Transoral robotic surgery (TORS) in Japan: procedures, advantages and current status

Transoral robotic surgery (TORS), introduced by Weinstein et al. in 2005, has been widely adopted as a minimally invasive procedure, particularly for the treatment of patients with early stage oropharyngeal cancer. TORS is typically performed using the da Vinci Surgical System, similar to robot-assisted surgeries for other malignancies. The main difference between TORS and these other robot-assisted surgeries is that it is performed through the natural orifice of the mouth, which limits the surgical working space, and that it progresses from the lumen of the pharynx to the deeper tissues. The advantages of TORS are mainly due to the benefits of using the da Vinci Surgical System, such as three-dimensional high-definition images, magnification, multiple forceps articulation, tremor-stabilization function and motion scale function. To date, many big data and meta-analyses have shown that TORS is superior to conventional surgeries, such as open surgery, in terms of oncological outcomes, post-operative functionality and quality of life. In Japan, TORS is expected to spread across the country, as it has been covered by health insurance since April 2022. This review highlights the procedures of TORS, its unique aspects, its unparalleled advantages as a minimally invasive surgery for treating laryngeal and pharyngeal cancers, and its current status in Japan.

A Combined Exoscopic and Endoscopic Approach for Radical Temporal Bone Resection and Usefulness of the Endoscopic Approach to the Medial Aspect of the Temporal Bone

Radical temporal bone resection (TBR) for lateral skull base malignancies is technically challenging because of the vital anatomical structures located at the medial part of the temporal bone and their limited exposure. A possible solution is to adopt an additional endoscopic approach for medial osteotomy to reduce blind spots. The authors aimed to describe a combined exoscopic and endoscopic approach (CEEA) for cranial dissection in radical TBR and to determine the usefulness of the endoscopic approach to the medial aspect of the temporal bone. Having utilized the CEEA in for cranial dissection in radical TBR since 2021, the authors included 5 consecutive patients who underwent the procedure between 2021 and 2022. All surgeries were successful and resulted in no significant complications. The additional use of an endoscope improved visualization of the middle ear in 4 patients and that of the inner ear and carotid canal in 1 patient, enabling precise and safe cranial dissection. Furthermore, surgeons experienced reduced intraoperative postural stress with CEEA than with a microscopic approach. The main advantage of CEEA in radical TBR was the extension of the viewing angles of the endoscope, which allowed observation of the medial aspect of the temporal bone and limited tumor exposure and injury to vital structures. Given the other benefits of exoscopes and endoscopes, including compact size, ergonomics, and surgical field accessibility, CEEA proved to be an efficient treatment option for cranial dissection in radical TBR.

Efficacy of endoscopic cricopharyngeal myotomy using a curved rigid laryngoscope in patients with sporadic inclusion body myositis: four retrospective case reviews

Sporadic inclusion body myositis (s-IBM) is an acquired degenerative inflammatory myopathy that leads to slowly progressive muscle weakness and atrophy of the limbs, face, and pharynx. Owing to the slow progression of the disease, the indications for surgical intervention remain unclear. Herein, we retrospectively reviewed the records of four patients with s-IBM who had undergone cricopharyngeal myotomy for severe dysphagia at our institution between 2016 and 2021. Among these, one patient underwent transcervical cricopharyngeal myotomy and laryngeal suspension, as videofluoroscopic examination of swallowing revealed poor laryngeal elevation. The remaining three patients underwent endoscopic cricopharyngeal myotomy using a curved rigid laryngoscope. Preoperatively, the mean Hyodo score was 8 points (range: 6-10) using a flexible endoscope. The mean surgical duration was 104 min, and no severe complications were observed. Postoperatively, all patients achieved improvement in swallowing function and food intake. Moreover, swallowing function was maintained in all four patients even 6-12 months postoperatively. Cricopharyngeal myotomy may be a safe surgical procedure with the potential to improve swallowing function, and a Hyodo score of 6 may be considered a surgical indication for cricopharyngeal myotomy in patients with s-IBM.

Dynamic Analysis Of Male "Extra-high Voice" Using Multi-row Detector Computed Tomography

OBJECTIVES/HYPOTHESIS

Some people who practice singing on a daily basis may be able to produce a voice higher than the upper limit of the normal range (extra high voice), but there is much regarding the movement of the larynx that remains unknown. We have been conducting dynamic analysis of the larynx using multi-row detection computed tomography (MD-CT) at our university and report herein an analysis of the extra high voice.

STUDY DESIGN

Observational.

METHODS

Images of a normal male participant capable of extremely high-frequency speech (the highest speech range is C7 [2093 Hz] and the singing application range is up to B5 [988 Hz]) during speech were captured by MD-CT. The acquisition time was 2 seconds, and the rise of the voice from low to high and then to very high tones was recorded. Ten frames per second were analyzed as three-dimensional images.

RESULTS

In the fundamental frequency range from A3 to D5 (220-587 Hz), laryngeal elevation movements were observed as the voice rose in pitch. However, posterior upward displacement of the laryngeal cartilage was observed as the frequency range increased from E5 to B5 (659-988 Hz).

CONCLUSIONS

In the E5-B5 range, laryngeal movements were different from those observed in the previous range. MD-CT analysis is useful in the study of this range because it allows visualization of laryngeal movements that are unclear using endoscopy or external examination.

