Hiroyuki Takahashi

Dr. Hiroyuki Takahashi

Division of HBP and Transplant Surgery, Department of Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan

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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28 August 2025 in Cancers
Verified
Journal Article
Open access
PDF file
HYHIDEKI YOKOO
HIDEKI YOKOO
SMShoichiro Mizukami
Shoichiro Mizukami
HTHiroyuki Takahashi
Hiroyuki Takahashi
TTTomoki Takizawa
Tomoki Takizawa
KEKatsuro Enomoto
Katsuro Enomoto
KIKoji Imai
Koji Imai
Background: Hepatocellular carcinoma (HCC) larger than 10 cm has a poor prognosis, with high recurrence rates, particularly distant metastases. This study examined whether lenvatinib treatment followed by liver resection improves the outcomes for large HCCs compared with upfront surgery. Methods: We retrospectively analyzed 30 patients with HCC larger than 10 cm who underwent hepatectomy at our institution between January 2008 and December 2023. The study cohort included 30 patients: 9 received preoperative lenvatinib treatment followed by hepatectomy (LEN group), while 21 patients underwent upfront surgery (UFS group). We compared the clinicopathological characteristics, surgical outcomes, recurrence patterns, and survival between the two groups. Results: The median duration of lenvatinib administration was 1.8 months, with partial response in two patients (22.2%) and stable disease in seven patients (77.7%). While lenvatinib treatment significantly decreased serum albumin levels (p < 0.05) and increased ALBI scores (p = 0.03), the surgical outcomes including blood loss, operation time, and complication rates were comparable between the two groups. The 3-year recurrence-free survival rate was significantly higher in the LEN group compared with the UFS group (66.7% vs. 16.1%, p = 0.027). The 3-year overall survival rate was also higher in the LEN group, though not statistically significant (85.7% vs. 56.1%, p = 0.059). Notably, distant metastasis rates were lower in the LEN group compared with the UFS group (11.1% vs. 47.6%, p = 0.10). Conclusions: Preoperative lenvatinib treatment followed by hepatectomy for large HCC (> 10 cm) may reduce recurrence, particularly distant metastases, and potentially improve long-term survival. This approach may be a promising strategy for large HCCs, which traditionally have a poor prognosis with upfront surgery alone.

29 December 2023 in Current Oncology
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Journal Article
Open access
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RSRyotaro Shimazaki
Ryotaro Shimazaki
MHMasahiro Hagiwara
Masahiro Hagiwara
CTChikayoshi Tani
Chikayoshi Tani
HIHiroyoshi Iwata
Hiroyoshi Iwata
HTHiroyuki Takahashi
Hiroyuki Takahashi
HYHIDEKI YOKOO
HIDEKI YOKOO
Anorectal malignant melanoma (ARMM) is extremely rare and generally lethal, irrespective of the treatment administered. The disease is often diagnosed late, metastases being present in approximately two-thirds of patients at the time of initial diagnosis. Solitary metastasis of ARMM to a distant organ is exceedingly rare. A 76-year-old woman with a history of laparoscopic abdominoperineal resection of an ARMM 13 months previously, was found to have a solitary liver metastasis in the follow-up computed tomography. A preoperative work-up showed no other distant metastases nor contraindication to surgery. It was therefore considered that resection was indicated. The metachronous solitary liver metastasis from an ARMM was treated by laparoscopic wedge hepatectomy of the eighth segment 18 months after excision of her primary ARMM. Adjuvant therapy with pembrolizumab was initiated and continued at 6-week intervals. The patient has not exhibited any immune related Adverse Effects (irAE) during or subsequent to treatment with pembrolizmab and has now completed 12 months of adjuvant pembrolizumab therapy, having survived 33 months from the initial operation for primary ARMM, and remaining recurrence-free 14 months after hepatectomy. ARMM is extremely rare and resection of a metachronous solitary metastasis followed by adjuvant therapy has not previously been reported. We hope this case will be useful for clinicians who might treat similar patients.

