Keiji Hayashi
Tokyo Medical and Dental University
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Featured researches published by Keiji Hayashi.
International Journal of Radiation Oncology Biology Physics | 2009
Ryo-ichi Yoshimura; Hitoshi Shibuya; Masahiko Miura; Hiroshi Watanabe; Fumio Ayukawa; Keiji Hayashi; Kazuma Toda
PURPOSE To assess the quality of life (QOL) of oral cancer patients treated with low-dose-rate interstitial brachytherapy (LDR-BT) alone. METHODS AND MATERIALS Between June 2005 and July 2006, a total of 56 patients with oral cancer were enrolled in this prospective study. QOL was assessed by means of the core questionnaire and head and neck questionnaire module of the European Organization for Research and Treatment of Cancer (EORTC Quality of Life Questionnaire-Core 30 [QLQ-C30] and QLQ Head and Neck 35 [H&N35]). The questionnaires were distributed to the patients before the start of treatment and 3 months, 6 months, and 12 months after the start of LDR-BT. RESULTS It was possible to analyze the results for 20 of the initial 56 patients because they did not experience metastasis or recurrence during this study. No functions or symptoms asked about in the QLQ-C30 deteriorated during the first year. The emotional function score steadily and significantly increased. No symptoms in the QLQ-H&N35 significantly deteriorated. The scores for pain, trouble with social eating, and weight loss on the QLQ-H&N35 steadily and significantly decreased. Age, gender, and LDR-BT source had no effect on the change in QOL during the first year, but T-stage significantly affected the change in global health status, tumor site affected the changes in swallowing, sensory problems, sticky saliva, and complications affected the changes in pain, swallowing, and mouth opening. CONCLUSIONS QOL of oral cancer patients treated with LDR-BT is high. However, tumor stage, tumor site, and complications affected the changes in a few functions and symptoms during the first year.
Digestive Diseases and Sciences | 2007
Mikio Tezuka; Keiji Hayashi; Kazunori Kubota; Sachiko Sekine; Yoichi Okada; Hiroyasu Ina; Tetsuya Irie
We compared the growth rate of locally recurrent hepatocellular carcinoma (HCC) with that of primary HCC. After the first treatment by transcatheter arterial chemoembolization (TACE), 60 locally recurrent HCC nodules were reviewed. The tumor volume doubling time (DT) of locally recurrent HCC was significantly shorter than that of primary HCC. The 95% lower threshold value was 17.7 days. The 6-, 12-, and 36-month recurrence-free rates of the tumors having DTs more than 70 days after the second TACE (77.7%, 53.8%, and 40.4%) were significantly higher than those of the tumors having DTs less than 70 days (26.7%, 26.7%, and 17.8%). Locally recurrent HCCs cannot double in diameter in less than 53 days. In the case that an equivocal lesion smaller than the section collimation depicted during a contrast-enhanced computed tomography (CECT) screening cannot be ruled out as local recurrence, the next CECT screening should be performed 2 months later.
CardioVascular and Interventional Radiology | 2007
Keiji Hayashi; Hiroyasu Ina; Mikio Tezuka; Yoichi Okada; Tetsuya Irie
PurposeTo elucidate the local therapeutic results of computed tomography (CT)-guided transcatheter arterial chemoembolization (TACE) as initial treatment for hepatocellular carcinoma (HCC), and to verify factors which affect local therapeutic results.MethodsFrom 1992 to 2002, 265 tumors of 79 HCC patients were treated by 139 sessions of CT-guided TACE as initial treatment. Among these 265 tumors, 182 constituted multiple new lesions, and the remaining 83 tumors were single new lesions. Local recurrence was retrospectively ascertained on follow-up CT images obtained after TACE.ResultsThe overall local recurrence-free rates (LR-FRs) after a single TACE session at 6, 12, and 36 months were 67%, 49%, and 28%; those of the single new lesions were 80%, 66%, and 32%; and those of tumors with complete lipiodol accumulation were 82%, 68%, and 41%, respectively. LR-FRs of tumors of the single new lesions, and those of tumors with complete lipiodol accumulation, were significantly higher than the LR-FRs of multiple new lesions and tumors with incomplete lipiodol accumulation, respectively. For single new lesions ≤4 cm and the tumors that were one of multiple new lesions, there were no significant differences in the LR-FRs regarding the number of TACE sessions on the basis of patient, tumor location, or tumor size.ConclusionLocal therapeutic results of single new lesions were better than those of multiple new lesions, and the local therapeutic effect of TACE was not affected by the number of treatments on the basis of patient, tumor location, or tumor size.
