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Dive into the research topics where Gota Saito is active.

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Featured researches published by Gota Saito.


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


Surgery | 2014

Randomized controlled trial comparing subcuticular absorbable suture with conventional interrupted suture for wound closure at elective operation of colon cancer.

Akira Tanaka; Sotaro Sadahiro; Toshiyuki Suzuki; Kazutake Okada; Gota Saito

BACKGROUND Subcuticular closure provides a superior cosmetic result in clean wounds. The aim of this work was to investigate the safety in terms of postoperative infection and cosmetic effectiveness of subcuticular wound closure after elective colon cancer surgery in clean-contaminated wounds. METHODS Patients who underwent elective resection of colon cancer were randomized to interrupted subcuticular and interrupted transdermal suture groups. The large bowel was prepared by mechanical washout with polyethylene glycol. All patients received metronidazole and kanamycin orally and flomoxef sodium once parenterally for antimicrobial prophylaxis. The primary end point was the incidence of incisional surgical-site infections within 30 days after operation. We assessed noninferiority of subcuticular suture within a margin of 10%. Analysis was by intent-to-treat. Secondary objectives include comparison of wound closure time, comfort, and cosmesis of the scar and satisfaction of patients. This study was registered with UMIN-CTR, UMIN000003005. RESULTS A total of 293 patients were randomized to the two groups. Incisional surgical-site infection rates were 11.0% (90% confidence interval 7.0-16.3%) for both groups. The relative risk of subcuticular suture was 1.00 (0.58-1.73, one-tail P = .57). Interrupted subcuticular suture was noninferior to interrupted transdermal suture (P = .0088). Throughout 6 months after operation, patients expressed a significant preference for the subcuticular suture technique, noting rapid relief from pain, decreased vascularity, and smaller width, although the procedure took twice as long. CONCLUSION Subcuticular suture did not increase the incidence of wound complications in elective colon cancer operation. Patients preferred a technique of interrupted subcuticular closure, citing better cosmetic results, and less pain.


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.


Oncology | 2017

Monitoring of Serum Carcinoembryonic Antigen Levels after Curative Resection of Colon Cancer: Cutoff Values Determined according to Preoperative Levels Enhance the Diagnostic Accuracy for Recurrence

Gota Saito; Sotaro Sadahiro; Hiroko Kamata; Hiroshi Miyakita; Kazutake Okada; Akira Tanaka; Toshiyuki Suzuki

Objectives: Serum carcinoembryonic antigen (CEA) has been widely used for postoperative surveillance for colorectal cancer. However, serum CEA has a poor diagnostic accuracy for detecting recurrence. We tested the hypothesis that determining cutoff values according to the preoperative serum CEA levels would enhance the diagnostic accuracy. Methods: Serum CEA was measured before and 1-6 months after surgery in 783 patients with curatively resected colon cancer from 2005 through 2013. The cutoff values during surveillance were determined separately according to preoperative serum CEA levels. Results: In patients with negative preoperative serum CEA, the diagnostic accuracy for recurrence was 89.1% when a postoperative cutoff value was set at 5 ng/mL. However, in patients with positive preoperative serum CEA, the diagnostic accuracy was 58.4% when a postoperative cutoff value was set at 5 ng/mL, and was 75.6% when a cutoff value was set at 8 ng/mL. Among patients with positive preoperative serum CEA, the recurrence-free survival rate was significantly lower in patients with a serum CEA of ≥8 ng/mL than those with a serum CEA of <8 ng/mL (p = 0.0018). Conclusions: The diagnostic accuracy of serum CEA for recurrence is enhanced by separately setting cutoff values according to preoperative serum CEA.


Oncology | 2015

A Phase II Trial of Combined Chemotherapy with Oral S-1 and 24-Hour Infusions of Irinotecan plus Bevacizumab in Patients with Metastatic Colorectal Cancer.

Sotaro Sadahiro; Toshiyuki Suzuki; Akira Tanaka; Kazutake Okada; Gota Saito; Akemi Kamijo

