Anatomical variations in the superficial venous system of the neck: an image-based study using contrast-enhanced computed tomography.

PURPOSE: The superficial venous system (SVS) of the neck receives blood from the face and oral cavity. The SVS comprises the anterior jugular vein (AJV), external jugular vein (EJV), and facial vein (FV). Comprehensive knowledge of the normal anatomy and potential variations in the venous system is valuable in surgical and radiological procedures. This study aimed to update the anatomic knowledge of the SVS using a radiographic approach, which is a beneficial data source in clinical practice. METHODS: Contrast-enhanced computed tomography images of the neck of patients with head and neck cancer treated between 2017 and 2020 were retrospectively evaluated. Each side of the neck was counted separately. A total of 302 necks of 151 patients were enrolled in this study. RESULTS: The medial AJV was absent in 49.7% (75/151) of the patients on the left side, which was significantly greater than the 19.2% (29/151) on the right (p < 0.001). The left AJV drained into the right venous system in 6.6% (10/151) of the necks. In 48.3% (146/302) of the necks, the FV did not flow into the internal jugular vein but rather into the EJV or AJV; these findings were significantly more frequent than those reported in previous studies. The diameters of the veins were significantly larger when they received blood from the FV than when they were not connected to the FV. CONCLUSION: These findings indicate that the AJV has a rightward preference during its course. The course of the FV is diverse and affects the diameter of connected veins.

Clinicopathological Characteristics and Survival Outcomes of Patients with Buccal Squamous Cell Carcinoma: Results of a Multi-Institutional Study.

Background and Objectives: To investigate clinicopathological characteristics and survival outcomes of patients with buccal cancer in Japan. Materials and Methods: This study was conducted using a database of 1055 patients with oral cancers treated between 2010 and 2017 at 12 institutions in Japan. Ninety-two patients (8.7%) with primary buccal cancer were extracted and clinicopathological characteristics and survival outcomes were compared between patients with buccal cancers and patients with other oral cancers. Results: Ages were significantly higher in the patients with buccal cancer (73 years old vs. 69 years old). Buccal cancer had less advanced cT stage and cN stage than other oral cancers. Overall 5-year survival (OS) was 80.6%, and recurrence-free 5-year survival (RFS) of buccal cancers was 67.8%, and there were no significant differences in survival compared with other oral cancers in terms OS or RFS (5y-OS: 82.5%, 5y-RFS: 74.4%). However, patients with stage IV buccal cancer showed poorer prognosis in terms of OS and RFS compared with the same stage patients with other oral cancer. Advanced T stage was the only factor independently associated with both OS and RFS of patients with buccal cancer in this study. Conclusions: Postoperative radiotherapy or chemoradiotherapy should be considered to improve survival outcome of buccal cancer patients, especially for the patients with advanced primary site disease or a higher cancer stage.

Lingual Lymph Node Metastases as a Prognostic Factor in Oral Squamous Cell Carcinoma-A Retrospective Multicenter Study.

Backgrounds and Objectives: The epidemiology and prognostic role of lingual lymph node (LLN) metastasis in patients with oral squamous cell carcinoma (OSCC) remain unclear. Here, we aimed to analyze the clinicopathological features, risk factors, and prognostic role of LLN metastasis in patients with OSCC. Materials and Methods: In total, 945 patients with OSCC were retrospectively analyzed. Clinicopathological features were compared between patients with and without LLN metastasis. The risk factors of LLN metastasis and its effects on survival outcomes were evaluated using multi-variate analysis. Results: LLN metastasis was noted in 67 patients (7.1%). Habitual alcohol consumption and clinical neck node metastasis were independent risk factors for LLN metastasis. LLN metastasis was an independent prognostic factor for disease-free and overall survival, although LLN dissection did not improve survival outcomes. Conclusion: LLN metastasis is an independent adverse prognostic factor. Further prospective studies are needed to fully assess the extent of LLN dissection required in OSCC patients.

Speech Discrimination in Real-World Group Communication Using Audio-Motion Multimodal Sensing.

