Yoshizumi Kitamoto
Gunma University
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International Journal of Radiation Oncology Biology Physics | 2003
Masatoshi Hasegawa; Masaru Kojima; Mariko Shioya; Yoshio Tamaki; Jun-ichi Saitoh; Hideyuki Sakurai; Yoshizumi Kitamoto; Yoshiyuki Suzuki; Hideo Niibe; Takashi Nakano
PURPOSE To analyze the results of radiotherapy (RT) for malignant lymphoma of the orbit and to evaluate them compared with the World Health Organization (WHO) classification published in 2001. METHODS AND MATERIALS The data from 29 patients with malignant lymphoma of the orbit treated with RT at Gunma University Hospital between 1978 and 2001 were retrospectively analyzed. Pathologic slides from 23 cases were available and were reviewed by a hematopathologist according to the WHO classification. The original and reviewed diagnoses, patient characteristics, treatment results, and complications were analyzed. In principle, patients with low-grade or indolent lymphoma were treated with RT alone, using 30 Gy as the tumor dose. Survival data were calculated using the Kaplan-Meier method. RESULTS One case that proved to be a pseudotumor was excluded from evaluation. Of the 28 cases, 25 were Stage IAE, 1 was Stage IIAE, and 2 were Stage IVAE. The median follow-up was 71 months. According to the original classification and the Working Formulation, the 5- and 10-year overall survival rate of patients with low-grade lymphoma was 94% and 73%, respectively. The corresponding rates for those with intermediate-grade lymphoma were 67% and 67% (p = 0.15). In contrast, the WHO classification showed a significant difference in the survival curves. The 5- and 10-year overall survival rate of patients with mucosa-associated lymphoid tissue (MALT) lymphoma was 100% and 88%, respectively; for diffuse large B-cell patients, the rates were both 0% (p < 0.001). In patients with MALT lymphoma, one local and four distant relapses developed; two of them >10 years after initial treatment. All of the relapsed MALT lymphomas were controlled by salvage therapy. CONCLUSION Excellent local control and survival can be achieved for patients with orbital MALT lymphoma using RT alone. A precise histopathologic diagnosis using the WHO classification and long-term follow-up for >10 years is recommended.
Journal of Clinical Gastroenterology | 2005
Hitoshi Ishikawa; Hideyuki Sakurai; Michitaka Yamakawa; Yoshihiro Saito; Yuko Nakayama; Yoshizumi Kitamoto; Masahiko Okamoto; Kousaku Harada; Masatoshi Hasegawa; Takashi Nakano
Goals and Background: There are great differences between treatment methods for early-stage esophageal cancer in institutions. Radiation therapy has been considered to be an effective modality as organ-preserving treatment of the disease. The aim of this study is to assess the effect and limitation of radiation therapy on patients with early esophageal cancer. Study: The subjects were 38 patients with stage I (T1N0M0) squamous cell carcinoma of the esophagus who had received definitive radiation therapy alone. Eleven tumors were assessed within the mucosal layer, whereas 27 tumors showed submucosal invasion by examination using endoscopic ultrasound. All patients were treated with more than 60 Gy using a conventional daily fractionation dose at 2 Gy. An additional boost with brachytherapy was performed for 20 patients, and the prescribed doses were 10 Gy (5 Gy × 2 times) with low dose rate (8 patients) and 9 Gy (3 Gy × 3 times) with high dose rate (12 patients). Outcomes and prognostic factors, including the efficacy of intraluminal brachytherapy, were investigated. Results: The cause-specific survival rate and the local control rate at 5 years were 82.6% and 86.3%, respectively. Recurrences were noted in 8 patients with submucosal cancer, but no recurrence was observed in patients with mucosal cancer. In the present study, tumor length was a statistically significant prognostic factor for cause-specific survival (P = 0.018) and tumor depth tended toward statistical significance (P = 0.073). In 27 patients with submucosal cancer, the tumor length was also statistically significant for the survival (P = 0.032). The 5-year cause-specific survival rates for the short tumor group and the long tumor group were 85.7% and 55.6%, respectively. On the other hand, the use of intraluminal brachytherapy had no significant effect on patient survival. Conclusion: Radiation therapy is very effective for early esophageal squamous cell carcinoma with tumor length less than 5 cm, but other treatment modalities, including chemoradiotherapy especially for inoperable patients, should be considered for submucosal cancer with a tumor length of 5 cm or more.
