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Dive into the research topics where Takeshi Akiba is active.

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Featured researches published by Takeshi Akiba.


American Journal of Clinical Oncology | 2002

Prognostic factors of reirradiation for recurrent head and neck cancer.

Yukio Ohizumi; Yoshifumi Tamai; Satoshi Imamiya; Takeshi Akiba

We analyzed outcomes and prognostic factors to assess the value of reirradiation for recurrent head and neck cancer. Forty-four patients with recurrent squamous-cell carcinoma had undergone external beam reirradiation with cumulative dosing of more than 80 Gy. Six and 38 cases exhibited recurrent stage III and stage IV cancers, respectively. The complete response rate was 32%. Median relapse-free survival time was 4 months, and the 5-year survival was 6%. The major prognostic factor was anatomical location (p < 0.0001). Favorable sites were the nasopharynx, larynx, or oropharynx; unfavorable sites were the oral cavity, nasal cavity, or hypopharynx. Poorly differentiated cancer, no prior surgery, cumulative dose more than 125 Gy, and overlapping field less than 40 cm2 between the initial and reirradiation fields were also favorable factors. Multivariate analysis revealed that anatomical location and overlapping field were significant (0.001 and 0.019, respectively) in relapse-free survival. On exclusion of anatomical location from the analysis, history of prior surgery, and cumulative dose were significant (p = 0.002 and p = 0.023, respectively). Severe late complications occurred in only 1 of 14 (7%) patients followed up for longer than 1 year. Reirradiation would be indicative for nasopharyngeal, oropharyngeal, or laryngeal cancer with small overlapping field, or cancer receiving a cumulative dose more than 125 Gy without prior surgery.


Oncology | 2011

Phase I/II Study of Preoperative Concurrent Chemoradiotherapy with S-1 for Locally Advanced, Resectable Rectal Adenocarcinoma

Sotaro Sadahiro; Toshiyuki Suzuki; Akira Tanaka; Kazutake Okada; Akemi Kamijo; Chieko Murayama; Takeshi Akiba; Yuko Nakayama

Purpose: To assess the maximum tolerability of a combination of S-1 and preoperative radiotherapy and to evaluate the feasibility and activity in patients with locally advanced rectal cancer. Methods: Patients (n = 30) with adenocarcinoma of the middle or lower rectum were enrolled in a phase I (n = 9) and/or phase II (n = 21) trial. A total dose of 45 Gy was delivered in 25 fractions over 5 weeks, and S-1 was orally administered twice a day on days 1–14 and 22–35. Surgical resection was scheduled 4–8 weeks after the completion of chemoradiation. Results: In phase I, the recommended dose (RD) of S-1 was 80 mg/m2/day, and the maximum-tolerated dose was never reached. A total of 27 cases, including the 6 RD cases in phase I, were enrolled in phase II. In phase II, a pathological complete response (pCR) was observed in 6/27 patients (22%), pathological downstaging was observed in 21/27 patients (78%), and a tumor volume reduction of 69 ± 22% was obtained. These results were similar to the previously reported pCR rates of 16–18%, pathological downstaging rates of 49–59%, and tumor volume reduction of 68% after chemoradiotherapy with capecitabine. Grade 3 adverse events consisted of one case of leukopenia (4%), 2 cases of anemia (7%) and 3 cases of diarrhea (11%). Overall, the adverse events were very mild. Hand-foot syndrome was not observed. Conclusion: The efficacy of chemoradiotherapy with S-1 seems to be equivalent to the efficacy reported for chemoradiotherapy with capecitabine, but the adverse events were much milder, although further study is warranted.


International Journal of Radiation Oncology Biology Physics | 2013

Biopsy Specimens Obtained 7 Days After Starting Chemoradiotherapy (CRT) Provide Reliable Predictors of Response to CRT for Rectal Cancer

Toshiyuki Suzuki; Sotaro Sadahiro; Akira Tanaka; Kazutake Okada; Hiroko Kamata; Akemi Kamijo; Chieko Murayama; Takeshi Akiba; Shuichi Kawada

