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Dive into the research topics where Katsufumi Hoki is active.

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Featured researches published by Katsufumi Hoki.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1997

Partial laryngectomy in the treatment of radiation-failure of early glottic carcinoma

Ken-ichi Nibu; Shin-etsu Kamata; Kazuyoshi Kawabata; Munenaga Nakamizo; Tomohiko Nigauri; Katsufumi Hoki

This study was undertaken to analyze the functional results, complications, local control rates, and survival in patients undergoing conservation surgery for squamous cell carcinoma (SCC) of the larynx as a salvage procedure for recurrent tumors after previous radiotherapy.


Acta Oto-laryngologica | 1998

Clinical Role of p53 and p21WAF1/CIP1 in Squamous Cell Carcinoma of the Pyriform Sinus

Ken-ichi Nibu; Akio Yanagisawa; Munenaga Nakamizo; Katsufumi Hoki; Tomohiko Nigauri; Kazuyoshi Kawabata; Shin-etsu Kamata

To investigate the clinical significance of p53 and p21WAF1/CIP1 in the advanced squamous cell carcinoma (SCC) of the pyriform sinus, we performed immunohistochemical staining of p53 and p21WAF1/CIP1 on the biopsy specimens from patients with stage III or stage IV SCC of the pyriform sinus. The results were compared with clinico-pathological features, including age, histological grade, TNM classification, number of neck lymph node metastases on histopathological examination (pLN) and prognosis. Specific staining for p53 and p21WAF1/CIP1 was detected in 36% and 32% of the specimens, respectively. Positive staining of p21WAF1/CIP1 was observed not only in the p53-negative specimens but also in the p53-positive specimens. Age (p < 0.05) and pLN (p < 0.001) were regarded as the significant prognostic factors. The 5-year survival rate of the p53-positive patients (55%) was significantly higher than that of the p53-negative patients (26.5%: p < 0.03). However, there is no significant difference between the p53 groups after controlling pLN. Although it was not statistically significant, the 5-year survival rate of the p21WAF1/CIP1-positive patients (58.8%) was higher than that of the p21WAF1/CIP1-negative patients (26.9%). These results suggest that expressions of p53 and p21WAF1/CIP1 are independent genetic alterations that may play different roles in the SCC of the pyriform sinus. Expression of p53 could not be regarded as an independent prognostic factor at this point. Further studies including the molecular biological analysis should be performed in order to determine the clinical role of p21WAF1/CIP1.


Acta Oto-laryngologica | 1985

Control of the Nasal Mucosa by the Tonic Activities of the Autonomic Nervous System in Dogs

Kohji Asakura; Katsufumi Hoki; Akikatsu Kataura; Toshiharu Kasaba; Mamoru Aoki

We studied the effects of stimulation and acute denervation of the cervical sympathetic nerve and the vidian nerve on the nasal vascular tone, as measured by intranasal balloon pressure. Significant vasoconstriction was found during electrical stimulation of the cervical sympathetic nerve. When the cervical sympathetic nerve was sectioned, causing a transient vasoconstriction due to the stimulatory effect of the nerve injury, then significant vasodilation was found in 23 out of 30 experiments. Significant vasodilation during electrical stimulation of the vidian nerve and slight but significant vasoconstriction after sectioning of the vidian nerve were also found. In addition, we found spontaneous nerve discharges in the cervical sympathetic nerve trunks. These nerve discharges increased after stopping the respiratory pump. Differences in these sympathetic nerve discharges between the sides of the body were also recognized.


Acta Oto-laryngologica | 1986

Respiration-related Movements of the Nose in Dogs

Kohji Asakura; Katsufumi Hoki; Akikatsu Kataura; Toshiharu Kasaba; Mamoru Aoki

We studied the respiration-related movements of the canine nose by examining the respiratory oscillations of intranasal balloon pressure and EMG activities of the dilator nares in dogs. Under spontaneous respiration, balloon pressure decreased and EMG activities increased during the early inspiratory phase. These respiratory movements of the nose differed and changed reciprocally in strength between the two sides of the body spontaneously, after painful stimulation or intranasal histamine administration. When the muscle relaxant was administered and the respiration was controlled by the ventilation pump, the intranasal balloon pressure increased during the inspiratory phase. This phenomenon had a completely inverted pattern compared with that during spontaneous respiration. Furthermore, even when the ventilation pump was stopped, respiration-like spontaneous oscillations of the intranasal balloon pressure were recognized. These were abolished by sectioning of the ipsilateral cervical sympathetic nerve trunk. From these findings, the respiration-related movements of the nose were thought to be controlled not only by the cardiac output and the vagal nerve reflexes but also by respiratory activities in the nervous systems controlling the nose, which might be originated from the medullary respiratory centres.


