Tanaka, Masayuki

写真a

Affiliation

School of Medicine, Department of Surgery (General and Gastroenterological Surgery) (Shinanomachi)

Position

Instructor

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Papers 【 Display / hide 】

  • Safety and efficacy of pancreaticogastrostomy for hepatopancreatoduodenectomy compared to pancreaticojejunostomy for perihilar cholangiocarcinoma

    Nakano Y., Abe Y., Udagawa D., Kitago M., Hasegawa Y., Hori S., Tanaka M., Uemura S., Odaira M., Mihara K., Nishiyama R., Chiba N., Hayatsu S., Kawachi S., Kitagawa Y.

    World Journal of Surgical Oncology 23 ( 1 )  2025.12

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    Background: Hepatopancreatoduodenectomy (HPD) is one of the most challenging surgeries for perihilar cholangiocarcinoma. Postoperative pancreatic fistula (POPF) is a critical and fatal complication. The safety and efficacy of pancreaticogastrostomy (PG) for HPD compared to pancreaticojejunostomy (PJ) remain unclear. In this study, we aimed to investigate and compare the short-term outcomes of PG and PJ for HPD in terms of the POPF rate. Methods: Two groups of patients (PG group vs. PJ group) were retrospectively compared between January 2013 and January 2024. The reconstruction method was changed from PJ to PG in March 2021. Results: A total of 50 patients were enrolled in this study. The PG and PJ groups comprised 15 (30.0%) and 35 (70.0%) patients, respectively. In the PJ group, three (8.6%) patients died after surgery because of clinically relevant POPF (CR-POPF), intraabdominal bleeding, and post-hepatectomy liver failure. The operative time was longer in the PG group (909 min vs. 706 min, P = 0.020); however, the CR-POPF rate was lower in the PG group than in the PJ group (0 [0%] vs. 19 [54.3%], P < 0.001). Moreover, the number of patients who developed massive postoperative ascites (≥ 1,500 mL/day) was lower in the PG group than in the PJ group (3 [20.0%] vs. 16 [45.7%] patients, P = 0.028). Conclusions: Changing the method of pancreatic reconstruction for HPD from PJ to PG improved the short-term outcomes of patients at our institution. PG reconstruction is safe and effective for HPD as it reduces the incidence of CR-POPF.

  • Laparoscopic cholecystectomy with synchronous navigation of ICG fluorescence and Yellow Enhance mode

    Sonoda K., Abe Y., Kitago M., Yagi H., Hasegawa Y., Hori S., Tanaka M., Nakano Y., Kojima H., Kitagawa Y.

    Asian Journal of Surgery 48 ( 7 ) 4186 - 4187 2025.07

    ISSN  10159584

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    Technique: Laparoscopic cholecystectomy (LC), widely performed for gallbladder (GB) diseases poses risks of severe complications. To minimize these risks, Tokyo Guidelines 2018 advocated for “safe steps in LC for acute cholecystitis (AC)” including “maintaining the plane of dissection on the GB surface throughout LC”. Moreover, the dissection along the inner layer of the subserosa (SS-inner) of GB helps surgeons avoid bile duct or vascular injury. This step occasionally becomes challenging when distinguishing the GB surface from adjacent fat. ICG, injected into biliary tract, illuminates in green under Infra-red (IR) mode and facilitates the identification of biliary tract. Otherwise, Yellow Enhance (YE) mode developed by Olympus Corporation, which highlights yellow-colored tissues by converting orange-yellow tissues to a clearer yellow, improves the contrast between anatomical structures. Results: In a case of AC following percutaneous transhepatic gallbladder drainage (PTGBD), we applied both ICG fluorescence and YE mode. The ICG injected from PTGBD illuminated the GB surface in green, while YE mode highlighted the fatty tissue in a clearer yellow, facilitating the distinction between these two tissues and the accurate dissection along the SS-inner. An additional advantage of injecting ICG from PTGBD, or from the cannulation tube intraoperatively inserted to GB, over intravenous administration is that the GB surface can be illuminated in cases of GB stone incarceration. Conclusion: The combination of ICG fluorescence and YE mode encourages surgeons to identify the boundary between the GB surface and the surrounding fatty tissues, which assists the accurate dissection along the SS-inner.

  • Potential Impact of Screening Examinations on Prognosis of De Novo Malignancies in Adult Patients After Liver Transplantation

    Uemura S., Hasegawa Y., Obara H., Kitago M., Yagi H., Abe Y., Hori S., Tanaka M., Nakano Y., Kitagawa Y.

