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Featured researches published by Hiromi Nagai.


Acta Oto-laryngologica | 2002

Treatment Effects in Patients with Squamous Cell Carcinoma of the Oral Cavity

Katsuhide Inagi; Hiroomi Takahashi; Makito Okamoto; Meijin Nakayama; Tomohiro Makoshi; Hiromi Nagai

A total of 221 patients (155 males, 66 females; stage I, n ¾ 55; stage II, n ¾ 58; stage III, n ¾ 57; stage IV, n ¾ 51) with squamous cell carcinoma of the oral cavity were studied. Tumor localization was as follows: cancer of the tongue, n ¾ 161; cancer of the oral floor, n =28; cancer of the hard palate, n ¾ 12; cancer of the buccal mucosa, n ¾ 11; and cancer of the gingiva, n ¾ 9. In order to compare the effect of different treatments, three major treatment groups were defined, namely a surgery group, a radiotherapy group and a combination treatment group. Five-year cumulative survival rates showed significant differences between stage classifications (stage I=91%, stage II=73%, stage III=63%, stage IV=47%; p <0.01) but not between tumor sites. The 5-year cumulative survival rate was highest for oral floor cancer (80%). In the early-cancer group, the 5-year cumulative survival rate for the surgery group (92%) was significantly higher ( p <0.05) than those for both the radiation (69%) and combination (71%) groups. In the advanced-cancer group, the 5-year cumulative survival rate for the surgery group (74%) was significantly higher ( p <0.05) than those for both the radiation (37%) and combination (51%) groups. No significant difference in regional control rates was observed between the treatment groups. Five-year regional control rates were 86% for cervical untreated patients with T1N0 tumors and 60% for cervical untreated patients with T2N0 tumors. Fourteen N0 cases were treated with neck dissection. Cervical metastasis was found pathologically in 2/14 (14%) of these cases. The 5-year survival rate for patients with cervical recurrences after primary tumor resection was 70% ( n ¾ 15). In contrast, the 5-year survival rate for patients with both primary tumor resection and neck dissection was 74% ( n ¾ 14) but no significant difference was observed between these 2 groups.rate .


Acta Oto-laryngologica | 2002

Multiple primary malignancies in the head and neck: a clinical review of 121 patients.

Tatsutoshi Suzuki; Hiroomi Takahashi; Kazuo Yao; Katsuhide Inagi; Meijin Nakayama; Tomohiro Makoshi; Hiromi Nagai; Makito Okamoto

A total of 121 multiple primary malignancies (quadruple, n ¾ 2; triple, n ¾ 11; and double, n ¾ 108) were treated at the Department of Otorhinolaryngology, Kitasato University Hospital between July 1972 and December 1998. Of the 108 patients with double primary malignancies, 18 had synchronous double primary malignancies (SDPM), which were defined as occurrence of the index tumor and second malignancy within 6 months of each other, and 90 had metachronous double primary malignancies (MDPM), which were defined as occurrence of the index tumor and the second malignancy separated by a period of >7 months. MDPM was subdivided into MDPM-F (head and neck malignancy occurred as the first tumor; n ¾ 55) and MDPM-S (head and neck malignancy occurred as the second tumor; n ¾ 35). Of the 55 patients with MDPM-F, 27 (49.1%) of the second malignancies were found in the digestive tract, 12 in the stomach (21.8%), 8 in the esophagus (14.5%) and 7 in lower digestive tract tumors (12.7%). The 3- and 5-year survival rates of MDPM-F were 79.2% and 62.3%, respectively. Differential diagnosis between multiple primary malignancy (MPM) and multicentric tumors is often difficult when the lesions involve the oral cavity, pharynx and esophagus. We suggest that it is beneficial to follow patients for as long as possible in order to facilitate diagnosis of tumor recurrence, metastasis and MPM.


