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Dive into the research topics where Hideomi Yamashita is active.

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Featured researches published by Hideomi Yamashita.


Radiation Oncology | 2007

Exceptionally high incidence of symptomatic grade 2-5 radiation pneumonitis after stereotactic radiation therapy for lung tumors.

Hideomi Yamashita; Keiichi Nakagawa; Naoki Nakamura; Hiroki Koyanagi; Masao Tago; Hiroshi Igaki; Kenshiro Shiraishi; Nakashi Sasano; Kuni Ohtomo

BackgroundTo determine the usefulness of dose volume histogram (DVH) factors for predicting the occurrence of radiation pneumonitis (RP) after application of stereotactic radiation therapy (SRT) for lung tumors, DVH factors were measured before irradiation.MethodsFrom May 2004 to April 2006, 25 patients were treated with SRT at the University of Tokyo Hospital. Eighteen patients had primary lung cancer and seven had metastatic lung cancer. SRT was given in 6–7 fields with an isocenter dose of 48 Gy in four fractions over 5–8 days by linear accelerator.ResultsSeven of the 25 patients suffered from RP of symptomatic grade 2–5 according to the NCI-CTC version 3.0. The overall incidence rate of RP grade2 or more was 29% at 18 months after completing SRT and three patients died from RP. RP occurred at significantly increased frequencies in patients with higher conformity index (CI) (p = 0.0394). Mean lung dose (MLD) showed a significant correlation with V5–V20 (irradiated lung volume) (p < 0.001) but showed no correlation with CI. RP did not statistically correlate with MLD. MLD had the strongest correlation with V5.ConclusionEven in SRT, when large volumes of lung parenchyma are irradiated to such high doses as the minimum dose within planning target volume, the incidence of lung toxicity can become high.


Journal of Medical Case Reports | 2011

Abscopal effect of radiation on lung metastases of hepatocellular carcinoma: a case report.

Kae Okuma; Hideomi Yamashita; Yuzuru Niibe; Kazushige Hayakawa; Keiichi Nakagawa

IntroductionThe abscopal effect is the effect of radiation therapy at a site distant to the area of irradiation. This is not a common event and has not been clearly defined, resulting in few reported cases in the literature. We discuss this phenomenon in a patient with hepatocellular carcinoma.Case presentationA 63-year-old Japanese man underwent extended right hepatic lobectomy for hepatocellular carcinoma. During his follow-up examination, a single lung metastasis and a single mediastinal lymph node metastasis were found. Trans-catheter arterial embolization was initially attempted to treat the mediastinal tumor, however this approach failed to take effect and carried risks of spinal artery embolism. External-beam irradiation, with a dose of 2.25 Gy per fraction, was performed using an antero-posterior parallel-opposed technique (total dose, 60.75 Gy). A computed tomography scan performed one month after starting radiotherapy showed a remarkable reduction of the mediastinal lymph node metastasis. In addition to this, we observed spontaneous shrinking of the lung metastasis, which was located in the right lower lobe and out of the radiation field. No chemotherapy was given during the period. There has been no recurrence of either the lung metastasis or the mediastinal lymph node metastasis during a follow-up 10 years after the radiotherapy.ConclusionWe observed a rare abscopal effect in a site distant from the area of irradiation. Irradiation of the mediastinum resulted in tumor mass regression in the untreated lung tumor.


Radiation Oncology | 2010

Prescreening based on the presence of CT-scan abnormalities and biomarkers (KL-6 and SP-D) may reduce severe radiation pneumonitis after stereotactic radiotherapy

Hideomi Yamashita; Shino Kobayashi-Shibata; Atsuro Terahara; Kae Okuma; Akihiro Haga; Reiko Wakui; Kuni Ohtomo; Keiichi Nakagawa

