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Dive into the research topics where Seiji Kanayama is active.

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Featured researches published by Seiji Kanayama.


International Journal of Gynecological Cancer | 2008

A randomized study of screening for ovarian cancer: a multicenter study in Japan.

Hiroshi Kobayashi; Yoshihiko Yamada; Toshiyuki Sado; Mariko Sakata; Shozo Yoshida; Ryuji Kawaguchi; Seiji Kanayama; Hiroshi Shigetomi; Shoji Haruta; Yoriko Tsuji; Sachiyo Ueda; Takashi Kitanaka

Ovarian cancer is common in women from developed countries. We designed a prospective randomized controlled trial of ovarian cancer screening to establish an improved strategy for the early detection of cancers. Asymptomatic postmenopausal women were randomly assigned between 1985 and 1999 to either an intervention group (n= 41,688) or a control group (n= 40,799) in a ratio of 1:1, with follow-up of mean 9.2 years, in Shizuoka district, Japan. The original intention was to offer women in the intervention group annual screens by gynecological examination (sequential pelvic ultrasound [US] and serum CA125 test). Women with abnormal US findings and/or raised CA125 values were referred for surgical investigation by a gynecological oncologist. In December 2002, the code was broken and the Shizuoka Cohort Study of Ovarian Cancer Screening and Shizuoka Cancer Registry were searched to determine both malignant and nonmalignant diagnoses. Twenty-seven cancers were detected in the 41,688-screened women. Eight more cancers were diagnosed outside the screening program. Detection rates of ovarian cancer were 0.31 per 1000 at the prevalent screen and 0.38–0.74 per 1000 at subsequent screens; they increased with successive screening rounds. Among the 40,779 control women, 32 women developed ovarian cancer. The proportion of stage I ovarian cancer was higher in the screened group (63%) than in the control group (38%), which did not reach statistical significance (P= 0.2285). This is to our knowledge the first prospective randomized report of the ovarian cancer screening. The rise in the detection of early-stage ovarian cancer in asymptomatic postmenopausal women is not significant, but future decisions on screening policy should be informed by further follow-up from this trial.


Gynecological Endocrinology | 2009

The role of iron in the pathogenesis of endometriosis

Hiroshi Kobayashi; Yoshihiko Yamada; Seiji Kanayama; Naoto Furukawa; Taketoshi Noguchi; Shoji Haruta; Shozo Yoshida; Mariko Sakata; Toshiyuki Sado; Hidekazu Oi

Background. Endometriosis may cause symptoms including chronic pelvic pain and infertility, and increases susceptibility to the development of ovarian cancer. Genomic studies have started to delineate the wide array of mediators involved in the development of endometriosis. Understanding the mechanisms of endometriosis development and elucidating its pathogenesis and pathophysiology are intrinsic to prevention and the search for effective therapies. Method of study. The present article reviews the English language literature for biological, pathogenetic and pathophysiological studies on endometriosis. Several recent genomic studies are discussed in the context of endometriosis biology. Results. Severe hemolysis occurring during the development of endometriosis results in high levels of free heme and iron. These compounds oxidatively modify lipids and proteins, leading to cell and DNA damage, and subsequently fibrosis development. Recent studies based on genome-wide expression analysis technology have noted specific expression of heme/iron-dependent mediators in endometriosis. The heme/iron-dependent signaling pathway of endometriosis, which is providing new insights into the regulation of inflammation, detoxification and survival, is discussed. Conclusion. Several important endometriosis-specific genes overlap with those known to be regulated by iron. Other genes are involved in oxidative stress. Iron has a significant impact on endometriotic-cell gene expression. This review summarizes recent advances in the heme/iron-mediated signaling and its target genes, outlines the potential challenges to understanding of the pathogenesis and pathophysiology of endometriosis, and proposes a possible novel model.


Journal of Obstetrics and Gynaecology Research | 2008

Clinicopathologic features of ovarian cancer in patients with ovarian endometrioma

Ryuji Kawaguchi; Yoriko Tsuji; Shoji Haruta; Seiji Kanayama; Mariko Sakata; Yoshihiko Yamada; Hiroyuki Fujita; Hitomi Saito; Keiji Tsuneto; Hiroshi Kobayashi

Objective:  The purpose of this study was to describe the clinicopathologic features of malignant transformation in patients with ovarian endometrioma, their treatment and outcome in the Kinki region, Japan.


International Journal of Gynecological Cancer | 2012

Type II versus type III fertility-sparing abdominal radical trachelectomy for early-stage cervical cancer: a comparison of feasibility of surgical outcomes.