Speech discrimination that determines whether a participant is speaking at a given moment is essential in investigating human verbal communication. Specifically, in dynamic real-world situations where multiple people participate in, and form, groups in the same space, simultaneous speakers render speech discrimination that is solely based on audio sensing difficult. In this study, we focused on physical activity during speech, and hypothesized that combining audio and physical motion data acquired by wearable sensors can improve speech discrimination. Thus, utterance and physical activity data of students in a university participatory class were recorded, using smartphones worn around their neck. First, we tested the temporal relationship between manually identified utterances and physical motions and confirmed that physical activities in wide-frequency ranges co-occurred with utterances. Second, we trained and tested classifiers for each participant and found a higher performance with the audio-motion classifier (average accuracy 92.2%) than both the audio-only (80.4%) and motion-only (87.8%) classifiers. Finally, we tested inter-individual classification and obtained a higher performance with the audio-motion combined classifier (83.2%) than the audio-only (67.7%) and motion-only (71.9%) classifiers. These results show that audio-motion multimodal sensing using widely available smartphones can provide effective utterance discrimination in dynamic group communications.

Survival in patients with parotid gland carcinoma - Results of a multi-center study.

BACKGROUND: Parotid gland carcinoma is a rare malignancy, comprising only 1-4% of head and neck carcinomas; therefore, it is difficult for a single institution to perform meaningful analysis on its clinical characteristics. The aim of this study was to update the clinical knowledge of this rare disease by a multi-center approach. METHODS: The study was conducted by the Kyoto University Hospital and Affiliated Facilities Head and Neck Clinical Oncology Group (Kyoto-HNOG). A total of 195 patients with parotid gland carcinoma who had been surgically treated with curative intent between 2006 and 2015 were retrospectively reviewed. Clinical results including overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), local control rate (LCR), regional control rate (RCR), and distant metastasis-free survival (DMFS) were estimated. Univariate and multivariate analyses were performed to identify prognostic factors. RESULTS: The median patient age was 63years old (range 9-93years), and the median observation period was 39months. The OS, DFS, DSS, LCR, RCR, and DMFS at 3years were 85%, 74%, 89%, 92%, 88%, and 87%, respectively. Univariate analysis showed age over 74, T4, N+, preoperative facial palsy, high grade histology, perineural invasion, and vascular invasion were associated with poor OS. N+ and high grade histology were independent factors in multivariate analysis. In subgroup analysis, postoperative radiotherapy was associated with better OS in high risk patients. CONCLUSION: Nodal metastases and high grade histology are important negative prognostic factors for OS. Postoperative radiotherapy is recommended in patients with advanced high grade carcinoma.

Thyroid Lobectomy Under Local Anesthesia Before Lung Transplantation Owing to Diffuse Panbronchiolitis: A Case Report.

We herein report a case of thyroid lobectomy performed under local anesthesia for thyroid cancer in a patient who was at a high risk for general anesthesia due to diffuse panbronchiolitis. Although thyroid surgery has been performed in the past under local anesthesia in low-risk patients, thyroid surgery is now rarely performed under local anesthesia. If they are performed, thyroid surgery under local anesthesia is usually performed under monitored anesthesia care; sedation is considered safe and does not cause discomfort to patients. The present patient's respiratory function was poor, raising concerns that once intubated, extubation may not be possible because of the potential deterioration of respiratory function caused by the suppression of spontaneous breathing. Therefore, sedatives were avoided to maintain spontaneous breathing as much as possible. In such high-risk patients, additional care is required to ensure that the procedure is completed with minimal discomfort from pain or dyspnea. Maintaining a slightly upright position and raising the anesthesia screen are necessary to ensure a large space in front of the patient's face. In addition, an appropriate skin incision should be made to obtain a wide field of vision, and local anesthetic injections should be administered frequently to preemptively counter pain. Atropine sulfate was administered to reduce salivation and swallowing. Energy devices effectively reduced blood loss and operative time. Controlling intraoperative pain and bleeding is important, and the methods and techniques are also beneficial in surgery under general anesthesia.

Modified method for tracheoesophageal fistula closure in intractable cases.