9 June 2023 in Preprints.org
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Preprint
Open access
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YAYuki Adachi
Yuki Adachi
HTHiroyuki Takahashi
Hiroyuki Takahashi
TYTomohiro Yamamoto
Tomohiro Yamamoto
MHMasahiro Hagiwara
Masahiro Hagiwara
KIKoji Imai
Koji Imai
HYHIDEKI YOKOO
HIDEKI YOKOO
Right-sided ligamentum teres (RSLT) is a rare anatomic variant in which the fetal umbilical vein connects to the right portal vein. Patients with RSLT frequently have hepatic vasculature and bile duct anomalies, which increase the risk of complications with hepatectomy. Most patients with RSLT undergo open hepatectomy. We describe a patient with RSLT and hepatocellular carcinoma who underwent laparoscopic hepatectomy. The patient was a 69-year-old man with hepatocellular carcinoma located in the left liver based on computed tomography (CT) and magnetic resonance imaging. Imaging also demonstrated RSLT. Three-dimensional CT analysis revealed independent right lateral type anomalies of the portal vein and bile duct. Laparoscopic extended left lateral sectionectomy was performed after careful surgical planning. Ultrasonography was used frequently during surgery to avoid damaging the right hepatic vasculature. The left lateral and partial left median sections were removed as planned. The patient’s postoperative recovery was uneventful. Avoiding injury to the right hepatic vasculature is essential when performing left lobectomy, including left lateral sectionectomy, in patients with RSLT. Laparoscopic hepatectomy can be performed safely in patients with RSLT, provided that careful surgical planning is conducted using preoperative three-dimensional CT analysis and intraoperative ultrasonography is used.

16 July 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
HTHiroyuki Takahashi
Hiroyuki Takahashi
SMShoichiro Mizukami
Shoichiro Mizukami
TTTomoki Takizawa
Tomoki Takizawa
KMKai Makino
Kai Makino
YAYuki Adachi
Yuki Adachi
HYHIDEKI YOKOO
HIDEKI YOKOO
Background/Objectives: A postoperative recovery capacity-enhancement program, Enhanced Recovery After Surgery (ERAS), has recently been developed according to evidence regarding perioperative management, recognizing the importance of perioperative rehabilitation. We examined the effectiveness of perioperative rehabilitation in patients with sarcopenia undergoing hepato-biliary-pancreatic (HBP) surgery. Methods: We evaluated 155 patients who underwent high-level HBP surgery from August 2017 to December 2019. We recorded their preoperative nutritional index (prognostic nutritional index and controlling nutritional status (CONUT) score), skeletal muscle index (SMI), surgical operation, and postoperative course. SMI was measured by bioimpedance analysis using an InBody S10®. Results: We analyzed data for 155 patients, including 68 in the sarcopenia (S) group and 87 in the non-sarcopenia (NS) group, according to the Asian Working Group for Sarcopenia criteria. The CONUT score was significantly higher and the nutritional status was poorer in the S group than in the NS group. The number of diabetic cases was also significantly higher in the S group than in the NS group. There was no significant difference in serious postoperative complications (Clavien–Dindo grade ≥ IIIa) between the groups, including pleural effusion and ascites that was difficult to treat. There was also no significant difference in length of hospital stay between the two groups. Conclusions: Among patients undergoing HBP surgery, patients with sarcopenia are likely to have poorer nutritional status and SMI; however, perioperative rehabilitation may help to avoid serious postoperative complications and long-term hospitalization after surgery.

