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Featured researches published by Toshimichi Yasui.


PLOS ONE | 2014

Human papillomavirus and cystic node metastasis in oropharyngeal cancer and cancer of unknown primary origin.

Toshimichi Yasui; Eiichi Morii; Yoshifumi Yamamoto; Tadashi Yoshii; Yukinori Takenaka; Susumu Nakahara; Takeshi Todo; Hidenori Inohara

The clinical significance of human papillomavirus (HPV) in neck node metastasis from cancer of unknown primary (CUP) is not well established. We aimed to address the relationship of HPV status between node metastasis and the primary tumor, and also the relevance of HPV status regarding radiographically detected cystic node metastasis in head and neck squamous cell carcinoma (HNSCC) and CUP. HPV DNA was examined in 68 matched pairs of node metastasis and primary tumor, and in node metastasis from 27 CUPs. In surgically treated CUPs, p16 was examined immunohistochemically. When tonsillectomy proved occult tonsillar cancer in CUP, HPV DNA and p16 were also examined in the occult primary. Cystic node metastasis on contrast-enhanced computed tomography scans was correlated with the primary site and HPV status in another series of 255 HNSCCs and CUPs with known HPV status. Node metastasis was HPV-positive in 19/37 (51%) oropharyngeal SCCs (OPSCCs) and 10/27 (37%) CUPs, but not in non-OPSCCs. Fluid was collected from cystic node metastasis using fine needle aspiration in two OPSCCs and one CUP, and all fluid collections were HPV-positive. HPV status, including the presence of HPV DNA, genotype, and physical status, as well as the expression pattern of p16 were consistent between node metastasis and primary or occult primary tumor. Occult tonsillar cancer was found more frequently in p16-positive CUP than in p16-negative CUP (odds ratio (OR), 39.0; 95% confidence interval (CI), 1.4–377.8; P = 0.02). Radiographically, cystic node metastasis was specific to OPSCC and CUP, and was associated with HPV positivity relative to necrotic or solid node metastasis (OR, 6.2; 95% CI, 1.2–45.7; P = 0.03). In conclusion, HPV status remains unchanged after metastasis. The occult primary of HPV-positive CUP is most probably localized in the oropharynx. HPV status determined from fine needle aspirates facilitates the diagnosis of cystic node metastasis.


Cancer Science | 2014

Human papillomavirus and p53 mutations in head and neck squamous cell carcinoma among Japanese population

Hiromi Maruyama; Toshimichi Yasui; Tomoko Ishikawa-Fujiwara; Eiichi Morii; Yoshifumi Yamamoto; Tadashi Yoshii; Yukinori Takenaka; Susumu Nakahara; Takeshi Todo; Tadashi Hongyo; Hidenori Inohara

We aimed to reveal the prevalence and pattern of human papillomavirus (HPV) infection and p53 mutations among Japanese head and neck squamous cell carcinoma (HNSCC) patients in relation to clinicopathological parameters. Human papillomavirus DNA and p53 mutations were examined in 493 HNSCCs and its subset of 283 HNSCCs. Oropharyngeal carcinoma was more frequently HPV‐positive than non‐oropharyngeal carcinoma (34.4% vs 3.6%, P < 0.001), and HPV16 accounted for 91.1% of HPV‐positive tumors. In oropharyngeal carcinoma, which showed an increasing trend of HPV prevalence over time (P < 0.001), HPV infection was inversely correlated with tobacco smoking, alcohol drinking, p53 mutations, and a disruptive mutation (P = 0.003, <0.001, <0.001, and <0.001, respectively). The prevalence of p53 mutations differed significantly between virus‐unrelated HNSCC and virus‐related HNSCC consisting of nasopharyngeal and HPV‐positive oropharyngeal carcinomas (48.3% vs 7.1%, P < 0.001). Although p53 mutations were associated with tobacco smoking and alcohol drinking, this association disappeared in virus‐unrelated HNSCC. A disruptive mutation was never found in virus‐related HNSCC, whereas it was independently associated with primary site, such as the oropharynx and hypopharynx (P = 0.01 and 0.03, respectively), in virus‐unrelated HNSCC. Moreover, in virus‐unrelated HNSCC, G:C to T:A transversions were more frequent in ever‐smokers than in never‐smokers (P = 0.04), whereas G:C to A:T transitions at CpG sites were less frequent in ever‐smokers than in never‐smokers (P = 0.04). In conclusion, HNSCC is etiologically classified into virus‐related and virus‐unrelated subgroups. In virus‐related HNSCC, p53 mutations are uncommon with the absence of a disruptive mutation, whereas in virus‐unrelated HNSCC, p53 mutations are common, and disruptive mutagenesis of p53 is related with oropharyngeal and hypopharyngeal carcinoma.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2015

