A 14-year nationwide epidemiological analysis of delayed endolymphatic hydrops in Japan.

BACKGROUND: Delayed endolymphatic hydrops (DEH) is an inner ear disease that causes recurrent vertigo in the ipsilateral ear or fluctuating hearing in the contralateral ear due to endolymphatic hydrops secondary to preceding deafness. There are few reports of large, multicentre studies investigating the clinical-epidemiological characteristics of DEH. OBJECTIVE: This study aimed to clarify the characteristics of DEH in Japan. METHODS: Clinical data on 662 patients with DEH were analysed by nationwide, multicentre surveys conducted by the Peripheral Vestibular Disorders Research Group of Japan. RESULTS: The proportion of ipsilateral DEH (IDEH) was slightly higher than that of contralateral DEH (CDEH) at 55.4%. The time delay between onset of precedent deafness and onset of DEH was significantly longer for CDEH than for IDEH. The most common cause of precedent deafness was a disease of unknown cause with onset in early childhood (33.1%). Epidemiological characteristics were not significantly different between CDEH with and without vertigo. CONCLUSION: DEH appearing to be caused by viral labyrinthitis has a high rate of onset within 40 years of precedent deafness. Clinical and epidemiological characteristics of IDEH, CDEH with vertigo, and CDEH without vertigo were very similar. SIGNIFICANCE: The clinical-epidemiological characteristics of DEH in Japan were clarified.

Enhanced methamphetamine-induced conditioned place preference in risk-taking rats.

Patients with psychiatric disorders, such as gambling and substance use, tend to exhibit maladaptive decision-making. In this study, we assessed individual differences in risk-taking behaviors using a rat gambling task (GT) and investigated the relationship between risk-taking behaviors and vulnerability to drug dependence using methamphetamine (METH)-induced conditioned place preference (CPP). In the GT using a radial arm maze, male Long-Evans rats were trained to choose one of three choice arms (a low-risk/low reward (L-L), a high-risk/high reward (H-H), and an empty arm) in 16 trials per day for 14 days. METH-induced CPP consisted of 6 sessions: habituation, conditioning, preference test (Test I), extinction, extinction test (Test II), and reinstatement test (Test III). Results demonstrated that the percentage of choosing the H-H arm was significantly positively correlated with the percentage of time spent in the METH-paired compartment in the preference test, but not with the extinction and reinstatement tests, suggesting that risk-taking rats are more vulnerable to drug dependence.

Carbon-ion radiotherapy combined with chemotherapy for head and neck mucosal melanoma: Prospective observational study.

This study aimed to evaluate the efficacy of carbon-ion radiotherapy in combination with chemotherapy using dacarbazine, nimustine, and vincristine (DAV therapy) in mucosal melanoma. Twenty-one patients with clinically localized mucosal melanoma of the head and neck were enrolled. The primary endpoint was 3-year overall survival (OS). Secondary endpoints included local control, progression-free survival (PFS), and adverse event occurrence. Carbon-ion radiotherapy with a dose of 57.6-64.0 Gy (relative biological effectiveness) in 16 fractions was delivered concurrently with DAV therapy, and 2 cycles of adjuvant DAV therapy were administered every 6 weeks. The median follow-up periods were 15.5 months for all patients, and 31.2 months for 12 surviving patients. All patients had locally advanced T4a or T4b disease in the rhino-sinus area. In 16 patients (76.2%), 3 cycles of planned DAV therapy were completed. The 3-year OS and PFS rates were 49.2% and 37.0% respectively. The 3-year local control rate was 92.3%. Eleven patients (52%) developed distant metastasis, which was the most frequent pattern of the first failure. Commonly presenting acute grade 2-3 toxicities associated with radiotherapy and chemotherapy were mucositis (11 patients [53%]) and leukopenia (9 patients [43%]), which improved with conservative therapy. None of the patients developed grade 3 or greater late toxicities. Carbon-ion radiotherapy in combination with DAV therapy led to excellent local control for advanced mucosal melanoma within acceptable toxicities. The efficacy of additional DAV therapy in improving survival was weaker than expected as distant metastases still occurred frequently. Trial registration no. UMIN000007939.

Prospective observational study of carbon-ion radiotherapy for non-squamous cell carcinoma of the head and neck.

