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Featured researches published by Takushi Dokiya.


International Journal of Radiation Oncology Biology Physics | 1999

Multi-institutional randomized trial of external radiotherapy with and without intraluminal brachytherapy for esophageal cancer in Japan

Tomohiko Okawa; Takushi Dokiya; Masamichi Nishio; Yoshio Hishikawa; Kozo Morita

PURPOSE With the aim of improving the results of treatment of esophageal cancer, we designed this multi-institutional, randomized trial to establish the optimal irradiation method in radical radiation therapy for esophageal cancer by clinically evaluating external irradiation alone and in combination with intraluminal brachytherapy. METHODS AND MATERIALS The study population consisted of patients with squamous cell carcinoma who were expected to be successfully treated with radical radiation therapy. The patients who could be given intraluminal brachytherapy at the end of external irradiation of 60 Gy were stratified into 2 groups. Patients assigned to receive external irradiation alone received boost irradiation of 10 Gy/week on a schedule similar to the previous one, and with the same or smaller irradiation field. Intraluminal brachytherapy was performed, as a rule, with the reference dose point set at a depth of 5 mm of the esophageal submucosa, and a total of 10 Gy was irradiated at a daily dose of 5 Gy, on a once-weekly schedule with low-dose-rate or high-dose-rate brachytherapy equipment. RESULTS A total of 103 patients were registered, 94 of whom were analyzable, with 8 ineligible, and 1 for whom complete information was unavailable. The overall cumulative survival rate was 20.3% at 5 years. The cause-specific survival rate was 31.8% at 5 years. The cause-specific survival rate at 5 years was 27% in the external irradiation alone group and 38% in intraluminal brachytherapy combined group. There was no significant difference between the 2 groups (p = 0.385). However, in the patients with 5 cm or less tumor length, the cause-specific survival rate was 64% at 5 years in the intraluminal brachytherapy combined group, which showed a significant improvement over 31.5% in the external irradiation alone group (p = 0.025). In the patients with Stage T1 and T2 disease, cause-specific survival rates tended to be better in the intraluminal brachytherapy combined group than in the external irradiation alone group (p = 0.088). In the patients with more than 5 cm tumor length or Stage T3-4 disease, there were no significant differences between the two groups by treatment methods (p = 0.290). The incidence of early and late complications did not differ according to whether intraluminal brachytherapy was used. CONCLUSION For the purpose of establishing the usefulness of intraluminal brachytherapy, further prospective randomized studies are necessary to evaluate the efficacy in tumors with short length and those with shallow invasion, or to assess the usefulness of intraluminal brachytherapy, as additional irradiation in large advanced tumors have been shown to have disappeared by diagnostic imaging after chemoradiotherapy with 60 Gy/6w external irradiation.


Cancer | 1982

Computed tomography of malignant tumors of the nasal cavity and paranasal sinuses

Makoto Kondo; Masatoshi Horiuchi; Hayao Shiga; Yukio Inuyama; Takushi Dokiya; Yasunori Takata; Shoji Yamashita; Kunio Ido; Yutaka Ando; Yoshiro Iwata; Shozo Hashimoto

Staging of malignant tumors of the nasal cavity and paranasal sinuses by computed tomography (CT) was studied in a total of 49 patients, 33 with squamous cell carcinoma and 16 with tumors of other histologic types. Involved sites by the tumor were studied, and clinical staging was made using CT findings alone according to AJC classification for maxillary sinus tumors. Surgical findings for comparison were available for most cases. Of 33 squamous cell carcinomas and of 16 tumors with other histologic types, the maxillary sinus was the site of origin in 29 and eight, respectively. Of these 37 maxillary sinus tumors, 11 were staged T3, 26 T4, and none was staged T1 or T2. None of these tumors were down staged, and one T3 was upstaged after surgical procedures, although all sinuses were not explored in some cases. Sinusitis due to obstruction was indistinguishable from the tumor without bone destruction. And the determination of the site of origin was difficult in some cases. Despite these, CT should be used for pretreatment evaluation of the tumors of these sites.