PurposeTo determine the risk factors of severe radiation pneumonitis (RP) after stereotactic body radiation therapy (SBRT) for primary or secondary lung tumors.Materials and methodsFrom January 2003 to March 2009, SBRT was performed on 117 patients (32 patients before 2005 and 85 patients after 2006) with lung tumors (primary = 74 patients and metastatic/recurrent = 43 patients) in our institution. In the current study, the results on cases with severe RP (grades 4-5) were evaluated. Serum Krebs von den Lungen-6 (KL-6) and serum Surfactant protein-D (SP-D) were used to predict the incidence of RP. A shadow of interstitial pneumonitis (IP) on the CT image before performing SBRT was also used as an indicator for RP. Since 2006, patients have been prescreened for biological markers (KL-6 & SP-D) as well as checking for an IP-shadow in CT.ResultsGrades 4-5 RP was observed in nine patients (7.7%) after SBRT and seven of these cases (6.0%) were grade 5 in our institution. A correlation was found between the incidence of RP and higher serum KL-6 & SP-D levels. IP-shadow in patients CT was also found to correlate well with the severe RP. Severe RP was reduced from 18.8% before 2005 to 3.5% after 2006 (p = 0.042). There was no correlation between the dose volume histogram parameters and these severe RP patients.ConclusionPatients presenting with an IP shadow in the CT and a high value of the serum KL-6 & SP-D before SBRT treatment developed severe radiation pneumonitis at a high rate. The reduction of RP incidence in patients treated after 2006 may have been attributed to prescreening of the patients. Therefore, pre-screening before SBRT for an IP shadow in CT and serum KL-6 & SP-D is recommended in the management and treatment of patients with primary or secondary lung tumors.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2006

Taste dysfunction in patients receiving radiotherapy.

Hideomi Yamashita; Keiichi Nakagawa; Masao Tago; Naoki Nakamura; Kenshiro Shiraishi; Momoe Eda; Hiroki Nakata; Nami Nagamatsu; Rika Yokoyama; Mayuko Onimura; Kuni Ohtomo

Taste loss is a major cause of morbidity in patients undergoing head and neck irradiation.


International Journal of Radiation Oncology Biology Physics | 2011

Four-Dimensional Measurement of the Displacement of Internal Fiducial Markers During 320-Multislice Computed Tomography Scanning of Thoracic Esophageal Cancer

Hideomi Yamashita; Satoshi Kida; A. Sakumi; Akihiro Haga; Saori Ito; Tsuyoshi Onoe; Kae Okuma; Kenji Ino; Masaaki Akahane; Kuni Ohtomo; Keiichi Nakagawa

PURPOSE To investigate the three-dimensional movement of internal fiducial markers placed near esophageal cancers using 320-multislice CT. METHODS AND MATERIALS This study examined 22 metal markers in the esophageal wall near the primary tumors of 12 patients treated with external-beam photon radiotherapy. Motion assessment was analyzed in 41 respiratory phases during 20 s of cine CT in the radiotherapy position. RESULTS Motion in the cranial-caudal (CC) direction showed a strong correlation (R(2) > 0.4) with the respiratory curve in most markers (73%). The average absolute amplitude of the marker movement was 1.5 ± 1.6 mm, 1.6 ± 1.7 mm, and 3.3 ± 3.3 mm in the left-right (LR), anterior-posterior (AP), and CC directions, respectively. The average marker displacements in the CC direction between peak exhalation and inhalation for the 22 clips were 1.1 mm (maximum, 5.5 mm), 3.0 mm (14.5 mm), and 5.1 mm (16.3 mm) for the upper, middle, and lower thoracic esophagus, respectively. CONCLUSIONS Motion in primary esophagus tumor was evaluated with 320-multislice CT. According to this study, 4.3 mm CC, 1.5 mm AP, and 2.0 mm LR in the upper, 7.4 mm CC, 3.0 mm AP, and 2.4 mm LR in the middle, and 13.8 mm CC, 6.6 mm AP, and 6.8 mm LR in the lower thoracic esophagus provided coverage of tumor motion in 95% of the cases in our study population.


