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Dive into the research topics where Sanshiro Okamoto is active.

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Featured researches published by Sanshiro Okamoto.


Journal of Lower Genital Tract Disease | 2015

Clinicopathologic features and treatment outcomes of primary extramammary Paget disease of the vulva.

Hidetaka Nomura; Maki Matoda; Sanshiro Okamoto; Eiji Kondo; Kohei Omatsu; Kazuyoshi Kato; Nobuhiro Takeshima

Objective The aim of this study was to identify the clinicopathologic features and treatment outcome of primary extramammary Paget disease of the vulva (EMPDV). Materials and Methods We performed a retrospective analysis of 14 patients who were treated at our center from April 1994 to November 2010. Results The mean age of patients in our sample was 64.4 years (range = 47–83 y). We observed intraepithelial and invasive EMPDV in 11 (78.6%) and 3 (21.4%) patients, respectively. Moreover, we observed a positive incision margin in 9 patients (64.3%). During a median follow-up period of 69.5 months (range = 32–221 mo), we observed recurrence in 3 patients (21.4%), 2 of whom had invasive EMPDV and 1 had intraepithelial EMPDV. Time to recurrence was 16 and 18 months for patients with invasive EMPDV and 98 months for patients with intraepithelial EMPDV. The recurrence rate of intraepithelial EMPDV and invasive EMPDV was significantly different (9.1% and 66.7%, respectively, p < .028). Local recurrence occurred in all 3 patients, necessitating further surgical resection. One patient with recurrence of invasive EMPDV received adjuvant radiotherapy but died 101 months after the initial treatment. The other 2 patients remained alive without recurrence. We did not observe distant recurrence. Conclusions The recurrence rate of invasive EMPDV was high. However, because distant metastasis is rare, repeat surgical excision for recurrent EMPDV and long-term observation are necessary for a good prognosis.


International Journal of Gynecological Cancer | 2014

Recurrence patterns of advanced ovarian, fallopian tube, and peritoneal cancers after complete cytoreduction during interval debulking surgery.

Tomoka Usami; Kazuyoshi Kato; Tomoko Taniguchi; Akiko Abe; Hidetaka Nomura; Akiko Yamamoto; Maki Matoda; Sanshiro Okamoto; Eiji Kondo; Kohei Omatsu; Yasutaka Kawamata; Nobuhiro Takeshima

Objectives Similar to primary debulking surgery, complete resection of all macroscopic diseases during interval debulking surgery (IDS) is the primary objective while using neoadjuvant chemotherapy followed by IDS for advanced ovarian, fallopian tube, and peritoneal cancers. However, most patients develop recurrent disease even after complete cytoreduction during IDS. This study aims to identify recurrence patterns of the ovarian, fallopian tube, and peritoneal cancers in patients who underwent complete cytoreduction during IDS. Methods We retrospectively reviewed data of patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers who were treated at our hospital from January 1, 2005, to December 31, 2011. Results In this study, 105 patients underwent neoadjuvant chemotherapy followed by IDS and achieved complete cytoreduction. The median follow-up period was 42.1 months. Recurrence was documented in 70 patients (66.7%), and 35 (33.3%) showed no evidence of disease. Peritoneal dissemination was the most common recurrence (60.0%) observed. In multivariate analysis, positive peritoneal cytology (P = 0.0003) and elevated pre-IDS serum CA125 levels (P = 0.046) were independent risk factors for recurrence. Conclusions After complete cytoreduction during IDS in patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers, positive peritoneal cytology at IDS and elevated pre-IDS CA125 levels are associated with an increased risk of cancer recurrence. Positive peritoneal cytology during IDS is a particularly strong predictive factor for poor outcomes in these patients.


International Journal of Gynecological Cancer | 2013

Platinum-free interval in second-line chemotherapy for recurrent cervical cancer.

