Takahiro Ochiai

Dr. Takahiro Ochiai


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 November 2023 in General Thoracic and Cardiovascular Surgery Cases
Verified
Journal Article
Open access
PDF file
TOTakahiro Ochiai
Takahiro Ochiai
STShinsuke Takeno
Shinsuke Takeno
FKFumiaki Kawano
Fumiaki Kawano
KTKousei Tashiro
Kousei Tashiro
ANAtsushi Nanashima
Atsushi Nanashima
KDKouichi Doi
Kouichi Doi
Background: Black esophagus, or acute esophageal necrosis (AEN), is a rare disease with a poor prognosis in which the esophageal mucosa is black in color. We report a case of esophageal perforation due to AEN that was successfully treated. Case presentation: An 88-year-old woman presented to her local hospital with the chief complaint of abdominal pain. Endoscopic and radiological examinations revealed esophageal perforation due to AEN and duodenal perforation. Omental patch repair was performed for the esophageal perforation, and the duodenal ulcer perforation was treated by simple closure and gastrojejunostomy at the local hospital. Following refractory esophageal and duodenal perforations after the initial surgery, the patient was transferred to our hospital where emergent surgery was performed, comprising thoracoscopic esophagectomy, cervical esophagostomy, T-tube drainage, and omentopexy for duodenal perforation, as well as thoracic and abdominal drainage. Mucosal regeneration of the esophagostomy was confirmed endoscopically on postoperative day 19. Conclusions: Appropriate surgical intervention may be an optimal option in patients with esophageal perforation due to AEN.

12 June 2025 in Cancers
Verified
Journal Article
Open access
PDF file
MNMasatoshi Nakagawa
Masatoshi Nakagawa
MNMasanobu Nakajima
Masanobu Nakajima
MYMasaki Yoshimatsu
Masaki Yoshimatsu
YUYu Ueta
Yu Ueta
NINoboru Inoue
Noboru Inoue
KKKazuyuki Kojima
Kazuyuki Kojima
Background: The incidence of esophagogastric junction cancer (EGJC) is increasing in both Western and Eastern countries. Despite this trend, a globally accepted treatment strategy remains elusive due to the tumor’s anatomical complexity and variability in clinical practice. Aim: This review aims to provide a comprehensive overview of current evidence regarding EGJC treatment, focusing on the surgical approach, extent of lymph node dissection, and perioperative therapy. Special attention is given to regional differences and the implications of recent clinical trials. Findings: Transhiatal and minimally invasive surgical approaches have demonstrated favorable safety profiles, particularly for Siewert type II tumors. Lymph node dissection strategies are increasingly tailored based on the extent of esophageal invasion. Pre- and postoperative chemotherapy and chemoradiotherapy are standard in the West, while East Asian countries are gradually adopting these approaches through trials such as RESOLVE (China) and PRODIGY (Korea). Immunotherapy has also emerged as a promising option following the CheckMate 577 trial. Conclusions: EGJC requires individualized treatment planning based on tumor characteristics and regional practices. While ongoing trials continue to inform optimal management, international collaboration and a stepwise, biomarker-informed approach will be essential to harmonize treatment strategies for this anatomically and therapeutically complex disease.

27 February 2025 in Turkish Journal of Surgery
Verified
Journal Article
Open access
ANAtsushi Nanashima
Atsushi Nanashima
JAJunichi Arai
Junichi Arai
MHMasahide Hiyoshi
Masahide Hiyoshi
NINaoya Imamura
Naoya Imamura
THTakeomi Hamada
Takeomi Hamada
WTWada Takashi
Wada Takashi
Clinical significance of para-aortic lymph node metastasis for prognosis in patients with pancreaticobiliary cancer who underwent radical surgical resections - Turkish Journal of Surgery