Immune Status of Cervical Lymph Nodes in Head and Neck Cancer-A Surgical Oncology Perspective

Neck dissection for cervical lymph node metastasis is an established procedure for head and neck cancer (HNC). However, with the advent of immunotherapy, head and neck surgical oncologists need to rethink removing all lymph nodes, including those with immune function. We investigated the anti-cancer immune response of the cervical lymph nodes in four patients with human papillomavirus type 16 (HPV16)-positive head and neck squamous cell carcinoma. Using lymphocytes extracted from local, metastatic, and non-metastatic lymph nodes and peripheral blood from these patients, we performed an intracellular flow cytometric cytokine assay using anti-IFNγ and anti-TNF-α monoclonal antibodies to detect HPV16 E6- and E7-specific T cells. HPV status and p16 immunostaining were determined by in situ detection using the HPV RNAscope method and immunohistochemistry. In one case, E6-specific and E7-specific CD8+ T cells were detected in proximal metastatic nodes and distal non-metastatic nodes. This finding suggests that non-metastatic nodes should be preserved for their immune function during neck dissection and that the immune function of non-metastatic lymph nodes is important when administering immunotherapy. In this context, head and neck surgical oncologists treating HNC should consider the place of immunotherapy and neck dissection in the treatment of HNC.

＜Editors' Choice＞ Long-term outcomes of lateral skull base reconstruction with a free omental flap and facial nerve reconstruction

In lateral skull base reconstruction, it is necessary to seal the defect in the lateral skull base, fill the dead space, and, sometimes, reconstruct the facial nerve. However, this procedure is difficult to perform with a standard musculocutaneous flap. Therefore, for such cases, an omental flap is used in our hospital because of its flexibility. In this study, we report our experience with the procedure (lateral skull base reconstruction with a free omental flap) and its long-term outcome and facial nerve reconstruction, with special focus on facial nerve recovery. This study is a technical note and a retrospective review. It was conducted in Nagoya University Hospital. Overall, 16 patients (12 women and 4 men; mean age: 55.1 years) underwent lateral skull base reconstruction with a free omental flap after subtotal temporal bone resection or lateral temporal bone resection during 2005-2017. The main outcome measures were postoperative complications and facial nerve recovery: Yanagihara score and House-Brackmann grading system. Complications included partial necrosis and minor cerebrospinal fluid leakage in 2 patients. Facial nerve recovery could be observed more than 12 months after surgery, with a mean Yanagihara score of 19.6 and House-Brackmann grade of 3.60. The free omental flap is a reliable method for lateral skull base reconstruction, especially in cases where facial nerve reconstruction is needed. To the best of our knowledge, this is the first report on facial nerve recovery after lateral skull base reconstruction.

Safety and Clinical Benefits of Laryngeal Closure in Patients with Amyotrophic Lateral Sclerosis

This study evaluated the safety of laryngeal closure and post-surgical changes in swallowing function of patients with amyotrophic lateral sclerosis (ALS) and proposed an appropriate surgical strategy for patients with ALS. Clinical and surgical data of 26 consecutive patients with ALS who underwent laryngeal closure at Nagoya University Hospital in Japan between 2003 and 2020 were retrospectively analyzed. Changes in swallowing functions were evaluated before and approximately 1 month post-surgery using Neuromuscular Disease Swallowing Status Scale (NdSSS), and Functional Oral Intake Scale (FOIS). The median operation time was 126 min (range, 51-163 min), and the median intraoperative blood loss was 20 mL (range, 0-88 mL). Among the 26 ALS patients who underwent laryngeal closure, grade 1 (mild) complications occurred in three patients (12%); however, no severe complications were observed. After surgery, 25 patients (96%) maintained the swallowing function and only one patient (4%) had deteriorating NdSSS and FOIS scores. No patients were referred to our hospital due to severe aspiration pneumonia after the surgery. Two patients did not require a feeding tube after the surgery and returned to oral intake. Laryngeal closure may be a safe surgical procedure for preventing chronic aspiration and may also maintain swallowing function of patients with ALS. Further multicenter prospective studies using the gold standard videofluoroscopic swallowing examination are required to support our findings.

New, safe and simple endoscopic cricopharyngeal myotomy with a curved rigid laryngoscope: A case report

Endoscopic cricopharyngeal myotomy (ECPM) is a safe and minimally invasive technique that is used to treat patients whose esophageal inlet fails to open because of specific diseases, such as Wallenberg's syndrome and neuromuscular diseases. The present study described the performance of a new, safe and simple ECPM using a curved rigid laryngoscope, which is used for endoscopic laryngopharyngeal surgery for patients with dysphagia due to pharyngeal residue after swallowing. The patient was an 80-year-old woman with laryngeal palsy caused by lower cranial nerve palsy after cranial base schwannoma surgery. ECPM was performed with a curved rigid laryngoscope. The postoperative course was good; postoperative rehabilitation eliminated the residue after swallowing a thickened solution and mealtimes were shorter than before surgery. This procedure allows the hypopharynx to be widely expanded and it is possible to develop a wider surgical field than when using a direct laryngoscope. In addition, this procedure appears to be relatively easy to perform if the surgeon is familiar with the curved rigid laryngoscope technique.