Maki Matoda; Terumi Tanigawa; Kohei Omatsu; Norichika Ushioda; Akiko Yamamoto; Sanshiro Okamoto; Yasutaka Kawamata; Kazuyoshi Kato; Kenji Umayahara; Nobuhiro Takeshima

Objective The purpose of this study was to determine whether the platinum-free interval (PFI) was a predictive indicator in second-line treatment of cervical cancer in patients who had undergone prior platinum-based chemotherapy. The role of the PFI in selecting the second-line regimen in other gynecologic malignancies is also discussed. Methods In this retrospective study, we examined the clinical records of patients with recurrent or metastatic cervical cancer who had received platinum-containing combination regimens as second-line chemotherapy. All patients had received prior platinum-containing chemotherapy or concurrent chemoradiotherapy. Results The overall response rate to second-line chemotherapy was 25.8%; 7 patients achieved a complete response and 17 a partial response. The median progression-free survival (PFS) was 5.1 months and median overall survival (OS) was 13.5 months. The response rate was 12.5%, 14.2%, 20.0%, 22.2%, and 55.0%; median PFS was 4.0, 5.1, 4.4, 5.8, and 7.4 months; and median OS was 10.2, 14.4, 11.9, 16.3, and 19.7 months when PFI was within 3, 3 to 5, 6 to 11, 12 to 23, and more than 24 months, respectively. Age (>50 years), size (>3 cm), prior radiotherapy, and PFI (>24 months) were identified as prognostic factors in the multivariate analysis for PFS and OS. Conclusions The results indicate that a PFI of more than 24 months is the discriminating point between platinum-sensitive and platinum-resistance cervical cancer. This indicates that PFI offers a useful tool in selecting agents for second-line chemotherapy in a wide range of gynecologic malignancies.


International Journal of Gynecological Cancer | 2015

Prognosis for endometrial cancer patients treated with systematic pelvic and para-aortic lymphadenectomy followed by platinum-based chemotherapy.

Kotaro Sueoka; Kenji Umayahara; Akiko Abe; Tomoka Usami; Akiko Yamamoto; Hidetaka Nomura; Maki Matoda; Sanshiro Okamoto; Kohei Omatsu; Eiji Kondo; Kazuyoshi Kato; Nobuhiro Takeshima

Objective The purpose of this study was to analyze the prognosis for endometrial cancer patients treated with systematic pelvic and para-aortic lymphadenectomy (PLA and PALA) followed by platinum-based chemotherapy. Materials and Methods From 1994 to 2004, in the Cancer Institute Hospital, 502 patients who were surgically treated with systematic PLA and PALA were enrolled in this study. Their prognosis and clinicopathological features were retrospectively reviewed. Results One hundred ninety-one (38.0%) patients received adjuvant platinum-based chemotherapy. Lymph node (LN) metastasis was observed in 80 (15.9%) patients, pelvic-only LN metastasis in 27 (5.4%), para-aortic-only LN metastasis in 15 (3.0%), and both pelvic and para-aortic LN metastasis in 38 (7.6%). The median number of metastatic LNs was 2 (range, 1–57), 1 (range, 1–4), and 6 (range, 2–50) in patients with pelvic-only, para-aortic-only, and both pelvic and para-aortic LN metastasis, respectively (P < 0.001). Only 2.6% (2/76) of patients with no myometrial invasion had LN metastasis, and no less than 8.9% (22/247) of patients with myometrial invasion (limited to the inner half) had LN metastasis. Five-year overall survival (OS) for LN metastasis–negative and –positive patients was 96.7% and 76% (P < 0.001), respectively. Five-year OS for patients with metastasis in 1 or 2 LNs was 84.8% and was significantly higher than that for patients with metastasis in 3 or more LNs (57.8%; P = 0.011). In patients with LN metastasis, 5-year OS of endometrioid adenocarcinoma and non–endometrioid adenocarcinoma cell types was 90.2% and 56.7% (P = 0.0016), respectively. Conclusions Under the settings of thorough PLA and PALA followed by intensive platinum-based chemotherapy for endometrial cancer, metastasis in 1 or 2 LNs seems to have little effect on survival, although para-aortic LNs are involved. This therapeutic strategy could not improve the prognosis of patients with metastasis in 3 or more LNs or patients with non–endometrioid adenocarcinoma cell types along with LN involvement.


International Journal of Gynecological Cancer | 2015

Clinical characteristics of non-squamous cell carcinoma of the vagina.