Journal of Radiation Research | 2012
Satoko Hayashi; Keiji Hayashi; Ryo-ichi Yoshimura; Hitoshi Masuda; Kazunori Kihara; Hitoshi Shibuya
External beam radiotherapy is a potential salvage or adjuvant therapy after radical prostatectomy (RP). The purpose of this study was to investigate the treatment outcome of salvage radiotherapy (RT) following RP for clinically localized prostate cancer and to identify factors that may predict the outcome of salvage RT. Between 2000 and 2006, 41 patients received salvage RT because of increasing prostate-specific antigen (PSA) levels following an RP for clinically localized prostate cancer. All the patients received conformal radiotherapy to the prostate bed. The prescribed radiation dose was 60–70 Gy in 26–35 fractions. The overall 5-year biochemical disease-free survival rate was 38%. A multivariate analysis showed that the following pathological findings of the surgical specimen were significantly associated with biochemical failure following salvage RT: a high Gleason score, a negative surgical margin, seminal vesicle invasion, lymphatic vessel invasion and negative vascular invasion. Among these factors, lymphatic vessel invasion was the strongest predictor. In conclusion, the pathological features affected the outcome of salvage RT following RP. Lymphatic vessel invasion was strongly associated with the risk of biochemical failure despite salvage RT. Meanwhile, vascular invasion was not a significant hazardous factor.
Digestive Diseases and Sciences | 2009
Mikio Tezuka; Keiji Hayashi; Yoichi Okada; Tetsuya Irie; Hiroyasu Ina
The aim of this study was to retrospectively evaluate the long-term results of transcatheter arterial chemoembolization (TACE) for the treatment of local recurrence of hepatocellular carcinoma (HCC) after the first TACE. Between September 1992 and October 2004, 85 recurrent HCC nodules of 35 patients were treated by TACE. During the median follow-up period of 15.5 months (range 1.9–58.6 months), 58 of the 85 treated tumors developed local recurrence again after the second TACE. The overall 6-, 12-, and 36-month recurrence-free rates of these tumors after the second TACE were 47.0%, 36.2%, and 25.8%, respectively. Local recurrence of HCC after the first TACE was treated by a second TACE with equivalent efficacy as that of the initial TACE, if segmental chemoembolization was achieved. We regard TACE as the treatment of choice for the management of local recurrence of HCC.
Radiation Oncology | 2009
Kazuma Toda; Hitoshi Shibuya; Keiji Hayashi; Fumio Ayukawa
Backgroundsurvivors of non-Hodgkins lymphoma (NHL) are well known to be at an increased risk of second malignancies. In this study, we evaluated the incidence and clinical features of head and neck cancer (HNC) occurring after radiotherapy (RT) for NHL.Materials and methodsWe investigated the clinical records of 322 patients who had received RT for early-stage NHL of the head and neck at our institute between 1952 and 2000.ResultsThere were 4 patients with a second HNC developing in the irradiated field, consisting of 2 patients with gum cancer, 1 case with tongue cancer and 1 case with maxillary sinus cancer. The pathological diagnosis in all the 4 patients was squamous cell carcinoma (SCC). Two of the patients (one with gum cancer and one with maxillary sinus cancer) died of the second HNC, while the remaining 2 patients are still living at the time of writing after therapy for the second HNC, with neither recurrence of the second tumor nor relapse of the primary tumor. The ratio of the observed to the expected number (O/E ratio) of a second HNC was calculated to be 12.7 (95%CI, 4.07–35.0), and the absolute excess risk (AER) per 10,000 person-years was 13.3. The median interval between the RT and the diagnosis of the second HNC was 17.0 years (range, 8.7 to 22.7 years).ConlusionThe risk of HNC significantly increased after RT for early-stage NHL. These results suggest that second HNC can be regarded as one of the late complications of RT for NHL of the head and neck.
Brachytherapy | 2008
Ryo-ichi Yoshimura; Keiji Hayashi; Fumio Ayukawa; Kazuma Toda; Masaru Iwata; Sayako Oota; Akihiko Hoshi; Masaru Wakatsuki; Hiromasa Kurosaki; Atsushi Okazaki; Hitoshi Shibuya
PURPOSE The authors analyzed the correlation between radiotherapy doses at reference points on the uterine edge and the rectal wall and both pelvic control and late rectal complications of cervical cancer therapy. METHODS AND MATERIALS Between 1997 and 2005, 57 patients with Stages IB-IVA cancer of uterine cervix were treated with a combination of external beam radiotherapy and high-dose-rate intracavitary brachytherapy. Their high-dose-rate intracavitary brachytherapy was planned by dose-point optimization at six dose points located on the edge of uterus by computed tomography. A rectal reference point located on the anterior wall of the rectum by computed tomography was also used. The pelvic control rate and the rate of late rectal complications were calculated according to the biologically effective dose (BED) at each point and several clinical parameters. RESULTS The overall 3-year pelvic control rate was 69.4%. The patients with a BED >80 Gy10 at the point on the edge of the uterine cervix had better pelvic control (78.4% at 3 years) than the patients with a BED < or =80 Gy10 (54.4% at 3 years), and the difference was significant. The difference in the BED (Gy3) at the rectal reference point between the patients with Grade 0-1 late rectal complications (median, 114 Gy) and the patients who developed Grade > or =2 late rectal complications (median, 178 Gy) was significant. Chemotherapy was a borderline significant parameter in regard to correlation with pelvic control and late rectal complications, but there were no correlations with other dosimetric or clinical parameters. CONCLUSIONS The radiotherapy dose at the reference point on the edge of the cervix affected pelvic control more than the clinical parameters, and the dose at the rectal reference point was more strongly correlated with the occurrence of late rectal complications.