To evaluate the efficacy and safety of carbon-ion radiotherapy for non-squamous cell carcinoma of the head and neck, 35 patients were enrolled in this prospective study. The primary end-point was the 3-year local control rate, and the secondary end-points included the 3-year overall survival rate and adverse events. Acute and late adverse events were evaluated according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up time for all patients was 39 months. Thirty-two and three patients received 64.0 Gy (relative biological effectiveness) and 57.6 Gy (relative biological effectiveness) in 16 fractions, respectively. Adenoid cystic carcinoma was dominant (60%). Four patients had local recurrence and five patients died. The 3-year local control and overall survival rates were 93% and 88%, respectively. Acute grade 2-3 radiation mucositis (65%) and dermatitis (31%) was common, which improved immediately with conservative therapy. Late mucositis of grade 2, grade 3, and grade 4 were observed in 11, one, and no patients, respectively. There were no adverse events of grade 5. Carbon-ion radiotherapy achieved excellent local control and overall survival rates for non-squamous cell carcinoma. However, the late mucosal adverse events were not rare, and meticulous treatment planning is required. Trial registration no. UMIN000007886.

Concurrent chemoradiotherapy with conventional fractionated radiotherapy and low-dose daily cisplatin plus weekly docetaxel for T2N0 glottic cancer.

BACKGROUND: To assess the efficacy of concurrent chemoradiotherapy (CCRT) with daily low-dose cisplatin (CDDP) plus weekly docetaxel (DTX) for patients with T2N0 glottic cancer. METHODS: Between January 2004 and December 2013, 62 treatment-naive patients with histologically proven T2N0 glottic cancer were treated with concurrent chemoradiotherapy. Radiation therapy (RT; 2 Gy daily fractions up to a total dose of 66 Gy) was administered in combination with daily low-dose CDDP (6 mg/m2, five times a week), plus weekly DTX (10 mg/m2) for up to 4 weeks from the commencement of RT. RESULTS: Median duration of follow-up was 70 months. The actuarial 3-year and 5-year overall survival rates were 95% and 93%. The 3-year and 5-year cause-specific survival rates were both 100%. The actuarial 3-year and 5-year local control rates were 94% and 94%, respectively. Hematologic toxicity (neutoropenia of severity ≥ Grade 3) was observed in 8% of the patients, and non-hematologic toxicity (radiation mucositis of severity ≥ Grade 3) developed in one patient (2%). Radiation dermatitis of severity ≥ Grade 3 and laryngeal necrosis developed in one patient. CONCLUSION: CCRT with weekly DTX and low-dose CDDP appears to be a practical and safe modality and is expected to improve local control. TRIAL REGISTRATION: UMIN000025046 . Registered 1 October 2015, retrospectively registered.

Clinical Outcomes of Definitive and Postoperative Radiotherapy for Stage I-IVB Hypopharyngeal Cancer.

BACKGROUND: Hypopharyngeal cancer is relatively rare disease and continues to have a poor prognosis. This study analyzed the efficacy and safety of radiotherapy for stage I-IVB hypopharyngeal cancer. PATIENTS AND METHODS: Between 2000 and 2015, 72 patients were treated with definitive radiotherapy and 29 patients with stage IVA were treated with postoperative radiotherapy. RESULTS: With definitive radiotherapy, the 3-year locoregional control rates for stage I-II, III, IVA, and IVB disease were 89%, 74%, 51% and 0%, respectively. The 3-year overall survival rates for patients with stage I-II, III, IVA and IVB disease were 84%, 89%, 55% and 15%, respectively. In patients with stage IVA disease treated with postoperative radiotherapy, 3-year locoregional control and overall survival rates were 83% and 75%, respectively, which were significantly better than those treated with definitive radiotherapy. CONCLUSION: Definitive radiotherapy was effective for stage I-III disease. Surgery and postoperative radiotherapy improved the survival rate of patients with stage IVA hypopharyngeal cancer.

[Sequential Chemoradiotherapy for Advanced Head and Neck Cancer: A Clinical Study with 33 Cases].