Hidetaka Nomura; Maki Matoda; Sanshiro Okamoto; Kohei Omatsu; Eiji Kondo; Kazuyoshi Kato; Kenji Umayahara; Nobuhiro Takeshima

Objective The prognosis and vaginal disease control rate after treatment with radiotherapy or concurrent chemoradiotherapy (CCRT) are reported to be worse for primary non–squamous cell carcinoma (non-SCC) of the vagina than for squamous cell carcinoma (SCC) of the vagina. Our objective was to examine the clinicopathological characteristics of primary non-SCC of the vagina and suggest an appropriate treatment strategy. Materials and Methods In a retrospective chart review, we identified patients with primary vaginal cancer who were treated in our hospital between 1990 and 2013. Twelve patients with histologically diagnosed non-SCC were identified. None of these cases was associated with in utero diethylstilbestrol exposure. Clinical data, including patient characteristics, stage, treatment outcome, and the site of recurrence, were recorded. Results The 12 identified cases included 5 of clear cell carcinoma, 3 of adenocarcinoma, 2 of adenosquamous carcinoma, 1 of carcinosarcoma, and 1 of mucinous adenocarcinoma. The most common location of the tumor was the upper one third of the vagina (56%). Initial treatment involved surgery in 8 patients. Among them, 4 received adjuvant chemotherapy, 3 received adjuvant radiotherapy, and 1 received neither. The initial treatment among the remaining 4 patients was CCRT in 1, neoadjuvant chemotherapy in 2 (followed by CCRT or surgery), and best supportive care in 1. The last 3 patients had lung metastasis. Six patients experienced recurrence, including vaginal recurrence in 2 patients and lymphatic spread in 4 patients. Five of these 6 patients experienced hematogenous metastasis. Conclusions Despite the absence of in utero diethylstilbestrol exposure in our cases, clear cell adenocarcinoma accounted for 41.7% (5/12) cases. A favorable local control rate was achieved in all 12 cases, but the incidence of distant metastasis, especially to the lung, was high. Prevention of distant metastasis may be the key to treating patients with non-SCC of the vagina.


Journal of Cancer Science & Therapy | 2018

Analysis of A Single Para-Aortic Lymph Node Metastasis in Endometrial Cancer

Motoki Matsuura; Akimasa Takahashi; Hidetaka Nomura; Maki Matoda; Sanshiro Okamoto; Hiroyuki Kanao; Kohei Omatsu; Kazuyoshi Kato; Kuniko Utsugi; Nobuhiro Takeshima

Objective: To determine the indication for lymph node dissection in patients with endometrial cancer, we investigated the incidence and distribution of single metastatic lymph nodes in patients who underwent systematic pelvic and para-aortic lymph node dissection.Methods: This study involved 910 patients with endometrial cancer who were treated at the Cancer Institute Hospital, Japan, between January 1994 and December 2015. All patients underwent an open hysterectomy with bilateral salpingo-oophorectomy and pelvic and para-aortic lymph nodes dissection.Results: Lymph node metastasis was observed in 199 patients (21.9%), 45 (5%) of whom had single lymph node metastasis. Single lymph node metastasis accounted for 22.6% of all metastatic cases. Myometrial invasion >50% was observed in 30 patients, whereas 15 patients had <50% myometrial invasion. When mapping single lymph node metastatic sites, the para-aortic area had a frequency of 31.1% (14 cases). The distribution of single metastatic lymph nodes spanned a wide area between the pelvic and para-aortic regions. Considering single metastatic nodes and myometrial invasion, 8 patients (53.3%) who had myometrial invasion <50% had a single metastatic node in the para-aortic region. Four of 9 patients (45%) considered low-risk (endometrioid Grade 1-2, invasion depth <50%, no lymphovascular space invasion) showed metastasis to the para-aortic areas.Conclusion: Single metastatic lymph nodes were widely distributed between the pelvic and para-aortic regions, suggesting that detection of a sentinel lymph node in patients with endometrial cancer could be problematic.


International Journal of Gynecological Cancer | 2016

Review of Treatment and Prognosis of Stage IVB Cervical Carcinoma.