Objectives: Protracted low-dose infusion of irinotecan has been suggested to enhance antitumor activity. A phase II study was conducted to evaluate the safety and efficacy of oral S-1 combined with 24-hour infusion of irinotecan and intravenous bevacizumab for metastatic colorectal cancer (MCRC). Methods: The subjects were 79 patients with MCRC; 57 were chemotherapy naïve. Irinotecan (125 mg/m2) was administered as a 24-hour infusion on days 1 and 15, S-1 (80 mg/m2) was administered orally on days 1-14, and bevacizumab (5.0 mg/kg) was given on days 1 and 15. The treatment was repeated every 4 weeks. Results: Median follow-up was 20.0 months, and the mean number of cycles was 7. The overall response rate was 79.7% (95% CI, 69.2-88.0), 86.0% (95% CI, 74.2-93.7) for first-line and 63.6% (95% CI, 40.7-82.8) for second-line treatment. The median progression-free survival was 16.4 months (95% CI, 13.9-21.0) for first-line and 9.4 months (95% CI, 4.9-16.5) for second-line treatment. The median overall survival was not reached. Grade 3-4 toxicities were neutropenia (43%), leukopenia (20.3%), anorexia (19.0%), and diarrhea (10.1%). Toxicity was tolerable. Conclusions: Combination chemotherapy with oral S-1 and biweekly 24-hour infusions of irinotecan plus bevacizumab appears to be highly active and well tolerated both as first-line and second-line chemotherapy for MCRC.


International Journal of Clinical Oncology | 2017

Risk scores as useful predictors of perioperative complications in patients with rectal cancer who received radical surgery

Hiroshi Miyakita; Sotaro Sadahiro; Gota Saito; Kazutake Okada; Akira Tanaka; Toshiyuki Suzuki

BackgroundRectal cancer is associated with a higher rate of surgical complications. The ability to predict the risk of complications before treatment would facilitate the design of personalized treatment strategies optimally suited for each patient.MethodsWe retrospectively studied 260 patients with rectal cancer who underwent radical surgery to examine the relations between complications and 5 types of risk scores.ResultsComplications developed in 56 patients (21.5%). Nineteen patients had infectious complications, 16 had intestinal obstruction, and 12 had other complications. Twelve patients out of 187 patients who received low anterior resection had anastomotic leakage. Estimation of Physiologic Ability and Surgical Stress Comprehensive Risk Score (E-PASS CRS) and Neutrophil-to-lymphocyte Ratio (NLR) were significantly related to all complications, infectious complications, and anastomotic leakage. Surgical Apgar Score was significantly related to infectious complications. Prognostic Nutritional Index was significantly related to all complications and intestinal obstruction. Colorectal Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity was significantly related to all complications, and infectious complications. A multivariate analysis showed that body-mass index, E-PASS CRS, and NLR were independent risk factors for anastomotic leakage. In particular, NLR was the only score that could be evaluated before surgery.ConclusionsFive types of risk scores were useful methods for evaluating the risks of complications in patients with rectal cancer. NLR is a score that can be evaluated before surgery and predicted the risk of anastomotic leakage, suggesting that it is useful for assessing the need for a diverting colostomy.


Oncology | 2017

Relations of Changes in Serum Carcinoembryonic Antigen Levels before and after Neoadjuvant Chemoradiotherapy and after Surgery to Histologic Response and Outcomes in Patients with Locally Advanced Rectal Cancer

Gota Saito; Sotaro Sadahiro; Takashi Ogimi; Hiroshi Miyakita; Kazutake Okada; Akira Tanaka; Toshiyuki Suzuki

Objectives: The histologic response to neoadjuvant chemoradiotherapy (nCRT) has been intimately related to outcomes in locally advanced rectal cancer. Serum carcinoembryonic antigen (CEA) levels change after nCRT and after surgery as compared with before nCRT. Methods: The subjects were 149 patients with locally advanced rectal cancer who received nCRT between 2005 and 2013. The patients were divided into 4 groups according to the serum CEA levels: group 1, 55 patients with negative serum CEA levels before nCRT; group 2, 41 patients with positive serum CEA levels before nCRT that became negative after nCRT; group 3, 37 patients with positive serum CEA levels after nCRT that became negative after surgery; and group 4, 16 patients with positive serum CEA levels after nCRT as well as after surgery. Results: Pathological complete response, T downstaging, and tumor shrinkage were significantly higher in group 1 than in other groups. Disease-free survival was significantly poorer in group 4. The lack of a decrease in the serum CEA level in group 4 was most likely attributed to the persistence of micrometastases outside the resection field. Conclusions: Changes in serum CEA levels measured before nCRT, after nCRT, and after surgery can be used to reliably predict the histologic response to nCRT and outcomes.