OBJECTIVE: Tracheoesophageal puncture (TEP) is one of the most established methods for voice reacquisition following total laryngectomy. The most difficult complication following TEP is the management of saliva leakage or secretion into the trachea due to TE fistula enlargement. In this study, we devised a new strategy to close TE fistulas and confirmed its safety and effectiveness. METHODS: Skin incision: If the tracheal mucosa around the voice prosthesis appears intact and normal, an arcuate incision, from 10 to 2 o'clock, is made on the skin 5 mm superior to the edge of the stoma. However, if the surrounding tracheal mucosa is fragile because of leaking, the incision is made on the superior edge of the stoma, with later reconstruction of the posterior tracheal wall. Separation of the trachea and esophagus: If the esophagotracheal spatium appears normal and is easy to dissect, the connective pipes can be found easily. After cutting the pipe, a ligature alone is sufficient for the tracheal side; however, the esophageal wall is closed with Gambee sutures. If the esophagotracheal spatium is compromised and the posterior tracheal wall is fragile (due to saliva leakage), we remove the posterior wall and reconstruct the area using the superior skin flap. We performed our novel method on four patients with intractable conditions; postradiotherapy for laryngeal cancer, total pharyngo-laryngo-esophagectomy (TPLE) with jejunum reconstruction, TPLE with gastric lifting reconstruction, and in a patient who underwent cervicothoracic incisional drainage for descending necrotizing mediastinitis. RESULTS: None of the cases showed postoperative leakage from the fistula, and oral intake was resumed without difficulty. CONCLUSION: This study showed that this strategy based on TE fistula conditions is effective even in difficult-to-treat cases.

Mucosal melanoma of the head and neck: a retrospective analysis of 34 cases in Japan.

PURPOSE: Mucosal melanoma of the head and neck (MMHN) is a rare condition. This study aimed to investigate oncological outcomes of surgical intervention in patients with MMHN. MATERIALS AND METHODS: The study included 34 patients with MMHN who underwent surgical resection as initial treatment at 10 institutions in Japan between July 2005 and June 2015. Results: The 5-year overall survival (OS), local control rate (LCR), disease-free survival (DFS), and disease-specific survival (DSS) rates were 48.7%, 53.4%, 32.4%, and 55.1%, respectively. Based on multivariate analysis, no independent prognostic factors for the 5-year OS and DSS were found. Based on univariate analysis, the 5-year LCR was worse in patients with lesions in the nasal cavity and paranasal sinuses than in the oral cavity and pharynx. However, no differences in oncological outcomes were identified in relation to primary sites, and postoperative radiotherapy (PORT) and adjuvant systemic therapy did not contribute to improvements in the 5-year OS. CONCLUSIONS: No independent prognostic factors for the 5-year OS or DSS were identified. Regional or distant recurrences are often identified, regardless of local control with surgical resection. Difficult control of MMHN with conventional therapeutic strategies, such as surgical intervention, PORT, and systemic therapy, has been suggested.

A multi-institutional retrospective study of 340 cases of sinonasal malignant tumor.

OBJECTIVE: Sinonasal malignant tumors (SNMT) are relatively rare among head and neck malignant tumors. Most are squamous cell carcinomas, and malignant melanomas, olfactory neuroblastomas, adenoid cystic carcinomas, sarcomas, and others also occur. The most common primary site of nasal sinus squamous cell carcinoma is the maxillary sinus. In recent years, a decrease in incidence of maxillary sinus squamous cell carcinoma (MSSCC) has been reported along with a decrease in the incidence of sinusitis. MSSCC is treated with a combination of surgery, radiation, and chemotherapy. Treatment decisions are made according to the progression of the disease, the patient's general condition, and the patient's own wishes. There are variations in treatment policies among facilities due to the specialty of staff and cooperation with other departments at each facility. We conducted a multi-institutional retrospective study to compare outcomes by treatment strategy. METHODS: In this study, 340 patients with SNMT who were treated at 13 Hospitals (Head and Neck Oncology Group (Kyoto-HNOG) ) during the 12-year period from January 2006 to December 2017 were included. There were 220 patients with squamous cell carcinoma, 32 with malignant melanoma, 21 with olfactory neuroblastoma, and 67 with other malignancies. Of the squamous cell carcinomas, 164 were of maxillary sinus origin. One hundred and forty cases of MSSCC that were treated radically were included in the detailed statistical analysis. RESULTS: There were 5 cases of cStage I, 9 cases of cStage II, 36 cases of cStage III, 74 cases of cStage IVa, and 16 cases of cStage IVb. There were 92 cases without clinical lymph node metastasis (cN(-)) and 48 cases with clinical lymph node metastasis(cN(+)). Primary tumors were treated mainly by surgery in 85 cases (Surg) and by radical radiation therapy (with or without chemotherapy) of 6-70 Gy in 55 cases(non-Surg). The 5-year overall/disease-free survival rate (OS/DFS) for MSSCC was 65.1%/51.6%. Old age, renal dysfunction, and clinical T progression were independent risk factors for OS, and renal dysfunction was an independent risk factor for DFS. In cN(-) patients, OS and DFS were significantly better in Surg group than in non-Surg group. In cN(+) patients, there was no significant difference in OS and DFS between Surg and non-Surg groups. CONCLUSION: For patients with MSSCC without lymph node metastasis, aggressive surgery on the primary tumor contributes to improved prognosis.

