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Featured researches published by Sunao Tokumaru.


International Journal of Radiation Oncology Biology Physics | 2012

Prospective multi-institutional study of definitive radiotherapy with high-dose-rate intracavitary brachytherapy in patients with nonbulky (<4-cm) stage i and II uterine cervical cancer (JAROG0401/JROSG04-2)

Takafumi Toita; Shingo Kato; Yuzuru Niibe; Tatsuya Ohno; Tomoko Kazumoto; Takeshi Kodaira; Masaaki Kataoka; Naoto Shikama; Masahiro Kenjo; Sunao Tokumaru; Chikako Yamauchi; Osamu Suzuki; Hideyuki Sakurai; Hodaka Numasaki; Teruki Teshima; Masahiko Oguchi; Yoshikazu Kagami; Takashi Nakano; Masahiro Hiraoka; Norio Mitsuhashi

PURPOSE To determine the efficacy of a definitive radiotherapy protocol using high-dose-rate intracavitary brachytherapy (HDR-ICBT) with a low cumulative dose schedule in nonbulky early-stage cervical cancer patients, we conducted a prospective multi-institutional study. METHODS AND MATERIALS Eligible patients had squamous cell carcinoma of the intact uterine cervix, Federation of Gynecologic Oncology and Obstetrics (FIGO) stages Ib1, IIa, and IIb, tumor size <40 mm in diameter (assessed by T2-weighted magnetic resonance imaging), and no pelvic/para-aortic lymphadenopathy. The treatment protocol consisted of whole-pelvis external beam radiotherapy (EBRT) of 20 Gy/10 fractions, pelvic EBRT with midline block of 30 Gy/15 fractions, and HDR-ICBT of 24 Gy/4 fractions (at point A). The cumulative biologically effective dose (BED) was 62 Gy(10) (α/β = 10) at point A. The primary endpoint was the 2-year pelvic disease progression-free (PDPF) rate. All patients received a radiotherapy quality assurance review. RESULTS Between September 2004 and July 2007, 60 eligible patients were enrolled. Thirty-six patients were assessed with FIGO stage Ib1; 12 patients with stage IIa; and 12 patients with stage IIb. Median tumor diameter was 28 mm (range, 6-39 mm). Median overall treatment time was 43 days. Median follow-up was 49 months (range, 7-72 months). Seven patients developed recurrences: 3 patients had pelvic recurrences (2 central, 1 nodal), and 4 patients had distant metastases. The 2-year PDPF was 96% (95% confidence interval [CI], 92%-100%). The 2-year disease-free and overall survival rates were 90% (95% CI, 82%-98%) and 95% (95% CI, 89%-100%), respectively. The 2-year late complication rates (according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer of Grade ≥ 1) were 18% (95% CI, 8%-28%) for large intestine/rectum, 4% (95% CI, 0%-8%) for small intestine, and 0% for bladder. No Grade ≥ 3 cases were observed for genitourinary/gastrointestinal late complications. CONCLUSIONS These results suggest that definitive radiotherapy using HDR-ICBT with a low cumulative dose schedule (BED, 62 Gy(10) at point A) can provide excellent local control without severe toxicity in nonbulky (<4-cm) early-stage cervical cancer.


Neuro-oncology | 2008

Primary central nervous system lymphoma in Japan: changes in clinical features, treatment, and prognosis during 1985-2004.

Yuta Shibamoto; Hiroyuki Ogino; Gen Suzuki; Mitsuhiro Takemoto; Norio Araki; Koichi Isobe; Emiko Tsuchida; Katsumasa Nakamura; Masahiro Kenjo; Kazunori Suzuki; Masako Hosono; Sunao Tokumaru; Shunichi Ishihara; Eriko Kato; Noriko; Naofumi Hayabuchi