Real-world treatment patterns and outcomes in Japanese patients with cervical esophageal cancer

BACKGROUND

Cervical esophageal cancer (CEC) carries a poor prognosis; however, due to its low incidence, optimal treatment for CEC remains to be established. The purpose of this study was to clarify the current status of treatment of CEC in Japan and obtain evidence for establishing the appropriate treatment method.

PATIENTS AND METHODS

We asked specialist training facilities accredited by the Japanese Broncho-Esophageal Society to register data on CEC cases that received curative treatment from January 2009 to December 2014, and conducted a retrospective review of the clinical data of 302 cases registered from 27 facilities.

RESULTS

In regard to the initial therapy, of the 302 patients, 33 had undergone endoscopic resection, 41 had undergone surgery, 67 had received induction chemotherapy (IC), and 143 had received chemoradiotherapy (CRT). There were no significant differences in the 5-year overall survival rates among the patient groups that had received surgery, IC or CRT as the initial treatment; advanced stage and recurrent nerve invasion were identified as independent poor prognostic factors. Among the patients who had received IC or CRT as laryngeal-preserving surgery was not indicated at the time of the initial diagnosis, the functional laryngeal preservation rate at the end of the observation period was 34.8%.

CONCLUSION

Even in patients with advanced CEC, there is the possibility of preserving the larynx by adopting IC or CRT. However, if the laryngeal function cannot be preserved, there is a risk of complications from aspiration pneumonia, so that the choice of treatment should be made carefully.

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.

Predictive factors for false negatives following sentinel lymph node biopsy in early oral cavity cancer

Prophylactic elective neck dissection (ND) with navigation surgery using radioisotope-based sentinel lymph node biopsy (SLNB) is non-inferior to elective ND in terms of survival but has an advantage in postoperative functional disability. We conducted a subgroup analysis to identify predictive factors for false-negative (FN)-SLNB in patients with early oral cavity cancer. This study is a supplementary analysis using the dataset of a previously reported randomized clinical trial on SLN navigation surgery for oral cancers. This study investigated the association of clinical and SLN-related factors with false-negative cases in the SLNB group. From 2011 to 2016, 275 patients were enrolled and randomly assigned to the ND and SLNB study groups, with 134 patients assigned to the SLNB group. In the SLNB group, seven cases with negative SLNs and neck recurrences were judged as FN-SLNBs according to the general definition. The number of detected SLNs with and without adjusting for the propensity score was significantly associated with FNs in the logistic analysis. FN-SLNB was associated with the number of identified SLNs, suggesting the need for careful postoperative monitoring for neck recurrence in patients with one or two identified SLNs after acquiring sufficient experience in the identification technique.

Surgical Strategy for Squamous Cell Carcinoma of the External Auditory Canal: Management of Locally Advanced Cases with Skull Base Involvement

Objective  Surgical indications for advanced-stage squamous cell carcinoma (SCC) of the external auditory canal (EAC) are highly dependent on the skull base surgery team. The aim of this study was to evaluate the surgical outcomes in patients with SCC of the EAC and to clarify the surgical indication of far advanced cases using the T4 subclassification. Methods  Patients with SCC of the EAC who underwent curative treatment from 2002 to 2021 at our hospital were retrospectively reviewed. Clinical and surgical results, including operative data, overall survival (OS), and disease-specific survival (DSS), were analyzed. To clarify the surgical indication for advanced-stage tumors, we proposed the T4 subclassification. Results  In the 46 patients included in the study, 8 patients had T1 tumors, 10 had T2 tumor, 5 had T3 tumors, and 23 had T4 tumors. The 5-year DSS with T1, T2, T3, and T4 tumors were 100, 85.7, 100, and 61.7%, respectively. No prognostic impacts for margin status were found between the 5-year OS and DSS ( p  = 0.23 and 0.13, respectively). Patients with far-advanced-stage (T4b) tumors were significantly associated with shorter DSS than those with early-stage (T1/T2) and advanced-stage (T3/T4a) tumors ( p  = 0.007 and 0.03, respectively). Conclusion  The present study focused on patients with SCC of the EAC at a university hospital over a period of 20 years, especially with skull base involvement, and a T4 subclassification was proposed. Complete tumor resection in an en bloc fashion could help achieve a good survival rate even in patients with locally advanced tumors.

Current Status of Transoral Surgery for Patients With Early-Stage Pharyngeal and Laryngeal Cancers in Japan

As the laryngopharynx is closely related to swallowing, speech, and phonation, it is necessary to consider not only disease control but also a minimally invasive approach for the treatment of laryngopharyngeal cancer. Transoral surgery has been reported to be a minimally invasive method for treating these diseases. Transoral videolaryngoscopic surgery (TOVS) and endoscopic laryngo-pharyngeal surgery (ELPS) have been developed in Japan and recently emerged as treatments for patients with early stage pharyngeal and laryngeal cancers. However, securing an appropriate field of view and a narrow operating space during TOVS or ELPS are critical issues to be resolved for these surgeries. The clinical significance and safety of transoral robotic surgery (TORS) using the da Vinci Surgical System have been widely reported to provide surgeons with increased visualization and magnification, resulting in precise surgical margins and rapid functional recovery. In this context, a multi-institutional clinical study was conducted to evaluate the treatment outcomes of TORS for the treatment of laryngopharyngeal cancer in Japan, and the da Vinci Surgical System for oral robot-assisted surgery for these diseases was approved by the Pharmaceutical Affairs Agency in August 2018. This review provides an overview of the therapeutic effects of TOVS, ELPS, and TORS, with a particular focus on these therapeutic results in Japan.