A total of 33 patients with advanced head and neck cancer (AHNC) treated with sequential chemoradiotherapy (SCRT) were retrospectively evaluated at Gunma University Hospital between 2009 and 2011. The regimen of SCRT was docetaxel, cisplatin, and fluorouracil (TPF)-based induction chemotherapy (ICT), accompanied by docetaxel and cisplatin-based concurrent chemoradiotherapy (CCRT), and oral administration of TS-1 after that. The response rate was 61%, the 3-year overall survival rate was 42%, the non-tumor-bearing survival rate was 27%, and the tumor-bearing survival rate was 15%. Fourteen of 33 patients were tumor-free, and their 3-year overall survival rate was surprisingly 86%. On the other hand, 3-year overall survival rate in the remaining 19 patients was significantly low. To select good response cases for ICT was important. In such cases, TPF should be applied repeatedly, which achieved a 61% response rate even in AHNC. A long-term TS-1 oral medication suppressed cancer regrowth and contributed to long-term survival.

Expression of ER stress markers (GRP78/BiP and PERK) in adenoid cystic carcinoma.

CONCLUSION: A high GRP78/BiP expression was proved to be a significant marker for predicting poor outcome after surgery. GRP78/BiP may be a promising molecular target for treatment of ACC. BACKGROUND: The glucose-regulated protein GRP78/BiP plays a crucial role in the endoplasmic reticulum (ER) stress. The level of GRP78 is highly elevated in various human cancers, but the clinicopathological significance of GRP78/BiP remains controversial in patients with adenoid cystic carcinoma (ACC). METHODS: A total of 26 ACC patients were analyzed, and tumor specimens were stained by immunohistochemistry for GRP78/BiP, PERK, Ki-67, and microvessel density (MVD) determined by CD34. RESULTS: GRP78/BiP and PERK were highly expressed in 58% (15/26) and 35% (9/26), respectively. The high expression of GRP78/BiP was significantly associated with PERK, cell proliferation and angiogenesis.

A Case of Maxillary Arteriovenous Fistula Rupture Treated by Vascular Interventional Radiology.

A 64-year-old woman with neurofibromatosis type 1 was admitted because of a sudden hematoma in her right neck and throat. To prevent an airway obstruction, tracheostomy was performed, but bleeding into the trachea persisted and was difficult to stop. Bleeding arose from a vessel lesion in the right parapharyngeal space, passed through the paratracheal space, and finally reached the tracheostomy wound. An arteriovenous fistula (AVF) in the maxillary artery was revealed by angiography. We diagnosed rupture of the varix resulting from venous high pressure caused by the AVF. The patient was treated by vascular interventional radiology (IVR). A large number of platinum coils were inserted and N-butyl-2-cyanoacrylate (NBCA) was embolized in the AVF and varix. Although innovative vascular IVR was better than surgery to treat AVF of the head and neck lesion, some problems were encountered. The cost for the provided medical services was high, and NBCA was not approved by the pharmaceutical affairs law in Japan.

[Prediction of Post-operative Lymph Node Metastasis with a Molecular Biological Test in Head and Neck Cancer].

We assessed herein the post-operative lymph node metastasis in head and neck cancer, using the One-step nucleotide amplification (OSNA) method targeting matrix metalloproteinase 7 (MMP-7). Compared with the pathological test, the molecular biological test revealed more lymph node metastasis, resulting in poor prognosis. Six cases, of which the number of lymph node metastasis was the same between pathological and molecular biological test, survived. On the other hand, three of four cases, in which number of lymph node metastasis in the molecular biological test were larger than the pathological test, died from metastasis. We concluded that the pathological test underestimated metastasis, and OSNA with MMP-7 was useful for the prediction of post-operative lymph node metastasis.

Multi-slice computed tomography-assisted endoscopic transsphenoidal surgery for pituitary macroadenoma: a comparison with conventional microscopic transsphenoidal surgery.

OBJECTIVES: Intraoperative computed tomography (iCT) is a reliable method for the detection of residual tumour, but previous single-slice low-resolution computed tomography (CT) without coronal or sagittal reconstructions was not of adequate quality for clinical use. The present study evaluated the results of multi-slice iCT-assisted endoscopic transsphenoidal surgery for pituitary macroadenoma. METHODS: This retrospective study included 30 consecutive patients with newly diagnosed or recurrent pituitary macroadenoma with supradiaphragmatic extension who underwent endoscopic transsphenoidal surgery using iCT (eTSS+iCT group), and control 30 consecutive patients who underwent conventional endoscope-assisted transsphenoidal surgery (cTSS group). The tumour volume was calculated by multiplying the tumour area by the slice thickness. Visual acuity and visual field were estimated by the visual impairment score (VIS). RESULTS: The resection extent, (preoperative tumour volume - postoperative residual tumour volume)/preoperative tumour volume, was 98.9% (median) in the eTSS+iCT group and 91.7% in the cTSS group, and had significant difference between the groups (P = 0.04). Greater than 95 and >90% removal rates were significantly higher in the eTSS+iCT group than in the cTSS group (P = 0.02 and P = 0.001, respectively). However, improvement in VIS showed no significant difference between the groups. The rate of complications also showed no significant difference. DISCUSSION: Multi-slice iCT-assisted endoscopic transsphenoidal surgery may improve the resection extent of pituitary macroadenoma. Multi-slice iCT may have advantages over intraoperative magnetic resonance imaging in less expensive, short acquisition time, and that special protection against magnetic fields is not needed.

