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Featured researches published by Yasushi Mabuchi.


Obstetrics & Gynecology | 2002

Postmenopausal intravenous leiomyomatosis with high levels of estradiol and estrogen receptor.

Katsuji Kokawa; Mareo Yamoto; Chie Yata; Yasushi Mabuchi; Naohiko Umesaki

BACKGROUND Intravenous leiomyomatosis is a rare variant of leiomyoma. CASE The patient was a 49-year-old gravida 3, para 3 woman with menopause at age 46. She presented with a history of syncope. Vaginal examination revealed an enlarged and elastic-soft mass of the uterus. A pelvic ultrasound, computed tomography scan, and magnetic resonance imaging showed a heterogeneous, irregularly shaped 8- to 10-cm tumor. In addition, the inferior vena cava was almost completely occluded. Cardiac ultrasound demonstrated a mobile mass in the right atrium. The serum estradiol was 208 pg/mL (normal 0–59). Intravenous leiomyomatosis with cardiac extension was diagnosed preoperatively. A resection of the intracardiac and intracaval mass and a subtotal hysterectomy with bilateral salpingo-oophorectomy were performed. The uterine tumor weighed 600 g, and the cordlike intravascular tumor extending from the internal iliac vein into the right ventricle was 40 cm long and weighed 60 g. Pathologic examination confirmed intravenous leiomyomatosis with no evidence of atypia. The level of estrogen receptor in the tissue was 140 fmol/mg protein. The postoperative course was uneventful, and she has been in good health for 17 months after the operation. CONCLUSION We report a case of intravenous leiomyomatosis extending into the right ventricle treated with a one-stage operation. It is possible that a high concentration of serum estradiol and high level of tissue estrogen receptor are related to the intravenous leiomyomatosis.


International Journal of Gynecological Cancer | 2014

Diagnostic value of preoperative SUVmax on FDG-PET/CT for the detection of ovarian cancer.

Yuko Tanizaki; Aya Kobayashi; Michihisa Shiro; Nami Ota; Rei Takano; Yasushi Mabuchi; Shigetaka Yagi; Sawako Minami; Masaki Terada; Kazuhiko Ino

Objective The objective of this study was to investigate the preoperative diagnostic value of 18F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography and computed tomography (PET/CT) in patients with ovarian cancer. Methods One hundred sixty patients suspected of having malignant ovarian tumors were included in this study. All patients underwent FDG-PET/CT scans before operation, and the maximum standardized uptake value (SUVmax) of the primary tumor was measured. We evaluated the diagnostic accuracy of SUVmax for detecting malignancy and its relationship with histological findings. Results Postoperative pathological diagnoses showed that 67 were malignant, 14 were borderline malignant, and 79 were benign tumors. With the use of a cutoff SUVmax of 2.9 obtained from the receiver operating characteristic curve analysis, the sensitivity, specificity, positive predictive value, and negative predictive value for detecting malignancy were 80.6%, 94.6%, 91.5%, and 87.1%, respectively. Positive FDG accumulation (SUVmax ≥ 2.9) was shown in 89.5% of serous adenocarcinoma and in 92.3% of endometrioid adenocarcinoma. In contrast, lower frequencies of positive FDG accumulation were shown in clear cell adenocarcinoma (54.5%), mucinous adenocarcinoma (66.7%), and metastatic carcinoma (66.7%), and the median SUVmax of these 3 histological types were significantly lower than those of serous and endometrioid types. In addition, a positive FDG accumulation was shown in all patients with malignant transformation of mature cystic teratoma. Finally, of the 14 borderline malignant tumors, only 2 (14.3%) showed positive FDG accumulation. Conclusions The SUVmax on FDG-PET/CT is useful for differentiating ovarian cancer from borderline or benign tumor with a high specificity and positive predictive value. However, our data also demonstrated a lower FDG uptake value in clear cell or mucinous histological finding, suggesting that SUVmax may vary depending on the tumor histological subtype.Objective The objective of this study was to investigate the preoperative diagnostic value of 18F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography and computed tomography (PET/CT) in patients with ovarian cancer. Methods One hundred sixty patients suspected of having malignant ovarian tumors were included in this study. All patients underwent FDG-PET/CT scans before operation, and the maximum standardized uptake value (SUVmax) of the primary tumor was measured. We evaluated the diagnostic accuracy of SUVmax for detecting malignancy and its relationship with histological findings. Results Postoperative pathological diagnoses showed that 67 were malignant, 14 were borderline malignant, and 79 were benign tumors. With the use of a cutoff SUVmax of 2.9 obtained from the receiver operating characteristic curve analysis, the sensitivity, specificity, positive predictive value, and negative predictive value for detecting malignancy were 80.6%, 94.6%, 91.5%, and 87.1%, respectively. Positive FDG accumulation (SUVmax ≥ 2.9) was shown in 89.5% of serous adenocarcinoma and in 92.3% of endometrioid adenocarcinoma. In contrast, lower frequencies of positive FDG accumulation were shown in clear cell adenocarcinoma (54.5%), mucinous adenocarcinoma (66.7%), and metastatic carcinoma (66.7%), and the median SUVmax of these 3 histological types were significantly lower than those of serous and endometrioid types. In addition, a positive FDG accumulation was shown in all patients with malignant transformation of mature cystic teratoma. Finally, of the 14 borderline malignant tumors, only 2 (14.3%) showed positive FDG accumulation. Conclusions The SUVmax on FDG-PET/CT is useful for differentiating ovarian cancer from borderline or benign tumor with a high specificity and positive predictive value. However, our data also demonstrated a lower FDG uptake value in clear cell or mucinous histological finding, suggesting that SUVmax may vary depending on the tumor histological subtype.


