Nobuaki Kosaka
Dokkyo Medical University
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Featured researches published by Nobuaki Kosaka.
Journal of Medical Case Reports | 2016
Emi Motegi; Kiyoshi Hasegawa; Satoshi Kawai; Kaori Kiuchi; Nobuaki Kosaka; Yoshiko Mochizuki; Ichio Fukasawa
BackgroundSeveral approaches for treating severe uterine cervical stenosis after conization for cervical intraepithelial neoplasia have been reported; yet, the condition can still be difficult to treat successfully.Case presentationWe performed uterine cervical dilation surgery in two patients with severe stenosis, followed by insertion of the levonorgestrel-releasing intrauterine system, which is used for dysmenorrhea or endometriosis-related pain because of its strong progesterone activity. Patient 1 was a 34-year-old Japanese woman who was diagnosed with dysmenorrhea caused by recurrent uterine cervical stenosis and hematometra after laser conization. Patient 2 was a 44-year-old Japanese woman who developed dysmenorrhea and prolonged menstruation caused by uterine cervical stenosis without hematometra. After providing informed consent, they underwent cervical dilation surgery followed by insertion of the levonorgestrel-releasing intrauterine system. After treatment, their symptoms immediately improved, and after removal of their devices, they remained asymptomatic.ConclusionsTo the best of our knowledge, this is the first report to confirm the usefulness and easy applicability of the levonorgestrel-releasing intrauterine system for uterine cervical stenosis. Although we had success with the method, this study of two patients is preliminary. Further study with larger numbers of patients is necessary to confirm the usefulness of our technique.
Acta Cytologica | 2017
Nobuaki Kosaka; Kiyoshi Hasegawa; Kaori Kiuchi; Shoko Ochiai; Tamiko Nagai; Hiromi Machida; Ichio Fukasawa
Background: Ovarian steroid cell tumors (SCTs) are rare and usually benign, although 25-43% are reportedly malignant. The cytologic findings of these rare ovarian tumors have almost never been reported. Case: We report a rare case of a malignant ovarian SCT with peritoneal dissemination and malignant ascites in a 40-year-old woman. Her tumor was classified as stage IIB (pT2bNoM0) according to the FIGO (International Federation of Gynecology and Obstetrics) classification system, and she was treated with adjuvant chemotherapy following staging laparotomy. Cytology of the ascitic fluid revealed large, polygonal-to-round cells and multinucleated cells with atypia, appearing in clusters with slight overlapping or as isolated tumor cells. Numerous tumor cells had small central round or eccentric nuclei with conspicuous nucleoli, and a moderate-to-abundant amount of cytoplasm, varying from granular and eosinophilic to pale and multivacuolated (foamy), with cannibalism formations. The nuclear chromatin was fine and granular, with irregular distribution and nuclear-membrane thickening. Conclusion: These may be the first reported cytology results for ascites with a malignant SCT. Our patients cytological ascitic findings, rather than the histopathologic features of the original and disseminated tumors, represent the malignant features of the tumor.
Journal of Obstetrics and Gynaecology Research | 2016
Kaori Kiuchi; Kiyoshi Hasegawa; Tatsuko Nagai; Mariko Watanabe; Nobuaki Kosaka; Hiromi Machida; Ichio Fukasawa
Ectopic ovary, a designation that includes supernumerary ovaries and accessory ovaries, is a rare gonadal anomaly. We encountered a patient with a metastasis to such an anomaly and herein provide a review of the published work. A 43‐year‐old woman was diagnosed with stage IIb cervical adenocarcinoma with suspicion for a right ovarian malignancy. She underwent laparotomy after completing three cycles of neoadjuvant chemotherapy. Intraoperative inspection revealed two normal ovaries, but an ovary‐like structure was identified attached to the fimbriae of the left fallopian tube. A cystic tumor, 12 cm in diameter, developed from this structure, which was not connected to the infundibulopelvic ligament. The mass was pulled and elevated into the right pelvis by omental adhesions. Pathological examination revealed uterine cervical endometrioid adenocarcinoma with deep stromal invasion, vaginal invasion, and pelvic lymph‐node metastases. Both the left eutopic ovary and the ovary‐like structure contained endometrioid adenocarcinoma metastases. The ovary‐like structure contained spindle‐shaped theca cells, which were positive for inhibin α; therefore, this structure was defined as ovarian tissue. The final diagnosis was well‐differentiated uterine cervical endometrioid adenocarcinoma with metastases to the pelvic lymph nodes and to the left eutopic and ectopic ovaries (pT2a2N1M0). To the best of our knowledge, there have been no previous descriptions in the English‐language published work of uterine cervical adenocarcinoma metastasizing concurrently to unilateral eutopic and ectopic ovaries.
Rare Tumors | 2009
Masaru Hayashi; Shigeki Tomita; Takahiro Fujimori; Hitoshi Nagata; Keiichi Kubota; Akiko Shoda; Kazumi Tada; Nobuaki Kosaka; Ichio Fukasawa; Noriyuki Inaba
Retrorectal epidermoid cyst is one of the developmental cysts which arise from remnants of embryonic tissues. We report a rare case of retrorectal epidermoid cyst, initially diagnosed as an ovarian tumor. Serum SCC value as tumor marker was elevated to the high level. Laparoscopy revealed ovaries, uterus and other pelvic organs were all normal. This tumor existed in the retroperitoneal cavity and compressed the rectum. Later, complete tumor resection was performed by laparotomy. Histological study revealed the epithelium of this tumor consisted of only squamous cells without atypia, and the diagnosis of this tumor was retrorectal epidermoid cyst. Retrorectal epidermoid cyst is very rare, and difficult to diagnose before surgery. However, if we have-knowledge of developmental cysts, and by careful digital examination and image diagnosis, a differential diagnosis can be made.