Acta Oncologica | 2009

Quality assurance of volumetric modulated arc therapy using Elekta Synergy

Akihiro Haga; Keiichi Nakagawa; Kenshiro Shiraishi; S Itoh; Atsuro Terahara; Hideomi Yamashita; Kuni Ohtomo; Shigeki Saegusa; Toshikazu Imae; Kiyoshi Yoda; Roberto Pellegrini

Purpose. Recently, Elekta has supplied volumetric modulated arc therapy (VMAT) in which multi-leaf collimator (MLC) shape, jaw position, collimator angle, and gantry speed vary continuously during gantry rotation. A quality assurance procedure for VMAT delivery is described. Methods and materials. A single-arc VMAT plan with 73 control points (CPs) and 5-degree gantry angle spacing for a prostate cancer patient has been created by ERGO + + treatment planning system (TPS), where MLC shapes are given by anatomic relationship between a target and organs at risk and the monitor unit for each CP is optimized based on given dose prescriptions. Actual leaf and jaw positions, gantry angles and dose rates during prostate VMAT delivery were recorded in every 0.25 seconds, and the errors between planned and actual values were evaluated. The dose re-calculation using these recorded data has been performed and compared with the original TPS plan using the gamma index. Results. Typical peak errors of gantry angles, leaf positions, and jaw positions were 3 degrees, 0.6 mm, and 1 mm, respectively. The dose distribution obtained by the TPS plan and the recalculated one agreed well under 2%-2 mm gamma index criteria. Conclusions. Quality assurance for prostate VMAT delivery has been performed with a satisfied result.


Journal of Radiation Research | 2015

Survival outcomes after stereotactic body radiotherapy for 79 Japanese patients with hepatocellular carcinoma

Hideomi Yamashita; Hiroshi Onishi; Naoya Murakami; Yasuo Matsumoto; Yukinori Matsuo; Takuma Nomiya; Keiichi Nakagawa

Stereotactic body radiotherapy (SBRT) is a relatively new treatment for liver tumor. Outcomes of SBRT for liver tumors unsuitable for ablation or surgical resection were evaluated. A total of 79 patients treated with SBRT for primary hepatocellular carcinoma (HCC) between 2004 and 2012 in six Japanese institutions were studied retrospectively. Patients treated with SBRT preceded by trans-arterial chemoembolization were eligible. Their median age was 73 years, 76% were males, and their Child–Pugh scores were Grades A (85%) and B (11%) before SBRT. The median biologically effective dose (α/β = 10 Gy) was 96.3 Gy. The median follow-up time was 21.0 months for surviving patients. The 2-year overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival were 53%, 40% and 76%, respectively. Sex and serum PIVKA-II values were significant predictive factors for OS. Hypovascular or hypervascular types of HCC, sex and clinical stage were significant predictive factors for PFS. The 2-year PFS was 66% in Stage I vs 18% in Stages II–III. Multivariate analysis indicated that clinical stage was the only significant predictive factor for PFS. No Grade 3 laboratory toxicities in the acute, sub-acute, and chronic phases were observed. PFS after SBRT for liver tumor was satisfactory, especially for Stage I HCC, even though these patients were unsuitable for resection and ablation. SBRT is safe and might be an alternative to resection and ablation.


Radiotherapy and Oncology | 2008

Radiotherapy for 41 patients with stages I and II MALT lymphoma: A retrospective study

Hideomi Yamashita; Keiichi Nakagawa; Takao Asari; Naoya Murakami; Hiroshi Igaki; Kuni Ohtomo