Tomoka Usami; Akimasa Takahashi; Maki Matoda; Sanshiro Okamoto; Eiji Kondo; Hiroyuki Kanao; Kenji Umayahara; Nobuhiro Takeshima

Objectives In most patients, stage IVB cervical cancer is incurable, and the outcomes are poor. There is significant individual variation in patients with stage IVB cervical cancer, in whom standard treatment has not been well defined. This study aims to review the outcomes and discuss treatment strategies in patients with stage IVB cervical cancer. Methods From January 1, 1992, to December 31, 2011, we retrospectively reviewed the data of patients with stage IVB cervical cancer who were given a diagnosis at the Department of Gynecology of the Cancer Institute Hospital. Results A total of 111 patients were enrolled. At the time of analysis, the median overall survival (OS) was 16.6 months (range, 0.2–120.9 months), and the 5-year OS rate was 20.2%. The 5-year OS rate was 59.4% for those with only para-aortic lymph node metastases; 24.8% for those with lymphogenous metastases, excluding those with only para-aortic lymph node metastases; 6.1% for those with hematogenous metastases; and 0% for those with disseminated metastases. The OS in patients with lymphogenous metastases was better compared with that of those with either hematogenous or disseminated metastases (P < 0.0001). In multivariate analysis, the performance status, site of metastases (only lymph node or other metastases), and local stage were all independent prognostic factors. Conclusions We determined performance status, site of metastases (only lymph node or other metastases), and local stage as independent prognostic factors in patients with stage IVB cervical cancer. Regarding treatment, we confirmed that the effectiveness of chemotherapy was also of significance.


Journal of Minimally Invasive Gynecology | 2018

Laparoscopic Anterior Pelvic Exenteration with Super Radical Parametrectomy for a Recurrent Low-Grade Endometrial Sarcoma That is Resistant to Hormone Therapy and Chemotherapy

Hiroyuki Kanao; Tsuyoshi Hisa; Makiko Omi; Minoru Nagashima; Shuhei Okamoto; Yoichi Aoki; Terumi Tanigawa; Maki Matoda; Sanshiro Okamoto; Hidetaka Nomura; Kohei Omatsu; Kazuyoshi Kato; Kuniko Utsugi; Nobuhiro Takeshima

STUDY OBJECTIVE To show total laparoscopic complete resection of a recurrent low-grade endometrial sarcoma. DESIGN Step-by-step demonstration of the technique of laparoscopic anterior pelvic exenteration with super radical parametrectomy, including the explanation of detailed pelvic anatomy (Canadian Task Force classification III). SETTING Low-grade endometrial stromal sarcoma (LGESS) is a rare malignancy that makes up around 0.2% of all uterine malignancies [1]. Total abdominal hysterectomy and bilateral salpingo-oophorectomy is a standard treatment; however, the recurrence risk is quite high [2]. For a recurrent LGESS that is resistant to hormone therapy and chemotherapy, complete resection with negative surgical margins (R0 resection) can be the most promising method [3]. PATIENT The patient had undergone total abdominal hysterectomy and bilateral salpingo-oophorectomy because of a LGESS. Almost 20 years later, a recurrent LGESS was detected at the vaginal stump, and the patient underwent several rounds of chemotherapy and hormonal therapy. These treatments were inefficacious, and the recurrent tumor progressed. An abdominal computed tomographic scan revealed that the recurrent tumor occupied the vaginal stump, involved the bladder and the left ureter, and extended to the left pelvic sidewall. INTERVENTIONS Anterior pelvic exenteration with super radical parametrectomy was performed laparoscopically with no blood transfusion. R0 resection could be achieved without any intraoperative and postoperative complications. Without any adjuvant treatment, there has been no sign of recurrence during the 12 months that have passed since the surgery. This video obtained institutional review board approval through our local ethics committee in the Cancer Institutional Hospital (institutional review board number 2016-1007). CONCLUSION The good visualization and meticulous dissection provided during laparoscopic surgery can make the approach advantageous and may contribute to R0 achievement.


