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Yamazaki H.,Kyoto Prefectural University of Medicine | Nakamura S.,Kyoto Prefectural University of Medicine | Nishimura T.,Ujitakeda Hospital | Kodani N.,Kyoto Prefectural University of Medicine | And 7 more authors.
Anticancer Research | Year: 2013

Reirradiation is a challenging field in the treatment of recurrent brain metastases. Because of the elevated risk of radiation toxicity due to previous irradiation, only a limited dose is prescribed. To enhance radiosensitivity, in the present analysis six patients received hypofractionated stereotactic radiotherapy (hSRT) with daily oral administration of the hypoxic sensitizer AK-2123 (sanazole) for progressive brain metastases after previous radiotherapy. The patients received daily oral administration of 1.0 g/day sanazole up to 2 h before radiotherapy. Three partial and three stable responses were observed, with no sanazole-related toxicity, except for a case of mild nausea. Brain failure with subsequent death occurred in one patient. The other patients maintained good performance status until disease progression in other lesions. hSRT with a hypoxic radiation sensitizer appears to have the potential to enhance the efficacy of radiotherapy. Source


Aibe N.,Kyoto Prefectural University of Medicine | Yamazaki H.,Kyoto Prefectural University of Medicine | Nakamura S.,Kyoto Prefectural University of Medicine | Tsubokura T.,Kyoto Prefectural University of Medicine | And 5 more authors.
Journal of Radiation Research | Year: 2014

To analyze outcomes and toxicities of stereotactic body radiotherapy with helical tomotherapy (HT-SBRT) for inoperable lung tumors, the medical records of 30 patients with 31 lung tumors treated with HT-SBRT were reviewed. The 3-year local control, cause-specific survival and overall survival rates (LC, CCS and OS, respectively) were analyzed using the Kaplan-Meier method. Toxicities were graded using Common Terminology Criteria for Adverse Events ver. 4. To investigate the factors associated with Grade 5 radiation pneumonitis (G5 RP), several parameters were analyzed: (i) patient-specific factors (age, gross tumor volume and PTV, and the interstitial pulmonary shadow on pretreatment CT); and (ii) dosimetry-specific factors (conformity index, homogeneity index, mean lung dose, and V5, V10, V15, V20 and V25 of the total lungs). The median duration of observation for all patients was 36.5 months (range, 4-67 months). The 3-year LC, CCS and OS were 82, 84 and 77%, respectively. Regarding Grade 3 or higher toxicities, two patients (6.7%) developed G5 RP. GTV was significantly associated with G5 RP (P = 0.025), and there were non-significant but slight associations with developing G5 RP for V5 (P = 0.067) and PTV (P = 0.096). HT-SBRT led to standard values of LC, CCS and OS, but also caused a markedly higher incidence of G5 RP. It is essential to optimize patient selection so as to avoid severe radiation pneumonitis in HT-SBRT. © 2014 The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology. Source


Nishimura T.,Ujitakeda Hospital | Yamazaki H.,Kyoto Prefectural University of Medicine | Aibe N.,Kyoto Prefectural University of Medicine | Nakamura S.,Kyoto Prefectural University of Medicine | And 2 more authors.
Anticancer Research | Year: 2013

Aim: To evaluate the incidence of rectal toxicity in patients undergoing hypofractionated (2.2 Gy) image-guided intensity-modulated radiotherapy (IG-IMRT) for prostate cancer. Patients and Methods: We examined 117 consecutive patients with prostate cancer who underwent IG-IMRT from June 2007 to July 2009. The median follow-up time was 32 months (range 20-42 months). The clinical target volume (CTV) consisted of the prostate and seminal vesicles, and the planning target volume (PTV) consisted of the CTV plus a 5-mm expansion, not avoiding the rectum. The PTV received a dose of 72.6-74.8 Gy in 33-34 fractions (2.2 Gy/fraction). Megavoltage computed tomographic (MVCT) scans were performed before each treatment and corrected to the registered position for planning CT scans using prostate soft tissue matching. Results: Late rectal bleeding of grades 1, 2, and 3 (Common Terminology Criteria for Adverse Events v3.0) occurred in 19 (16%), five (4%), and four (3%) patients, respectively. Late urinary toxicities of grades 1 and 2 occurred in five (4.3%) and eight (6.8%) patients, respectively. We found a paradoxically increased risk of rectal bleeding with more accurate irradiation of the rectum using soft tissue matching, whereas only a small percentage was reported in other IMRT series. Conclusion: IG-IMRT using daily MVCT scans allowed for exact dose delivery, which resulted in an increased rectal dose and exceptionally high incidence of rectal toxicity. Therefore, careful PTV contouring and dose schedule settings are important for safe administration of IG-IMRT. Source