Journal of Gastroenterology and Hepatology | 2006
Hitoshi Ishikawa; Hideyuki Sakurai; Yoshio Tamaki; Tetsuo Nonaka; Michitaka Yamakawa; Yoshihiro Saito; Yoshizumi Kitamoto; Keiko Higuchi; Masatoshi Hasegawa; Takashi Nakano
Background and Aim: The aim of this study was to clarify the efficacy and limitations of radiation therapy (RT) for superficial esophageal carcinoma, and to explore the indications for more aggressive therapy, such as combined chemo‐radiotherapy.
Journal of Clinical Gastroenterology | 2003
Yoshizumi Kitamoto; Masatoshi Hasegawa; Hitoshi Ishikawa; Junichi Saito; Michitaka Yamakawa; Masaru Kojima; Takashi Nakano
&NA; Carcinomas are the most common malignancies of the esophagus. Primary malignant lymphoma involving the esophagus is rare, with only a few cases of mucosa‐associated lymphoid tissue (MALT) lymphoma of the esophagus having been reported. We report the case of a 74‐year‐old man who was diagnosed with an esophageal MALT lymphoma. Generally, MALT lymphomas are indolent and tend to disseminate slowly; however, the behavior of this disease is not known clearly, and a standard treatment has not been established because of its rarity. Although complete response was confirmed with 36‐Gy irradiation, careful follow‐up is necessary for the patient.
International Journal of Radiation Oncology Biology Physics | 2011
Katsuyuki Shirai; Yoshio Tamaki; Yoshizumi Kitamoto; Kazutoshi Murata; Yumi Satoh; Keiko Higuchi; Tetsuo Nonaka; Hitoshi Ishikawa; Hiroyuki Katoh; Takeo Takahashi; Takashi Nakano
PURPOSE To investigate the dose-volume histogram parameters and clinical factors as predictors of pleural effusion in esophageal cancer patients treated with concurrent chemoradiotherapy (CRT). METHODS AND MATERIALS Forty-three esophageal cancer patients treated with definitive CRT from January 2001 to March 2007 were reviewed retrospectively on the basis of the following criteria: pathologically confirmed esophageal cancer, available computed tomography scan for treatment planning, 6-month follow-up after CRT, and radiation dose ≥ 50 Gy. Exclusion criteria were lung metastasis, malignant pleural effusion, and surgery. Mean heart dose, mean total lung dose, and percentages of heart or total lung volume receiving ≥ 10-60 Gy (Heart-V(10) to V(60) and Lung-V(10) to V(60), respectively) were analyzed in relation to pleural effusion. RESULTS The median follow-up time was 26.9 months (range, 6.7-70.2) after CRT. Of the 43 patients, 15 (35%) developed pleural effusion. By univariate analysis, mean heart dose, Heart-V(10) to V(60), and Lung-V(50) to V(60) were significantly associated with pleural effusion. Poor performance status, primary tumor of the distal esophagus, and age ≥ 65 years were significantly related with pleural effusion. Multivariate analysis identified Heart-V(50) as the strongest predictive factor for pleural effusion (p = 0.01). Patients with Heart-V(50) <20%, 20%≤ Heart-V(50) <40%, and Heart-V(50) ≥ 40% had 6%, 44%, and 64% of pleural effusion, respectively (p < 0.01). CONCLUSION Heart-V(50) is a useful parameter for assessing the risk of pleural effusion and should be reduced to avoid pleural effusion.