Motor Functional Characteristics in Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorders: A Systematic Review

BACKGROUND

The development of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASDs) has various influences on physical abilities. Identification of specific physical abilities of people with ADHD/ASDs as biomarkers for diagnosing these conditions is necessary. Therefore, in the present review, we aimed firstly to extract the difference in physical abilities of people with ADHD or ASDs compared to those of normal individuals. Secondly, we aimed to extract the specific physical ability characteristics for identifying potential diagnostic biomarkers in people with ADHD/ASDs.

METHODS

A systematic literature review was performed. The databases were searched for relevant articles on motor function deficits and characteristics of ADHD or ASD.

RESULTS

Forty-one cross-sectional studies and three randomized controlled trials were identified, comprising 33 studies of ADHD, 10 studies of ASDs, and 1 study of both ADHD and ASDs. The quality of studies varied. Three types of physical activities/exercises were identified, including coordinated movement, resistance-type sports, and aerobic-type sports. People with ADHD/ASDs generally exhibited poorer physical abilities for all types of activities, possibly because of low levels of physical activity. Specifically, we found temporal discoordination of movement in ADHD and integration or synchronization of separate movements in ASDs.

CONCLUSION

Specific deficits in physical ability may be attributed to ADHD/ASDs. However, there is not enough research on the physical abilities of people with ADHD and ASDs to clarify the specific deficits. Investigation of specific motor functions that characterize ADHD/ASDs should be facilitated.

Factors affecting mental illness and social stress in hospital workers treating COVID-19: Paradoxical distress during pandemic era

BACKGROUND

The coronavirus disease 2019 (COVID-19) has affected all countries in the world. Hospital workers are at high risk of mental illness, such as anxiety and depression. Furthermore, they also face many social stresses, such as deterioration of human relations and income reduction. Apart from mental illness, these social stresses can reduce motivation and lead to voluntary absenteeism, which contribute to a collapse of medical systems. Thus, for maintaining medical systems, it is crucial to clarify risk factors for both mental illness and increased social stress among hospital workers. However, little attention has been paid to factors affecting social stress, and thus, we aimed to address this gap.

METHODS

In this cross-sectional survey of 588 hospital workers, the levels of anxiety, depression, and social stress were assessed using the 7-item Generalized Anxiety Disorder scale (GAD-7), 9-item Patient Health Questionnaire (PHQ-9), and Tokyo Metropolitan Distress Scale for Pandemic (TMDP). Multiple regression analyses were conducted to identify the demographic variables affecting these problems.

RESULTS

Older age and female sex were common risk factors for anxiety, depression, and social stress. Moreover, occupational exposure to COVID-19 and hospital staff other than doctors/fewer non-work days were risk factors for increased anxiety and depression, respectively. Furthermore, living with families/others was a risk factor for increased social stress during this pandemic.

CONCLUSION

Our findings could be useful for developing policies and practices to minimize the risk of mental illness and increased social stress among hospital workers, highlighting that attention should be paid to social factors, such as an individual's household situation.

Surgical Classification of Radical Temporal Bone Resection and Transcranial Tympanotomy: A Retrospective Study from the Neurosurgical Perspective

OBJECTIVE

To review the authors' surgical experience with radical temporal bone resection (TBR) with an emphasis on the classification of skull base osteotomy and transcranial tympanotomy (TCT) that is required for middle ear transection.

METHODS

We reviewed the records of 25 patients who underwent radical TBR at our facilities between 2011 and 2020.

RESULTS

The osteotomy line of radical TBR was divided into 3 segments: anterior (A), medial (M), and posterior (P). Each segment was further classified as follows: A1, through the glenoid fossa (1 patient); A2, in front of the glenoid fossa (23 patients); A3, through the greater wing of the sphenoid bone (1 patient); M1, through the middle ear (16 patients); M2, through the inner ear (9 patients); P1, through the mastoid (9 patients); and P2, through the posterior cranial fossa (16 patients). The M segment was significantly associated with operation time and intraoperative blood loss. In all patients with M1 osteotomy, TCT was performed; TCT was classified into superior and far posterior approaches. A superior approach was performed in all 16 patients, whereas the far posterior approach was performed in only 7 patients with both M1 and P2 osteotomy.

CONCLUSIONS

Our newly proposed osteotomy classification of radical TBR is suitable for minute but clinically important adjustment of the osteotomy line. TCT is an indispensable technique for M1 osteotomy; our newly proposed classification expands our understanding of TCT and how to incorporate this technique into radical TBR.