Palatal mucoperiosteal flap for oro-nasal fistula following maxillectomy for maxillary sinus cancer.

OBJECTIVES: This study aimed to describe the technique and clinical outcomes of using a palatal mucoperiosteal flap for oro-nasal fistula closure following resection of maxillary sinus cancer. METHODS: The study was conducted with the permission of the internal review board of the Japanese Red Cross Wakayama Medical Center. Five consecutive cases from 2016 to 2020 of surgically treated maxillary sinus cancer in which the oro-nasal fistulas were closed using a palatal mucoperiosteal flap were retrospectively reviewed. RESULTS: Following tumor resection, the oro-nasal fistula was closed using a palatal mucoperiosteal flap. Complete separation of the oral and nasal cavities was achieved in four patients. Oral intake was resumed within two weeks in four patients. All the patients were able to eat foods similar to those in the preoperative period. Their postoperative speech function was excellent, with no difficulty in communicating with others. CONCLUSION: In the selected cases of maxillary sinus cancer, preservation of the palatal mucosa and closure of an oro-nasal fistula using a palatal mucoperiosteal flap was possible with reasonable outcomes for swallowing and speech functions. The use of this local flap is recommended as a minimally invasive procedure that can be performed especially in patients with limited physiological reserves which preclude free flap reconstruction.

Characteristics of oral squamous cell carcinoma focusing on cases unaffected by smoking and drinking: A multicenter retrospective study.

BACKGROUND: Some oral squamous cell carcinoma (OSCC) cases are unaffected by smoking or drinking. This study aimed to clarify distinctive groups among OSCC patients and examine the characteristics of multiple primary carcinomas (MPCs). METHODS: We analyzed data from 970 patients. The patients were divided into three groups: all individuals <45 years (<45 y), smokers/drinkers ≥45 years (SD ≥45 y), and non-smokers/non-drinkers ≥45 years (NSND ≥45 y). RESULTS: Tongue cancers were more common in the <45 y group than in the other groups (p < 0.001). The NSND ≥45 y group was significantly older and more likely to be female than the SD ≥45 y group (p < 0.001). MPCs in the upper aerodigestive tract were more common in men and smokers/drinkers, whereas women were at risk for multiple primary OSCCs (p = 0.022). CONCLUSIONS: The "young tongue" and "elderly female" subgroups and characteristics of MPCs suggest carcinogenic factors of OSCC other than smoking and drinking.

Two rare TSH receptor amino acid substitutions in toxic thyroid adenomas.