Yamazaki H.,Kyoto Prefectural University of Medicine | Nakamura S.,Kyoto Prefectural University of Medicine | Nishimura T.,Ujitakeda Hospital | Okabe H.,Ujitakeda Hospital | And 3 more authors.
Anticancer Research | Year: 2013

Background: Glioblastoma has a very poor prognosis even after incorporation into therapy of the newly-developed drug, temozolomide. Case Report: We present a case of 62-year-old woman with glioblastoma multiforme treated with tomotherapy intensity-modulated radiation therapy using simultaneous integrated boost technique (SIB-IMRT) along with a daily oral dose of a hypoxic radiation sensitizer, sanazole (AK-2123). SIB-IMRT was administered at a dose of 60 Gy in 20 fractions for high-risk planning target volume (PTV) and at 40 Gy for low-risk PTV. The patient received an oral administration of sanazole (1.0 g/day) for 10 days, 2 h before radiotherapy. She achieved a complete response without any adverse events, and remained disease-free for 3.5 years. Our study demonstrates that the higher single-dose radiotherapy combined with a hypoxic radiation sensitizer has the potential to enhance the efficacy of radiotherapy. Source


Nishimura T.,Ujitakeda Hospital | Yamazaki H.,Ujitakeda Hospital | Yamazaki H.,Kyoto Prefectural University of Medicine | Iwama K.,Ujitakeda Hospital | And 8 more authors.
Journal of Medical Case Reports | Year: 2014

Introduction. Radiotherapy is a standard treatment for prostate cancer, and image-guided radiotherapy is increasingly being used to aid precision of dose delivery to targeted tissues. However, precision during radiotherapy cannot be maintained when unexpected intrafraction organ motion occurs. Case presentation. We report our experience of internal organ motion caused by persistent gas production in a patient taking an alpha-glucosidase inhibitor. A 68-year-old Japanese man with prostate cancer visited our institution for treatment with helical tomotherapy. He suffered from diabetes mellitus and took an alpha-glucosidase inhibitor. Routine treatment planning computed tomography showed a large volume of rectal gas; an enema was given to void the rectum. Subsequent treatment planning computed tomography again showed a large volume of gas. After exercise (walking) to remove the intestinal gas, a third scan was performed as a test scan without tight fixation, which showed a sufficiently empty rectum for planning. However, after only a few minutes, treatment planning computed tomography again showed extreme accumulation of gas. Therefore, we postponed treatment planning computed tomography and consulted his doctor to suspend the alpha-glucosidase inhibitor, which was the expected cause of his persistent gas. Four days after the alpha-glucosidase inhibitor regimen was suspended, we took a fourth treatment planning computed tomography and made a treatment plan without gas accumulation. Thereafter, the absence of rectal gas accumulation was confirmed using daily megavolt computed tomography before treatment, and the patient received 37 fractions of intensity-modified radiotherapy at 74Gy without rectal gas complications. In this case study, the alpha-glucosidase inhibitor induced the accumulation of intestinal gas, which may have caused unexpected organ motion, untoward reactions, and insufficient doses to clinical targets. Conclusions: We suggest that patients who are taking an alpha-glucosidase inhibitor for diabetes should discontinue use of that particular medicine prior to beginning radiotherapy. © 2014 Nishimura et al.; licensee BioMed Central Ltd. Source

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