Miho Muraji; Tamotsu Sudo; Eriko Nakagawa; Sayaka Ueno; Senn Wakahashi; Seiji Kanayama; Takashi Yamada; Satoshi Yamaguchi; Kiyoshi Fujiwara; Ryuichiro Nishimura

Objective The purpose of this study was to compare surgical outcomes using modified (type II) and traditional (type III) abdominal radical trachelectomy (ART) for fertility-sparing surgery in early cervical cancer. Methods A prospectively maintained database of ART procedures was analyzed. Data were collected regarding age, stage, histology, operative outcome, surgical complication, and fertility outcome. Results We performed 23 fertility-sparing ARTs for patients with International Federation of Gynecology and Obstetrics stages IA to IB1 tumors of less than 2 cm between 2006 and 2010. Type III ART was attempted in 8 patients and modified ART in 15 patients. The median operating time was greater in the type III group compared with that in the type II group (305 vs 247 minutes; P < 0.02). The median surgical blood loss was greater in the type III ART group (580 mL; range, 250–988 mL) compared with that in the modified type II group (366 mL; range, 200–850 mL; P < 0.05). The median time to recovery of bladder dysfunction was less in the type II group (9 days; range, 3–10 days) than that in the type III group (13 days; range, 10–23 days; P < 0.01). There were no recurrences at the time of this report. Conclusions Type II ART provides surgical and pathological outcomes with better recovery of bladder function similar to those in type III ART. For patients with early cervical cancer who wish to preserve reproductive function, type II ART is a feasible and safe operation.


Journal of Gynecologic Oncology | 2013

CA-125 cut-off value as a predictor for complete interval debulking surgery after neoadjuvant chemotherapy in patients with advanced ovarian cancer

Naoto Furukawa; Yoshikazu Sasaki; Aiko Shigemitsu; Juria Akasaka; Seiji Kanayama; Ryuji Kawaguchi; Hiroshi Kobayashi

Objective In the present study, we evaluated changes in CA-125 cut-off values predictive of complete interval debulking surgery (IDS) after neoadjuvant chemotherapy (NAC) using receiver operating characteristic (ROC) analysis. Methods This retrospective single-institution study included patients with International Federation of Gynecology and Obstetrics (FIGO) stage III epithelial ovarian cancer and a pre-NAC serum CA-125 level of greater than 40 U/mL who were treated with neoadjuvant platinum-based chemotherapy followed by IDS between 1994 and 2009. Logistic regression analysis was used to evaluate univariate and independent multivariate associations with the effect of clinical, pathological, and CA-125 parameters on complete IDS, and ROC analysis was used to determine potential cut-off values of CA-125 for prediction of the possibility of complete IDS. Results Seventy-five patients were identified. Complete IDS was achieved in 46 (61.3%) patients and non-complete IDS was observed 29 (38.7%). Median pre-NAC CA-125 level was 639 U/mL (range, 57 to 6,539 U/mL) in the complete IDS group and 1,427 U/mL (range, 45 to 10,989 U/mL) in the non-complete IDS group. Median pre-IDS CA-125 level was 15 U/mL (range, 2 to 60 U/mL) in the complete IDS group and 53 U/mL (range, 5 to 980 U/mL) in the non-complete IDS group (p<0.001). Multivariate analyses performed with complete IDS as the endpoint revealed only pre-IDS CA-125 as an independent predictor. The odds ratio of non-complete IDS was 10.861 when the pre-IDS CA-125 level was greater than 20 U/mL. Conclusion The present data suggest that in the setting of IDS after platinum-based NAC for advanced ovarian cancer, a pre-IDS CA-125 level less than 20 U/mL is an independent predictor of complete IDS.


International Journal of Gynecology & Obstetrics | 2007

Serum CA125 level before the development of ovarian cancer

Hiroshi Kobayashi; Hidekazu Ooi; Yoshihiko Yamada; Mariko Sakata; Ryuji Kawaguchi; Seiji Kanayama; Kazuhiro Sumimoto; Toshihiko Terao

Little is known about the natural history of ovarian cancer with respect to the change of serum CA125 level.


Journal of Obstetrics and Gynaecology Research | 2008

Giant abdominal tumor of the ovary

Sachiyo Ueda; Yoshihiko Yamada; Yoriko Tsuji; Ryuji Kawaguchi; Shoji Haruta; Hiroshi Shigetomi; Seiji Kanayama; Shozo Yoshida; Mariko Sakata; Toshiyuki Sado; Koji Kitanaka; Hiroshi Kobayashi

A giant abdominal tumor can exert a mass effect on surrounding structures. We report here a 34‐year‐old single female who presented with an increased abdominal girth and was subsequently found to have a giant abdominal mass. Large volume aspiration (85 L) at a slow rate (1 L/min) was initially performed before surgical resection to prevent the development of severe clinical hypotension after large volume aspiration. The patient underwent left salpingo‐oophorectomy. Histology revealed a serous cystadenoma of the ovary. Systemic hemodynamics were sequentially measured during the perioperative period. The patient is now well.