Expression of Amino Acid Transporters (LAT1 and ASCT2) in Patients with Stage III/IV Laryngeal Squamous Cell Carcinoma.

The aim of this study is to evaluate the clinicopathological significance of L-type amino acid transporter 1 (LAT1) expression in patients with advanced laryngeal squamous cell carcinoma (LSCC). A total of 73 patients with advanced LSCC were retrospectively reviewed. Tumor sections were stained by immunohistochemistry for LAT1, 4F2hc, system ASC amino acid transporter-2 (ASCT2), cell proliferation by Ki-67, microvessel density (MVD) determined by CD34 and p53. A positive LAT1, 4F2hc and ASCT2 expression (staining more than a quarter) in the primary sites were recognized in 85, 80 and 45 %, respectively, and a high LAT1, 4F2hc and ASCT2 expression (staining more than a half) yielded 48, 31 and 18 %, respectively. High expression of LAT1 was significantly associated with lymph node metastasis, 4F2hc, ASCT2, Ki-67 and p53. The expression of LAT1 was significantly correlated with ASCT2, 4F2hc, cell proliferation, and MVD. By univariate analysis, there was no statistically significant relationship between LAT1 expression and prognosis in advanced LSCC. LAT1, 4F2hc and ASCT2 were highly expressed in patients with advanced laryngeal cancer. Our study suggests that the expression of LAT1 plays a crucial role in the metastasis and tumor progression in advanced LSCC.

Oncogenic osteomalacia caused by an occult paranasal sinus tumor.

Oncogenic osteomalacia (OOM) is a rare bone disease characterized by inadequate bone mineralization and is caused by a humoral factor mainly produced by benign mesenchymal tumors. We report a case of OOM caused by an occult phosphaturic mesenchymal tumor in the paranasal sinus. The causative tumor was small and localized in the ethmoid sinus, and the patient did not exhibit any nasal symptoms. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) depicted the location of the occult tumor, and systemic venous sampling followed by assessments of the samples' fibroblast growth factor 23 (FGF23) concentrations confirmed that the tumor secreted FGF23. The tumor was resected via an external surgical approach, resulting in the complete relief of the patient's symptoms. The combination of FDG-PET and systemic venous sampling to assess serum FGF23 levels is useful for identifying small asymptomatic OOM-associated tumors. Such tumors are rare, but a significant proportion of them develop in the head and neck region, and complete resection is the most effective treatment. It is important that ENT surgeons are aware of the characteristics of OOM.

CD98 as a novel prognostic indicator for patients with stage III/IV hypopharyngeal squamous cell carcinoma.

BACKGROUND: Both L-type amino acid transporter 1 (LAT1) and CD98 are strongly expressed in primary human cancer and play essential roles in tumor growth. We studied the clinicopathological significance of LAT1 and CD98 expression in hypopharyngeal squamous cell carcinoma (SCC). METHODS: A total of 70 patients with stage III/IV disease were retrospectively reviewed. Immunohistochemical staining of tumor sections was used to examine LAT1, CD98, Ki-67, CD34, and p53. RESULTS: High LAT1 and CD98 expression were noted in 60.0% and 47.1%, respectively (p = .174). A statistically significant correlation was recognized between LAT1 and CD98 expression and both expressions were closely associated with tumor cell proliferation. Although LAT1 expression was not significantly associated with poor survival, multivariate analysis revealed high CD98 expression to be an independent prognostic factor for predicting a poor outcome. CONCLUSION: CD98 is a promising prognostic marker for predicting outcomes after surgical treatment in patients with advanced hypopharyngeal SCC.

