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Featured researches published by Tomohiro Sakashita.


Archives of Otolaryngology-head & Neck Surgery | 2009

Voice-Related Quality of Life After Treatment of Laryngeal Cancer

Nobuhiko Oridate; Akihiro Homma; Seigo Suzuki; Yuji Nakamaru; Fumiyuki Suzuki; Hiromitsu Hatakeyama; Shigenari Taki; Tomohiro Sakashita; Noriko Nishizawa; Yasushi Furuta; Satoshi Fukuda

OBJECTIVE To determine patient-perceived voice-related quality of life in patients treated with various methods based on the results of Voice-Related Quality of Life (VRQOL) and Voice Handicap Index-10 (VHI-10) questionnaires. DESIGN The VRQOL and VHI-10 questionnaires. SETTING University hospital. PATIENTS One hundred thirty-seven patients who had received definitive treatment of laryngeal cancer were followed-up at Hokkaido University Hospital, Sapporo, Japan, and were alive with no evidence of malignancy at the time of the survey. MAIN OUTCOME MEASURE Patient-perceived voice-related quality of life based on the results of the VRQOL and VHI-10 questionnaires. RESULTS The mean VRQOL scores for patients who had undergone radiotherapy (n = 63), chemoradiotherapy (n = 29), laser surgery (n = 14), or total laryngectomy (n = 27) as final treatment of laryngeal cancer were 92.6, 92.9, 85.5, and 68.4, respectively; the mean VHI-10 scores were 2.87, 2.34, 5.43, and 11.26, respectively. CONCLUSION The VRQOL and VHI-10 questionnaires are important in judging the overall effectiveness of treatment options for laryngeal cancer.


Japanese Journal of Clinical Oncology | 2011

Concomitant Weekly Cisplatin and Radiotherapy for Head and Neck Cancer

Akihiro Homma; Naoya Inamura; Nobuhiko Oridate; Seigo Suzuki; Hiromitsu Hatakeyama; Takatsugu Mizumachi; Satoshi Kano; Tomohiro Sakashita; Rikiya Onimaru; Koichi Yasuda; Hiroki Shirato; Satoshi Fukuda

OBJECTIVE The most common chemoradiotherapy regimen is high-dose (100 mg/m(2)) three-weekly cisplatin with concomitant radiotherapy; however, this protocol is associated with acute and late toxicities. Here, we reviewed the dose intensity and toxicity for concomitant weekly cisplatin and radiotherapy in patients with head and neck cancer. METHODS Fifty-three patients with untreated head and neck cancer were enrolled and evaluated at our institution from April 2006 to April 2010. Weekly cisplatin (40 mg/m(2)) was given on weeks 1, 2, 3, 5, 6 and 7 with radiotherapy, which comprised a standard dose of 70 Gy delivered in 35 daily fractions over 7 weeks. RESULTS Fifty-one patients (96.2%) received the full dose of radiotherapy, while the course was disrupted by adverse events in two. Over the course of the chemotherapy, 31 patients (58.5%) received more than 200 mg/m(2) cisplatin. The toxicity was manageable in all except one patient, who died of sepsis after completing treatment. The 2-year overall survival rate and local progression-free rate for all patients were 93.7% and 88.0%, respectively. The primary site showed a complete response in 52 patients (98.1%) and a partial response in 1 patient (1.9%). The primary disease was well controlled by chemoradiotherapy in 47 patients (88.7%). CONCLUSIONS Weekly cisplatin could be easier to manage than three-weekly cisplatin, because patients can be monitored more regularly for toxicity allowing the schedule to be altered if required. This regimen appears to be a suitable alternative to three-weekly high-dose cisplatin with concomitant radiotherapy.


European Archives of Oto-rhino-laryngology | 2010

Salvage surgery for local recurrence after chemoradiotherapy or radiotherapy in hypopharyngeal cancer patients.