Skull Base Invasion Patterns of Malignant Head and Neck Tumors: A Neurosurgical Perspective

Objective  Craniofacial resection (CFR) and temporal bone resection (TBR) on malignant head and neck tumors (MHNTs) invading skull base require accurate and precise determination of the tumor invasion. We investigated tumor skull base invasion patterns and surgical results in CFR and TBR cases. Methods  We performed either CFR or TBR for 75 selected patients with the possibility of en bloc resection over the period between 2011 and 2018. The medical charts of the selected patients were reviewed. Results  Primary tumor onset site (TOS) groups were: (1) nasal cavity/ethmoid sinus, 20 cases; (2) orbit, 10 cases; (3) maxillary sinus, 28 cases; and (4) external ear/temporomandibular joint, 17 cases. Grades for tumor invasion depth (TID) included: (I) extracranial invasion and skull base bone invasion; (II) extradural invasion; or (III) intradural invasion. Patients in groups 1 and 2 had a significantly higher frequency of grade II and III invasions than patients in groups 3 and 4. The main invasion site was nasal cavity superior wall and ethmoid sinus superior wall for group 1 tumors, orbit superior wall, and lateral skull base sphenoid bone for group 2 and 3 tumors, and lateral skull base temporal bone for group 4 tumors. Positive resection margins represented a significant negative prognostic factor. TID and TOS did not affect skull base margin status. Conclusion  Skull base invasion of MHNTs exhibits certain fixed patterns in sites susceptible to invasion based on the TOS. The frequencies of extradural and intradural invasions differed, indicating the importance for accurate preoperative tumor evaluation.

Comparison of salvage surgery for recurrent or residual head and neck squamous cell carcinoma

Objective

Concomitant chemoradiation therapy is a standard treatment for head and neck cancer. Thus, salvage surgery has become a necessary treatment. The aim of the study was to evaluate the results of salvage surgery by each site of the head and neck, especially the oropharynx, hypopharynx and larynx.

Methods

This was a retrospective, single-institute study. The primary endpoint was overall survival. Secondary endpoints were disease-free survival, the locoregional control rate after salvage surgery, the indication rate for salvage surgery, the reasons for contraindications to salvage surgery, the post-operative complication rate and the predictors of survival.

Results

Three-year overall survival after salvage surgery was 58.8% in the salvage surgery group and 8.59% in the other treatment group (P < 0.0001). Regarding overall survival and disease-free survival after salvage surgery, there was no difference among sites. Regarding locoregional control rate among sites, there was no significant difference. The oropharyngeal cancer group had the lowest rate of salvage primary resection. Surgical margin and local and regional recurrence or residual disease were predictors on univariate and multivariate analyses.

Conclusions

Salvage surgery is effective for recurrent or residual cases after concomitant chemoradiation therapy. For oropharyngeal cancer, local control is important, and for oropharyngeal cancer and hypopharyngeal cancer, distant metastasis is important.

Prospective Evaluation of Health-Related Quality of Life in Patients Undergoing Anterolateral Craniofacial Resection with Orbital Exenteration

Objective  This study was aimed to evaluate health-related quality of life in patients undergoing anterolateral craniofacial resection (AL-CFR) with orbital exenteration (OE) for malignant skull base tumors and to investigate the effects of early psychiatric intervention. Design  Present study is a prospective, observational study. Setting  The study took place at the hospital department. Participants  Twenty-six consecutive patients were selected who underwent AL-CFR with OE at our hospital between 2005 and 2015. Main Outcome Measures  Health-related quality of life was assessed preoperatively and 3, 6, 12, and 24 months after surgery using the Hospital Anxiety and Depression Scale (HADS) and medical outcomes study 8-items Short Form health survey (SF-8). In all cases, psychiatric intervention was organized by the consultation liaison psychiatry team preoperatively and postoperatively. Results  Ten (38.0%) of the 26 patients died and 16 (62.0%) were alive and disease-free at the end of the study. The 3-year overall and disease-free survival rates were 64.9% and 53.3%, respectively. Twenty-one patients (80.8%) developed psychiatric complications after surgery and needed treatment with psychotropic medication. Before surgery, 28% of patients had HADS scores ≥8 for anxiety and 20% had scores ≥8 for depression. Seven of the eight items in the SF-8 were significantly lower than those for the general Japanese population. However, scores for all the SF-8 items gradually improved during postoperative follow-up, reaching approximately 50 points, which is the national standard value, at 2 years after surgery. Conclusions  Craniofacial resection with OE was feasible and well tolerated in patients with malignant skull base tumors who received early psychiatric intervention to decrease the considerable psychological impact of this procedure.

Diagnosis of cervical lymph node metastases in head and neck cancer with ultrasonic measurement of lymph node volume

OBJECTIVE

The purpose of this study was to evaluate the usefulness of ultrasound (US) volume measurement of the cervical lymph nodes for diagnosing nodal metastasis in patients with head and neck cancer using a node-by-node comparison.

METHODS

Thirty-four consecutive patients with head and neck cancer from one tertiary university hospital were prospectively enrolled from 2012 to 2017. Patients with histologically proven squamous cell primary tumors in the head and neck region scheduled to undergo a therapeutic neck dissection were eligible. For each patient, 1-4 target lymph nodes were selected from the planned neck dissection levels. Lymph nodes with thickness >20 mm or in a cluster were excluded. Node-by-node comparisons between the pre-operative US assessment, the post-operative actual measurements and histopathological results were performed for all target lymph nodes. Quantitative measurements, such as three diameters, ratios of the three diameters and volume were analyzed in this study. Lymph node volume was calculated using the ellipsoid formula.