Cancer Science | 2014

Indoleamine 2,3-dioxygenase promotes peritoneal metastasis of ovarian cancer by inducing an immunosuppressive environment.

Yuko Tanizaki; Aya Kobayashi; Saori Toujima; Michihisa Shiro; Mika Mizoguchi; Yasushi Mabuchi; Shigetaka Yagi; Sawako Minami; Osamu Takikawa; Kazuhiko Ino

Indoleamine 2,3‐dioxygenase (IDO) is a tryptophan‐catabolizing enzyme that has immunoregulatory functions. Our prior study showed that tumoral IDO overexpression is involved in disease progression and impaired patient survival in human ovarian cancer, although its mechanism remains unclear. The purpose of the present study is to clarify the role of IDO during the process of peritoneal dissemination of ovarian cancer. Indoleamine 2,3‐dioxygenase cDNA was transfected into the murine ovarian carcinoma cell line OV2944‐HM‐1, establishing stable clones of IDO‐overexpressing cells (HM‐1‐IDO). Then HM‐1‐IDO or control vector‐transfected cells (HM‐1‐mock) were i.p. transplanted into syngeneic immunocompetent mice. The HM‐1‐IDO‐transplanted mice showed significantly shortened survival compared with HM‐1‐mock‐transplanted (control) mice. On days 11 and 14 following transplantation, the tumor weight of peritoneal dissemination and ascites volume were significantly increased in HM‐1‐IDO‐transplanted mice compared with those of control mice. This tumor‐progressive effect was coincident with significantly reduced numbers of CD8+ T cells and natural killer cells within tumors as well as increased levels of transforming growth factor‐β and interleukin‐10 in ascites. Finally, treatment with the IDO inhibitor 1‐methyl‐tryptophan significantly suppressed tumor dissemination and ascites with reduced transforming growth factor‐β secretion. These findings showed that tumor‐derived IDO promotes the peritoneal dissemination of ovarian cancer through suppression of tumor‐infiltrating effector T cell and natural killer cell recruitment and reciprocal enhancement of immunosuppressive cytokines in ascites, creating an immunotolerogenic environment within the peritoneal cavity. Therefore, IDO may be a promising molecular target for the therapeutic strategy of ovarian cancer.


Current Cancer Drug Targets | 2011

Role of the renin-angiotensin system in gynecologic cancers.

Kazuhiko Ino; Kiyosumi Shibata; Eiko Yamamoto; Hiroaki Kajiyama; Akihiro Nawa; Yasushi Mabuchi; Shigetaka Yagi; Sawako Minami; Yuko Tanizaki; Aya Kobayashi; Fumitaka Kikkawa

Recent studies have shown an activation of the local renin-angiotensin system (RAS) in various tumor tissues, including the abundant generation of angiotensin II (Ang II) by angiotensin-converting enzyme (ACE) and the upregulation of angiotensin II type 1 receptor (AT1R) expression. Thus, considerable attention has been paid not only to the role of the RAS in cancer progression, but also to the blockade of RAS as a new approach to the treatment of human cancer. There is increasing evidence that the Ang II-AT1R pathway is involved in tumor growth, angiogenesis and metastasis in various experimental animal models, suggesting the therapeutic potential of an ACE inhibitor and AT1R blocker. In addition, specific Ang II-degrading enzymes are also expressed in tumors and play a regulatory role in tumor cell proliferation and invasion. This review focuses on the role of the RAS in the progression of gynecologic cancers, such as cervical cancer, endometrial cancer, ovarian cancer, and gestational choriocarcinoma. We present here the clinical potential of blocking the RAS as a novel and promising strategy for the treatment of gynecologic cancers.