Journal of Minimally Invasive Gynecology | 2018

En Bloc Resection of an Aggressive Angiomyxoma by a Novel Combination Laparoscopic and Open Perineal Approach

Hiroyuki Kanao; Yoichi Aoki; Terumi Tanigawa; Maki Matoda; Sanshiro Okamoto; Hidetaka Nomura; Kohei Omatsu; Kazuyoshi Kato; Kuniko Utsugi; Nobuhiro Takeshima

STUDY OBJECTIVE To show a novel combination laparoscopic and open perineal approach to complete resection of aggressive angiomyxoma. DESIGN Step-by-step video demonstration of the combination approach (Canadian Task Force classification III). SETTING Combined laparoscopic and open perineal approach was performed in the tertiary center. PATIENT A 46-year-old woman presented with an 8-cm vulvar mass, diagnosed as an aggressive angiomyxoma. The patient, who strongly desired to preserve her uterus and ovaries, provided informed consent for resection of the tumor by our combination approach, also approved by our Institutional Review Board. INTERVENTION Combined laparoscopic and open perineal approach. MEASUREMENTS AND MAIN RESULTS Aggressive angiomyxoma is a rare mesenchymal neoplasm that occurs most often in the female pelviperineal region [1]. Aggressive angiomyxoma is locally infiltrative, and high postoperative local recurrence rates (36%-72%) due to incomplete resection have been reported [2]. Therefore, until recently, wide surgical excision with tumor-free margins have been the most commonly accepted treatment. However, aggressive angiomyxoma is a benign, slow-growing tumor, and because extensive surgical resection, which is associated with high operative morbidity rates, has not been shown to have a significant effect on prognosis, a more conservative procedure may be preferable [3]. The mass was located mainly at the left ischiorectal fossa, but it extended above the pelvic diaphragm and was attached to internal obturator muscle, vagina, bladder, urethra, and rectum. We excised the tumor completely and without complications by a combined laparoscopic and open perineal approach. Twelve months have passed since the surgery, and there has been no adjuvant treatment and no sign of recurrence. CONCLUSION Our combination approach to aggressive angiomyxoma in the pelviperineal region is technically feasible, and the good visualization and meticulous dissection provided during the laparoscopic portion of the surgery contribute to complete resection.


Japanese Journal of Clinical Oncology | 2018

Maintenance hormonal therapy after treatment with medroxyprogesterone acetate for patients with atypical polypoid adenomyoma

Hidetaka Nomura; Yuko Sugiyama; Terumi Tanigawa; Maki Matoda; Sanshiro Okamoto; Kohei Omatsu; Hiroyuki Kanao; Kazuyoshi Kato; Kuniko Utsugi; Nobuhiro Takeshima

Background As atypical polypoid adenomyoma (APA) has been reported to be a hormone-related tumor, we aimed to analyze the efficacy and safety of maintenance hormonal therapy after fertility-preserving treatment of these patients with medroxyprogesterone acetate (MPA). Methods Data were retrospectively analyzed from patients with APA who were treated with a fertility-preserving regimen including MPA between October 2001 and December 2011. Eighteen patients were treated with MPA and 14 (77.8%) achieved either a complete or a partial response after the planned treatment. Five patients took progestin for maintenance therapy. Results Eighteen patients were treated for a mean observation period of 96.7 months. While taking the maintenance therapy, no patient had APA relapse. One patient developed well-differentiated endometrioid adenocarcinoma 18 months after she stopped taking maintenance progestin. Eleven patients without maintenance therapy underwent hysterectomy, andnine of them developed well-differentiated endometrial cancer. Through univariate analysis, there was a significant difference in time to hysterectomy between patients with and without maintenance therapy (P = 0.015). Through multivariate analysis, body mass index (BMI), menstrual status before protocol therapy, maintenance treatment, and pregnancy were found to be significantly associated with a lower risk of hysterectomy. No patient had a recurrence of APA after hysterectomy during the observation period (median, 54 months; range, 2-148 months). Conclusion No patient showed progression while receiving hormonal therapy, including initial protocol therapy. Maintenance hormonal therapy after treatment with MPA was highly effective and safe, particularly in patients with BMI ≧24 kg/m2 and irregular menstruation cycle.

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Maki Matoda

Japanese Foundation for Cancer Research

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Kohei Omatsu

Japanese Foundation for Cancer Research

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Nobuhiro Takeshima

Japanese Foundation for Cancer Research

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Hidetaka Nomura

Japanese Foundation for Cancer Research

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Kuniko Utsugi

Japanese Foundation for Cancer Research

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Hiroyuki Kanao

Japanese Foundation for Cancer Research

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Terumi Tanigawa

Japanese Foundation for Cancer Research

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