Akihito Yamamoto

Dr. Akihito Yamamoto

Depertment of Obstetrics and Gynecology, Nippon Medical School
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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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6 November 2020 in Cancers
Verified
Journal Article
Open access
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AYAkihito Yamamoto
Akihito Yamamoto
SKSeiryu Kamoi
Seiryu Kamoi
KKKeisuke Kurose
Keisuke Kurose
MIMarie Ito
Marie Ito
TTToshiyuki Takeshita
Toshiyuki Takeshita
MMMasao Miyashita
Masao Miyashita
(1) Background: Previous reports have indicated that cancers of the stomach, lung, and pancreas can be detected by dog sniffing, but results have been varied. Here, a highly trained dog was used to determine whether urine from patients with cervical premalignant lesions and malignant tumors have a cancer-specific scent. (2) Methods: A total of 195 urine samples were collected from patients with cervical cancer, cervical intraepithelial neoplasia grade 3 (CIN3), benign uterine diseases, and healthy volunteers. Each test was performed using one urine sample from a cancer patient and four samples from different controls. Each of the five urine samples was placed in a separate box. When the cancer sniffing dog stopped and sat in front of the box with a sample from a cancer patient, the test was considered as positive. (3) Results: 83 patients with cervical cancer (34 cases of cervical cancer and 49 cases of cervical intraepithelial neoplasia grade 3), 49 patients with uterine benign diseases, and 63 healthy volunteers were enrolled, and their urine samples were collected. In 83 times out of 83 runs in a double-blind test, the trained dog could correctly identify urine samples of cervical cancer patients. (4) Conclusion: A trained dog could accurately distinguish the urine of all patients with cervical cancer or CIN3, regardless of the degree of cancer progression.

16 September 2021 in International Journal of Surgery Case Reports
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Journal Article
Open access
AYAkihito Yamamoto
Akihito Yamamoto
SSShunji Suzuki
Shunji Suzuki
Introduction and importance: Uterine leiomyoma is a common disease. The tumor gradually increases and becomes a target for treatment when accompanied by certain symptoms. It rarely grows into a giant uterine leiomyoma, which is defined as leiomyoma weighing >11.34 kg. Case presentation: A 58-year-old Japanese woman had a history of putamen hemorrhage and deep vein thrombosis. A giant uterine leiomyoma prevented her from walking, and she scheduled surgery for its removal. The tumor was 46 × 35 × 27 cm, and the uterine arteries and veins were extremely dilated. A blocking balloon catheter was placed in the abdominal aorta to prevent massive bleeding, and a filter was placed in the inferior vena cava to prevent pulmonary thromboembolism. The surgery focused on careful vascular treatment, with selective ligation of the ovarian arteries and veins and the uterine arteries. The total amount of bleeding was 1130 g, and the uterus was removed without complications. The weight of the excised tissue was 22.6 kg. Clinical discussion: Surgical treatment of the largest giant uterine leiomyomas is rare and challenging. Previous reports addressed the risk of massive bleeding and perioperative death. Surgery is the best treatment for giant uterine leiomyomas, but perioperative management and surgical procedures require complex and elaborate planning. Conclusion: Very few gynecologists have experience treating giant uterine leiomyomas. Successful surgery requires careful surgical preparation, and the gynecological oncologist must have extensive experience with giant leiomyomas. Highlights:

18 December 2021 in Journal of Medical Case Reports
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Journal Article
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AYAkihito Yamamoto
Akihito Yamamoto
SKSeiryu Kamoi
Seiryu Kamoi
SSShunji Suzuki
Shunji Suzuki
Nutcracker syndrome is a condition in which the left renal vein is pinched between the abdominal aorta and the superior mesenteric artery, resulting in an increase in renal vein pressure and certain symptoms. We report a very rare case of retroperitoneal hematoma caused by the rupture of varicose veins of the left ovary. A 77-year-old Japanese woman, para 7, experienced sudden left lower abdominal pain. She had no history of trauma or treatment complications. Computed tomography revealed a left retroperitoneal hematoma, but her abdominal pain subsided quickly; thus, urgent treatment was not required. We then scheduled her for an assessment regarding the cause of her bleeding. However, 6 days after the pain onset, abdominal pain symptoms recurred, confirming hematoma regrowth. Magnetic resonance imaging and three-dimensional computed tomography revealed an abnormal vascular network from the left side of the uterus to the left adnexa. Subsequent angiography revealed that the retroperitoneal bleeding originated from rupture of the distended left ovarian vein, which caused blood reflux from the left renal vein to the left ovarian vein. Although angiography confirmed a passage between the left renal vein and inferior vena cava, computed tomography showed obvious stenosis in the left renal vein. In accordance with these findings, we diagnosed the cause of the distention and rupture of the left ovarian vein as nutcracker syndrome. She underwent embolization of the left ovarian vein as hemostasis treatment, and had a good course thereafter. This is the first report of a spontaneous rupture of the left ovarian vein caused by nutcracker syndrome. Nutcracker syndrome is not yet well known to clinicians and should be considered as part of the differential diagnosis when an abnormal vascular network in the pelvis is found.