Journal of Clinical Pathology | 2012

Clinicopathological significance of podocalyxin and phosphorylated ezrin in uterine endometrioid adenocarcinoma

Hironao Yasuoka; Masahiko Tsujimoto; Michiya Inagaki; Rieko Kodama; Hiromi Tsuji; Yoshifumi Iwahashi; Yasushi Mabuchi; Kazuhiko Ino; Tokio Sanke; Yasushi Nakamura

Background Podocalyxin is an anti-adhesive glycoprotein that has been associated with highly aggressive forms of cancers. Podocalyxin increases the migration and invasive properties of cancer cells through its interaction with ezrin, which undergoes an increase in phosphorylation through podocalyxin. Aims To study the roles of podocalyxin and phosphorylated ezrin (pEzrin) in uterine endometrioid adenocarcinoma (UEA). Methods Using immunohistochemisty the authors investigated the expression of podocalyxin and pEzrin along with some well-known markers of tumour aggressiveness including p53, oestrogen receptor and Ki-67 in UEA. Results Podocalyxin and pEzrin expression levels were positive in 36.1% (22 of 61 patients) and 50.8% (31 of 61 patients) of UEA cases, respectively. Further, podocalyxin expression was correlated with tumour grade (p=0.0001), FIGO stage (p=0.0062), p53 expression (p=0.0050) and Ki-67 index (p=0.0069). In addition, pEzrin expression was associated with FIGO stage (p=0.0231), p53 expression (p<0.0001) and Ki-67 index (p=0.0010). The expression of podocalyxin was also correlated with that of pEzrin (p=0.0102). Conclusions These results suggest that overexpression of podocalyxin and pEzrin may indicate a more aggressive phenotype; thus, evaluation of these proteins may be useful in prediction of disease progression in UEA cases.


Journal of Clinical Ultrasound | 2010

Two cases of vasa previa diagnosed prenatally using three-dimensional ultrasonography.

Yasushi Mabuchi; Mareo Yamoto; Sawako Minami; Eiji Boshi; Shigetaka Yagi; Nami Oba; Kazuharu Tanaka; Naohiko Umesaki

We report two cases in which we describe the impact of sonography (US) in the management of vasa previa. In the first case, with two‐dimensional US, the diagnosis of vasa previa was made at 21 weeks gestation. In the second case, using three‐dimensional US, the diagnosis of vasa previa was made at 19 weeks gestation. An elective Cesarean section was carried out at 34 weeks in both cases. Diagnosis of vasa previa is critical when low‐lying placenta or velamentous insertion of the umbilical cord is detected during the pregnancy.


Journal of Radiation Research | 2012

Percutaneous interstitial brachytherapy for adrenal metastasis: technical report

Kazushi Kishi; Shinji Tamura; Yasushi Mabuchi; Tetsuo Sonomura; Yasutaka Noda; Motoki Nakai; Morio Sato; Kazuhiko Ino; Noboru Yamanaka

We developed and evaluated the feasibility of a brachytherapy technique as a safe and effective treatment for adrenal metastasis. Adapting a paravertebral insertion technique in radiofrequency ablation of adrenal tumors, we developed an interstitial brachytherapy for adrenal metastasis achievable on an outpatient basis. Under local anesthesia and under X-ray CT guidance, brachytherapy applicator needles were percutaneously inserted into the target. A treatment plan was created to eradicate the tumor while preserving normal organs including the spinal cord and kidney. We applied this interstitial brachytherapy technique to two patients: one who developed adrenal metastasis as the third recurrence of uterine cervical cancer after reirradiation, and one who developed metachronous multiple metastases from malignant melanoma. The whole procedure was completed in 2.5 hours. There were no procedure-related or radiation-related early/late complications. FDG PET-CT images at two and three months after treatment showed absence of FDG uptake, and no recurrence of the adrenal tumor was observed for over seven months until expiration, and for six months until the present, respectively. This interventional interstitial brachytherapy procedure may be useful as a safe and eradicative treatment for adrenal metastasis.