Cancer | 1989

Phase II randomized clinical trial of LC9018 concurrently used with radiation in the treatment of carcinoma of the uterine cervix. Its effect on tumor reduction and histology

Tomohiko Okawa; Midori Kita; Tatsuo Arai; Kouyo Iida; Takushi Dokiya; Yoshihiro Takegawa; Yutaka Hirokawa; Kazuto Yamazaki; Shozo Hashimoto

The clinical efficacy of LC9018, a biological response modifier prepared from heat‐killed Lactobacillus casei YIT9018, used in combination with radiation was studied in a randomized controlled trial on 61 patients with carcinoma of the uterine cervix of Stage IIB or III. The combination therapy with LC9018 demonstrated a significant effect on tumor reduction, compared with radiation therapy alone, at the cumulative doses of 15‐Gy and 30‐Gy external irradiation (P < 0.05). Histologic study confirmed that LC9018 also enhanced the therapeutic effect of the irradiation. Moreover, LC9018 seemed to be useful in protecting the patients from leukopenia during radiotherapy. This study suggests that LC9018, when used in combination with radiotherapy, will be an effective adjuvant immunotherapeutic agent. More studies in a large series of patients will, however, be needed to establish its long‐term efficacy, safety, and effects on both prognosis and enhancing radiotherapy.


International Journal of Radiation Oncology Biology Physics | 1986

Local control of squamous cell carcinoma of the mobile tongue: an experience of different modalities

Makoto Kondo; Shozo Hashimoto; Takushi Dokiya; Yukio Inuyama; Yasushi Murakami; Tetsuo Nagai; Soichiro Asanami; Kimio Fukutake

From 1966 through 1983, 163 patients with squamous cell carcinoma of the mobile tongue were treated. Fifty-two patients were staged as T1N0, 77 as T2N0, 14 as T2N+, 8 as T3N0, 7 as T3N+, and 5 as T4. The follow-ups were complete. Treatment modalities varied considerably during that period, because of increasing difficulty to use radioactive sources by regulations. All T3N+ and T4 patients died shortly after treatment. Five year absolute survivals for the T1N0, T2N0, T2N+, and T3N0 patients were 87%, 60%, 27% and 63%, respectively. Local recurrence free survivals at 5 years for the T1N0, T2N0, T2N+, and T3N0 patients were 72, 48, 58, and 88%, respectively. Local recurrence free survivals seemed to be better with Ra-226 needling +/- external irradiation (EXT) than other modalities. Because many patients with local recurrence were salvaged, ultimate local-disease-free survivals should also be considered. They were 96 and 70% at 5 years for the T1N0 patients treated with Ra-226 +/- EXT, and with surgery +/- EXT, respectively; the corresponding figures for the T2N0 patients were 83 and 64%. For these reasons, Ra-226 needling may be preferable to other modalities as initial treatment. Although cervical failures did not develop after 2 years of treatment, late local recurrences were rather common, even after 5 years. Long-term follow-up is mandatory for the management of the patients, and analyzing and comparing the results.


Acta Oncologica | 1992

Primary non-Aids Related Brain Lymphoma: Patterns of failure following radiotherapy

Minoru Uematsu; Makoto Kondo; Takushi Dokiya; Yoshihisa Oguchi; Shigeo Toya; Chikao Torikata; Toru Kuribayashi; Shozo Hashimoto

Thirteen patients with primary brain lymphoma (PBL) were treated with radiotherapy. Three patients also had ocular involvement with retinal masses at initial presentation. All but one patient received conventional whole brain irradiation and, in addition, spinal irradiation, intrathecal methotrexate or orbital irradiation were given in two, two and four patients respectively. The radiation doses for involved sites ranged from 40 to 65 Gy, and for prophylactic sites from 30 to 50 Gy. After radiotherapy, all patients had complete regression of the tumor on computed tomography. Nine patients relapsed, 5 of them with brain recurrence. Two patients had ocular recurrence exclusively as their first relapse. The remaining two relapsing patients had bone lesions. One patient died intercurrently. As a result, only three patients are alive and free of disease after 16 to 36 months and all three received some adjuvant treatment in addition to whole brain irradiation.