Shigenari Taki; Akihiro Homma; Nobuhiko Oridate; Seigo Suzuki; Fumiyuki Suzuki; Tomohiro Sakashita; Satoshi Fukuda

This retrospective study aimed to assess the role of salvage surgery for local recurrence in hypopharyngeal cancer (HPC) patients who had received radiotherapy (RT) or concomitant chemoradiotherapy (CRT) as an initial treatment. The local recurrence rate, salvage rate after local recurrence and overall survival rate were investigated in 104 HPC patients who received treatment between 1991 and 2005. Local recurrence in the primary site was observed in 41 patients (rate, 39.4%) of whom only 12 could undergo further salvage surgery. Disease control was achieved in seven of these patients (successful salvage rate, 17.1%). The 5-year overall survival rate was 40.6% in the RT/CRT patient group and successful salvage rates for T1, T2, T3 and T4 primary disease were 33.3% (1/3), 20.0% (4/20), 16.7% (2/12) and 0% (0/6), respectively. Severe postoperative complications such as pharyngo-cutaneous fistula were seen in six patients (50.0%). Prognosis of patients with locally recurring HPC after RT/CRT is poor at any primary T-stage and the incidence of postoperative complication is relatively high. This should be taken into consideration when the initial treatment plan is decided and the choice of salvage surgery for such recurrent cases should be carefully determined.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2009

Importance of comorbidity in hypopharyngeal cancer

Akihiro Homma; Tomohiro Sakashita; Nobuhiko Oridate; Fumiyuki Suzuki; Seigo Suzuki; Hiromitsu Hatakeyama; Takatsugu Mizumachi; Shigenari Taki; Satoshi Fukuda

Comorbidity has an impact on survival in laryngeal cancer in several reports. However, the importance of comorbidity in hypopharyngeal cancer (HPC) has not been reported.


British Journal of Cancer | 2013

Superselective intra-arterial cisplatin infusion and concomitant radiotherapy for maxillary sinus cancer

Akihiro Homma; Tomohiro Sakashita; Daisuke Yoshida; Rikiya Onimaru; Kazuhiko Tsuchiya; Fumiyuki Suzuki; Koichi Yasuda; Hiromitsu Hatakeyama; Jun Furusawa; Takatsugu Mizumachi; Satoshi Kano; Naoya Inamura; Shigenari Taki; Hiroki Shirato; Satoshi Fukuda

Background:The purpose of this study was to evaluate the efficacy of superselective cisplatin infusion with concomitant radiotherapy (RADPLAT) for previously untreated patients with the squamous cell carcinoma of maxillary sinus (SCC-MS).Methods:Between 1999 and 2010, 54 patients were given superselective intra-arterial infusions of cisplatin (100–120 mg m−2 per week) with simultaneous intra-venous infusions of thiosulfate to neutralise cisplatin toxicity and conventional radiotherapy (65–70 Gy).Results:One patient (1.9%) was diagnosed with T2, 14 (25.9%) with T3, 27 (50%) with T4a, and 12 (22.2%) with T4b disease. Lymph-node involvement was present in 12 patients (22.2%). During the median follow-up period of 6.4 years, the 5-year local progression-free and overall survival rates were 65.8 and 67.9% for all patients, respectively. No patient died as a result of treatment toxicity or experienced a cerebrovascular accident. Osteonecrosis (n=5), brain necrosis (n=1), and ocular/visual problems (n=14) were observed as late adverse reactions.Conclusion:We have shown excellent overall survival and local progression-free rate in SCC-MS patients treated by RADPLAT with acceptable rates of acute and late toxicity. A multi-institutional trial is needed to prove that this strategy is a feasible and effective approach for the treatment of SCC-MS.


Oral Oncology | 2011

Superselective arterial cisplatin infusion with concomitant radiation therapy for base of tongue cancer

Satoshi Kano; Akihiro Homma; Nobuhiko Oridate; Fumiyuki Suzuki; Hiromitsu Hatakeyama; Takatsugu Mizumachi; Jun Furusawa; Tomohiro Sakashita; Daisuke Yoshida; Rikiya Onimaru; Hiroki Shirato; Satoshi Fukuda

The treatment of base of tongue (BOT) cancer is highly controversial with differing options according to individual institutions, or the primary surgical or radiation therapy bias. We aimed to determine patient outcomes and discuss technical aspects following treatment with concurrent radiation therapy and targeted cisplatin chemotherapy (RADPLAT). We utilized RADPLAT for the definitive treatment of patients with BOT cancers. The 5-year local control and overall survival rate was 92.3% and 90.9% for all patients, respectively, and all surviving patients achieved normal swallowing without a feeding-tube and normal speech without tracheostoma after treatment. Our study found that RADPLAT gave excellent survival rates and organ functions for patients with BOT cancers. We consider that BOT cancer is a good indication for RADPLAT and that the angiographic technique and patient selection are keys to success.