We have conducted nationwide surveys of primary central nervous system lymphoma (PCNSL) treated since 1985. In the present study, we newly collected data between 2000 and 2004 and investigated changes in clinical features and outcome over time. A total of 739 patients with histologically proven PCNSL under going radiotherapy were analyzed. Seventeen institutions were surveyed, and data on 131 patients were collected. These data were compared with updated data that were previously obtained for 466 patients treated during 1985-1994 and 142 patients treated during 1995-1999. Recent trends toward decrease in male/female ratio, increase in aged patients, and increase in patients with multiple lesions were seen. Regarding treatment, decrease in attempts at surgical tumor removal and increases in use of systemic chemotherapy and methotrexate (MTX)-containing regimens were observed. The median survival time was 18, 29, and 24 months for patients seen during 1985-1994, 1995-1999, and 2000-2004, respectively, and the respective 5-year survival rates were 15%, 30%, and 30%. In groups seen during 1995-1999 and during 2000-2004, patients who received systemic or MTX-containing chemotherapy had better prognosis than those who did not. Multivariate analysis of all patients seen during 1985-2004 suggested the usefulness of MTX-containing chemotherapy as well as the importance of age, lactate dehydrogenase level, and tumor multiplicity as prognostic factors. Thus, this study revealed several notable changes in clinical features of PCNSL patients. The prognosis improved during the last 10 years. Advantage of radiation plus chemotherapy, especially MTX-containing chemotherapy, over radiation alone was suggested.


Japanese Journal of Clinical Oncology | 2008

Variation of Clinical Target Volume Definition among Japanese Radiation Oncologists in External Beam Radiotherapy for Prostate Cancer

Katsumasa Nakamura; Yoshiyuki Shioyama; Sunao Tokumaru; Nobuyuki Hayashi; Natsuo Oya; Yoshiyuki Hiraki; Kazuo Kusuhara; Takafumi Toita; Hiroaki Suefuji; Naofumi Hayabuchi; Hiromi Terashima; Masaoki Makino; Kenichi Jingu

BACKGROUND We investigated the interobserver variation in the prostate target volume and the trend toward the use of diagnostic computed tomography (CT) or magnetic resonance (MR) images for treatment planning. METHODS Twenty-five radiation oncologists were asked to draw the external contour of the prostate on CT images (0.3 cm spacing) of a patient with localized prostate cancer. They also answered a questionnaire regarding the use of diagnostic CT or MR images for the contouring. RESULTS Of the 25 physicians, 28% rarely or never referred to the diagnostic CT images. In contrast, the physicians tended to refer to the MR images more frequently. Approximately 50% of the physicians believed in the usefulness of contrast-enhanced images for the delineation of the prostate. As for the variation of the prostate contouring, the median craniocaudal prostate length was 36 mm (range, 21-54 mm), and the median prostate volume was 43.5 cm(3) (range, 23.8-98.3 cm(3)). The interobserver variability was not significant in the duration as a radiation oncologist, the board certification status as radiation oncologists, and the number of treatment plans developed for prostate cancer during the last 1 year. CONCLUSION A wide variety of the definitions of the prostate was found among Japanese radiation oncologists.


International Journal of Radiation Oncology Biology Physics | 2012

Long-term Results of Carbon Ion Radiation Therapy for Locally Advanced or Unfavorably Located Choroidal Melanoma: Usefulness of CT-based 2-Port Orthogonal Therapy for Reducing the Incidence of Neovascular Glaucoma

Shingo Toyama; Hiroshi Tsuji; Nobutaka Mizoguchi; Takuma Nomiya; Tadashi Kamada; Sunao Tokumaru; Atsushi Mizota; Yoshitaka Ohnishi; Hirohiko Tsujii

PURPOSE To determine the long-term results of carbon ion radiation therapy (C-ion RT) in patients with choroidal melanoma, and to assess the usefulness of CT-based 2-port irradiation in reducing the risk of neovascular glaucoma (NVG). METHODS AND MATERIALS Between January 2001 and February 2012, a total of 116 patients with locally advanced or unfavorably located choroidal melanoma received CT-based C-ion RT. Of these patients, 114 were followed up for more than 6 months and their data analyzed. The numbers of T3 and T2 patients (International Union Against Cancer [UICC], 5th edition) were 106 and 8, respectively. The total dose of C-ion RT varied from 60 to 85 GyE, with each dose given in 5 fractions. Since October 2005, 2-port therapy (51 patients) has been used in an attempt to reduce the risk of NVG. A dose-volume histogram analysis was also performed in 106 patients. RESULTS The median follow-up was 4.6 years (range, 0.5-10.6 years). The 5-year overall survival, cause-specific survival, local control, distant metastasis-free survival, and eye retention rates were 80.4% (95% confidence interval 89.0%-71.8%), 82.2% (90.6%-73.8%), 92.8% (98.5%-87.1%), 72.1% (81.9%-62.3%), and 92.8% (98.1%-87.5%), respectively. The overall 5-year NVG incidence rate was 35.9% (25.9%-45.9%) and that of 1-port group and 2-port group were 41.6% (29.3%-54.0%) and 13.9% (3.2%-24.6%) with statistically significant difference (P<.001). The dose-volume histogram analysis showed that the average irradiated volume of the iris-ciliary body was significantly lower in the non-NVG group than in the NVG group at all dose levels, and significantly lower in the 2-port group than in the 1-port group at high dose levels. CONCLUSIONS The long-term results of C-ion RT for choroidal melanoma are satisfactory. CT-based 2-port C-ion RT can be used to reduce the high-dose irradiated volume of the iris-ciliary body and the resulting risk of NVG.