International Journal of Radiation Oncology Biology Physics | 2002
Jun-ichi Saitoh; Hideyuki Sakurai; Yoshiyuki Suzuki; Hiroyuki Muramatsu; Hitoshi Ishikawa; Yoshizumi Kitamoto; Tetsuo Akimoto; Masatoshi Hasegawa; Norio Mitsuhashi; Takashi Nakano
PURPOSE The purpose of this study is to evaluate the amount of hypoxic fraction in a rodent tumor by means of polarographic oxygen electrode, phosphorus-31 magnetic resonance spectroscopy (31P-MRS), and a newly synthesized hypoxic marker, beta-D-iodinated azomycin galactopyranoside (beta-D-IAZGP). We also investigated the radiosensitivity for tumors of different weights. METHODS AND MATERIALS Murine mammary carcinoma cells, FM3A, were subcutaneously implanted into the back of 5-week-old male C3H/He mice. beta-D-IAZGP radiolabeled with 123I or with 125I was injected intravenously into tumor-bearing mice, and marker distribution was measured by nuclear medicine procedures. Radiosensitivity of the tumor was measured by the in vivo/in vitro clonogenic assay. Tumor oxygenation status was also measured directly by polarographic oxygen electrodes and indirectly estimated from 31P-MR spectra. RESULTS Higher accumulation of 123I-beta-D-IAZGP was observed in the tumors than in normal tissues at 24 h after administration. As to biodistribution of 125I-beta-D-IAZGP, the tumor/blood ratio varied widely, but correlated significantly with tumor weight. Mean oxygen pressure (pO2) values and ratios of nucleoside triphosphate beta to inorganic phosphate (beta-ATP/Pi) and of phosphocreatine to inorganic phosphate (PCr/Pi) decreased significantly with the increase in tumor volume. As tumor volume increased, the surviving fraction of cells from tumors irradiated in vivo increased significantly. CONCLUSIONS The increase in tumor volume was significantly correlated with a reduction in mean pO2, a decrease in the ratios of beta-ATP/Pi or PCr/Pi, an increase in uptake of beta-D-IAZGP, and an increase in radioresistance. Because the uptake of beta-D-IAZGP can be measured noninvasively by nuclear medicine techniques, it could be clinically useful for monitoring hypoxia in human tumors.
International Journal of Radiation Oncology Biology Physics | 2010
Hitoshi Ishikawa; Tetsuo Nonaka; Hideyuki Sakurai; Yoshio Tamaki; Yoshizumi Kitamoto; Takeshi Ebara; Mariko Shioya; Shin-ei Noda; Katsuyuki Shirai; Yoshiyuki Suzuki; Takeo Takahashi; Takashi Nakano
PURPOSE To assess the efficacy of radiation therapy (RT) by using intraluminal brachytherapy (IBT) combined with external beam RT (EBRT) for submucosal esophageal cancer. METHODS AND MATERIALS Between 1991 and 2005, 59 consecutive patients received definitive RT without chemotherapy. IBT was performed after patients completed EBRT as a booster therapy for 17 patients, using low-dose-rate Cs-137 sources until 1997, and for 19 patients, using high-dose-rate Ir-192 sources thereafter. The long-term outcomes were investigated with a median follow-up time of 61 months. RESULTS Logoregional recurrences and distant metastases were observed in 14 patients and in 2 patients in the lung, respectively, and 5 patients were rescued by salvage treatments. The 5-year logoregional control and cause-specific survival rates were 75% and 76%, respectively. The 5-year cause-specific survival rate in the EBRT group was 62%, whereas the corresponding rate in the IBT group was 86% (p = 0.04). Multivariate analysis revealed that IBT was the most powerful predictor of survival but did not reach a significant level (p = 0.07). There were five esophageal ulcers in the IBT group, but no ulcers developed with small fractions of 3 Gy. Grade 2 or higher cardiorespiratory complications developed in 2 patients (5.6%) in the IBT group and in 3 patients (13.0%) in the EBRT group. CONCLUSIONS Combining IBT with EBRT is suggested to be one of the preferable treatment modalities for medically inoperable submucosal esophageal cancer because of its preferable local control and survival probabilities, with appreciably less morbidity.
International Journal of Radiation Oncology Biology Physics | 1998
Hideyuki Sakurai; Norio Mitsuhashi; Osamu Murata; Yoshizumi Kitamoto; Yoshihiro Saito; Masatoshi Hasegawa; Tetsuo Akimoto; Takeo Takahashi; Sachiko Nasu; Hideo Niibe
PURPOSE Phosphorus-31 magnetic resonance spectra (31P-MRS) were obtained from highly apoptotic murine lymphoma xenografts before and up to 24 hr following graded doses of radiation ranging from 2 to 30 Gy. Radiation-induced apoptosis was also estimated up to 24 hr by scoring apoptotic cells in tumor tissue. METHODS AND MATERIALS Highly apoptotic murine lymphoma cells, EL4, were subcutaneously transplanted into C57/BL mice. At 7 days after transplantation, radiation was given to the tumor with a single dose at 3, 10, and 30 Gy. The beta-ATP/Pi, PME/Pi, and beta-ATP/PME values were calculated from the peak area of each spectrum. Radiation-induced apoptosis was scored with counting apoptotic cells on hematoxylin and eosin stained specimens (% apoptosis). RESULTS The values of % apoptosis 4, 8, and 24 hr after radiation were 21.8, 19.6, and 4.6% at 3 Gy, 35.1, 25.6, and 14.8% at 10 Gy, 38.4, 38.0, and 30.6% at 30 Gy, respectively (cf. 4.4% in control). There was no correlation between early change in beta-ATP/Pi and % apoptosis at 4 hr after radiation when most of the apoptosis occurred. An early decrease in PME/Pi was observed at 4 hr after radiation dose at 30 Gy. For each dose, the values of beta-ATP/Pi 24 hr after radiation were inversely related to radiation dose. CONCLUSION The increase in beta-ATP/Pi observed by 31P-MRS was linked to the degree of histological recovery from radiation-induced apoptosis.