RESULTS

Patients comprised 28 men and 6 women with a mean age of 60.0 years (range, 29-80 years) at the time of surgery. In total, 67 target lymph nodes were analyzed in this study and the thickness ranged from 3.9 to 20.0 mm (mean 8.0 mm). There was a strong correlation between the US volume and post-operative actual volume (ρ = 0.87, p < 0.01). The US volume measured 2156 ± 2156 mm³ for the tumor positive nodes, which was significantly greater than the US volume of 512 ± 315 mm³ for tumor negative nodes (p < 0.01). Significant differences between tumor positive and tumor negative nodes were found in five variables (volume, thickness, major axis, minor axis and ratio of minor axis to thickness) for total lymph nodes. To identify predictors of lymph node metastasis, ROC curves of the US variables of target lymph nodes were compared, of which 4 variables were considered acceptable for predicting the lymph node metastasis: volume (AUC 0.86), thickness (AUC 0.86), major axis (AUC 0.79), and minor axis (AUC 0.79) for total lymph nodes. The optimal cut-off level for US volume in total lymph nodes was found to be 1242 mm³, whereby a 62% sensitivity and 98% specificity was reached (likelihood ratio: 25.2).

CONCLUSION

Pre-operative ultrasonic volume measurement of the cervical lymph nodes was useful for early detection of cervical nodal metastasis in head and neck cancer.

＜Editors' Choice＞ Maxillary sinus carcinoma outcomes over 60 years: experience at a single institution

Advances in the diagnosis and treatment of patients with maxillary sinus carcinoma have improved patient prognosis. This study investigated changes in demographic and clinical characteristics, treatment methods, and outcomes of patients with maxillary sinus carcinomas during three different 10-year periods spanning 60 years at our university hospital. Of the 233 patients with maxillary sinus carcinomas managed at Nagoya University Hospital, 135 were treated between 1951 and 1960 (first period), 35 between 1981 and 1990 (second period), and 63 between 2003 and 2012 (third period). Patient age, sex, TN classifications, treatment methods, and survival rates were compared among patients treated during these time periods. Of the 135, 35, and 63 patients with maxillary sinus carcinomas treated during these time periods, 86 (63.7%), 21 (51.4%), and 48 (76.2%), respectively, were men; 14 (10.4%), six (17.1%), and 14 (22.2%), respectively, were aged ≥70 years; and 135 (100%), 28 (80.0%), and 43 (68.3%), respectively, were treated surgically. The 5-year overall survival rates in patients treated during the first, second, and third periods were 29.7%, 44.3%, and 57.5%, respectively. These findings indicated that advances in the diagnosis and treatment of patients with maxillary sinus carcinoma, including computed tomography and craniofacial resection, have contributed to improvements in patient survival rates.

Swallowing disorder following salvage total pharyngo-laryngo-esophagectomy with free jejunum reconstruction

For recurrent cases or residual cases following concomitant chemo-radiation therapy (CCRT), salvage surgery is a frequently used treatment options. A swallowing disorder is one of the major complications of CCRT. The purpose of the present study was to evaluate the effect of CCRT on swallowing function in patients who underwent salvage total pharyngo-laryngo-esophagectomy (TPLE), and to evaluate the importance of pharyngeal constriction in patients who underwent TPLE. Between 2008 January and 2014 May, 54 patients were treated with salvage TPLE following CCRT or TPLE at the National Cancer Center Hospital East, Chiba, Japan and were included in the present study. A total of 14 patients underwent salvage TPLE following CCRT for recurrence or residual tumor (the salvage TPLE group), and 40 patients underwent TPLE as initial treatment (the TPLE group). The pharyngeal constriction score and the post-swallowing oropharyngeal residue rate were evaluated, and inadequate velopharyngeal closure was assessed by videofluorography. The pharyngeal constriction score of the salvage TPLE group was poorer than that of the TPLE group (P<0.05). The bolus residue in the oropharynx was significantly larger in the salvage TPLE group than in the TPLE group (P<0.05). With regards to inadequate velopharyngeal closure, there was no significant difference between the TPLE group and the salvage TPLE group (P>0.99). The results of the present study indicate that the swallowing function of patients who undergo salvage TPLE may be affected by CCRT.

Computed tomographic assessment of autologous fat injection augmentation for vocal fold paralysis

Objective

To perform a quantitative computed tomography (CT) assessment of short‐ and long‐term outcomes of autologous fat injection augmentation in patients with unilateral vocal fold paralysis.

Study Design

Retrospective case series.

Methods

Twelve patients who had undergone autologous fat injection augmentation for unilateral vocal fold paralysis in our hospital between 2011 and 2015 were enrolled in this study. The autologous fat for injection was acquired from periumbilical subcutaneous tissue and was injected orally using a special‐purpose laryngeal injection needle. To evaluate the injected fat at the follow‐up assessments, CT was performed at several times after surgery in clinical practice. All thin‐section CT images were transferred to a workstation, and the volume of the injected fat was calculated.

Results

Patients comprised 6 men and 6 women with a mean age at the time of surgery of 62.9 years (range, 46–82 years). The actual injected fat volume was 1.1–2.5 ml (mean, 1.6 ml). In seven patients assessed by CT two days after surgery, the average residual rate of the injected fat was 63.9%. The mean residual rates of the injected fat were 30.0% at 3 months, 33.7% at 6 months, 29.2% at 12 months, and 32.0% at 24 months.

Conclusions

Although the injected fat volume decreased within the first three months and the residual rate of the injected fat was 30.0% at three months after injection, the residual fat volume remained at the same level for 24 months after injection.

Level of Evidence

4

Squamous cell carcinoma of the retromolar trigone: Treatment outcomes

OBJECTIVE

Squamous cell carcinoma (SCC) of the retromolar trigone is uncommon, accounting for 1.4% of all oral cancer cases in Japan. Few studies have examined the optimal treatment for this cancer. The aim of this study was to evaluate the outcome of treatment for primary SCC of the retromolar area.