Pediatric Neurosurgery | 2006

Stereotactic Radiation Therapy with Chemotherapy in the Management of Recurrent Medulloblastomas

Masamitsu Abe; Sunao Tokumaru; Kazuo Tabuchi; Yoshihisa Kida; Masashi Takagi; Junichi Imamura

Medulloblastomas are highly lethal tumors when they recur. Very few patients survive with conventional treatment. This report documents the preliminary study results of a treatment for recurrent medulloblastomas consisting of stereotactic radiation therapy (SRT) with chemotherapy. Four patients had local recurrence without apparent metastases and 8 patients had metastases with or without local recurrence. Twelve patients with 18 lesions underwent SRT as a single session (n = 8) or in a hypofractionated manner (n = 10) using a gamma knife or modified linear accelerator. All patients then received systemic chemotherapy. Five patients were treated with one to two sequential courses of high-dose chemotherapy with peripheral blood stem cell transplantation. The reduction in tumor size after SRT was often remarkable. Fourteen of 18 lesions treated disappeared 1–6 months after SRT. Two of 4 patients who had local recurrences without apparent metastasis at the time of SRT are alive without evidence of disease 70 and 72 months after SRT, respectively. In contrast, all 8 patients with metastasis had new lesions either in the spinal canal or on the surface of the brain outside the target area of SRT. Median progression-free survival and overall survival from the time of SRT were 9 and 19 months, respectively. The Kaplan-Meier estimates of PFS and overall survival at 3 years were 17 and 25%, respectively. One patient had brainstem edema after SRT causing bulbar palsy and quadriparesis. One patient died of toxicity of chemotherapy. Our experience suggests that local recurrence can be controlled by SRT with chemotherapy but survival of patients with metastases can not be improved effectively by SRT in conjunction with aggressive chemotherapy.


Radiotherapy and Oncology | 2014

Factors influencing survival outcome for radiotherapy for biliary tract cancer: A multicenter retrospective study

Yasuo Yoshioka; Kazuhiko Ogawa; Hirobumi Oikawa; Hiroshi Onishi; Nobue Uchida; Toshiya Maebayashi; Naoto Kanesaka; Tetsuro Tamamoto; Hirofumi Asakura; Takashi Kosugi; Kazuo Hatano; Michio Yoshimura; Kazunari Yamada; Sunao Tokumaru; Kenji Sekiguchi; Masao Kobayashi; Toshinori Soejima; Fumiaki Isohashi; Kenji Nemoto; Yasumasa Nishimura

PURPOSE To seek for the possible factors influencing overall survival (OS) with radiotherapy (RT) for biliary tract cancer. MATERIALS AND METHODS Data were collected retrospectively from RT database of 31 institutions in Japan. All patients underwent at least external beam RT. The factors influencing OS were investigated. RESULTS Data of 498 patients were analyzed. Median OS of the 212 patients who underwent surgery was significantly better than that of the 286 patients without surgery (31 vs. 15 months, p<0.001). The OS for the R0 or R1 resection group was significantly longer than that for the R2 or non-surgery group, as well as for n0 compared to n1 (all p<0.001). Chemoradiotherapy (CRT), both sequential and concurrent, resulted in a better OS than RT alone for the n1 group (31 vs. 13 months, p<0.001), and marginally better for the R0/R1 group (p=0.065; p=0.054 for concurrent CRT). However, no such benefit was observed for the R2/non-surgical patients. Multivariate analysis identified performance status, clinical stage, and surgery as significant factors. CONCLUSION Surgery, especially R0/R1 resection, seemed as the gold standard for treatment of biliary tract cancer including RT, even in the highly heterogeneous population obtained from the multicenter retrospective study. The possibility was shown that CRT yielded better survival benefit especially for n1 patients. We recommend that future prospective trials include an arm of adjuvant CRT at least for n1 and possibly R0/R1 patients.