Lung | 2006
Hitoshi Ishikawa; Yuko Nakayama; Yoshizumi Kitamoto; Tetsuo Nonaka; Hidemasa Kawamura; Katsuyuki Shirai; Hideyuki Sakurai; Kazushige Hayakawa; Hideo Niibe; Takashi Nakano
Japanese randomized trials showed that there was a significant impact on survival from stage I adenocarcinoma (AD) of the lung by adjuvant chemotherapy with uracil-tegaful after complete resection but there was no effect for patients with squamous cell carcinoma (SQ). The purpose of this study was to examine the correlation of tumor histology and clinical outcome of radiation therapy (RT) for stage I non-small-cell lung cancer (NSCLC) and to consider the necessity of adjuvant chemotherapy after RT for these patients. The subjects were 83 patients, 54 with SQ and 29 with AD; they had received definitive RT with the total dose ranging from 60 to 80 Gy with conventional fractionation at a daily dose of 2 Gy. The differences between SQ and AD with respect to survival and recurrence pattern were investigated. The 5-year overall survival and cause-specific survival rates were 26.5% and 49.1%, respectively. No difference in survival was observed between SQ and AD patients, and the recurrence rates were almost identical (44% for SQ and 45% for AD). However, the 5-year primary control rate of SQ was significantly poorer than that of AD (SQ: 61.5%; AD: 87.6%; p = 0.03). Conversely, the 5-year metastasis-free survival rate of SQ was significantly better than that of AD (SQ: 88.2%; AD: 53.0%; p = 0.005). The different failure pattern, according to tumor histology, indicates that taking into consideration the difference in their clinical behaviors would also be important for planning RT and surgery for early lung cancer.
International Journal of Radiation Biology | 2005
Hideyuki Sakurai; Yoshizumi Kitamoto; Jun-ichi Saitoh; Tetsuo Nonaka; Hitoshi Ishikawa; Hiroki Kiyohara; Mariko Shioya; Masahide Fukushima; Tetsuo Akimoto; Masatoshi Hasegawa; Takashi Nakano
Purpose: We investigated whether the attenuation of chronic thermotolerance by KNK437, a heat shock protein inhibitor, can modify the effect of thermal radiosensitization in mild temperature hyperthermia (MTH) combined with low dose-rate irradiation (LDRI). Materials and methods: The human lung adenocarcinoma cell line A549 was simultaneously exposed to LDRI with MTH at 41°C and KNK437 at a dose of 100 μM. Cell survival was estimated by a clonogenic assay. Cell cycle change during treatment was analyzed by flow cytometry. Expression levels of the heat shock proteins hsp72, hsp27 and heat shock factor 1 (HSF-1) were measured by Western blotting. Results: KNK437 inhibited the expression of inducible hsp72 and hsp27, but produced no change in the mobility shift of HSF-1. The cytotoxicity of LDRI was enhanced by MTH. The survival curve for LDRI + MTH revealed no development of chronic thermotolerance up to 48 h. Simultaneous LDRI and KNK437 treatment also resulted in enhanced cell killing. The radiosensitizing effect of KNK437 was enhanced by simultaneous exposure of the cells to MTH. Flow cytometry analysis of cell cycle progression demonstrated marked G2 arrest and mild G1 arrest with LDRI alone, but mild G1 arrest with MTH alone, and mild G2-M, S-phase accumulation with KNK437 alone. The marked G2 arrest caused by LDRI was partially suppressed by the addition of MTH, and was also suppressed by KNK437 treatment. Conclusions: Exposure of A549 cells to KNK437 caused inhibition of hsp72 and hsp27 expression. The addition of KNK437 increased not only thermosensitivity to MTH, but also radiosensitivity to LDRI. KNK437 also enhanced the MTH-induced radiosensitization under these experimental conditions.