Nami Ota
Wakayama Medical University
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Featured researches published by Nami Ota.
International Journal of Gynecological Cancer | 2014
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.
Molecular and Clinical Oncology | 2017
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
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.
Journal of Obstetrics and Gynaecology Research | 2018
Shoko Jitsumori; Michihisa Shiro; Fumiyoshi Kojima; Nami Ota; Sawako Minami; Kazuhiko Ino
We report a rare case of placental mesenchymal dysplasia (PMD) with fetal growth restriction (FGR) in one placenta of a dichorionic diamniotic (DD) twin pregnancy. A 24‐year‐old woman was referred to our hospital at 24 weeks’ gestation due to FGR and ipsilateral placental abnormality in DD twins. Ultrasound and magnetic resonance imaging showed one placenta of the FGR fetus was bulky and had multiple cysts, while the other fetus placenta appeared normal. Cesarean section was performed at 32 weeks’ gestation; the first and second neonates weighted 1799 and 1215 g, respectively. Macroscopically, chorionic vessels on the placental surface of the second neonate were prominently enlarged. Pathological findings demonstrated swelling stem villi with enlarged vessels and increased interstitial cells without trophoblast proliferation. Immunostaining for p57kip2 was negative in interstitial cells and cytotrophoblasts of the swelling stem villi. This suggested that PMD occurred in one placenta of the DD twin, leading to early‐onset FGR.
Case Reports in Obstetrics and Gynecology | 2017
Tomoko Noguchi; Nami Ota; Yasushi Mabuchi; Shigetaka Yagi; Sawako Minami; Hisako Okuhira; Yuki Yamamoto; Yasushi Nakamura; Kazuhiko Ino
Malignant melanoma (MM) in the female genital tract accounts for less than 2% of all melanomas, and the vast majority associated occur in the vulva and vagina. Primary MM of the uterine cervix is extremely rare and its prognosis is very poor. We report a case of primary MM of the cervix with dissemination throughout the vaginal wall. A 66-year-old woman presented with postmenopausal bleeding. Gynecologic examination demonstrated a 2 cm polypoid blackish-pigmented tumor on the cervix with multiple small blackish-pigmented lesions throughout the vaginal wall. Cervical Pap smear cytology showed malignant melanoma. MRI and PET/CT did not detect any distant or lymph node metastases. She underwent radical hysterectomy, pelvic lymphadenectomy, and total vaginectomy. The pathological diagnosis was FIGO stage IIIA primary cervical MM. She received adjuvant chemotherapy with 6 courses of dacarbazine, but 6 months later, multiple lung metastases were detected. Despite 4 courses of anti-PD-1 antibody (nivolumab) treatment, she died of the disease 13 months after surgery.
Taiwanese Journal of Obstetrics & Gynecology | 2016
Naoyuki Iwahashi; Nami Ota; Michihisa Shiro; Shigetaka Yagi; Sawako Minami; Kazuhiko Ino
OBJECTIVE Vasa previa is a rare complication, and rupture of vasa previa during pregnancy may lead to significant perinatal mortality. Here, we report a case of vasa previa evaluated prenatally using noncontrast time-of-flight magnetic resonance angiography (TOF MRA). CASE REPORT A 22-year-old primiparous woman was referred to our hospital due to suspicion of vasa previa. Transvaginal ultrasonography showed two vessels running over the internal os. To obtain further information, magnetic resonance imaging (MRI) and TOF MRA were performed. Caesarean section was carried out, and macroscopic findings of the vascular distribution on the fetal membrane were consistent with those identified by TOF MRA. CONCLUSION TOF MRA in addition to MRI may be an option for prenatal identification of the precise three-dimensional vascular distribution in patients with vasa previa.
Molecular and Clinical Oncology | 2018
Naoyuki Iwahashi; Yoko Deguchi; Yuko Horiuchi; Tomoko Noguchi; Tamaki Yahata; Nami Ota; Kazuhiko Ino; Kenichi Furukawa
Papillary thyroid carcinoma arising from ovarian mature cystic teratoma is clinically rare. We herein present a case of live birth following two laparoscopic surgeries for papillary thyroid carcinoma arising in a mature ovarian cystic teratoma. A 30-year-old female patient, gravida 1 para 1, was treated by laparoscopic bilateral ovarian cystectomy for suspicion of bilateral mature cystic teratoma. The diagnosis of papillary thyroid carcinoma arising from right ovarian mature cystic teratoma was established based on postoperative pathological examination of the tumor. Such rare neoplasms may be difficult to diagnose preoperatively based on radiological examinations alone. The patient underwent laparoscopic fertility-preserving unilateral (right) salpingo-oophorectomy. Following an extensive discussion with the patient and her family, appropriate informed consent was obtained for the treatment option and the patient and her family chose to preserve her fertility. She could have a baby following the treatment and no evidence of disease for 6 years. Gynecologists should be aware of the possibility of such rare cases, and the available surgical interventions should be fully discussed with patients who wish to preserve their fertility. Laparoscopic fertility-sparing surgery may be a feasible option when encountering such a rare condition.
Molecular and Clinical Oncology | 2016
Shigetaka Yagi; Tamaki Yahata; Yasushi Mabuchi; Yuko Tanizaki; Aya Kobayashi; Michihisa Shiro; Nami Ota; Sawako Minami; Masaki Terada; Kazuhiko Ino
Molecular and Clinical Oncology | 2016
Tamaki Yahata; Shigetaka Yagi; Yasushi Mabuchi; Yuko Tanizaki; Aya Kobayashi; Madoka Yamamoto; Mika Mizoguchi; Sakiko Nanjo; Michihisa Shiro; Nami Ota; Sawako Minami; Masaki Terada; Kazuhiko Ino
日本産科婦人科學會雜誌 | 2016
Tomoko Noguchi; Michihisa Shiro; Naoyuki Iwahashi; Sakiko Nanjo; Madoka Yamamoto; Nami Ota; Yasushi Mabuchi; Shigetaka Yagi; Sawako Minami; Kazuhiko Ino