30 March 2022 in Medicines
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Journal Article
Open access
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AYAkihito Yamamoto
Akihito Yamamoto
SKSeiryu Kamoi
Seiryu Kamoi
SMShigeru Matsuda
Shigeru Matsuda
RKRieko Kawase
Rieko Kawase
KNKazuho Nakanishi
Kazuho Nakanishi
SSShunji Suzuki
Shunji Suzuki
Background: Carboplatin, the key drug used in treating gynaecological cancer, has an approximately 12–16% risk of hypersensitivity reactions. We aimed to investigate the efficacy and adverse effects of carboplatin desensitisation therapy for gynaecological cancer. Methods: The desensitisation protocol was standardised as a four-step, 4-h, carboplatin administration in the hospital. A retrospective medical record review was conducted on 15 patients who underwent carboplatin desensitisation for gynaecological malignancies at our hospital. Patients’ data were analysed to evaluate the treatment success rate, therapeutic effect of desensitisation, adverse events, and treatment. Results: Of 91 carboplatin desensitisation cycles scheduled; the completion rate was 93.4% (85/91). Adverse events occurred in 23 of these 91 (25.3%). In four (4.4%) of the 23 cycles, hypersensitivity reactions could be treated only by discontinuing the infusion and slowing the administration, while in the remaining 19 (20.9%), medication was administered intravenously after discontinuing the infusion to manage hypersensitivity reactions. No treatment-related deaths occurred. Overall, 23 series of anti-cancer agent regimens, including carboplatin desensitisation, were administered to the 15 patients. The therapeutic response rate was 82.6% and the disease control rate was 95.7%. Conclusions: Carboplatin desensitisation was beneficial in patients with a history of carboplatin-induced hypersensitivity reactions.

11 November 2025 in Journal of Obstetrics and Gynaecology Research
Verified
Journal Article
Open access
LXLi Xiang
Li Xiang
YNYutaka Naito
Yutaka Naito
MTMasafumi Toyoshima
Masafumi Toyoshima
MTMika Terasaki
Mika Terasaki
AYAkihito Yamamoto
Akihito Yamamoto
KHKazufumi Honda
Kazufumi Honda
Objective: This study aimed to investigate the clinical significance of actinin‐4 in endometrial carcinoma. Actinin‐4, an actin‐binding protein involved in cytoskeletal dynamics, has been implicated in the progression of various cancers; however, its precise role in endometrial carcinoma is not fully understood. This research sought to evaluate actinin‐4 protein expression and gene amplification and correlate these findings with clinicopathological parameters and patient survival to determine its prognostic value. Methods: A retrospective analysis was conducted on endometrial carcinoma patients who underwent surgical resection. Actinin‐4 protein expression was assessed using immunohistochemical staining (IHC), and ACTN4 gene amplification was evaluated by fluorescence in situ hybridization (FISH). The intensity of actinin‐4 staining was graded, and gene amplification of ACTN4 was defined using the ACTN4 / CEP19 ratio. Statistical analysis, including Kaplan–Meier survival analysis and Cox proportional hazards modeling, was performed to correlate actinin‐4 expression with clinicopathological features and survival outcomes. Results: Overexpression of actinin‐4 protein by IHC was significantly associated with advanced clinical stage and histological subtypes. While no significant difference was observed in overall survival (OS), patients with high actinin‐4 IHC demonstrated significantly poorer progression‐free survival (PFS). ACTN4 gene amplification by FISH was significantly associated with poorer prognosis for both OS and PFS compared to the group without amplification. Conclusion: This study suggests that actinin‐4 plays a role in the progression of endometrial carcinoma, particularly influencing tumor aggressiveness and progression‐free survival.