Oncology Letters | 2018

Retrospective study of regorafenib and trifluridine/tipiracil efficacy as a third‑line or later chemotherapy regimen for refractory metastatic colorectal cancer

Akira Tanaka; Sotaro Sadahiro; Toshiyuki Suzuki; Kazutake Okada; Gota Saito; Hiroshi Miyakita

Regorafenib and trifluridine/tipiracil (TAS-102) are novel antitumor agents for patients with refractory metastatic colorectal cancer. However, it is unclear which patients may derive a survival benefit from these drugs in real-life clinical practice. We evaluated retrospectively the efficacy and safety of regorafenib and TAS-102 at a single institution between June 2013 and November 2015. Cox regression analysis was carried out to obtain predictive scores (the nearest integers of hazard ratio) for survival benefit. Forty-four patients treated with regorafenib or TAS-102 were included in the analysis; among them, 17 received crossover treatment. The median overall survival (OS) was 9.1 months for regorafenib and 9.3 months for TAS-102, and the corresponding values after crossover were 7.1 and 5.3 months, respectively. OS was not correlated to relative dose intensity, but was proportional to the total administered dose of each drug. Adverse events were tolerable even after crossover. We identified three variables as significant for prediction of OS with good discrimination (C-statistic=0.70): Poor Eastern Cooperative Oncology Group performance status, time since diagnosis of metastatic disease ≤18 months, and previous chemotherapy continued ≥2 months beyond progression were all predictors of poor OS. Regorafenib and TAS-102 can be recommended for patients with better performance status and slow progression of metastatic disease. Optimal survival benefit was provided by prompt administration of either drug after failure of previous chemotherapy, with flexible titration to the optimal dose for each individual patient.


Oncology | 2018

The Number of Natural Killer Cells in the Largest Diameter Lymph Nodes Is Associated with the Number of Retrieved Lymph Nodes and Lymph Node Size, and Is an Independent Prognostic Factor in Patients with Stage II Colon Cancer

Kazutake Okada; Sotaro Sadahiro; Lin Fung Chan; Takashi Ogimi; Hiroshi Miyakita; Gota Saito; Akira Tanaka; Toshiyuki Suzuki

Objective: We previously reported that the largest diameter of retrieved lymph nodes (LNs) correlates with the number of LNs and is a prognostic factor in stage II colon cancer. We examine whether T, B, and natural killer (NK) cells in LNs are related to the number of LNs and survival. Methods: The subjects comprised 320 patients with stage II colon cancer. An LN with the largest diameter was selected in each patient. The positive area ratios of cells that stained for CD3 and CD20, and the numbers of CD56-positive cells were measured. Results: The CD3-positive area ratio was 0.39 ± 0.08 and CD20-positive area ratio was 0.42 ± 0.10. The mean number of CD56-positive cells was 19.3 ± 22.7. The area ratios of B cells and T cells and the number of NK cells were significantly related to the sizes of the largest diameter LNs. The number of NK cells significantly correlated with the number of LNs and was an independent prognostic factor. On multivariate analysis, pathological T stage (T4 or T3; HR 4.71; p < 0.001) and the number of CD56-positive cells (high or low; HR 0.22; p < 0.001) were found to be independent prognostic factors. Conclusions: The number of NK cells in the largest diameter LNs can most likely be used as a predictor of recurrence.


Oncology | 2018

Outcomes of Local Excision plus Chemoradiotherapy in Patients with T1 Rectal Cancer

Toshiyuki Suzuki; Sotaro Sadahiro; Akira Tanaka; Kazutake Okada; Gota Saito; Hiroshi Miyakita; Takeshi Akiba; Hiroshi Yamamuro

Objective: The National Comprehensive Cancer Network (NCCN) guidelines recommend local excision and observation as standard treatment for selected patients with clinical T1N0M0 rectal cancer. In patients with pathological T1 (pT1) rectal cancer who received local excision, the local recurrence rate is at least 10%. We studied oncological outcomes in patients with pT1 rectal cancer who received chemoradiotherapy (CRT) after local excision. Methods: Local excision was performed in 65 patients with clinical T1N0M0 rectal cancer (≤8 cm from the anal verge, tumor size < 30 mm, well or moderately differentiated adenocarcinoma). The patients received CRT (40 or 45 Gy in 1.8–2.0 fractions with concurrent oral UFT [tegafur/uracil] or S-1 [tegafur/gimeracil/oteracil]) after confirmation of pT1 and negative margins. Results: Patients who had pT2 cancer or who did not provide informed consent were excluded. The remaining 50 patients additionally received CRT. The CRT was completed in 48 patients (96%). The median follow-up period was 71 months. Local recurrence occurred in 1 patient (2%). Distant metastases occurred in 3 patients (6%). The 5-year disease-free survival rate was 86%, and the 5-year overall survival rate was 92%. Conclusions: Our study suggested that multidisciplinary treatment with local excision plus CRT can be used as a treatment option in selected patients with clinical T1N0M0 rectal cancer.

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