PURPOSE Preoperative chemoradiation therapy (CRT) significantly decreases local recurrence in locally advanced rectal cancer. Various biomarkers in biopsy specimens obtained before CRT have been proposed as predictors of response. However, reliable biomarkers remain to be established. METHODS AND MATERIALS The study group comprised 101 consecutive patients with locally advanced rectal cancer who received preoperative CRT with oral uracil/tegafur (UFT) or S-1. We evaluated histologic findings on hematoxylin and eosin (H&E) staining and immunohistochemical expressions of Ki67, p53, p21, and apoptosis in biopsy specimens obtained before CRT and 7 days after starting CRT. These findings were contrasted with the histologic response and the degree of tumor shrinkage. RESULTS In biopsy specimens obtained before CRT, histologic marked regression according to the Japanese Classification of Colorectal Carcinoma (JCCC) criteria and the degree of tumor shrinkage on barium enema examination (BE) were significantly greater in patients with p21-positive tumors than in those with p21-negative tumors (P=.04 and P<.01, respectively). In biopsy specimens obtained 7 days after starting CRT, pathologic complete response, histologic marked regression according to both the tumor regression criteria and JCCC criteria, and T downstaging were significantly greater in patients with apoptosis-positive and p21-positive tumors than in those with apoptosis-negative (P<.01, P=.02, P=.01, and P<.01, respectively) or p21-negative tumors (P=.03, P<.01, P<.01, and P=.02, respectively). The degree of tumor shrinkage on both BE as well as MRI was significantly greater in patients with apoptosis-positive and with p21-positive tumors than in those with apoptosis-negative or p21-negative tumors, respectively. Histologic changes in H&E-stained biopsy specimens 7 days after starting CRT significantly correlated with pathologic complete response and marked regression on both JCCC and tumor regression criteria, as well as with tumor shrinkage on BE and MRI (P<.01, P<.01, P<.01, P<.01, and P=.03, respectively). CONCLUSIONS Immunohistochemical expressions of p21 and apoptosis together with histologic changes on H&E-stained biopsy specimens obtained 7 days after starting CRT are strong predictors of the response to CRT.


Oncology | 2015

Phase II Study of Preoperative Concurrent Chemoradiotherapy with S-1 plus Bevacizumab for Locally Advanced Resectable Rectal Adenocarcinoma

Sotaro Sadahiro; Toshiyuki Suzuki; Akira Tanaka; Kazutake Okada; Gota Saito; Akemi Kamijo; Takeshi Akiba; Shuichi Kawada

Objective: A single-arm phase II clinical trial was conducted to evaluate the safety and efficacy of preoperative chemoradiotherapy (CRT) with concurrent S-1, bevacizumab, and radiation in patients with locally advanced rectal cancer (LARC). Methods: Fifty-two patients with LARC were enrolled. A total dose of 45 Gy was delivered in 25 fractions over 5 weeks, S-1 was administered orally twice a day on days 1-14 and 22-35, and bevacizumab was administered on days 1, 15, and 29. Surgical resection was scheduled 8 weeks (6-10 weeks) after completing the CRT. Results: All 52 patients underwent R0 radical surgery. Sphincter preservation was possible in 38 (73.1%) patients. A pathologic complete response was obtained in 10 (19.2%) patients, a pathologic downstaging was achieved in 37 (71.2%) patients, and the tumor shrinkage rate was 77.1%. The only grade 3 adverse events were leukopenia and rash in 1 (1.9%) patient. The rate of postoperative complications was 28.8%. Anastomotic leakage occurred in 9 (23.7%) of the 38 patients who underwent sphincter-preserving surgery. Perineal wound dehiscence developed in 2 (14.3%) of the 14 patients who received an abdominoperineal resection. Conclusions: Adding bevacizumab to S-1 clearly increased the incidence of wound-related complications, with no distinct enhancement of tumor response. i 2014 S. Karger AG, Basel


Japanese Journal of Clinical Oncology | 2012

Re-irradiation for Metastatic Brain Tumors with Whole-brain Radiotherapy

Takeshi Akiba; Etsuo Kunieda; Asuka Kogawa; Tetsuya Komatsu; Yoshifumi Tamai; Yukio Ohizumi

OBJECTIVE To determine whether second whole-brain irradiation is beneficial for patients previously treated with whole-brain irradiation. METHODS A retrospective analysis was done for 31 patients with brain metastases who had undergone re-irradiation. Initial whole-brain irradiation was performed with 30 Gy/10 fractions for 87% of these patients. Whole-brain re-irradiation was performed with 30 Gy/10 fractions for 42% of these patients (3-40 Gy/1-20 fractions). Three patients underwent a third whole-brain irradiation. RESULTS The median interval between the initial irradiation and re-irradiation was 10 months (range: 2-69 months). The median survival time after re-irradiation was 4 months (range: 1-21 months). The symptomatic improvement rate after re-irradiation was 68%, and the partial and complete tumor response rate was 55%. Fifty-two percent of the patients developed Grade 1 acute reactions. On magnetic resonance imaging, brain atrophy was observed in 36% of these patients after the initial irradiation and 74% after re-irradiation. Grade ≥2 encephalopathy or cognitive disturbance was observed in 10 patients (32%) after re-irradiation. Based on univariate analysis, significant factors related to survival after re-irradiation were the location of the primary cancer (P = 0.003) and the Karnofsky performance status at the time of re-irradiation (P = 0.008). A Karnofsky performance status ≥70 was significant based on multivariate analysis (P = 0.050). CONCLUSIONS Whole-brain re-irradiation for brain metastases placed only a slight burden on patients and was effective for symptomatic improvement. However, their remaining survival time was limited and the incidence of cognitive disturbance was rather high.