International Journal of Radiation Oncology Biology Physics | 2012
Ryo-ichi Yoshimura; Hitoshi Shibuya; Keiji Hayashi; K. Nakagawa; Kazuma Toda; Hiroshi Watanabe; A. Kaida; Masahiko Miura
PURPOSE To analyze data from patients receiving repeat brachytherapy (re-BT) for the treatment of residual or recurrent tumor in the oral cavity. METHODS AND MATERIALS Between January 2003 and December 2007, 62 patients who had undergone definitive BT as an initial treatment of oral cancer subsequently underwent re-BT for the treatment of residual or recurrent tumors at the diagnostic radiology and oncology department (Tokyo Medical and Dental University Hospital). Re-BT was performed 0.9-73 months (median, 5.7) after the initial BT. Au-198 grains were used as the re-BT source in all 62 patients, and an area of 0.8-6.3 cm(2) (median, 3.1) was permanently irradiated with 60-110 Gy (median, 83) according to the system of Paterson-Parker. RESULTS The 2-year local control and overall survival rate was 53% and 66%, respectively, and local control significantly affected overall survival. Both local control and overall survival were affected by the initial tumor characteristics and the macroscopic appearance of the residual or recurrent tumor. Grade 3 or 4 complications were seen in 5 patients. The incidence of mandibular and mucosal complications was significantly related to a biologic effective dose of α/β of 3 Gy to the surface of the gingiva and mucosa, respectively. CONCLUSION Re-BT using Au-198 grains for the treatment of residual or recurrent tumor after definitive BT in the oral cavity is effective and well tolerated.
Ophthalmologica | 2009
Keiji Hayashi; Kunito Hatsuno; Ryo-ichi Yoshimura; Toshiaki Iida; Fumio Ayukawa; Kazuma Toda; Hisashi Taniguchi; Hitoshi Shibuya
Purpose: To establish the protective efficacy against late complications of electron therapy using customized lead eye shields in cases with orbital and periorbital lesions. Methods: Between 1982 and 2006, 16 patients with 22 orbital and periorbital lesions were treated by electron therapy. Customized lead eye shields were prepared and placed in the respective patients’ eyes during each fraction of electron therapy. The toxicity and local control rates were analyzed. Results: The preparation period for the customized lead eye shields was 2 days. The shields could be used throughout the treatment period in all the patients. No evidence of radiation cataract was observed in 15 of the 16 patients. None of the patients developed corneal ulceration or evidence of lead poisoning. Conclusion: Customized lead eye shields could be made relatively quickly, and electron therapy for orbital and periorbital lesions could be undertaken safely without any late complication.
Journal of Radiation Research | 2013
Yoshiharu Ryu; Hitoshi Shibuya; Keiji Hayashi
Brachytherapy using 198Au grains is minimally invasive and the only curative treatment for early tongue cancer in patients of advanced age or poor performance status available in our institution. From March 1993 to February 2008, 198Au grains were used to treat a group of 96 Stage I–II tongue cancer patients who could not undergo surgery or brachytherapy using 192Ir pins because of an advanced age (≥75 years) or poor performance status (≥2). The patients were followed for 3.9 ± 3.3 years, and the cause-specific survival and local control rates were determined. Survival analyses were performed using the Kaplan-Meier method, and univariate and multivariate analyses were performed using the Cox proportional hazard model. The results were compared with those for a group of 193 early tongue-cancer patients who underwent treatment using iridium pins. The 5-year cause-specific survival and local control rates of the 198Au grains group were 71% and 68%, respectively, both of which were 16% lower than the corresponding rates for the 192Ir pins group. Our study demonstrated that as the last curative treatment available, 198Au grain implantation could be used to achieve moderate treatment results for early tongue cancer in patients of advanced age or poor performance status.