Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Katsunori Yagi is active.

Publication


Featured researches published by Katsunori Yagi.


Auris Nasus Larynx | 2001

Clinical study of adenoid cystic carcinoma of the head and neck.

Dai Takagi; Satoshi Fukuda; Yasushi Furuta; Katsunori Yagi; Akihiro Homma; Tatsumi Nagahashi; Yukio lnuyama

OBJECTIVE We examined prognostic factors and outcome of the primary treatment in patients with adenoid cystic carcinoma (ACC) of the head and neck. METHODS Twenty patients with ACC of the head and neck who had been treated in our institution from 1985 to 1998 were enrolled in this study. Disease-specific survival rate was analyzed by the Kaplan-Mejer method, and the log-rank test was applied to compare the survival rates. RESULTS The overall 5- and 10-year survival rates determined by Kaplan-Meier analysis were 81 and 57%, respectively. Patients with major salivary gland ACC obtained the best 10-year survival rate (83%), while those with paranasal sinus ACC had the worst survival rate (33%). Predominance of the solid component on pathological examination might indicate a worse prognosis. Our study revealed that postoperative radiotherapy could yield better control of the lesion focus. Chemotherapy failed in some patients and was not dramatically effective by itself. CONCLUSIONS The long-term prognosis of ACC was poor. Long-term follow-up is necessary for better prognosis of patients treated with radical treatment regimens.


Auris Nasus Larynx | 2001

Correlation of clinicopathological parameters and biological markers related to apoptosis and proliferative activity with a clinical outcome in squamous cell carcinoma of the larynx treated with concurrent chemoradiotherapy

Akihiro Homma; Yasushi Furuta; Nobuhiko Oridate; Yuko Nakano; Katsunori Yagi; Tatsumi Nagahashi; Satoshi Fukuda; Yukio Inuyama

OBJECTIVE This study was designed to determine whether biological markers related to apoptosis or proliferative activity are associated with the clinical outcome in patients with squamous cell carcinoma (SCC) of the larynx treated with concurrent chemoradiotherapy. METHODS Immunostaining with antibodies specific to p53, bcl-2, bax, and MIB-1 was performed to evaluate expression of these proteins in formalin-fixed, paraffin-embedded specimens of 59 patients treated with concurrent chemoradiotherapy (carboplatin, 100 mg/m2, four to six times every week; total radiation dose of 40-65 Gy over 4-6.5 weeks). RESULTS Multivariate analysis indicated that nodal status was a significant indicator of overall survival (OS: P = 0.001). Patients with bcl-2 positive tumors had better OS than those with bcl-2 negative tumors in both univariate (P = 0.002) and multivariate analyses (P < 0.001 ). In the univariate analysis, a considerable difference in OS was observed among the expressions of bax (P = 0.077), MIB-1 proteins (P = 0.071). and OS. but the difference was not statistically significant. CONCLUSION This study indicates that nodal status is the major prognostic tactor in patients with SCC of the larynx treated with concurrent chemoradiotherapy. These results provide useful information for predicting prognosis. Further analysis of biological factors is needed to evaluate the value as predictive markers.


International Journal of Clinical Oncology | 2006

Watch-and-see policy for the clinically positive neck in head and neck cancer treated with chemoradiotherapy.

Akihiro Homma; Yasushi Furuta; Nobuhiko Oridate; Fumiyuki Suzuki; Eisaku Higuchi; Takeshi Nishioka; Hiroki Shirato; Tatsumi Nagahashi; Katsunori Yagi; Satoshi Fukuda

BackgroundChemoradiotherapy (CRT) is becoming more widely used for head and neck cancer. However, there are conflicting theories regarding the best management options for patients with advanced nodal disease.MethodsFrom 1990 to 1999, we treated 96 patients with N1-N2 neck disease by concomitant CRT for organ preservation, using weekly carboplatin or a low daily dose of cisplatin, followed by a “watch-and-see” policy for the neck. In the present study, we retrospectively analyzed the treatment outcome in 63 of these patients who received definitive CRT for primary and neck diseases and were monitored for neck disease for more than 2 years.ResultsIn 12 of the 22 (55%) N1 patients, CRT successfully controlled the neck disease. CRT was successful in 18 of the 41 (44%) patients with N2 disease. In 6 (60%) of 10 patients with residual or recurrent N1 disease, salvage surgery was successful. Of the 23 patients with residual or recurrent N2 disease, salvage surgery was successful in 8 patients (35%). The group of patients who showed a clinical complete response (CCR) to CRT had an overall survival rate of 62.4% (33 patients), whereas for those with a less than complete response (<CCR), the figure was 13.3% (30 patients; P < 0.001). Among the <CCR-neck group, patients who underwent neck dissection (ND) as well (n = 20) did not have a significantly better overall survival than those who did not undergo ND (n = 10; P = 0.069).ConclusionWe propose a treatment plan for neck disease that involves observing the neck closely following CRT. ND should be planned only when there is evidence that neck disease exists.