Toxic adenoma and toxic multinodular goiter (TMNG) are common causes of hyperthyroidism in iodine-deficient regions, but they are relatively rare in iodine-sufficient regions, including Japan. Constitutive activating mutations of the thyroid stimulating hormone receptor (TSHR) gene and adenylate cyclase-stimulating G α protein (GNAS) gene are frequent in these thyrotoxic disorders. Here we report two cases of rare TSHR gene mutations in Japanese thyrotoxicosis patients. In Case 1, we observed multiple toxic nodules with thyrotoxicosis, and in Case 2, we detected a solitary toxic nodule in an 8-year-old girl. In both cases, ultrasonography showed thyroid nodules and scintigraphy revealed increased uptake. Total thyroidectomy was performed for Case 1 and a hemi-thyroidectomy was performed for Case 2. Genetic analysis of the resected tissues revealed an I568F mutation in Case 1 and a S281I mutation in the TSHR gene in Case 2. The I568F mutation was located in the second extracellular loop, and the S281I mutation was located in the N-terminal extracellular domain of the TSH receptor. In Case 1, the mutation was restricted to the largest nodule, and was not detected in other functioning nodules or non-nodule thyroid tissue. Bi-allelic expression of the TSHR gene was confirmed by reverse transcription-polymerase chain reaction in both tumors. Both the I568F and S281I mutations were studied previously in vitro, and were revealed to cause basal activation of the protein kinase A pathway. Case 1 represents the second reported case of an I568F mutation and Case 2 represents the third reported case of an S281I mutation.

Real-world 2-year long-term outcomes and prognostic factors in patients receiving nivolumab therapy for recurrent or metastatic squamous cell carcinoma of the head and neck.

OBJECTIVE: Real-world outcomes and prognostic factors in Japanese patients receiving nivolumab therapy for recurrent or metastatic head and neck carcinoma (RMHNC) with an observation period of 1 year have been previously reported. The 1-year follow-up data have been subsequently accumulated, and the long-term real-world outcomes have been analyzed. This study aimed to investigate the 2-year long-term outcomes and prognostic factors associated with the response to nivolumab. METHODS: This was a multi-institutional retrospective study. In total, 88 RMHNC Japanese patients with squamous cell carcinoma who received nivolumab between May 2017 and May 2018 were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), and best overall response (BOR) were evaluated. Univariate and multivariable analyses were performed to identify the prognostic factors. RESULTS: The median follow-up periods for monitoring OS and PFS were 73.1 and 48.1 weeks, respectively. The median OS was 74.1 weeks, and the 2-year survival rate was 33.4%. The median PFS was 18.5 weeks, and the 2-year PFS rate was 22.5%. The BOR rate was 10.2%, 19.3%, 25.0%, and 44.3% in patients who achieved complete response, partial response, stable disease, and progressive disease (PD), respectively. Among the 88 patients with RMHNC, a total of 40 immune-related adverse events (irAEs) were reported in 30 patients. Four patients continued nivolumab, while 84 patients discontinued nivolumab at the data cut-off date. The most common reason for discontinuation was PD in 61 patients, irAEs in 14 patients, and patients' wishes in 7 patients. Of the 61 patients who discontinued nivolumab because of PD, 28 patients received subsequent treatment. Statistical analyses revealed radiotherapy history, performance status, platinum-refractory carcinoma, irAEs, age, and post-nivolumab treatment as the important prognostic factors associated with OS in patients with RMHNC, and the magnitude of BOR was significantly associated with OS. Additionally, patients with subsequent treatment, including molecular targeted therapy and/or chemotherapy, had significantly prolonged OS compared to patients without subsequent treatment in cases with nivolumab discontinuation because of PD. CONCLUSION: These findings could be a useful guide for future treatment strategies for head and neck carcinoma. Considering the limitations of our cohort, further larger-scale studies with long-term follow-up are needed to substantiate the results of this study.

Functional results of Reinke's edema surgery using a microdebrider.

OBJECTIVES: We evaluated the functional results of Reinke's edema surgery using a microdebrider. METHODS: In this prospective nonrandomized study from 2004 through 2008, functional surgery using a microdebrider was performed on patients with severe Reinke's edema. Comparisons were conducted for preoperative and postoperative phonatory function using both subjective grade (G), roughness (R), breathiness (B), asthenia (A), and strain (S) scoring and objective Multi-Dimensional Voice Program parameters. Statistical analysis was done by paired t-test, and a p value of less than 0.05 was considered significant. RESULTS: Seventeen patients were enrolled in this study, with a median age of 56 years and a median observation period of 129 days. The male-to-female ratio was 1 to 2.4. No major complications were observed in the perioperative period. Significant improvement was observed in the subjective values of G, R, B, and S. Improvement was also observed in the fundamental frequency, pitch perturbation quotient, and amplitude perturbation quotient calculated by the Multi-Dimensional Voice Program. CONCLUSIONS: The microdebrider is a useful tool in functional surgery for severe Reinke's edema and gives good functional outcomes. Surgeons can swiftly complete the key steps of removing pathological submucosal tissue and preserving the normal epithelium with an excellent surgical view.