Nippon Jibiinkoka Gakkai Kaiho | 1996

PROGNOSTIC FACTORS OF LATERAL WALL OROPHARYNGEAL SQUAMOUS CELL CARCINOMA

Tomohiko Nigauri; Shin-etsu Kamata; Kazuyoshi Kawabata; Munenaga Nakamizo; Katsufumi Hoki; Hiroki Mitani; Tatsumi Nagahashi; Kazuhiko Yokoshima; Seiichi Yoshimoto

We reviewed 79 patients with squamous cell carcinoma of the lateral wall of the oropharynx who received treatment at the Cancer Institute Hospital. Tokyo, between 1971 and 1990. There were 67 men and 12 women, aged 31 to 81 years (average 59.2 years). The tumors could be staged by TNM classification (UICC 1987) as follows: Stage 10 Stage II 12, Stage III 27, Stage IV 40. It must be noted that more than 50% of the tumors were classified as stage IV. As the initial treatment, 50 patients underwent radical radiotherapy, and the remaining 29 were treated mainly by surgery after pre-operative radiation. Some patients underwent adjuvant chemotherapy, but the role of chemotherapy was not considered in this study. The purpose of the present study was to determine the prognostic factors and to determine the survival rate after each treatment modality. The results were as follows: i) Patients with either T4, over N2b or a stage IV tumor had a significantly poor prognosis. ii) Cox multivariate analysis revealed that age, local extension (base of tongue, anterior pillar, soft palate and mid-line), pathological findings (poorly, moderately or well differentiated), tumor type (exophytic or endophytic) were not useful prognostic factors. iii) Radiosensitivity was not reflected in the survival rate judging from the high recurrence rate (44%) after radical radiotherapy. On the other hand, local recurrence after radical resection was seen in 18% of the patients. iv) Analysis of the data supported the recommendation of surgery after preoperative radiation as the treatment for stage III patients. It seems difficult to find the best treatment modality for stage IV patients in order to improve the survival rate, and this is an issue that still remains to be resolved. v) From the study of the surgical specimens, we are unable to demonstrate a significant survival advantage of the patients with a high grade radiation effect, or patients with no vessel involvement.


Auris Nasus Larynx | 1985

Malignant Melanoma in the Maxillary Sinus—A Case Successfully Treated With Radiotherapy—

Katsufumi Hoki; Shigeo Sambe; Kohji Asakura; Kenji Morimoto; Akikatsu Kataura

In this paper, we present a case where radiotherapy was very effective against malignant melanoma. We performed a total maxillectomy as the primary treatment, but the tumor recurred rapidly in the operated wound. Then, the patient was treated with 50 Gy in twenty-five treatments. After that, the tumor disappeared remarkably. On the other hand, this malignant melanoma was of the amelanotic type. We carried out a Fontanas stain and electronic microscopy to provide the criteria for the diagnosis of malignant melanoma. The pathological character of this malignant melanoma was investigated.


Journal of Laryngology and Otology | 2007

Ossifying fibroma of the mandible with primary hyperparathyroidism due to non-familial parathyroid adenoma

Atsushi Harimaya; Hiroshi Tsubota; Katsufumi Hoki; Sato J; Kondo A; Yamada T; Nobuhiko Seki; Ikeda H; Tetsuo Himi

Ossifying fibroma is an uncommon benign osteogenic neoplasm arising from cells of the periodontal ligament, typically with a slowly progressive enlargement of the affected bone. The neoplasm sometimes presents with hyperparathyroidism, most of which cases are due to familial parathyroid tumours. We report a rare case of ossifying fibroma of the mandible which showed very rapid growth and presented with primary hyperparathyroidism due to non-familial parathyroid adenoma. Despite improvement of parathyroid dysfunction after removal of the parathyroid adenoma, the tumour continued to grow very aggressively. The case required partial mandibular resection for complete resection of the tumour, and fixation of the remaining mandible with a titanium plate.


Auris Nasus Larynx | 2004

Melanin pigmented oncocytic metaplasia of the nasopharynx

Kenichi Takano; Jun Sato; Hideaki Shirasaki; Norikazu Yamazaki; Katsufumi Hoki; Tetsuo Himi


Plastic and Reconstructive Surgery | 2003

A prefabricated osteocutaneous flap for tracheal reconstruction

Ken-ichi Homma; Tetsuo Himi; Katsufumi Hoki; Kyori Ezoe; Tomoko Shintani; Haruhiro Yamaguchi; Tatsuya Fujita


Nippon Jibiinkoka Gakkai Kaiho | 2003

Prophylactic neck dissection for submandibular gland cancer

Takeshi Beppu; Shin-etsu Kamata; Kazuyoshi Kawabata; Tomohiko Nigauri; Hiroki Mitani; Seiichi Yoshimoto; Hiroyuki Yonekawa; Kohki Miura; Hirofumi Fukushima; Tohru Sasaki; Takahide Hamano; Yuichirou Tada; Katsufumi Hoki

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Kazuyoshi Kawabata

Japanese Foundation for Cancer Research

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Akikatsu Kataura

Sapporo Medical University

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Hiroki Mitani

Japanese Foundation for Cancer Research

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Kohji Asakura

Sapporo Medical University

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Seiichi Yoshimoto

Japanese Foundation for Cancer Research

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Takeshi Beppu

Japanese Foundation for Cancer Research

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Tetsuo Himi

Sapporo Medical University

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