Combined small cell carcinoma of the sinonasal tract associated with syndrome of inappropriate secretion of antidiuretic hormone: A case report.

Combined small cell carcinoma (SmCC) and squamous cell carcinoma (SqCC) is a rare malignant neoplasm in the head and neck. This study presents the first reported case of combined SmCC and SqCC originating from the sinonasal tract accompanied by syndrome of inappropriate secretion of antidiuretic hormone (SIADH). An 80-year-old female presented with a four-week history of right nasal discharge, nasal obstruction and left neck swelling. Imaging studies revealed a tumorous lesion in the maxillary sinus encroaching upon the right nasal cavity and left cervical lymph node (LN) swelling. An incisional biopsy carried out from the right maxillary sinus and LNs resulted in a diagnosis of combined SmCC with SqCC, staged as T4aN2cM0. Clinical examination revealed a sustained increase of antidiuretic hormone, hyponatremia with urinary sodium increase, and serum hypo-osmosis, resulting in SIADH. Water restriction to <1,000 ml/day was effective in improving sodium and osmotic imbalance. Curative treatment for the tumor was not prescribed due to the poor condition of the patient. Palliative treatment was administered and the patient succumbed to cachexia five months after histological diagnosis. The presence of SIADH may have marked implications for the treatment and prognosis of this disease.

Alteration of cancer stem cell-like phenotype by histone deacetylase inhibitors in squamous cell carcinoma of the head and neck.

Recent progression in the understanding of stem cell biology has greatly facilitated the identification and characterization of cancer stem cells (CSCs). Moreover, evidence has accumulated indicating that conventional cancer treatments are potentially ineffective against CSCs. Histone deacetylase inhibitors (HDACi) have multiple biologic effects consequent to alterations in the patterns of acetylation of histones and are a promising new group of anticancer agents. In this study, we investigated the effects of two HDACi, suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA), on two CD44+ cancer stem-like cell lines from squamous cell carcinoma of the head and neck (SCCHN) cultured in serum-free medium containing epidermal growth factor and basic fibroblast growth factor. Histone deacetylase inhibitors inhibited the growth of SCCHN cell lines in a dose-dependent manner as measured by MTS assays. Moreover, HDACi induced cell cycle arrest and apoptosis in these SCCHN cell lines. Interestingly, the expression of cancer stem cell markers, CD44 and ABCG2, on SCCHN cell lines was decreased by HDACi treatment. In addition, HDACi decreased mRNA expression levels of stemness-related genes and suppressed the epithelial-mesencymal transition phenotype of CSCs. As expected, the combination of HDACi and chemotherapeutic agents, including cisplatin and docetaxel, had a synergistic effect on SCCHN cell lines. Taken together, our data indicate that HDACi not only inhibit the growth of SCCHN cell lines by inducing apoptosis and cell cycle arrest, but also alter the cancer stem cell phenotype in SCCHN, raising the possibility that HDACi may have therapeutic potential for cancer stem cells of SCCHN.

Development of a new method using narrow band imaging for taste assessment.

OBJECTIVES/HYPOTHESIS: The observation of fungiform papillae is a useful objective taste examination. The purpose of this study is to develop a new method using narrow band imaging for assessment of taste function. STUDY DESIGN: Using a narrow band imaging endoscope, we assessed the number and blood vessel morphology of fungiform papillae and compared with the gustatory threshold by the filter paper disc test. METHODS: The number of fungiform papillae was counted in 20 mm(2) , and blood vessels in fungiform papillae were evaluated morphologically by a five-point scoring system in 11 patients who had undergone middle ear surgery. The filter taste disc test was performed simultaneously to obtain the gustatory threshold and was compared with the number and blood vessel morphology of fungiform papillae. RESULTS: Using a narrow band imaging endoscope, we could clearly detect not only fungiform papillae but also blood vessel morphology. There was a significant correlation between the values of the number of papillae and blood vessel morphology. Moreover, these two parameters revealed a significant inverse correlation with gustatory function. As expected, both parameters on the affected side were significant lower than those on the unaffected side in patients. CONCLUSIONS: The assessment of fungiform papillae using narrow band imaging endoscopy is easy, highly sensitive, and reliable; therefore, it might be useful as an objective examination of taste function. LEVEL OF EVIDENCE: N/A.