Auris Nasus Larynx | 2001

A clinical study on the cervical lymph node metastasis of maxillary sinus carcinoma

Katsunori Yagi; Satoshi Fukuda; Yasushi Furuta; Nobuhiko Oridate; Akihiro Homma; Tatsumi Nagahashi; Yukio Inuyama

OBJECTIVE To improve the management of maxillary sinus carcinoma, we retrospectively investigated the significance of cervical lymph node metastasis in our treated cases and discussed how to deal with the cervical lymph node metastasis as a prognostic factor. METHODS Medical records of 118 patients with maxillary sinus carcinoma diagnosed and treated in our institute from 1982 to 1997 were retrospectively reviewed. Tumors were staged according to UICC classification 1987. The cumulative survival was analyzed by the Kaplan-Meier method. Generally, the patients had undergone preoperative radiotherapy and surgery. We examined the cervical lymph node metastasis detected at the first examination and the subsequent cervical lymph node metastasis in relation to the prognoses. RESULTS The incidence of cervical lymph node metastasis at the initial diagnosis was 7.9% (n = 9), and that of secondary cervical lymph node metastasis without recurrence at the primary site after the first treatment was 8.3% (n = 9). In most cases, we observed metastasis to the lymph nodes in the submandibular region and in the jugular chain. The result of treatment of cervical lymph node metastasis was grave. Among the patients with cervical lymph node metastasis detected at the first examination, four patients developed local recurrence and three patients developed distant metastasis. On the other hand, among those with secondary cervical metastasis, three patients developed neck recurrence and three patients developed distant metastasis, but no local recurrence. CONCLUSIONS In the cervical metastasis of maxillary sinus carcinoma, it is important to treat the primary lesion completely. In addition to it. we should control cervical metastasis and careful neck dissection is required. For the patients with cervical lymph node metastasis, it is necessary to consider the further treatment of distant metastasis.


Auris Nasus Larynx | 2001

A rare aneurysmal bone cyst of the maxillary sinus: a case report

Fumiyuki Suzuki; Satoshi Fukuda; Katsunori Yagi; Eiji Chida; Yukio Inuyama

Aneurysmal bone cyst (ABC) is a non-neoplastic expansile bone lesion that is common in the long bones; only 2% occurs in the head and neck. We present a case of ABC in a 23-year-old male and describe the clinical and radiological features, histopathology and treatment. Magnetic resonance imaging (MRI) demonstrated multiple internal septations, cysts with fluid-fluid levels of varying intensity, and an intact rim of low-intensity signal completely surrounding the lesion. The tumor was removed by enucleation with resection of the lateral nasal cavity. Histopathologic diagnosis was ABC and fibrous dysplasia. We suggest that MRI is very useful for the diagnosis of ABC. ABC is thought to follow other lesions, and thus when treating ABC, it is important to determine whether any pre-existing lesion has preceded or not; in particular, if the lesion site is in the head and neck region.


Auris Nasus Larynx | 2001

A study of piriform sinus fistula cases

Hiromitsu Hatakeyama; Akihiro Homma; Tatsumi Nagahashi; Nobuhiko Oridate; Katsunori Yagi; Satoshi Fukuda; Yukio Inuyama

We have experienced five cases of piriform sinus fistula for the last 10 years. It is a relatively rare disease, and partly because of poor understanding of the disease, in one case infection had repeatedly recurred without being adequately treated for over 20 years, and in most cases there was a long time lapse before the diagnosis. In another case, it was difficult to image the fistula with contrast medium and fistulectomy was performed without identifying it on imaging. We have applied various devices to those cases where imaging of fistula was difficult, and achieved complete resection of fistula and have not observed recurrences of infection after resection.