Journal of Obstetrics and Gynaecology | 2018
Kaori Kiuchi; Kiyoshi Hasegawa; Shoko Ochiai; Emi Motegi; Tatsuya Kuno; Nobuaki Kosaka; Ichio Fukasawa
Abstract Recently, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) or prognostic nutritional index (PNI) have been investigated as prognostic parameters in various malignancies. Herein, we detail how we have investigated the prognostic significance of NLR, PLR and PNI together with the other clinicopathological factors for International Federation of Gynaecology and Obstetrics stage IVB endometrial carcinoma. Thirty-two patients with clinical stage IVB disease were enrolled. The relationship between clinicopathological factors, NLR, PLR or PNI and overall survival (OS) rates was investigated. The 5-year OS rate was 9.7%, and the median survival time was 9 months. In univariate analysis, PS 0–1, G1–2 endometrioid carcinoma, occurrence of surgery, NLR (below median) and PNI (≥median) were identified as favourable prognostic factors. In multivariate analysis, only a histology (G1–2 endometrioid carcinoma) was identified as an independent favourable prognostic factor. Additional large-scale studies are required to confirm the prognostic significance of NLR, PLR and PNI in clinical stage IVB endometrial carcinoma. Impact Statement What is already known on this subject? Several parameters representing the systemic inflammatory response (e.g. neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR)) or the nutritional condition (e.g. prognostic nutritional index (PNI)) have been investigated as prognostic parameters in various malignancies, whereas they have not been thoroughly investigated in endometrial carcinoma. What the results of this study add? In univariate analysis of various factors for overall survival, the performance status (PS) 0–1, grade 1–2 endometrioid carcinoma, occurrence of surgery, NLR (below median) and PNI (≥median) were identified as favourable prognostic factors. However, in a multivariate analysis, only the histology (grade 1–2 endometrioid carcinoma) was identified as an independent favourable prognostic factor. What the implications are of these findings for clinical practice and/or further research? This retrospective study identified that neither inflammatory parameters nor the nutritional index were revealed to be independent prognostic factors by multivariate analyses. Additional large-scale studies are required to confirm the prognostic significance of NLR, PLR and PNI in clinical stage IVB endometrial carcinoma to improve the poor prognosis of this disease.
Gynecologic oncology reports | 2018
Kaori Kiuchi; Kiyoshi Hasegawa; Shoko Ochiai; Nobuaki Kosaka; Hajime Kuroda; Yasushi Kaji; Ichio Fukasawa
Liposarcoma of the uterine corpus is extremely rare. We performed a laparotomy on a 55-year-old woman with the complaints of abdominal distension and genital bleeding who was found to have a uterine tumor, 17 × 16 cm in diameter. The preoperative diagnosis was a lipoma or lipoleiomyoma of the uterine corpus. However, pathological examination revealed proliferation of mature adipocytes and lipoblast-like atypical cells with small, weakly pleomorphic nuclei and foamy or vacuolated cytoplasm present within a fibrous septum. Immunohistochemistry showed that the tumor cells were focally positive for mouse double minute 2 homolog (MDM2). The final pathological diagnosis was a well-differentiated liposarcoma of International Federation of Gynecology and Obstetrics (FIGO) stage IB (pT1bNxM0). On magnetic resonance imaging (MRI), T1 -weighted and fat-saturated images showed high and low intensity in the tumor, respectively, suggesting that this tumor contained a fat component. The septum inside the tumor had a contrast enhancement on T1-weighted, gadolinium-enhanced imaging. The septum was nonuniformly thickened and partially nodular. In hindsight, these findings may have suggested a well-differentiated liposarcoma in the uterine corpus rather than a lipoma or lipoleiomyoma. Clinicians should be aware of the possibility of a liposarcoma of the uterine corpus when a neoplasm contains adipose tissue and a nonuniformly thickened or partially nodular septum on MRI.
日本産科婦人科學會雜誌 | 2016
Kayoko Takahashi; Kiyoshi Hasegawa; Takanori Sakamoto; Nobuaki Kosaka; Ichio Fukasawa
日本産科婦人科學會雜誌 | 2016
Kaori Kiuchi; Kiyoshi Hasegawa; Mariko Watanabe; Anriko Kanamori; Tatsuko Nagai; Nobuaki Kosaka; Ichio Fukasawa
International Cancer Conference Journal | 2016
Mariko Watanabe; Kiyoshi Hasegawa; Anriko Kanamori; Kaori Kiuchi; Tatsuya Kuno; Nobuaki Kosaka; Ichio Fukasawa
日本産科婦人科學會雜誌 | 2015
Kayoko Takahashi; Kazumi Tada; Nobuaki Kosaka; Kiyoshi Hasegawa; Takanori Sakamoto; Ichio Fukusawa