    Livers 5 ( 2 )  2025.06

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    Background: De novo malignancies (DNMs) after liver transplantation (LT) are a major cause of long-term mortality. However, no definitive screening protocol has been established due to their diversity. This study aimed to evaluate DNM diagnosis methods, screening protocols, and prognoses. Methods: This retrospective study included 231 adult LT recipients from April 1997 to March 2021. Disease-specific survival (DSS) was analyzed to assess the impact of screening on prognosis. Most recipients underwent serum tests every three months, annual gastrointestinal endoscopy, and chest-abdominal CT as part of routine surveillance. Results: Twenty-five DNMs were diagnosed in 22 patients, with median age of 61 years (range, 23–72), of whom 13 (59.1%) were female. The duration from transplantation to DNM diagnosis of DNM was 88 months (range, 4–195). DNM was diagnosed as follows: seven patients (31.8%) through screening (screening group) and 15 patients (68.2%) by other means (non-screening group). Curative treatment was achieved in all of the patients diagnosed by screening, whereas it was possible in only 60.0% of patients diagnosed by other means (p = 0.026). DSS in the screening group was significantly longer than that in the non-screening group (p = 0.024). Conclusions: While screening was associated with earlier-stage diagnosis and improved outcomes in some patients, the overall efficacy of the protocol requires further validation in larger studies.

  • Comparable impact of lymph node metastases in T2 gallbladder cancer on postoperative prognosis irrespective of the extent of the metastases: A retrospective analysis

    Kishi Y., Sugiura T., Mizuno T., Ito H., Takahashi Y., Noji T., Abe Y., Otsuka S., Kawakatsu S., Kato A., Tanaka M., Ebata T., Hirano S.

    Journal of Hepato Biliary Pancreatic Sciences 32 ( 6 ) 443 - 451 2025.06

    ISSN  18686974

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    Background: Lymph node metastases beyond the hepatoduodenal ligament are sometimes encountered in locally limited T2 gallbladder cancer (GBCA). However, the incidence and impact on prognosis remain unclear. Methods: This was a retrospective multi-institutional study of patients who underwent surgical resection for GBCA from 2002 to 2022. The eighth edition of the Union for International Cancer Control staging was used for tumor-node-metastasis categorization. The lymph node location was classified as follows: (A) along the hepatoduodenal ligament and common hepatic artery; (B) posterior side of the pancreatic head; and (C) others. Metastasis to regions A, B, and C nodes was denoted as Na, Nb, and Nc, respectively. Results: Data for 379 patients (pT1, 29; pT2, 162: pT3, 141; and pT4, 47) were evaluated; none with pT1 GBCA had node metastasis. For N1/2 GBCA, the proportion of patients with N2 disease increased with increasing T grade (p =.001), while the proportions of patients with Na, Nb, and Nc disease were comparable between pT2 (61%, 26%, and 13%), pT3 (63%, 26%, and 12%), and pT4 (50%, 38%, and 12%) disease (p =.681), respectively. Overall survival for pT2N1/2 disease (5 years, 43.8%) was comparable to that for pT3/4N0 disease (5 years, 37.2%; p =.192). Among patients with node-positive pT2 disease, overall survival was comparable for Na, Nb, and Nc disease, with 5-year survivals of 46%, 43%, and 31%, respectively (p =.346). Conclusion: Region B or C node metastasis was not rare even in pT2 GBCA. Regarding survival outcomes, pT2 node-positive GBCA should be considered advanced disease irrespective of the extent of node metastasis.

  • Clinical Impact of Neoadjuvant Therapy for Resectable Pancreatic Ductal Adenocarcinoma: A Single-Center Retrospective Study

    Shimane G., Kitago M., Yagi H., Abe Y., Hasegawa Y., Hori S., Tanaka M., Tsuzaki J., Yokoyama Y., Masugi Y., Takemura R., Kitagawa Y.

    Annals of Surgical Oncology 32 ( 4 ) 2830 - 2840 2025.04

    ISSN  10689265

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    Background: Neoadjuvant therapy is recommended for treating resectable pancreatic ductal adenocarcinoma (PDAC); however, its appropriate use in patients with resectable PDAC remains debatable. Objective: This study aimed to identify independent poor prognostic factors and evaluate the clinical significance of neoadjuvant therapy in patients with resectable PDAC. Methods: We retrospectively reviewed consecutive patients diagnosed with resectable PDAC at our institute between January 2003 and December 2022. We analyzed poor prognostic factors at the time of diagnosis in patients who underwent upfront surgery using the Cox proportional hazards model for overall survival (OS). The prognostic score was calculated by adding the individual prognostic factor scores. Results: Overall, 359 patients were included in this study, with 308 patients undergoing upfront surgery and the remaining 51 patients receiving neoadjuvant therapy. The R0 resection rate was significantly higher in the neoadjuvant therapy group (70.6%) than in the upfront surgery group (64.0%). Multivariate analysis in the upfront surgery group revealed the following independent poor prognostic factors: tumor size ≥ 35 mm, serum albumin level ≤.5 g/dL, neutrophil-to-lymphocyte ratio ≥ 3.5, carbohydrate antigen 19-9 level ≥ 250 U/mL, and Duke pancreatic monoclonal antigen type 2 level ≥ 750 U/mL. Among patients with prognostic scores of 0–1 (n = 263), the intention-to-treat OS did not significantly differ between the neoadjuvant therapy and upfront surgery groups. Among those patients with a prognostic score of ≥ 2 (n = 96), the neoadjuvant therapy group had significantly longer intention-to-treat OS than the upfront surgery group. Conclusions: Prognostic score-based stratification can help identify patients who could benefit from neoadjuvant therapy.

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