2 September 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
YUYu Ueta
Yu Ueta
MNMasanobu Nakajima
Masanobu Nakajima
MYMasaki Yoshimatsu
Masaki Yoshimatsu
TOTakahiro Ochiai
Takahiro Ochiai
STShuhei Takise
Shuhei Takise
KKKazuyuki Kojima
Kazuyuki Kojima
Background: Immune checkpoint inhibitors (ICIs) such as pembrolizumab (Pem) have demonstrated clinical benefits in esophageal cancer. Cisplatin, 5-fluorouracil, and Pem combination (CF plus Pem) has emerged as a promising first-line regimen. However, dose reduction of cytotoxic agents is necessary in real-world practice in patients with advanced age and/or renal dysfunction. This study aimed to evaluate the real-world effectiveness and safety of CF plus Pem therapy and assess survival outcomes based on the initial dose intensity. Methods: We retrospectively analyzed patients with unresectable or recurrent esophageal cancer who received CF plus Pem between February 2022 and February 2025. Clinical data, including patient characteristics, treatment details, tumor response, adverse events, and survival outcomes, were collected and analyzed. Results: We included 54 patients (median age, 72.5 years; 74.1% male). The initial CF dose was reduced in 55.6% of the patients. The overall response and disease control rates were 55.6% and 81.5%, respectively. The median overall survival (OS) and progression-free survival (PFS) were 18.6 and 6.5 months, respectively, with no significant differences observed among groups based on dose reduction, age, or change in treatment interval. Grade ≥3 adverse events occurred in 16.7% of patients, with fewer events and higher treatment continuity in the dose-reduction group. Conclusions: Thus, CF plus Pem therapy is effective and tolerable in real-world settings. Initial dose reduction does not compromise survival and supports individualized dosing strategies for esophageal cancer treatment.

21 August 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
ANAtsushi Nanashima
Atsushi Nanashima
JAJunichi Arai
Junichi Arai
MHMasahide Hiyoshi
Masahide Hiyoshi
NINO Imamura
NO Imamura
THTakeomi Hamada
Takeomi Hamada
YSYuichiro Sato
Yuichiro Sato
Background: We investigated the significance of the para-aortic node (PALN) and other regional node metastases (RLN), reflecting malignant histological findings or poor patient prognosis, in patients with biliary duct cancers (BDC) and pancreatic carcinomas (PC) who underwent radical resections at two institutes. Methods: Conventional clinicopathological factors, including metastasis to the PALN and RLN, and surgical outcomes or long-term prognosis in 181 PC and 116 BDC patients between 1994 and 2022 were examined. Results: In patients with PC, cancer metastasis was observed in the RLN and PALN in 54% and 9% of patients, respectively. In patients with BDC, cancer metastasis was observed in the RLN and PALN in 39% and 9% of patients, respectively. Disease-free survival (DFS) and overall survival (OS) in patients with BDC and PALN metastasis were significantly lower than those without PALN metastasis; however, several patients survived over three years. Multivariate analysis revealed that, in patients with BDC, PALN metastasis was an independently related factor of OS, and RLN was an independently related factor for DFS, respectively (p

1 December 2024 in Turkish Journal of Surgery
Verified
Journal Article
Open access
PDF file
ANAtsushi Nanashima
Atsushi Nanashima
MHMasahide Hiyoshi
Masahide Hiyoshi
NINaoya Imamura
Naoya Imamura
THTakeomi Hamada
Takeomi Hamada
YTYuki Tsuchimochi
Yuki Tsuchimochi
TOTakahiro Ochiai
Takahiro Ochiai
Objective: We examined the relation between several fibrotic markers reflecting liver parenchymal injury and conventional liver function or surgical outcomes in 67 patients with cholangiocarcinoma who underwent biliary drainage for obstructive jaundice followed by surgical resection. Material and Methods: We examined conventional clinicopathological factors, six hepatic fibrosis parameters, including platelet count, hyaluronic acid, Mac-2 binding protein glycosylation isomer (M2BPGi), type IV collagen 7S, aspartate aminotransferase-to-platelet ratio index (APRI), and FIB-4 index before hepatectomy, and surgical outcomes or long-term prognosis. Results: Obstructive jaundice was observed in 57% of the patients, a history of biliary diseases in 7.5%, and chronic hepatic injuries in 17.9%. M2BPGi was significantly higher in patients with obstructive jaundice as the primary sign (p< 0.05), the FIB-4 index was significantly correlated with patient age (p< 0.01), and serum hyaluronic acid and T4C7 levels were significantly increased in distal cholangiocarcinoma (CC). No markers were associated with the histological hepatic fibrotic index, tumor-related factors, or postoperative morbidities. Tumor relapse was observed in 37% of patients, and cancer-related death was observed in 25%. A higher FIB-4 index was significantly associated with shorter cancer-free survival (p< 0.05). Cox multivariate analysis showed that bilirubin levels, poor histological cancer differentiation, and absence of fibrotic markers were associated with cancer-free, cancer-specific overall, and overall survival. Conclusion: Although a sufficient relation exists between these markers and elastographic or histological fibrotic indexes, the clinical significance of measuring conventional fibrotic markers might no longer be necessary in future studies.