Chemoradiation therapy for squamous cell carcinoma of the external auditory canal: A meta‐analysis

Yukinori Takenaka; Hironori Cho; Susumu Nakahara; Yoshifumi Yamamoto; Toshimichi Yasui; Hidenori Inohara

The standard treatment for advanced external auditory canal squamous cell carcinoma (SCC) is subtotal temporal bone resection and postoperative radiation therapy (RT), whereas chemoradiation therapy (CRT) is used in some institutions to improve patient prognosis. The purpose of this study was to evaluate the efficacy of CRT in external auditory canal SCC treatment.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2015

Prognostic significance of body mass index before treatment for head and neck cancer.

Yukinori Takenaka; Norihiko Takemoto; Susumu Nakahara; Yoshifumi Yamamoto; Toshimichi Yasui; Atshushi Hanamoto; Takahito Fukusumi; Takahiro Michiba; Hironori Cho; Masashi Yamamoto; Hidenori Inohara

Patients with head and neck cancer frequently experience malnutrition. The purpose of this study was to examine the impact of nutritional status on prognosis and its association with treatment modalities.


Cancer Medicine | 2014

Volumetric PET/CT parameters predict local response of head and neck squamous cell carcinoma to chemoradiotherapy

Atsushi Hanamoto; Mitsuaki Tatsumi; Yukinori Takenaka; Toshimitsu Hamasaki; Toshimichi Yasui; Susumu Nakahara; Yoshifumi Yamamoto; Yuji Seo; Fumiaki Isohashi; Kazuhiko Ogawa; Jun Hatazawa; Hidenori Inohara

It is not well established whether pretreatment 18F‐FDG PET/CT can predict local response of head and neck squamous cell carcinoma (HNSCC) to chemoradiotherapy (CRT). We examined 118 patients: 11 with nasopharyngeal cancer (NPC), 30 with oropharyngeal cancer (OPC), and 77 with laryngohypopharyngeal cancer (LHC) who had completed CRT. PET/CT parameters of primary tumor, including metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum and mean standardized uptake value (SUVmax and SUVmean), were correlated with local response, according to primary site and human papillomavirus (HPV) status. Receiver‐operating characteristic analyses were made to access predictive values of the PET/CT parameters, while logistic regression analyses were used to identify independent predictors. Area under the curve (AUC) of the PET/CT parameters ranged from 0.53 to 0.63 in NPC and from 0.50 to 0.54 in OPC. HPV‐negative OPC showed AUC ranging from 0.51 to 0.58, while all of HPV‐positive OPCs showed complete response. In contrast, AUC ranged from 0.71 to 0.90 in LHC. Moreover, AUCs of MTV and TLG were significantly higher than those of SUVmax and SUVmean (P < 0.01). After multivariate analysis, high MTV >25.0 mL and high TLG >144.8 g remained as independent, significant predictors of incomplete response compared with low MTV (odds ratio [OR], 13.4; 95% confidence interval [CI], 2.5–72.9; P = 0.003) and low TLG (OR, 12.8; 95% CI, 2.4–67.9; P = 0.003), respectively. In conclusion, predictive efficacy of pretreatment 18F‐FDG PET/CT varies with different primary sites and chosen parameters. Local response of LHC is highly predictable by volume‐based PET/CT parameters.