Radiotherapy and Oncology | 1992

The role of radiotherapy in the treatment of primary mediastinal seminoma

Minoru Uematsu; Makoto Kondo; Takushi Dokiya; Seiichi Tamai; Yutaka Ando; Shozo Hashimoto

Nine patients with primary mediastinal seminoma were treated with radiotherapy. All patients achieved complete response on chest radiography. None of the three patients treated with whole mediastinal irradiation relapsed. Four of the six patients with involved-field irradiation had marginal relapses, suggesting the efficacy of the whole mediastinal irradiation.


Acta Oncologica | 1983

Value of computed tomography for radiation therapy of tumors of the nasal cavity and paranasal sinuses.

Makoto Kondo; Masatoshi Horiuchi; Yukio Inuyama; Takushi Dokiya; Taketo Tsutsui; Y. Iwata; M. Endo; Teisuke Hashimoto; Etsuo Kunieda; Shozo Hashimoto

The role of computed tomography (CT) in connection with irradiation was evaluated in 60 patients with malignant tumors of the nasal cavity and paranasal sinuses. The extent of the tumors was well demonstrated at CT. The infratemporal fossa was involved in 33 patients, extension to the intracranial cavity was found in 6, and in 16 extension to the contralateral side. Such information is of great help in radiation treatment planning. On the other hand, CT was less valuable for evaluating the effect of radiation therapy.


Acta Oncologica | 1982

Radiation Therapy of Early Glottic Carcinomaa a Japanese Experience

Makoto Kondo; Yasushi Murakami; S. Saito; Takushi Dokiya; H. Miyamoto; Yutaka Ando; Shoji Yamashita; Shozo Hashimoto

From 1969 and through 1979, 105 patients with T1 N0M0 and T2 N0M0 glottic carcinoma were treated with irradiation alone. The minimum follow-up period was 2 years, and only one patient was lost to follow-up. There were 62 T1a lesions, 14 T1b, 19 T2 with normal mobility, and 10 T2 with impaired mobility; relapses occurred in 10, 4, 1 and 3 patients, respectively. All but one patient who relapsed had local recurrence with or without nodal or distant spread. One patient had only nodal metastasis. Six of the 18 relapses were successfully cured by surgery. None of the patients who had nodal or distant spread survived. The relapse rates had no clear relation to total dose or TDF value. T1 lesions treated through larger fields (greater than or equal to 25 cm2) had a lower relapse rate than lesions treated through smaller fields, but the difference was not statistically significant.


Clinical Nuclear Medicine | 1986

Radionuclide imaging of two patients with metastasis to a distal phalanx of the hand.

Shigeru Kosuda; Takehiko Gokan; Kohe Tamura; Takushi Dokiya; Atsushi Kubo; Shozo Hashimoto

Although skeletal metastases from malignant neoplasms are common, the spread of cancer to the distal phalanx of the hand is quite rare. We have presented two cases with a distal phalangeal metastasis which could be definitely detected by radionuclide imaging.


International Journal of Radiation Oncology Biology Physics | 1998

Prospective study of external radiotherapy with and without intracavitary brachy-therapy for esophageal cancer in Japan

Tomohiko Okawa; Masamichi Nishio; O.M. Kita; Yutaka Hirokawa; Takushi Dokiya; Shogo Yamada; Hideo Niibe

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Tomohiko Okawa

Memorial Hospital of South Bend

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Minoru Uematsu

National Defense Medical College

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Shigeru Kosuda

National Defense Medical College

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