PURPOSE Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct disease with specific clinical and pathologic features that may affect diverse organs. We analyzed our recent experience with Stage I/II MALT lymphoma presenting in the stomach and other organs to assess the outcome following radiation therapy (RT) alone. PATIENTS AND METHODS Forty-one patients with Stages I (37) and II (4) disease were treated between 2000 and 2006. Patients with transformed MALT were excluded. The median age was 60 years (range, 25-86 years), male: female ratio 1:1. Presenting sites included stomach, 11; orbital adnexa, 21; thyroid, 1; other head and neck, 3; small bowel, 3; skin, 1; and rectum, 1. Thirty-five patients (85%) received RT-alone and 6 (15%) received antibiotics followed by RT. RT dose was 30Gy in 20 fractions (fr) in all 41 patients. Mean follow-up time was 32.0 months (range, 2.1-162 months). RESULTS A first complete response was achieved in all 41 patients. Only one patient died from bile duct carcinoma at 22 months from the start of irradiation for conjunctiva MALT lymphoma without recurrence of lymphoma. The other 40 patients were alive. Thirty-eight patients out of them were alive without recurrence. One patient with a duodenal lymphoma had a recurrence in non-irradiated distant sites at 1 month. Another patient with a bilateral eye lid lymphoma had a recurrence within radiation field at 41 months. The absolute local control rate with radiation was 98% (40/41 patients). CONCLUSION Localized MALT lymphomas have excellent prognosis following moderate-dose RT (30Gy/20fr).


Radiotherapy and Oncology | 2011

Details of recurrence sites after elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT) combined with chemotherapy for thoracic esophageal squamous cell carcinoma--a retrospective analysis.

Hideomi Yamashita; Kae Okuma; Reiko Wakui; Shino Kobayashi-Shibata; Kuni Ohtomo; Keiichi Nakagawa

PURPOSE To describe patterns of recurrence of elective nodal irradiation (ENI) in definitive chemoradiotherapy (CRT) for thoracic esophageal squamous cell carcinoma (SqCC) using 3D-conformal radiotherapy. METHODS AND MATERIALS One hundred and twenty-six consecutive patients with stages I-IVB thoracic esophageal SqCC newly diagnosed between June 2000 and July 2009 and treated with 3D-CRT in our institution were recruited from our database. Definitive CRT consisted of two cycles of nedaplatin/5FU repeated every 4 weeks, with concurrent radiation therapy of 50-50.4 Gy in 25-28 fractions. Until completion, radiotherapy was delivered to the N1 and M1a lymph nodes as ENI in addition to gross tumor volume. RESULTS All 126 patients were included in this analysis, and their tumors were staged as follows: T1/T2/T3/T4, 28/18/54/26; N0/N1, 50/76; M0/M1a/M1b, 91/5/30. The mean follow-up period for the 63 surviving patients was 28.3 (±22.8) months. Eighty-seven patients (69%) achieved complete response (CR) without any residual tumor at least once after completion of CRT. After achieving CR, each of 40 patients experienced failures (local=20 and distant=20) and no patient experienced elective nodal failure without having any other site of recurrence. The upper thoracic esophageal carcinoma showed significantly more (34%) relapses at the local site than the middle (9%) or lower thoracic (11%) carcinomas. The 2-year and 3-year overall survival was 56% and 43%, respectively. The 1-year, 2-year and 3-year disease-free survival was 46%, 38% and 33%, respectively. CONCLUSIONS In CRT for esophageal SqCC, ENI was effective for preventing regional nodal failure. The upper thoracic esophageal carcinomas had significantly more local recurrences than the middle or lower thoracic sites.


Oral Oncology | 2009

Umami taste dysfunction in patients receiving radiotherapy for head and neck cancer

Hideomi Yamashita; Keiichi Nakagawa; Yoshio Hosoi; Azusa Kurokawa; Yusuke Fukuda; Ichiro Matsumoto; Takumi Misaka; Keiko Abe

Taste loss is a major cause of morbidity in patients undergoing head and neck irradiation. Previous studies have reported the alteration of the four basic tastes in patients with head and neck cancer during radiotherapy. However, only a few studies have been conducted on the effects of irradiation on the function of umami taste, a novel and basic taste recently recognized. In a prospective study, 52 patients undergoing radical head and neck irradiation were assessed for taste loss. Taste ability was measured by the taste threshold for umami quality using the whole-mouth taste method in patients before, during, and immediately after radiotherapy. Umami taste declined of the 3rd week after the start of radiotherapy and improved of the 8th week.

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