Journal of Radiation Research | 2016

Recommendations for high-risk clinical target volume definition with computed tomography for three-dimensional image-guided brachytherapy in cervical cancer patients

Tatsuya Ohno; Masaru Wakatsuki; Takafumi Toita; Yuko Kaneyasu; Ken Yoshida; Shingo Kato; Noriko Li; Sunao Tokumaru; Hitoshi Ikushima; Takashi Uno; Shin-ei Noda; Tomoko Kazumoto; Yoko Harima

Abstract Our purpose was to develop recommendations for contouring the computed tomography (CT)-based high-risk clinical target volume (CTVHR) for 3D image-guided brachytherapy (3D-IGBT) for cervical cancer. A 15-member Japanese Radiation Oncology Study Group (JROSG) committee with expertise in gynecological radiation oncology initiated guideline development for CT-based CTVHR (based on a comprehensive literature review as well as clinical experience) in July 2014. Extensive discussions occurred during four face-to-face meetings and frequent email communication until a consensus was reached. The CT-based CTVHR boundaries were defined by each anatomical plane (cranial–caudal, lateral, or anterior–posterior) with or without tumor progression beyond the uterine cervix at diagnosis. Since the availability of magnetic resonance imaging (MRI) with applicator insertion for 3D planning is currently limited, T2-weighted MRI obtained at diagnosis and just before brachytherapy without applicator insertion was used as a reference for accurately estimating the tumor size and topography. Furthermore, utilizing information from clinical examinations performed both at diagnosis and brachytherapy is strongly recommended. In conclusion, these recommendations will serve as a brachytherapy protocol to be used at institutions with limited availability of MRI for 3D treatment planning.


Journal of Radiation Research | 2015

Treatment outcomes of patients with FIGO Stage I/II uterine cervical cancer treated with definitive radiotherapy: a multi-institutional retrospective research study

Takuro Ariga; Takafumi Toita; Shingo Kato; Tomoko Kazumoto; Masaki Kubozono; Sunao Tokumaru; Hidehiro Eto; Tetsuo Nishimura; Yuzuru Niibe; Kensei Nakata; Yuko Kaneyasu; Takeshi Nonoshita; Takashi Uno; Tatsuya Ohno; H. Iwata; Yoko Harima; Hitoshi Wada; K. Yoshida; Hiromichi Gomi; Hodaka Numasaki; Teruki Teshima; Shogo Yamada; Takashi Nakano

The purpose of this study was to analyze the patterns of care and outcomes of patients with FIGO Stage I/II cervical cancer who underwent definitive radiotherapy (RT) at multiple Japanese institutions. The Japanese Radiation Oncology Study Group (JROSG) performed a questionnaire-based survey of their cervical cancer patients who were treated with definitive RT between January 2000 and December 2005. A total of 667 patients were entered in this study. Although half of the patients were considered suitable for definitive RT based on the clinical features of the tumor, about one-third of the patients were prescribed RT instead of surgery because of poor medical status. The RT schedule most frequently utilized was whole-pelvic field irradiation (WP) of 30 Gy/15 fractions followed by WP with midline block of 20 Gy/10 fractions, and high-dose-rate intracavitary brachytherapy (HDR-ICBT) of 24 Gy/4 fractions prescribed at point A. Chemotherapy was administered to 306 patients (46%). The most frequent regimen contained cisplatin (CDDP). The median follow-up time for all patients was 65 months (range, 2–135 months). The 5-year overall survival (OS), pelvic control (PC) and disease-free survival (DFS) rates for all patients were 78%, 90% and 69%, respectively. Tumor diameter and nodal status were significant prognostic indicators for OS, PC and DFS. Chemotherapy has potential for improving the OS and DFS of patients with bulky tumors, but not for non-bulky tumors. This study found that definitive RT for patients with Stage I/II cervical cancer achieved good survival outcomes.


Journal of Dermatology | 2014

Successful treatment of oral squamous cell carcinoma with intra‐arterial cisplatin and concurrent radiotherapy