Laryngoscope | 2006

Long-term result of the new endoscopic vocal fold medialization surgical technique for laryngeal palsy

Koichiro Nishiyama; Hajime Hirose; Takashi Masaki; Hiromi Nagai; Daimon Hashimoto; Daisuke Usui; Kazuo Yao; Koichi Tsunoda; Makito Okamoto

Objective: The conventional surgical method for a case of unilateral laryngeal nerve paralysis with large glottal gap requires an external cervical incision. In the present study, we developed an endoscopic technique of vocal fold medialization that can make the external incision unnecessary. This procedure of autologous transplantation of fascia into the vocal fold (ATFV) was developed for the successful treatment of unilateral laryngeal nerve paralysis. However, the method seemed to be effective only for patients with a relatively mild glottal gap.


Acta Oto-laryngologica | 2002

Cemento-ossifying fibroma of maxillary and sphenoid sinuses: case report and literature review.

Chunmei Cheng; Hiroomi Takahashi; Kazuo Yao; Meijin Nakayama; Tomohiro Makoshi; Hiromi Nagai; Makito Okamoto

We report a case of cemento-ossifying fibroma (COF) involving the maxillary and sphenoid sinuses and review the literature in order to study the clinical features, imaging findings and histopathologic characteristics of COF. Special care was taken to distinguish this lesion from cemento-osseous dysplasia (COD). It is almost inevitable that differential diagnosis of COD and COF will be complicated by the fact that some pathologic features are shared by both lesions. A combined study incorporating clinical, radiographic and pathologic findings is important in order to ensure an accurate diagnosis. Postoperative follow-up is essential, especially in cases where incomplete removal of the COF was performed.


Laryngoscope | 2002

Autologous transplantation of fascia into the vocal fold as a treatment for recurrent nerve paralysis

Koichiro Nishiyama; Hajime Hirose; Yoshiaki Iguchi; Hiromi Nagai; Jun Yamanaka; Makito Okamoto

Objectives To apply the technique of autologous transplantation of fascia graft into the vocal fold for glottal insufficiency due to recurrent nerve paralysis and to evaluate the results in eight patients who underwent the procedure.


Laryngoscope | 2008

Effect of Aging on Blood Flow in Rat Larynx

John A. Russell; Hiromi Nagai; Nadine P. Connor

Objective/Hypothesis: Age‐associated muscular changes and fatigue have been shown to affect phonatory function. Reductions in blood flow with aging could translate to reductions in oxidative capacity within laryngeal muscles and increased fatigability. We tested the hypothesis that there would be increased capillary red blood cell (RBC) velocity and a reduction of capillary density in the thyroarytenoid (TA) muscle of senescent rats.


Acta Oto-laryngologica | 2002

Clinical impact of using chemoradiotherapy as a primary treatment for hypopharyngeal cancer

Makito Okamoto; Hiroomi Takahashi; Kazuo Yao; Katsuhide Inagi; Meijin Nakayama; Hiromi Nagai

Eighty-eight patients with hypopharyngeal cancer who received chemoradiotherapy as the primary treatment between 1979 and 1997 were investigated. Forty-six patients who received surgery as the primary treatment were analyzed as a control group. There were no statistically significant differences regarding TN classification, tumor stage, tumor site, age or sex between the radiation and surgery groups. The 5-year cumulative survival rate of primary chemoradiotherapy was 47% and this did not differ significantly from that for the primary surgery group. The larynx was preserved in 74% of cases in the primary chemoradiotherapy group, a far better preservation rate than that in the surgery group. After primary chemoradiotherapy, complete remission (CR) was observed in 59% of cases and the average period of CR was 38 months. Among patients with residual tumor, a salvage operation was employed in 31 cases, 13 patients refused to receive surgery and 8 were inoperable. A salvage operation was performed in 35% of all cases and the 5-year cumulative survival rate was 50%. Based on the 5-year survival, primary CR, salvage and laryngeal preservation rates, we conclude that chemoradiotherapy is a good primary treatment for hypopharyngeal cancer