METHODS

We retrospectively analyzed the outcome and prognosis of 45 patients (38 men, 7 women) with SCC of the retromolar trigone who underwent treatment in our department between July 1992 and March 2011.

RESULTS

Mean age was 62.4 years. Clinical stages were: stage I (n=4, 8.9%); stage II (n=10, 22.2%); stage III (n=5, 11.1%); and stage IVa (n=26, 57.8%). Surgical resection was performed in all patients and 6 patients also received postoperative radiotherapy. Reconstructive surgery using free flaps was performed in 38 patients; postoperative complications occurred in 5 of these patients. The 3-year local control rate was 80%, and the 3-year over all survival rates for stage I, II, III, and IV disease were 100%, 80%, 40%, and 49.2%, respectively. Cause of death was the original disease in 23 cases and other diseases in 2 cases. The most common cause of death from the original disease was cervical lymph node metastasis.

CONCLUSION

The presence of cervical lymph node metastasis was a negative prognostic factor. Marginal mandibulectomy may be selected for patients without distinct bone-marrow infiltration.

Preoperative surgical simulation and validation of the line of resection in anterolateral craniofacial resection of advanced sinonasal sinus carcinoma

BACKGROUND

The purpose of this study was to assess the usefulness and accuracy of preoperative 3D virtual simulation of anterolateral craniofacial resection in cases of advanced sinonasal sinus carcinoma.

METHODS

Seven patients with advanced (T4 classification) sinonasal sinus carcinoma who underwent anterolateral craniofacial resection in our hospital between 2011 and 2013 were included in this study. Postsimulation CT images were fused with postoperative CT images and differences between the planned and actual osteotomy were measured in 3 regions of the skull base.

RESULTS

The differences ranged from 0 mm to 5.8 mm (average, 3.1 mm) at the inferior wall of the cavernous sinus, from 0.8 mm to 8.3 mm (average, 3.5 mm) at the inferior wall of the sphenoid sinus, and from 0 mm to 13.6 mm (average, 2.3 mm) in the palatine bone.

CONCLUSION

Preoperative 3D virtual surgical simulation and postoperative feedback can contribute to training for surgeons. © 2016 Wiley Periodicals, Inc. Head Neck 39: 512-519, 2017.

Craniofacial Resection for T4 Maxillary Sinus Carcinoma

Objective

The objective of this study was to clarify the outcomes of craniofacial resection for locally advanced maxillary sinus carcinoma classified as T4 and to present methods for managing cases involving the skull base.

Study Design

Case series with chart review.

Setting

Tertiary university hospital.

Subjects and Methods

We performed anterolateral craniofacial resection in en bloc fashion for locally advanced maxillary sinus carcinoma at stage T4. Participants comprised 40 patients with T4 maxillary sinus carcinoma treated between 1992 and 2011. Surgical outcomes were analyzed retrospectively.

Results

Forty patients with stage T4a (n = 26) or stage T4b (n = 14) were included in this study. Five-year overall and disease-free survival rates for the 40 patients with T4 maxillary sinus carcinoma were 62.7% and 52.6%, respectively. Cavernous sinus involvement correlated significantly with worse prognosis ( P = .012). In 35 cases without cavernous sinus involvement, previous treatment ( P = .017) and positive margins ( P = .019) correlated significantly with worse prognosis, and 5-year overall and disease-free survival rates were 72.4% and 55.3%, respectively.

Conclusion

This study only included cases of locally advanced maxillary sinus carcinoma classified as T4. Considering the advanced stage, our study suggests relatively favorable outcomes and the importance of managing the cavernous sinus in en bloc resections of malignant skull base tumors. Craniofacial resection in en bloc fashion achieved good survival rates.

Effect of clinical symptoms on the indication for selective neck dissection for N0 carcinomas of the parotid gland

Lymph node metastasis is a major prognostic factor in parotid carcinoma, however, the pre-operative diagnosis of occult nodal metastasis is difficult in clinical N0 (cN0) parotid cancer patients. In addition, the indication of neck dissection in T1-3 cN0 patients is controversial. The current study investigated 17 patients with clinical T1-3 cN0 parotid cancer, and analyzed the correlation between patient symptoms/findings and pathological N status/tumor histological grade. In the statistical analysis, pain was found to significantly correlate with neck metastasis. Furthermore, cN0-staged patients without pain exhibited no neck metastasis. However, no significant correlation was identified between patient symptoms or findings and histological grade. These results indicate the possibility that selective neck dissection can be omitted for T1-3 cN0-staged patients without pain.

Analysis of the human intestinal microbiota from 92 volunteers after ingestion of identical meals

The intestinal microbiota composition of 92 volunteers living in Japan was identified following the consumption of 'identical meals' (1,879 kcal/day) for 3 days. When faecal samples were analysed by terminal restriction fragment length polymorphism with several primer-restriction enzyme systems and then clustered, the patterns could be divided into 2 clusters. Contribution tests and partition modelling showed that OTU211 of the 35f-MspI system and OTU237 of the 35f-AluI system were key factors in the distribution of these groups. However, significant differences among these groups in terms of body mass index and age were not observed.