A retrospective multicenter study of sublingual gland carcinoma in Japan.

OBJECTIVE: Salivary gland carcinoma is rare among head and neck cancers. Sublingual gland carcinoma, a type of salivary gland carcinoma, is even rarer; therefore, the number of cases at a single institute is too small for sufficient evaluation of tumor characteristics. We conducted a multicenter, retrospective analysis of sublingual gland carcinomas in patients who visited 12 institutions associated with the Kyoto Hospital and Affiliated Facilities Head and Neck Clinical Oncology Group. METHODS: Thirteen previously untreated patients who visited the institutions between 2006 and 2015 were enrolled. The overall survival (OS) and disease-free survival (DFS) rates for all patients and by disease stage were analyzed. Statistical analyses were performed for all patients with respect to disease stage. RESULTS: Eight of thirteen patients were diagnosed with adenoid cystic carcinoma on pathological study. A significant difference in OS rate was observed between patients with Stage I-III and Stage IV disease; however, the difference in DFS rate by disease stage was not significant. CONCLUSION: Stage IV disease was identified as a poor prognostic factor in patients with sublingual gland carcinoma. However, even patients with Stage I-III disease experienced relatively short DFS. Distant metastasis is a serious problem among patients with sublingual gland carcinoma.

Real-World Outcomes and Prognostic Factors in Patients Receiving Nivolumab Therapy for Recurrent or Metastatic Head and Neck Carcinoma.

Recently, a global phase III study demonstrated that nivolumab markedly improved patient outcomes in recurrent or metastatic head and neck carcinoma (RMHNC). However, the efficacy of nivolumab in patients who are ineligible for clinical trials is unknown. We investigated nivolumab efficacy in real-world patients and prognostic factors associated with the response to nivolumab. This study was conducted at 11 institutes associated with Kyoto University and its Affiliated Hospitals-Head and Neck Oncology Group. In total, 93 patients with RMHNC who received nivolumab between May 2017 and May 2018 were retrospectively reviewed. Objective response rate (ORR), overall survival, and progression-free survival (PFS) were evaluated. Univariate and multivariate analyses were performed to identify prognostic factors. The ORRs in patients with squamous cell carcinoma (SCC) and non-SCC were 21.8% and 0%, respectively. In patients with SCC and non-SCC, the 1-year PFS rates were 28.7% and 8.9%, respectively. The hazard ratio (HR) for risk of PFS events (SCC versus non-SCC) was 2.28 (95% confidence interval: 1.21-4.1; log-rank p = 0.007). Univariate and multivariate analyses revealed radiotherapy history, platinum-refractory carcinoma, and treatment-related adverse events (TRAEs) as important prognostic factors associated with PFS in patients with SCC. In a real-world setting, non-SCC and platinum-refractory carcinoma were associated with a poorer prognosis, and a history of radiotherapy to the primary tumor, and the occurrence of TRAEs were associated with a better prognosis. These findings could be useful for clinicians and patients when selecting a treatment strategy.

Combined transoral-transhyoid endoscopic approach for hypopharyngeal cancer.

Endoscopic transoral surgery for hypopharyngeal cancer is an effective treatment option to avoid invasive open surgery or chemoradiation. Here we describe the case of a 66-year-old patient with cT2N0M0 pyriform sinus cancer whom we treated using a transoral-transhyoid endoscopic approach. Using this approach, a transhyoid route was created in addition to the transoral route and used to extirpate the tumor. En bloc resection of the tumor was completed without difficulty. A combined transoral-transhyoid approach is a useful surgical option for treatment of selected patients with hypopharyngeal cancer. This technique is straightforward to perform and can be used as a backup technique in endoscopic transoral surgery. Also, more complicated lesions can be resected by this approach than by a single-route transoral approach.