Journal of Surgical Oncology | 2014

Relationship between histologic response and the degree of tumor shrinkage after chemoradiotherapy in patients with locally advanced rectal cancer

Toshiyuki Suzuki; Sotaro Sadahiro; Akira Tanaka; Kazutake Okada; Gota Saito; Akemi Kamijo; Takeshi Akiba; Shuichi Kawada

Preoperative chemoradiotherapy (CRT) significantly decreases local recurrence in advanced rectal cancer. We studied whether the degree of tumor shrinkage can be used as a predictor of histologic response.


Molecular and Clinical Oncology | 2013

Clinical characteristics of brain metastases from lung cancer according to histological type: Pretreatment evaluation and survival following whole-brain radiotherapy.

Tetsuya Komatsu; Etsuo Kunieda; Yukio Oizumi; Yoshifumi Tamai; Takeshi Akiba

The histological type of lung cancer in patients with brain metastases may affect response to treatment and survival. We evaluated the clinical characteristics of brain metastases from lung cancer according to histological type in 70 consecutive patients with brain metastases from histologically confirmed lung cancer, who had been previously treated with whole-brain radiotherapy (WBRT). Histological type was divided into three categories: adenocarcinoma, small-cell lung carcinoma (SCLC) and other non-small cell lung cancer (NSCLC). The number, size and maximum diameter of brain metastases, the size and maximum diameter of peritumoral edema, the ratio of tumor and peritumoral edema, the asymptomatic ratio, the tumor size reduction rate, the complete response (CR) rate, the intracranial progression-free survival (PFS) and the overall survival (OS) were also evaluated. The median survival time for all patients was 26.2 weeks. Patients with SCLC exhibited a significantly smaller edema size and maximum diameter of edema compared to patients with other NSCLC (P=0.016 and 0.010, respectively). The ratio of tumor and peritumoral edema was also significantly lower in patients with SCLC compared to that in patients with adenocarcinoma and other NSCLC (P= 0.001). Significant differences in intracranial PFS and OS between adenocarcinoma and other NSCLC were also observed (P=0.018 and 0.004, respectively). Patients with adenocarcinoma who were treated with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) following WBRT, demonstrated a significant improvement in intracranial PFS and OS (P=0.008 and 0.004, respectively). The findings presented in this study may provide useful information for the management of brain metastases. Patients with SCLC exhibit a tendency to develop peritumoral edema to a lesser extent, compared to patients with other histological tumor types. Findings in the present study suggest that patients with adenocarcinoma, particularly those treated with EGFR-TKIs, exhibit improved survival rates.


Lung Cancer | 2017

Stereotactic body radiotherapy for operable early-stage non-small cell lung cancer

Takahisa Eriguchi; Atsuya Takeda; Naoko Sanuki; Yuichiro Tsurugai; Yousuke Aoki; Yohei Oku; Yu Hara; Takeshi Akiba; Naoyuki Shigematsu

PURPOSE To analyze outcomes of stereotactic body radiotherapy (SBRT) for operable patients with early-stage non-small cell lung cancer (NSCLC) and to evaluate factors associated with outcomes. METHODS We retrospectively analyzed operable patients with NSCLC, staged as cT1-2N0M0, treated with SBRT between 2006 and 2015. Both biopsy-proven and clinically diagnosed NSCLC were included. Local control and survival rates were calculated and compared between subsets of patients. We investigated factors associated with outcomes. RESULTS We identified 88 operable patients among 661 patients with cT1-2N0M0 NSCLC. The median age was 79 years (range: 55-88). The median follow-up time after SBRT was 40 months (range: 4-121). Fifty-nine patients had been pathologically diagnosed and the other 29 had been clinically diagnosed as having NSCLC. Local control, cause-specific survival (CSS) and overall survival (OS) at 3 years were 91%, 97% and 90% for T1, and 100%, 82% and 74% for T2, respectively. The CSS and OS at 3 years were 100% and 100% for GGO and 83% and 59% for solid tumors, respectively (p=0.005). On univariate analysis, age and T stage were significantly associated with CSS, and age, the Charlson Comorbidity Index (CCI), and opacity were significantly associated with OS. On multivariate analysis, age and CCI were significantly associated with OS. As for toxicities, Grades 0, 1, 2 and 3 radiation pneumonitis occurred in 37.5%, 47.7%, 13.6% and 1.1% of patients, respectively. No Grade 4 or 5 radiation pneumonitis occurred, and no other toxicities of Grade 2 or above were observed. CONCLUSION Outcomes of SBRT for operable early stage NSCLC were as good as previous SBRT and surgery studies. Further investigation for selecting good SBRT candidates is warranted in high-risk operable patients.