Shinichi Koba; Noriyuki Misago; Reiko Shirai; Sunao Tokumaru; Tomoyuki Noguchi; Yutaka Narisawa

yellowish plaque. A 1.3-cm red nodule with a hemorrhagic crust and 0.4-cm black papule arose within the plaque. Complete excision of the entire plaque was performed, and histopathology revealed NS in association with three distinct lesions: syringocystadenoma papilliferum, sebaceoma and trichoblastoma (Fig. 1a). Case 2 was a 61-year-old Japanese man who had a 2-year history of rapid growth in a previously asymptomatic plaque on his scalp since birth. There was no family history of malignancy. A physical examination of the left side of the scalp revealed a 1.0 cm 9 3.0 cm brown, verrucous plaque. A 3.0cm red nodule and 0.8-cm black papule arose within the plaque. Complete excision of the entire plaque was performed, and histopathology revealed NS in association with three distinct lesions: trichoblastoma, trichoepithelioma and squamous cell carcinoma (Fig. 1b). We performed an immunohistochemical study to elucidate bKlotho expression in NS. A paraffin-embedded tissue section was immunostained with 1:1000 diluted anti-bKlotho antibody (Aviva Systems Biology, San Diego, CA, USA). bKlotho was expressed in the epidermis of the NS lesion as well as in the normal epidermis (Fig. 1c). It was expressed in skin appendages of the NS lesion; the sebaceous duct (Fig. 1d), sebaceous cells (Fig. 1d) and most of the ectopic apocrine gland (Fig. 1e). In contrast, bKlotho expression was suppressed in the secondary tumors of NS; syringocystadenoma papilliferum (Fig. 1f), trichoblastoma (Fig. 1g), trichoepithelioma (Fig. 1h), sebaceoma (Fig. 1i) and squamous cell carcinoma (Fig. 1j). bKlotho regulates the function of FGF19 by forming a complex with fibroblast growth factor receptor (FGFR)4 to suppress the expression of the CYP7A1 gene, which encodes the ratelimiting enzyme for bile acid synthesis in hepatocytes. Additionally, anti-tumorigenic effects of bKlotho in hepatocellular carcinoma was reported. Although bKlotho and FGFR4 are expressed in skin, to our knowledge, there has been no report about the expression of bKlotho in skin diseases. A recent study reported postzygotic HRAS or KRAS mutations that resulted in constitutive activation of Ras–Raf–MAPK and PI3K–Akt signaling pathways in NS and its secondary tumors. Because the interaction of bKlotho with FGFR4 suppresses Akt signaling and proliferation of tumor cells, it is possible that the reduction of bKlotho expression synergistically enhances the HRASor KRAS-related Akt signaling in the epidermis of NS developing secondary tumors. However, further studies are required to clarify the roles of bKlotho in skin diseases including secondary tumors arising in NS.


Japanese Journal of Clinical Oncology | 2014

Patterns of practice in the radiation therapy for bladder cancer: survey of the Japanese Radiation Oncology Study Group (JROSG).

Toshiya Maebayashi; Hitoshi Ishikawa; Atsunori Yorozu; Daisaku Yoshida; Hiroyuki Katoh; Kenji Nemoto; Shunichi Ishihara; S. Takemoto; Naoya Ishibashi; Sunao Tokumaru; Tetsuo Akimoto

OBJECTIVE To retrospectively analyze the clinical outcomes of radiation therapy with or without chemotherapy for bladder cancer in Japan. METHODS A questionnaire-based survey of patients with pathologically proven bladder cancer treated by definitive radiation therapy between 2002 and 2006 was conducted by the Japanese Radiation Oncology Study Group, and the clinical records of 159 patients were collected from 17 institutions. Concurrent intra-arterial chemoradiotherapy and concurrent systemic chemoradiotherapy were administered in 51 and 33 patients, respectively. RESULTS The 5-year overall survival and bladder preservation rates were 48 and 39%, respectively. Eighty-nine (56%) patients developed recurrence (bladder, 48; regional lymph nodes, 4; distant sites, 41). The results of multivariate analysis revealed that adoption of chemotherapy was the only significant prognostic factor for overall survival (relative risk = 0.615 [95% confidence interval: 0.439-0.862], P = 0.005). The type of chemotherapy administered did not significantly affect the local control or overall survival rates. The actuarial 5-year overall survival rates and bladder preservation in the radiation therapy combined with intra-arterial chemotherapy group were 64 and 58%, respectively, and the corresponding rates in the radiation therapy combined with systemic chemotherapy group were 67 and 42%, respectively. CONCLUSIONS The results of this survey revealed the current status of practice of radiation therapy for bladder cancer in Japan. A multi-institutional prospective study is needed based on the results of this study to determine the optimal radiotherapeutic approach, including the need for concurrent chemotherapy and the appropriate chemotherapy regimen for invasive bladder cancer.

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Takafumi Toita

University of the Ryukyus

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Masahiko Oguchi

Japanese Foundation for Cancer Research

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Shingo Kato

Saitama Medical University

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