Sensory preservation in neck dissection: outcomes of a sub-sternocleidomastoid approach.

OBJECTIVE: Cutaneous anesthesia in early postoperative period is common after neck dissection even if the cervical nerve (CN) rootlets are preserved. The aim of this study was to evaluate if the preservation of the terminal branches of CNs using sub-sternocleidomastoid (SCM) approach combined with medially placed skin incision can prevent early postoperative anesthesia. MATERIAL AND METHODS: A retrospective chart review was performed on 129 neck dissections in 87 head and neck cancer patients. RESULTS: The early postoperative sensory preservation rates for the ear tab, submandibular, lateral neck, and sub-clavicular areas of CN rootlet-preserved necks (n = 86) were 75.6%, 20.9%, 74.4%, and 86.0%, respectively, compared with 37.2%, 2.3%, 2.3%, and 4.7%, respectively, in CN rootlet-resected necks (n = 43). In CN rootlet-preserved necks, the sub-SCM approach (n = 54) showed 81.5%, 27.8%, 92.6%, and 94.4% preservation rates, respectively, compared with 65.6%, 9.4%, 43.8%, and 71.9%, respectively, using the conventional subplatysmal approach (n = 32). The rates were significantly better in the submandibular, lateral neck, and sub-clavicular areas after sub-SCM approach. CONCLUSIONS: Preservation of CN rootlets is a required element for sensory preservation in neck dissection. The sub-SCM approach can effectively prevent early postoperative cutaneous anesthesia following CN-preserving neck dissection.

Adenoid cystic carcinoma of the head and neck: a retrospective multicenter study.

BACKGROUND: Adenoid cystic carcinoma of the head and neck (ACCHN) is rare and difficult to study effective treatment at one institute. Our aim is to identify prognostic factors for this disease by conducting a multicenter study at 11 institutions in Japan. METHODS: A retrospective multicenter study of ACCHN was performed. One hundred and three patients were identified between 2006 and 2015. The overall survival (OS) rate for all patients was calculated, and OS, locoregional control (LRC) rate, or no distant metastasis (NDM) rate was calculated for patients in that the surgery was performed without distant metastasis (DM). Statistical analyses were performed. RESULTS: A significant difference with multivariate analysis was observed in patients in sublingual glands, stage IV and the use of radiation therapy ≥60Gy (sufficient RT) in OS for all patients. A significant difference was observed in the use of sufficient postoperative RT in the OS and the LRC rate, and in pathological surgical margins in the NDM rate. CONCLUSION: Sublingual glands or stage IV was a poorer, and sufficient RT was a better prognostic factor for ACCHN. Sufficient RT was effective to prevent local recurrence after surgical resection. Positive surgical margins caused an increase in DM.

Unknown primary squamous cell carcinoma of the head and neck: retrospective analysis of 80 cases.

OBJECTIVES: The management of patients with cervical metastasis in head and neck cancer of unknown primary (HNCUP) remains controversial. This current multicenter retrospective study investigated the treatment outcomes of patients with HNCUP. METHODS: The study included patients who were treated curatively at 12 institutions in Japan from January 2006 to December 2015. RESULTS: Eighty patients with HNCUP were included. The median follow-up period was 34 months. The three-year overall survival (OS), disease-specific survival (DSS), regional relapse-free survival (RRFS), local progression-free survival (LPFS), and distant metastasis-free survival (DMFS) rates were 72.5%, 80.3%, 74.0%, 89.7%, and 86.9%, respectively. Nodal status was a significant factor for OS, DSS, RRFS, and DMFS; and extracapsular extension (ECE) was significant for OS and DSS. There was a distinct difference between the survival rates of patients with N1-2a and N2b-3 disease. RT was a significant positive factor for LPFS (3-year LPFS, RT 93.0% vs. no RT 83.0%, p = .043). CONCLUSIONS: For N2a as well as N1 disease without ECE, a single treatment modality, including ND or RT alone is acceptable. When ND alone is performed, thorough monitoring should be continued during follow-up to identify the emergence of the primary lesion.