Clinicopathological significance of L-type amino acid transporter 1 (LAT1) expression in patients with adenoid cystic carcinoma.

The expression of L-type amino acid transporter 1 (LAT1) is correlated with tumor cell growth and survival. However, the clinicopathological significance of LAT1 expression in adenoid cystic carcinoma (ACC) remains to be elucidated. The aim of this study is to investigate the clinicopathological significance of LAT1 expression in ACC. A total of 30 patients with ACC were retrospectively reviewed. Tumor sections were stained by immunohistochemistry for LAT1, p53, and CD98, and cell proliferation and microvessel density (MVD) were determined by Ki-67 and CD34, respectively. High LAT1 and CD98 expression were observed in 27 % (8/30) and 23 % (7/30) of samples, respectively (p > 0.999). The high expression of LAT1 was significantly correlated with cell proliferation (Ki-67) and the cell cycle regulator p53. By univariate analysis, solid histological pattern, maxillary tumor site, LAT1, CD98, Ki-67 and p53 were significantly associated with poor prognosis. Multivariate analysis demonstrated that the high expression of LAT1 was an independent prognostic factor for predicting poor prognosis after surgical resection. LAT1 is a promising clinical marker to predict the outcome after surgery in patients with ACC.

Improvement of tracheal flap method for laryngotracheal separation.

OBJECTIVES/HYPOTHESIS: Recurrent pneumonia due to intractable aspiration is a life-threatening disease. A tracheal flap method for children without previous tracheostomy has been previously reported. This study reports that improvements of this method and its three subtypes are widely applicable to patients with various conditions. STUDY DESIGN: Surgical technique study. METHODS: The tracheal flap method does not involve transection of the trachea but achieves laryngotracheal separation using the tracheal, mucoperichondrial, and sternohyoid muscle, along with anterior cervical skin flaps. This method can be divided into three subtypes as follows: A-type, utilizing the tracheal flap (for patients without previous tracheostomy); B-type, utilizing the mucoperichondrial and sternohyoid muscle flaps (for patients lacking an anterior tracheal wall); and C-type, utilizing the esophageal flap (for patients with severe hypersalivation). In all three subtypes, the anterior cervical skin flap is employed. RESULTS: The tracheal flap method was performed in 30 patients (24 children and six adults) at risk of developing intractable aspiration pneumonia. In all 30 cases, aspiration pneumonia was prevented without severe complications. No fistula formation was observed. CONCLUSIONS: All three subtypes (A-, B-, and C-type) of the tracheal flap method are effective in preventing the recurrence of aspiration pneumonia. This method is applicable to diverse patient backgrounds regardless of age or previous tracheostomy. It is less invasive than Lindeman procedure. Furthermore, this method is acceptable to patients' families and improves the QOL of both patients and caregivers.

Intraoperative molecular assessment for lymph node metastasis in head and neck squamous cell carcinoma using one-step nucleic acid amplification (OSNA) assay.

BACKGROUND: Conventional intraoperative pathological examination for Sentinel node navigation surgery (SNNS) has been controversial. We evaluated the efficacy of one-step nucleic acid amplification (OSNA) assay for intraoperative diagnosis of cervical lymph node (CLN) metastasis compared with histopathological examination in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: A total of 175 CLNs dissected from 56 patients with HNSCC who underwent surgery at Aichi Cancer Center, Kyorin University, Gunma University or Fukushima Medical University, between April 2008 and December 2011 were enrolled. CLN samples were sectioned into four equal pieces, with two of each used for OSNA assay and other histopathological examinations. The diagnostic value of OSNA assay in HNSCC patients in predicting the results of histopathological diagnosis was evaluated using the area under the receiver operating characteristic (AUROC) curve. RESULTS: OSNA assay showed acceptable efficacy in the detection of pathological CLN metastasis (AUROC 0.918, 95 % confidence interval [CI] 0.852-0.984). Regarding the CK19mRNA cutoff value, the optimum cutoff point in HNSCC patients was 131 copies/µl (sensitivity: 82.4, 95 % CI 65.5-93.2; specificity: 99.3, 95 % CI 96.1-100.0; positive likelihood ratio 116.1; negative likelihood ratio 0.2]. CONCLUSIONS: We demonstrated that OSNA assay is useful in intraoperative diagnosis for CLN metastasis in patients with HNSCC. OSNA assay could be applied for SNNS in HNSCC patients.