European Radiology | 2017

Prediction of the treatment outcome using intravoxel incoherent motion and diffusional kurtosis imaging in nasal or sinonasal squamous cell carcinoma patients

Noriyuki Fujima; Daisuke Yoshida; Tomohiro Sakashita; Akihiro Homma; Akiko Tsukahara; Yukie Shimizu; Khin Khin Tha; Kohsuke Kudo; Hiroki Shirato

ObjectivesTo evaluate the diagnostic value of intravoxel incoherent motion (IVIM) and diffusional kurtosis imaging (DKI) parameters in nasal or sinonasal squamous cell carcinoma (SCC) patients to determine local control/failure.MethodsTwenty-eight patients were evaluated. MR acquisition used single-shot spin-echo EPI with 12 b-values. Quantitative parameters (mean value, 25th, 50th and 75th percentiles) of IVIM (perfusion fraction f, pseudo-diffusion coefficient D*, and true-diffusion coefficient D), DKI (kurtosis value K, kurtosis corrected diffusion coefficient Dk) and apparent diffusion coefficient (ADC) were calculated. Parameter values at both the pretreatment and early-treatment period, and the percentage change between these two periods were obtained.ResultsMultivariate logistic regression analysis: the percentage changes of D (mean, 25th, 50th, 75th), K (mean, 50th, 75th), Dk (mean, 25th, 50th), and ADC (mean, 25th, 50th) were predictors of local control. ROC curve analysis: the parameter with the highest accuracy = the percentage change of D value with the histogram 25th percentile (0.93 diagnostic accuracy). Multivariate Cox regression analyses: the percentage changes of D (mean, 25th, 50th), K (mean, 50th, 75th), Dk (mean, 25th, 50th) and ADC (mean, 25th, 50th) are predictors.ConclusionsIVIM and DKI parameters, especially the D-value’s histogram 25th percentile, are useful for predicting local control.Key Points• Noninvasive assessment of treatment outcome in SCC patients was achieved using IVIM/DKI.• Several IVIM and DKI parameters can predict the local control.• Especially, the D-value’s histogram 25th percentile has high diagnostic accuracy.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2017

Pretreatment lymphocyte-to-monocyte ratio as an independent prognostic factor for head and neck cancer

Satoshi Kano; Akihiro Homma; Hiromitsu Hatakeyama; Takatsugu Mizumachi; Tomohiro Sakashita; Tomohiko Kakizaki; Satoshi Fukuda

The purpose of this study was to analyze the relationship between pretreatment inflammatory markers and the prognosis of patients with oropharyngeal, hypopharyngeal, and laryngeal cancers.


Journal of Magnetic Resonance Imaging | 2015

Measurement of tumor blood flow in head and neck squamous cell carcinoma by pseudo-continuous arterial spin labeling: Comparison with dynamic contrast-enhanced MRI

Noriyuki Fujima; Kohsuke Kudo; Akiko Tsukahara; Daisuke Yoshida; Tomohiro Sakashita; Akihiro Homma; Khin Khin Tha; Hiroki Shirato

To investigate the feasibility of tumor blood flow (TBF) measurement in head and neck squamous cell carcinoma (HNSCC) using pseudo‐continuous arterial spin labeling (pCASL) in a comparison with dynamic contrast‐enhanced (DCE) perfusion.


Journal of Magnetic Resonance Imaging | 2014

Arterial spin labeling to determine tumor viability in head and neck cancer before and after treatment

Noriyuki Fujima; Kohsuke Kudo; Daisuke Yoshida; Akihiro Homma; Tomohiro Sakashita; Akiko Tsukahara; Khin Khin Tha; Yuri Zaitsu; Satoshi Terae; Hiroki Shirato

To evaluate the feasibility of arterial spin‐labeling (ASL) in head and neck cancer for noninvasive measurement of tumor blood flow (TBF), by comparing 1) the TBF change before and after the treatment, and 2) posttreatment TBF and its reduction rate between residual and nonresidual tumors after treatment.

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