Annals of Otology, Rhinology, and Laryngology | 2005

Effect of Deficits in Laryngeal Sensation on Laryngeal Muscle Biochemistry

Hiromi Nagai; Fumikazu Ota; Nadine P. Connor

Swallowing deficits in elderly people are significant clinical problems and may be associated with impaired pharyngolaryngeal sensation. However, the extent to which sensory innervation affects the motor system is unclear. Our purpose was to examine differences in biochemical properties of laryngeal muscles following sensory nerve ablation. We used sodium dodecyl sulfate–polyacrylamide gel electrophoresis to evaluate laryngeal muscles of young and old Fischer 344/Brown Norway rats, and rats that underwent sensory ablation via bilateral section of the superior laryngeal nerve, internal branch (SLNi), or mixed sensory-motor nerve ablation via left-sided recurrent laryngeal nerve (RLN) section. In lateral thyroarytenoid muscle, a reduction was found in the proportion of the most rapidly contracting myosin heavy chain isoform (type 2B) with SLNi section, RLN section, and aging. Section of the SLNi did not alter the proportion of any myosin heavy chain isoform within the lateral cricoarytenoid or posterior cricoarytenoid muscles, but RLN section resulted in a reduction in the proportion of type 2B. Accordingly, alteration in biochemical properties of the lateral thyroarytenoid muscle alone was demonstrated following sensory ablation. We conclude that sensory changes may affect properties of laryngeal muscles, and may thus have an impact on motor control during critical functions, such as airway protection during swallowing.


Acta Oto-laryngologica | 2002

Expression of Epstein-Barr virus-encoded small nuclear RNA 1 in Japanese nasopharyngeal carcinomas.

Hayato Inoue; Yuichi Sato; Benio Tsuchiya; Hiromi Nagai; Hiroomi Takahashi; Toru Kameya

An examination was made of the incidence of the Epstein -Barr virus (EBV) genome and its exact localization in 39 cases of nasopharyngeal carcinoma (NPC) in Japanese patients by means of in situ hybridization (ISH) with a digoxigeninlabeled Epstein -Barr virus-encoded small nuclear RNA 1 (EBER1) oligonucleotide probe. Hybridization signals were observed in the nucleus of tumor cells in all 39 NPCs, including keratinizing carcinomas. The signals varied greatly in intensity from case to case and even from cell to cell in the same tumor, but were recognized in most tumor cells in each case. Signals could occasionally be seen in limiting number of infiltrating small lymphocytes but were absent in all tumors of the tongue, midpharynx and hypopharynx. Combined immunohistochemistry-ISH studies indicated that EBER1 signals were restricted to tumor cells positive for cytokeratin. As a result of this study, it is now possible to perform large-scale retrospective analyses using routine formalin-fixed, paraffin-embedded tissue sections and to combine ISH for the EBV genome with immunohistochemistry for cytokeratin to determine the epithelial features of EBV genome-possessing cells. All NPCs were clearly shown to be EBV-infected, thus indicating that EBV is essential for the oncogenesis of NPCs.


Acta Oto-laryngologica | 2005

Endoscopic vocal cord medialization: A new surgical technique without neck incision for laryngeal palsy

Koichiro Nishiyama; Hajime Hirose; Hiromi Nagai; Takashi Masaki; Satoshi Horiguchi; Koichi Tsunoda; Kazuo Yao; Makito Okamoto

Different types of surgery have been reported for glottal insufficiency due to unilateral vocal cord paralysis. We recently developed a new surgical technique of fascia implantation known as vocal cord medialization. This new method achieves a wide glottal gap during phonation, without the use of an external approach. This new technique is described in detail herein, together with the satisfactory results we obtained in six cases of unilateral vocal cord paralysis with a wide glottal gap during phonation. We recommend this technique in cases of unilateral vocal cord paralysis in which both a satisfactory clinical result and an aesthetically pleasing cosmetic result are required.

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Nadine P. Connor

University of Wisconsin-Madison

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