18F-FDG-PET/CT predicts survival in hypopharyngeal squamous cell carcinoma

OBJECTIVES

We investigated the relationship between overall survival of patients and pretreatment [(18)F]-2-fluorodeoxyglucose ((18)F-FDG) uptake, assessed by positron emission tomography combined with computed tomography (PET/CT) in hypopharyngeal squamous cell carcinoma.

METHODS

Thirty-one patients who were newly diagnosed as resectable hypopharyngeal squamous cell carcinoma underwent pretreatment (18)F-FDG-PET/CT. We used the maximum standardized uptake value (SUVmax) as (18)F-FDG uptake. Overall survival rate was calculated by the Kaplan-Meier method.

RESULTS

The median SUVmax was 11.53 (range 2.49-22.33). Patients with SUVmax ≥ 13 significantly exhibited shorter overall survival in univariate analysis (p < 0.01). Moreover, by Cox proportional hazards model of multivariate analysis, SUVmax ≥ 13 was a significant prognostic factor independent of clinical T and N classification, and treatment group (p < 0.02).

CONCLUSIONS

These results suggested that SUVmax obtained by pretreatment (18)F-FDG PET/CT assessment is an important prognostic factor in patients with hypopharyngeal squamous cell carcinoma.

REG Iα is a biomarker for predicting response to chemotherapy with S-1 plus cisplatin in patients with unresectable stage IV gastric cancer

Background:

The regenerating gene Iα (REG Iα) is involved in gastric carcinogenesis as an antiapoptotic factor. Therefore, we investigated whether REG Iα confers resistance to chemotherapeutic drugs in gastric cancer (GC) cells and whether REG Iα expression is useful for predicting the response to chemotherapy and outcome in patients with GC.

Methods:

A total of 70 patients with unresectable stage IV GC received first-line chemotherapy with S-1 and cisplatin (S-1/CDDP). The expression of REG Iα was evaluated immunohistochemically using biopsy samples obtained before chemotherapy, and its relationship to clinicopathological parameters was analysed statistically. The effects of REG Iα gene induction on resistance to 5-FU or CDDP treatment were examined by cell survival assay and flow cytometry.

Results:

Of the 70 patients with unresectable stage IV GC, 19 (27%) were positive for REG Iα expression. The expression of REG Iα was independently predictive of poorer progression-free and overall survival in such patients (hazard ratio (HR) 2.46; P=0.002 and HR 1.89; P=0.037, respectively). The gene induction of REG Iα conferred resistance to cell death induced by 5-FU or CDDP in GC cells.

Conclusion:

In patients with stage IV GC, REG Iα, which confers resistance to chemotherapeutic drugs in GC cells, is a potential biomarker for predicting resistance to S-1/CDDP treatment.

Feasibility of 2nd generation STS retinal prosthesis in dogs

We developed a 2(nd) generation suprachoroidal transretinal stimulation (STS) system with a 49 channel electrode array and implanted in 2 dogs. One month after surgery, all electrodes were functioning and the ocular fundus was normal in both dogs. The results indicate the 2(nd) generation STS retinal prosthesis is feasible and can be considered for clinical use.

Oral administration of milk fermented with Lactococcus lactis subsp. cremoris FC protects mice against influenza virus infection

AIMS

To evaluate the protective effects of oral administration of milk fermented with a Lactococcus strain against influenza virus (IFV) infection in a mouse model.

METHODS AND RESULTS

Milk fermented with exopolysaccharide-producing Lactococcus lactis subsp. cremoris (L. cremoris) FC was orally administered to BALB/c mice for 12 days. Mice were intranasally infected with IFV A/New Caledonia/20/99 (H1N1) on day 8, and survival was determined for 14 days after IFV infection. Survival rate and body weight loss after IFV infection in the L. cremoris FC fermented milk-administered group were significantly improved compared with those in the control group. In the unfermented milk-administered group, survival rate was not improved, whereas body weight loss was slightly improved compared with that in the control group. The mean virus titre in the lung of the L. cremoris FC fermented milk-administered group 3 days after infection was significantly decreased compared with that in the control group.

CONCLUSIONS

These results suggest that oral administration of milk fermented with L. cremoris FC protects mice against IFV infection.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results demonstrate that oral administration of milk fermented with exopolysaccharide-producing Lactococcus strains might protect host animals against IFV infection.

Identification of Cancer Stem Cells Derived From a Canine Lung Adenocarcinoma Cell Line

Accumulating evidence supporting the cancer stem cell (CSC) hypothesis is based on the finding that tumors contain a small population of self-renewing cells that generate differentiated progeny and thereby contribute to tumor heterogeneity. CSCs are reported to exist in several human cancers, yet only a few reports demonstrate the existence of CSCs in primary lung cancer in dogs. In this study, the authors established a cancer cell line derived from a canine primary lung adenocarcinoma and identified a side population (SP) of cells that displayed drug-resistant features. To confirm the characteristics of these SP cells, the authors investigated the tumorigenicity of the cells in vivo by using a nude mouse xenograft model. Only 100 SP cells were able to give rise to new tumors, giving a 10-fold enrichment over the main population (MP) of cells, suggesting that these cells have the cancer-initiating ability of CSCs. Further studies characterizing CSCs in canine lung adenocarcinoma might contribute to the elucidation of the mechanisms of tumorigenesis and to the establishment of novel therapeutic strategies.