Journal of Radiation Research | 2012

Eradicative brachytherapy with hyaluronate gel injection into pararectal space in treatment of bulky vaginal stump recurrence of uterine cancer

Kazushi Kishi; Yasushi Mabuchi; Tetsuo Sonomura; Shintaro Shirai; Yasutaka Noda; Morio Sato; Kazuhiko Ino

The purpose of this study is to develop a procedure for eradicative brachytherapy that can deliver a curative boost dose to bulky (>4 cm) vaginal stump recurrence of uterine cancer without risk of damaging surrounding organs. We separated risk organs (the rectum and sigmoid) from the target during brachytherapy, with a hyaluronate gel injection into the pararectal space via the percutaneous paraperineal approach under local anesthesia. The rectum anchored to the sacrum by native ligament was expected to shift posteriorly. We encountered a patient with bulky stump recurrence of uterine cancer, approximately 8 cm in maximum diameter. She was complaining of abdominal pain and constipation due to bowel encasement. Following 50 Gy of external beam radiotherapy, we applied a single fraction of brachytherapy under gel separation and delivered 14.5 Gy (50.8 GyE: equivalent dose in 2-Gy fraction calculated with linear quadratic model at α/β = 3) to the target. The gel injection procedure was completed in 30 min without complications. A total irradiation dose of 100.8 GyE was delivered to the target and the cumulative minimum dose to the most irradiated rectosigmoidal volume of 2 cc (cumulative D2cc) was calculated as 58.5 GyE with gel injection, and was estimated to be 96 GyE without. Over three years, the local stump tumor has completely disappeared, with no complications. Brachytherapy with a pararectal gel injection can be a safe and effective eradicative option for bulky vaginal stump recurrence.


Molecular and Clinical Oncology | 2017

Identical twins with mature cystic teratomas treated with laparoscopic surgery: Two case reports

Yasushi Mabuchi; Nami Ota; Aya Kobayashi; Yuko Tanizaki; Sawako Minami; Kazuhiko Ino

Mature cystic teratomas are the most common among all ovarian neoplasms, representing 30-40% of the cases. However, to the best of our knowledge, there have been only two reports of mature cystic teratomas occurring in identical twins to date. We herein report a case of identical twins with mature cystic teratomas who were treated with laparoscopic surgery. A 32-year-old woman was referred to our hospital due to a tumor in the right ovary. The patient underwent laparoscopic resection of the ovarian tumor and the pathological diagnosis was benign mature cystic teratoma. Two years later, the identical twin of the abovementioned patient was referred to our hospital also due to a right ovarian tumor. The patient underwent laparoscopic resection of the ovarian tumor and the pathological diagnosis was benign mature cystic teratoma. Therefore, for early diagnosis, it may be important to consider the possibility of mature cystic teratoma in the identical twin of a patient, even in the absence of symptoms.


International Journal of Gynecological Cancer | 2015

Clinicopathologic Factors of Cervical Adenocarcinoma Stages IB to IIB.

Yasushi Mabuchi; Tamaki Yahata; Aya Kobayashi; Yuko Tanizaki; Michihisa Shiro; Nami Ota; Shigetaka Yagi; Sawako Minami; Kazuhiko Ino

Objective The aim of this study was to clarify the clinicopathologic factors of stages IB to IIB cervical adenocarcinoma. Methods Several clinicopathologic factors were compared between 35 patients who underwent radical hysterectomy and pelvic lymphadenectomy due to cervical adenocarcinoma stages IB to IIB and 77 patients with squamous cell carcinoma (SCC). Results In patients with adenocarcinoma, univariate analysis demonstrated that International Federation of Gynecology and Obstetrics stage, tumor size, and lymphovascular space invasion were significantly associated with progression-free survival (PFS), whereas FIGO stage, lymphovascular space invasion, and lymph node metastasis were significantly associated with overall survival (OS). However, multivariate analysis revealed that FIGO stage was the only significant factor for PFS in patients with adenocarcinoma. In patients with SCC, univariate analysis demonstrated that FIGO stage and lymph node metastasis were significantly associated with PFS, whereas FIGO stage, lymphovascular space invasion, and lymph node metastasis were significantly associated with OS. Multivariate analysis revealed that lymph node metastasis was the only significant factor for PFS and OS in patients with SCC. In 26 patients who were positive for high-risk human papillomavirus (HPV), including both adenocarcinoma and SCC patients, univariate and multivariate analyses revealed that HPV18 was significantly associated with poorer PFS compared with non-HPV18. There was a significant difference in distribution of HPV genotype between adenocarcinoma and SCC. Conclusions Careful treatment may be necessary for the patients with lymphovascular space invasion in early-stage cervical adenocarcinoma. The presence of HPV18 may have an influence on the prognosis of early-stage cervical carcinoma.

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Kazuhiko Ino

Wakayama Medical University

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Sawako Minami

Wakayama Medical University

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Shigetaka Yagi

Wakayama Medical University

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Nami Ota

Wakayama Medical University

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Michihisa Shiro

Wakayama Medical University

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Aya Kobayashi

Wakayama Medical University

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Yuko Tanizaki

Wakayama Medical University

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Madoka Yamamoto

Wakayama Medical University

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Naoyuki Iwahashi

Wakayama Medical University

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Tamaki Yahata

Wakayama Medical University

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