Acta Oto-laryngologica | 2015

Prognostic significance of serum squamous cell carcinoma antigen in patients with head and neck cancer

Ryusuke Imai; Yukinori Takenaka; Toshimichi Yasui; Susumu Nakahara; Yoshifumi Yamamoto; Atsushi Hanamoto; Norihiko Takemoto; Takahito Fukusumi; Hironori Cho; Masashi Yamamoto; Hidenori Inohara

Abstract Conclusions: Serum squamous cell carcinoma antigen (SCC-Ag) level was an independent prognostic factor for survival in patients with head and neck squamous cell carcinoma (HNSCC), and the prognostic value depended on the carcinoma site. Objectives: To assess the value of SCC-Ag as a prognostic indicator in patients with HNSCC and to determine the effect of primary tumor site on prognosis. Methods: We reviewed 493 patients with HNSCC between 2004 and 2012. The chi-squared test was used to assess associations between SCC-Ag levels and TNM classification. A Cox proportional hazard model was used to assess the hazard ratio of SCC-Ag at different sites for death, and it was analyzed as a continuous variable. Results: The median serum level of SCC-Ag was 1.1 ng/ml (range 0–20). SCC-Ag was significantly higher in patients with advanced T and N classification tumors. Primary sites in the oral cavity, in the hypopharynx, advanced T and N classification, distant metastasis, and SCC-Ag were negatively associated with survival in univariate analysis. Multivariate analysis revealed that SCC-Ag was a significant risk factor for overall survival in cancers of the oral cavity, hypopharynx, and larynx, but not in oropharyngeal cancer.


Auris Nasus Larynx | 2014

Synchronous bilateral tonsillar carcinomas associated with human papillomavirus.

Susumu Nakahara; Toshimichi Yasui; Yukinori Takenaka; Yoshifumi Yamamoto; Tadashi Yoshii; Eiichi Morii; Hidenori Inohara

Although the incidence of human papillomavirus (HPV)-positive oropharyngeal carcinoma is increasing, only a limited number of synchronous bilateral HPV-positive tonsillar carcinomas have been reported to date. Here, we describe an additional case of 61-year-old female. Pathological analysis proved squamous cell carcinoma in biopsy specimens from bilateral tonsillar lesions and a fine needle aspirate from an enlarged cervical node. Polymerase chain reaction (PCR) and direct sequencing showed HPV-16 DNA in all of the biopsy specimens and fine needle aspirate with completely concordant sequences. Bilateral tonsillar lesions were immunohistochemically positive for p16. Taken together with radiological findings, she was diagnosed to have bilateral tonsillar carcinomas (cT1N2bM0 on the right side and cT2N0M0 on the left side). We administered concurrent chemoradiotherapy to treat these synchronous lesions, and the restaging workup resulted in overall complete response. No recurrent and/or metastatic disease has been evident 20 months after the restaging. It seems reasonable to include bilateral tonsils as a therapeutic target in the treatment of HPV-positive unknown primary carcinoma.


Acta Oto-laryngologica | 2014

Factors associated with malnutrition in patients with head and neck cancer

Yukinori Takenaka; Masashi Yamamoto; Susumu Nakahara; Yoshifumi Yamamoto; Toshimichi Yasui; Atshushi Hanamoto; Norihiko Takemoto; Takahito Fukusumi; Takahiro Michiba; Hironori Cho; Hidenori Inohara

Abstract Conclusions: Comorbidities as well as T classification were the primary determinants for the nutritional status of patients with head and neck cancer. Objectives: We aimed to elucidate the underlying conditions of malnutrition in patients with head and neck cancer. Methods: We retrospectively reviewed 726 patients diagnosed with head and neck cancer between 2004 and 2013. Associations between malnutrition and clinical parameters were assessed using univariate and multivariate analyses. Results: Median body mass index was 21.5 (range 11.6–38.0). According to World Health Organization criteria, the nutritional status of these patients was classified into four groups: underweight (18%), normal (63%), overweight (17%), and obese (1%). Comorbidities were detected in 40% of patients. Multivariate analysis revealed the following factors to be independent factors associated with malnutrition: advanced T stage, metachronous cancer, collagen disease, gastrointestinal disease, and pulmonary disease.


Auris Nasus Larynx | 2015

Docetaxel, cisplatin, and fluorouracil for patients with inoperable recurrent or metastatic head and neck squamous cell carcinoma

Hironori Cho; Suetaka Nishiike; Yoshifumi Yamamoto; Yukinori Takenaka; Susumu Nakahara; Toshimichi Yasui; Atsushi Hanamoto; Hidenori Inohara