Journal of Thoracic Disease | 2018

Clarithromycin mitigates radiation pneumonitis in patients with lung cancer treated with stereotactic body radiotherapy

Atsuya Takeda; Yuichiro Tsurugai; Naoko Sanuki; Masaharu Shinkai; Tomikazu Mizuno; Yousuke Aoki; Yohei Oku; Takeshi Akiba; Yu Hara; Etsuo Kunieda

Background Radiation pneumonitis is a critical pulmonary toxicity after irradiation of the lung. Macrolides including clarithromycin (CAM) are antibiotics. They also have immunomodulatory properties and are used to treat respiratory inflammatory diseases. Radiation pneumonitis has similar pathology to them. Adverse reactions to macrolides are few and self-limited. We thus administered CAM to patients with high-risk factors for radiation pneumonitis, and retrospectively investigated whether CAM mitigated radiation pneumonitis following stereotactic body radiotherapy (SBRT). Methods Among consecutive patients treated with SBRT, we retrospectively examined lung cancer patients treated with a total dose of 40-60 Gy in 5-10 fractions and followed ≥6 months. Since January 2014, CAM has been administered in patients with pretreatment predictable radiation pneumonitis high-risk factors, including idiopathic interstitial pneumonias (IIPs), and elevated Krebs von den Lungen-6 (KL-6) and/or surfactant protein D (SP-D), and in patients developing early onset radiation pneumonitis. Results Five hundred and eighty eligible patients were identified and divided into 445 patients during the non-CAM-administration era (non-CAM-era) (before December 2013) and 136 patients during the CAM-administration era (CAM-era) (after January 2014). Median follow-up durations were 38.0 and 13.9 months, respectively. The rates of radiation pneumonitis ≥ grade 2 and ≥ grade 3 were significantly lower in CAM-era (grade ≥2, 16% vs. 9.6%, P=0.047; grade ≥3, 3.8% vs. 0.73%, P=0.037). For patients with the pretreatment predictable high-risk factors, the rate of radiation pneumonitis ≥ grade 3 was significantly lower, and that of grade ≥2 had a lower tendency (grade ≥3, 7.2% vs. 0%, P=0.011; grade ≥2, 21% vs. 9.6%, P=0.061). For patients developing early onset radiation pneumonitis, the rate of radiation pneumonitis ≥ grade 3 was also significantly lower (23% vs. 0%, P<0.05). Multivariate analysis revealed that dose-volumetric factor, the pretreatment predictable high-risk factors and non-CAM-administration era were significantly associated with or trended toward radiation pneumonitis ≥ grade 2 and ≥ grade 3. Conclusions CAM mitigated radiation pneumonitis following SBRT. The efficacy of CAM should be confirmed in prospective studies.


Journal of Radiation Research | 2018

National survey of myeloablative total body irradiation prior to hematopoietic stem cell transplantation in Japan: survey of the Japanese Radiation Oncology Study Group (JROSG)

Naoya Ishibashi; Toshinori Soejima; Hiroki Kawaguchi; Takeshi Akiba; Masatoshi Hasegawa; Kouichi Isobe; Hitoshi Ito; Michiko Imai; Yasuo Ejima; Masaharu Hata; Keisuke Sasai; Emiko Shimoda; Toshiya Maebayashi; Masahiko Oguchi; Tetsuo Akimoto

Abstract A myeloablative regimen that includes total-body irradiation (TBI) before hematopoietic stem cell transplantation results in higher patient survival rates than achieved with regimens without TBI. The TBI protocol, however, varies between institutions. In October 2015, the Japanese Radiation Oncology Study Group initiated a national survey of myeloablative TBI (covering 2010–2014). Among the 186 Japanese institutions performing TBI, 90 (48%) responded. The 82 institutions that had performed myeloablative TBI during this period treated 2698 patients with malignant disease [leukemia (2082 patients, 77.2%), malignant lymphoma (378, 14%)] and 37 with non-malignant disease [severe aplastic anemia (20, 54%), inborn errors of metabolism (5, 14%)]. A linear accelerator was used at all institutions. The institutions were divided into 41 large and 41 small institutions based on the median number of patients. The long source–surface distance technique was the method of choice in the 34 institutions (82.9%) and the moving-couch technique in the 7 (17.1%) in the large institutions. The schedules most routinely used by the participating institutions consisted of 12 Gy/6 fractions/3 days (26 institutions, 63.5%) in the large institutions. The dose rate varied from 5 to 26 cGy/min. The lungs and lenses were routinely shielded in 23 large institutions (56.1%), and only the lungs in 9 large institutions (21.9%). At lung-shielding institutions, the most frequent maximum acceptable total dose for the lungs was 8 Gy (19 institutions, 27.5%). Our results reveal considerable differences in the TBI methods used by Japanese institutions and thus the challenges in designing multicenter randomized trials based on TBI.

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