Oncology Reports | 2011

Signaling pathway involved in cyclooxygenase-2 up-regulation by hepatocyte growth factor in endometrial cancer cells

Yoriko Yoshizawa; Yoshihiko Yamada; Seiji Kanayama; Hiroshi Shigetomi; Ryuji Kawaguchi; Shozo Yoshida; Akira Nagai; Naoto Furukawa; Hidekazu Oi; Hiroshi Kobayashi

Hepatocyte growth factor (HGF) is up-regulated in tissue repair and has been implicated in playing a role in this process through its anti-apoptotic and proliferative activities. Cyclooxygenase-2 (COX-2) is an inducible enzyme in the biosynthetic pathway of prostaglandins, and its activation has been shown to play an important role in cell growth. We previously reported that HGF significantly inhibited anoikis, possibly through the up-regulation of COX-2 expression in the endometrial RL95-2 cancer cell line. Here, we report that i) treatment of RL95-2 cells with HGF resulted in phosphorylation of the HGF receptor c-Met, activation of Akt and IκB, translocation of NF-κB into the nucleus, and up-regulation of COX-2 mRNA; ii) the IκB-α phosphorylation inhibitor BAY11-7082 and the selective COX-2 inhibitor CAY10452 blocked HGF-mediated anoikis resistance in RL95-2 cells; and iii) HGF induced migration and invasion in RL95-2 cells, while the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 and CAY10452 blocked these effects of HGF stimulation. Our data suggest that HGF possesses chemotactic ability, has anti-apoptosis action, and induces cellular infiltration via the PI3K/Akt pathway; it also triggers NF-κB activation and up-regulates COX-2 gene expression in endometrial cancer cells.


Archives of Gynecology and Obstetrics | 2008

Massive ovarian edema in pregnancy after ovulation induction using clomiphene citrate

Ryuji Kawaguchi; Sachiyo Ueda; Yoriko Tsuji; Shoji Haruta; Seiji Kanayama; Yoshihiko Yamada; Hidekazu Ooi; Hiroshi Kobayashi

BackgroundMassive ovarian edema is a benign enlargement of the ovary caused by accumulation of fluid occurring mainly in young women. Most cases are thought to result from venous and lymphatic obstruction.Case reportWe treated a 40-year-old multiparous pregnant woman with massive ovarian edema who had been received clomiphene citrate. She was admitted at 13th week of pregnancy for acute pelvic pain. Left oophorectomy was performed, and pathologic examination disclosed massive ovarian edema. Our report is the first case of massive ovarian edema with pregnancy after ovulation induction using clomiphene citrate.


Mediators of Inflammation | 2012

Chemokine and Free Fatty Acid Levels in Insulin-Resistant State of Successful Pregnancy: A Preliminary Observation

Katsuhiko Naruse; Taketoshi Noguchi; Toshiyuki Sado; Taihei Tsunemi; Hiroshi Shigetomi; Seiji Kanayama; Juria Akasaka; Natsuki Koike; Hidekazu Oi; Hiroshi Kobayashi

Increased insulin resistance and inflammatory action are observed in pregnancy-induced hypertension (PIH), but similar insulin resistance is observed also in successful pregnancy. To estimate insulin resistance and inflammatory activity in normal pregnancy and PIH, serum concentrations of free fatty acids (FFA; corrected with albumin to estimate unbound FFA), monocyte chemoattractant protein (MCP)-1, and high-molecular weight (HMW) adiponectin were measured in severe PIH patients with a BMI less than 25 kg/m2 and were measured 3 times during the course of pregnancy in women with normal pregnancies. FFA/albumin, MCP-1, and HMW adiponectin concentrations were significantly higher in PIH patients than in women with normal pregnancies. The 3 measurements of FFA/albumin showed a significant increase through the course of uncomplicated pregnancies. In contrast, MCP-1 and HMW adiponectin were significantly decreased during the course of pregnancy. These results suggest that the reduced MCP-1 concentration in normal pregnancy may be a pathway to inhibit the induction of pathological features from physiological insulin resistance and homeostatic inflammation.

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Shoji Haruta

Nara Medical University

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Yoriko Tsuji

Nara Medical University

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Hidekazu Oi

Nara Medical University

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