OBJECTIVE The first-line treatment for inoperable recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) has long been the combination of cisplatin and fluorouracil (PF). Recently, cetuximab has been shown to provide an additional survival benefit to PF. It remains unknown whether docetaxel adds additional benefits to PF. Therefore, we sought to evaluate the efficacy and toxicity of docetaxel, cisplatin, and fluorouracil (TPF) for inoperable recurrent or metastatic HNSCC. METHODS A retrospective chart review from January 2005 to March 2013 identified patients who were treated with docetaxel 60 mg/m(2) on day 1, followed by cisplatin 60 mg/m(2) on day 1, and fluorouracil 600 mg/m(2)/day on days 1-5 (modified TPF) every 4 weeks for inoperable recurrent or metastatic HNSCC. RESULTS Twenty-four patients were identified; seven and five patients had locoregional disease only and distant metastasis only, respectively, while 12 patients had locoregional disease and distant metastasis simultaneously. Of the 17 patients with distant metastasis, multiple organs were affected in 9 patients, with the most frequently affected organ being the lung (n=11). Three patients had no prior treatment, whereas 21 patients underwent intensive prior treatment. In 17 of 21 patients who had received prior treatment, the treatment included chemoradiotherapy and/or chemotherapy. The median number of cycles of modified TPF was two (range, 1-5). One patient showed complete response, four patients showed partial response, two patients had stable disease, and 17 patients had progressive disease. Overall, the rate of objective response was 21%, with a 95% confidence interval (CI) of 9-40%. Median overall survival was 8.0 months (95%CI, 4.4-10.6 months). The treatment efficacy differed significantly according to extent of disease. Objective response in patients with distant metastasis alone was better than in patients with locoregional disease with or without distant metastasis (60% vs. 11%, respectively; P=0.02). Median overall survival in the former patients was longer than in the latter patients (not reached vs. 7.0 months, respectively; P=0.02). Fifteen patients (63%) had Grades 3-4 neutropenia, and seven patients (29%) developed Grade 3 febrile neutropenia. There were no toxic deaths. CONCLUSION The efficacy of modified TPF in the setting of first-line treatment for recurrent or metastatic HNSCC is not very high, while the toxicity is acceptable with extensive care. The development of more efficacious chemotherapeutic regimen is required.


PLOS ONE | 2016

Transaminase Activity Predicts Survival in Patients with Head and Neck Cancer.

Yukinori Takenaka; Norihiko Takemoto; Toshimichi Yasui; Yoshifumi Yamamoto; Atsuhiko Uno; Haruka Miyabe; Naoki Ashida; Kotaro Shimizu; Susumu Nakahara; Atshushi Hanamoto; Takahito Fukusumi; Takahiro Michiba; Hironori Cho; Masashi Yamamoto; Hidenori Inohara

Various serum biomarkers have been developed for predicting head and neck squamous cell carcinoma (HNSCC) prognosis. However, none of them have been proven to be clinically significant. A recent study reported that the ratio of aspartate aminotransaminase (AST) to alanine aminotransaminase (ALT) had a prognostic effect on non-metastatic cancers. This study aimed to examine the effect of the AST/ALT ratio on the survival of patients with HNSCC. Clinical data of 356 patients with locoregionally advanced HNSCC were collected. The effect of the AST/ALT ratio on overall survival was analyzed using a Cox proportional hazard model. Moreover, recursive partitioning analysis (RPA) was used to divide the patients into groups on the basis of the clinical stage and AST/ALT ratio. The prognostic ability of this grouping was validated using an independent data set (N = 167). The AST/ALT ratio ranged from 0.42 to 4.30 (median, 1.42) and was a prognostic factor for overall survival that was independent of age, primary sites, and tumor stage (hazard ratio: 1.36, confidence interval: 1.08−1.68, P = 0.010). RPA divided patients with stage IVA into the following two subgroups: high AST/ALT (≥2.3) and low AST/ALT (<2.3) subgroups. The 5-year survival rate for patients with stage III, stage IVA with a low AST/ALT ratio, stage IVA with a high AST/ALT ratio, and stage IVB were 64.8%, 49.2%, 28.6%, and 33.3%, respectively (p < 0.001). Compared with the low AST/ALT group, the adjusted hazard ratio for death was 2.17 for high AST/ALT group (confidence interval: 1.02–.22 P = 0.045). The AST/ALT ratio was demonstrated to be a prognostic factor of HNSCC. The ratio subdivided patients with stage IVA into low- and high-risk groups. Moreover, intensified treatment for the high-risk group may be considered.

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