular malformation: clinical outcomes of 17 cases

BACKGROUND

In recent years, transcanal endoscopic ear surgery (TEES) is known as an innovative and minimally invasive surgery.

AIMS

To clarify the usefulness of TEES for the ossicular malformation, we performed a retrospective study.

MATERIAL AND METHODS

We examined cases of ossicular malformation performed using TEES at our hospital between April 2015 and April 2020.

RESULTS

The hearing level results were countable for 16 cases. Post-operative hearing levels were significantly improved. Transient nausea, tongue paralysis, and taste disorders were observed; however, no other complications were observed. In 2015-2018, some of the cases required the assistance of a surgical microscope. In contrast, all the cases were performed by TEES after 2019 using a powered device to curve the canal.

CONCLUSIONS AND SIGNIFICANCE

TEES requires considerable training, and the sensation of depth is difficult to acquire. However, this less invasive method is also helpful for ossicular malformation cases.

Analysis of conductive olfactory dysfunction using computational fluid dynamics

Conductive olfactory dysfunction (COD) is caused by an obstruction in the nasal cavity and is characterized by changeable olfaction. COD can occur even when the olfactory cleft is anatomically normal, and therefore, the cause in these cases remains unclear. Herein, we used computational fluid dynamics to examine olfactory cleft airflow with a retrospective cohort study utilizing the cone beam computed tomography scan data of COD patients. By measuring nasal–nasopharynx pressure at maximum flow, we established a cut-off value at which nasal breathing can be differentiated from combined mouth breathing in COD patients. We found that increased nasal resistance led to mouth breathing and that the velocity and flow rate in the olfactory cleft at maximum flow were significantly reduced in COD patients with nasal breathing only compared to healthy olfactory subjects. In addition, we performed a detailed analysis of common morphological abnormalities associated with concha bullosa. Our study provides novel insights into the causes of COD, and therefore, it has important implications for surgical planning of COD, sleep apnea research, assessment of adenoid hyperplasia in children, and sports respiratory physiology.

Neuronal development in the cochlea of a nonhuman primate model, the common marmoset

Precise cochlear neuronal development is vital to hearing ability. Understanding the developmental process of the spiral ganglion is useful for studying hearing loss aimed at aging or regenerative therapy. Although interspecies differences have been reported between rodents and humans, to date, most of our knowledge about the development of cochlear neuronal development has been obtained from rodent models because of the difficulty in using human fetal samples in this field. In this study, we investigated cochlear neuronal development in a small New World monkey species, the common marmoset (Callithrix jacchus). We examined more than 25 genes involved in the neuronal development of the cochlea and described the critical developmental steps of these neurons. We also revealed similarities and differences between previously reported rodent models and this primate animal model. Our results clarified that this animal model of cochlear neuronal development is more similar to humans than rodents and is suitable as an alternative for the analysis of human cochlear development. The time course established in this report will be a useful tool for studying primate‐specific neuronal biology of the inner ear, which could eventually lead to new treatment strategies for human hearing loss.

Trapezius muscle branch of the spinal accessory nerve without penetrating the sternocleidomastoid muscle as a pitfall in neck dissection: prevalence in a Japanese institution and a protocol for the prevention of iatrogenic injury

BACKGROUND

The spinal accessory nerve (SAN) has several anatomical variations, which may be a pitfall in neck dissection (ND). These include the trapezius muscle branch (TB), which stems from the common trunk before entering the sternocleidomastoid muscle (SCM).

AIMS/OBJECTIVES

To investigate the prevalence of this variation and suggest a protocol for preventing unexpected injury of the TB in ND.

MATERIALS AND METHODS

We conducted a retrospective cohort study for 93 patients who had undergone neck dissection (117 sides) without resection of the SCM nor SAN. We recorded the division of the TB after and before penetration of the SCM by the common trunk (penetrating type TB [PTB]) and non-penetrating type TB [NPTB], respectively).

RESULTS

Among NDs, PTB and NPTB were observed in 61 (52%) and 56 (48%) sides, respectively. In the subgroup of 24 cases with bilateral ND, PTB/PTB, NPTB/NPTB, and NPTB/PTB were observed in eight (33%), nine (38%), and seven (29%) cases, respectively. The prevalence of PTB/NPTB did not differ according to age, sex, or laterality.

CONCLUSIONS AND SIGNIFICANCE

NPTB is a common anatomical variation. The presence or absence of a branch from the common trunk must be initially checked to avoid unexpected damage to the TB.

Effectiveness of hearing aids in treating patients with chronic tinnitus with average hearing levels of <30 dBHL and no inconvenience due to hearing loss

BACKGROUND

The effectiveness of hearing aids for tinnitus patients without hearing loss in conversation-comprehension range and inconvenience in daily communication is unknown.

OBJECTIVE

We aimed to evaluate their therapeutic effect.

MATERIALS AND METHODS

We included 91 patients with average hearing levels <30 dBHL. To determine the effects, self-reported questionnaires were used. Data were collected at the entry and 3 months (n = 91) and 1 year (n = 70) after treatment initiation.

RESULTS

All scores (mean ± standard deviation) decreased significantly (p < 0.0001) from before treatment to 3 months and 1 year after treatment: tinnitus handicap inventory score: from 56 ± 21 to 17 ± 17 and 13 ± 15; visual analogue scale (VAS) score for tinnitus loudness: from 71 ± 20 to 31 ± 26 and 28 ± 29; VAS score for tinnitus annoyance: 79 ± 20 to 27 ± 25 and 26 ± 30, respectively. Approximately 90% of patients noticed improvements in tinnitus annoyance and loudness, as determined by the questionnaires regarding subjective symptom improvement.

CONCLUSIONS

Hearing aids may be useful for tinnitus patients without hearing loss and inconvenience in daily communication.

SIGNIFICANCE

Our findings provide a treatment option for tinnitus patients with an average hearing level of <30 dBHL.

Dynamic Spatiotemporal Expression Changes in Connexins of the Developing Primate's Cochlea

Connexins are gap junction components that are essential for acquiring normal hearing ability. Up to 50% of congenital, autosomal-recessive, non-syndromic deafness can be attributed to variants in GJB2, the gene that encodes connexin 26. Gene therapies modifying the expression of connexins are a feasible treatment option for some patients with genetic hearing losses. However, the expression patterns of these proteins in the human fetus are not fully understood due to ethical concerns. Recently, the common marmoset was used as a primate animal model for the human fetus. In this study, we examined the expression patterns of connexin 26 and connexin 30 in the developing cochlea of this primate. Primate-specific spatiotemporal expression changes were revealed, which suggest the existence of primate-specific control of connexin expression patterns and specific functions of these gap junction proteins. Moreover, our results indicate that treatments for connexin-related hearing loss established in rodent models may not be appropriate for human patients, underscoring the importance of testing these treatments in primate models before applying them in human clinical trials.