24 September 2026 in Nutrients
Verified
Journal Article
Open access
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YAYuki Adachi
Yuki Adachi
SSShingo Shimada
Shingo Shimada
SMShoichiro Mizukami
Shoichiro Mizukami
TTTomoki Takizawa
Tomoki Takizawa
KEKatsuro Enomoto
Katsuro Enomoto
HYHIDEKI YOKOO
HIDEKI YOKOO
Background/Objectives: The impact of preoperative zinc (Zn) status on the survival and recurrence of patients with hepatocellular carcinoma (HCC) after hepatectomy remains unclear. This study aimed to clarify whether preoperative Zn deficiency affects the prognosis of patients with HCC undergoing initial curative hepatectomy. Methods: We retrospectively reviewed 105 patients who underwent initial curative hepatectomy for HCC at our institution (2011–2018). Preoperative Zn deficiency was defined as serum Zn < 70 µg/dL. Clinical and tumor parameters were compared between patients with and without Zn deficiency. Disease-free and overall survival were evaluated using the Kaplan–Meier method, and prognostic factors were identified via univariate and multivariate Cox proportional hazards analyses. Subgroup analyses were conducted based on age, gender, and etiology. Results: Among 105 patients, 46 (43.8%) showed Zn deficiency (Zn deficiency group), whereas 59 (56.2%) showed normal Zn (normal Zn group). Compared with the normal-Zn group, the Zn deficiency group showed significantly lower hemoglobin, prothrombin activity, serum albumin, and smaller tumor size (all p < 0.05). The Zn deficiency group experienced significantly worse disease-free survival (p = 0.015) but no difference in overall survival (p = 0.63). On multivariate analysis, zinc deficiency (hazard ratio [HR] 1.83, p = 0.040) and prothrombin activity (HR 0.98, p = 0.042) were independent predictors of worse disease-free survival. Subgroup analysis revealed that Zn deficiency was significantly associated with elevated recurrence risk in patients with HCV-related liver disease (HR 3.67, p = 0.013). Conclusions: Preoperative Zn deficiency is an independent predictor of worse DFS after curative hepatectomy. Although further large-scale studies are required to confirm these findings, evaluating preoperative Zn status may help identify patients at high risk of HCC recurrence.

23 September 2026 in Preprints.org
Verified
Preprint
Open access
PDF file
HYHIDEKI YOKOO
HIDEKI YOKOO
SMShoichiro Mizukami
Shoichiro Mizukami
HTHiroyuki Takahashi
Hiroyuki Takahashi
KEKatsuro Enomoto
Katsuro Enomoto
TTTomoki Takizawa
Tomoki Takizawa
KIKoji Imai
Koji Imai
Background/Objectives : Hepatocellular carcinoma ³ 10 cm has a poor prognosis after surgical resection, largely because of extrahepatic recurrence. Neoadjuvant systemic therapy may improve long-term outcomes. We evaluated neoadjuvant systemic therapy followed by hepatectomy versus upfront surgery for large hepatocellular carcinoma. Methods: We retrospectively analyzed the data of 38 consecutive patients with hepatocellular carcinoma ³ 10 cm who underwent hepatectomy between April 2011 and October 2025. The patients were divided into neoadjuvant systemic therapy (n = 17; atezolizumab plus bevacizumab, n = 8; lenvatinib, n = 9) and upfront surgery (n = 21) groups. Clinicopathological features, perioperative outcomes, recurrence-free survival, and overall survival were compared. Tumor response was assessed using Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and modified RECIST. Results: Baseline characteristics were summarized. Perioperative outcomes, including blood loss, operative time, and morbidity, were similar. The systemic therapy group showed higher 5-year recurrence-free survival (45.2% vs. 16.1%, p = 0.016) and overall survival (75.8% vs. 30.6%, p = 0.037) rates than the upfront surgery group. Overall recurrence was lower in the systemic therapy group (35.3% vs. 90.5%, p < 0.001). Extrahepatic recurrence alone occurred in 42.9% of upfront surgery patients versus none in the systemic therapy group. Descriptive analyses suggested differences in tumor marker and radiological responses between the Atezolizumab plus bevacizumab and lenvatinib subgroups, while overall oncological outcomes were comparable. Liver function remained within acceptable ranges during systemic therapy. Conclusions: Neoadjuvant systemic therapy followed by hepatectomy for hepatocellular carcinoma ≥10 cm was associated with favorable recurrence and survival outcomes compared with historical upfront surgery cases, without an apparent increase in perioperative risk.