Plastic and Reconstructive Surgery | 2003

reconstruction Following Total Laryngopharyngoesophagectomy and Extensive Resection of the Superior Mediastinum

Yuhei Yamamoto; Hidehiko Minakawa; Satoshi Fukuda; Yasushi Furuta; Katsunori Yagi; Shunichi Okushiba; Toshiji Motohara

&NA; Our experience with four patients who underwent immediate reconstruction following total Iaryngopharyngoesophagectomy and extensive resection of the superior mediastinum is presented. The reconstructive procedures included free jejunal graft or microvascularly augmented gastric pedicle for esophageal reconstruction, pectoral fasciocutaneous or myocutaneous flap for tracheal reconstruction, and mesenteric flap connected with jejunal graft, omental flap, or pectoral flap for protection of the great vessels and obliteration of the dead space in the cervical and superior mediastinal region. The reconstructive procedures were successful, and no pharyngocutaneous fistula, mediastinitis, or great vessel rupture was noted in any patient. There was one patient who developed lung edema and liver dysfunction postoperatively. Combinations of reconstructive procedures using wellvascularized soft tissues can be expected to provide welltolerated reconstruction following extensive cervical and superior mediastinal resection.


Auris Nasus Larynx | 2001

Concurrent chemotherapy and radiotherapy as initial treatment for stage II supraglottic squamous cell carcinoma

Tatsumi Nagahashi; Satoshi Fukuda; Akihiro Homma; Katsunori Yagi; Yasushi Furuta; Yukio Inuyama

OBJECTIVE To evaluate the efficacy and safety of concurrent carboplatin (CBDCA) and radiotherapy for laryngeal carcinoma. we investigated survival rates and laryngeal preservation rates in patients with this treatment modality and those with radiation therapy only. METHODS We underwent chemotherapy with CBDCA and conventional radiotherapy concurrently to 17 patients with untreated stage II (T2NOM0) supraglottic squamous cell carcinoma since November 1990. CBDCA (100 mg/m2) was administered intravenously once a week concurrently with radiotherapy (2.5 Gy/fr, 4 times a week). At the dose of 40 Gy, the results were evaluated, and some of the patients underwent planned surgery and others continued the radiotherapy up to 65 Gy. RESULTS Overall 5-year survival rate by Kaplan-Meier method was 81.1%. Actual laryngeal preservation rate was 76.0%. Toxicity over grade III was noticed in two patients. Compared with 14 cases of historical controls, which were treated by radiation therapy alone between 1988 and 1990, the cases with concurrent radiotherapy and chemotherapy had statistically significant advantage in overall successful laryngeal preservation rate (P < 0.05), whereas the two groups were not significantly different in the overall 5-year survival rate.


Practica oto-rhino-laryngologica | 2007

Sarcoidosis of the Nasal Cavity : A Case Report

Hiroaki Netsu; Katsunori Yagi; Eiji Chida; Nobuhiko Oridate

Although sarcoidosis is a systemic disease, the involvement of the nasal cavity is fairly uncommon. We present a 27-year-old female whose final diagnosis was nasal sarcoidosis. Nasal obstruction was the sole symptom at her first presentation. She underwent deviatomy of the nasal septum and submucosal turbinectomy. The pathological findings suggesting sarcoid granulomatosis indicated a whole body examination. No lesion in the lung, eye and skin was found at that time. Because of her deteriorating nasal lesions such as acute frontal sinusitis and recurrence of the nasal obstruction, she underwent another biopsy about a 18 months after the first surgery. The pathological findings suggested sarcoid granulomatosis and a second whole body examination was performed. The presence of skin, eye and chest lesions in the examinations lead to the final diagnosis of sarcoidosis originating from the nasal cavity. Treatment with local steroids decreased her symptoms. A close follow-up was planned due to the chronic and progressive course of the lesions of her nasal cavity.


Clinical Cancer Research | 1999

Prognostic Significance of Clinical Parameters and Biological Markers in Patients with Squamous Cell Carcinoma of the Head and Neck Treated with Concurrent Chemoradiotherapy

Akihiro Homma; Yasushi Furuta; Nobuhiko Oridate; Yuko Nakano; Gen Kohashi; Katsunori Yagi; Tatsumi Nagahashi; Satoshi Fukuda; Kazuaki Inoue; Yukio Inuyama

Collaboration


Dive into the Katsunori Yagi's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kazuyoshi Kawabata

Japanese Foundation for Cancer Research

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge