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Featured researches published by Shoichiro Iwatsuki.


Urology | 2010

Laparoscopic Management for Fibroepithelial Polyp Causing Ureteropelvic Junction Obstruction in a Child

Shoichiro Iwatsuki; Yoshiyuki Kojima; Kentaro Mizuno; Keiichi Tozawa; Kenjiro Kohri; Yutaro Hayashi

An 11-year-old boy with episodes of intermittent gross hematuria and recurrent left flank pain was referred to our institute with left ureteropelvic junction (UPJ) obstruction. (99m)Tc diethylenetriamine pentaacetic acid (DTPA) renography revealed an obstructive pattern in the left kidney, and the existence of a crossing vessel at the UPJ was suspected with excretory urography. Laparoscopic surgery was performed, and intraoperatively no aberrant vessels were found. Upon opening the ureter, a solitary round polyp was found. The segment of the UPJ area containing the polyp was completely removed, followed by laparoscopic dismembered pyeloplasty. Pathologic findings demonstrated a benign fibroepithelial polyp.


The Journal of Urology | 2011

Endocrine Assessment of Prepubertal Boys With a History of Cryptorchidism and/or Hypospadias: A Pilot Study

Shoichiro Iwatsuki; Yoshiyuki Kojima; Kentaro Mizuno; Hideyuki Kamisawa; Yukihiro Umemoto; Shoichi Sasaki; Kenjiro Kohri; Yutaro Hayashi

PURPOSE Four disorders, including poor semen quality, testicular cancer, cryptorchidism and hypospadias, are thought to represent testicular dysgenesis syndrome and have been hypothesized to share a common etiology. We predicted testicular function in prepubertal boys with a history of cryptorchidism and/or hypospadias by measuring serum hormone levels. MATERIALS AND METHODS A total of 82 prepubertal boys who underwent orchiopexy and/or hypospadias repair in childhood were enrolled in the study. Patients were surgically treated for cryptorchidism (23 in group 1), hypospadias (49 in group 2), cryptorchidism and hypospadias (10 in group 3), and hydrocele testis (7 in control group 4). Serum hormones, including luteinizing hormone, follicle-stimulating hormone and total testosterone, were measured separately by age less than 12.5, 12.5 to 13.5 and greater than 13.5 years, and by Tanner pubertal stage. RESULTS Follicle-stimulating hormone in group 3 was significantly higher than in groups 1, 2 and 4 at ages 12.5 to 13.5 and greater than 13.5 years, and for Tanner stages 2 and 3 (p <0.05). However, luteinizing hormone and testosterone did not differ among the groups regardless of age or Tanner stage. Group 3 patients had significantly higher follicle-stimulating hormone regardless of the severity of cryptorchidism or hypospadias. CONCLUSIONS Data suggest that testicular function in patients with cryptorchidism plus hypospadias is more severely impaired than that in patients with cryptorchidism or hypospadias, lending clinical support to the testicular dysgenesis syndrome hypothesis of a common origin.


Asian Pacific Journal of Cancer Prevention | 2015

Laparoscopic Versus Open Radical Cystectomy for Patients Older than 75 Years: a Single-Center Comparative Analysis

Takahiro Yasui; Keiichi Tozawa; Ryosuke Ando; Takashi Hamakawa; Shoichiro Iwatsuki; Kazumi Taguchi; Daichi Kobayashi; Taku Naiki; Kentaro Mizuno; Atsushi Okada; Yukihiro Umemoto; Noriyasu Kawai; Shoichi Sasaki; Yutaro Hayashi; Kenjiro Kohri

BACKGROUND To explore the safety, efficacy, and oncological outcome of 3-port laparoscopic radical cystectomy (LRC) compared to open radical cystectomy (ORC) in patients older than 75 years. MATERIALS AND METHODS From June 2010 to July 2014, we analyzed 16 radical cystectomies in patients older than 75 years (LRC group=8; ORC group=8). Demographic parameters, operative variables, and perioperative outcome in the 2 groups were retrospectively collected, analyzed, and compared. RESULTS Patients in both groups had comparable preoperative characteristics. A significantly longer operating time (476 vs. 303 min, P=0.0002) and less estimated blood loss (627 vs. 2,106 mL, P=0.021) were observed in the LRC group compared to the ORC group. Infection and ileus were the most common early complications after surgery. Patients who underwent ORC suffered from more postoperative infection (22.2% vs. 0.0%, P=0.054) and ileus (25.0% vs. 12.5%, P=0.521) than the LRC group, but the difference was not significant. CONCLUSIONS Judging from this initial trial, 3-port LRC can be safely carried out in elderly patients. We suggest 3-port LRC as the primary intervention to treat muscle-invasive or high-risk nonmuscle-invasive bladder cancer in elderly patients with an otherwise relatively long life expectancy.


Urology | 2010

Single-nucleotide polymorphism in WT1 gene in a hyperplastic intralobar nephrogenic rest with botryoid protrusion.

Kentaro Mizuno; Yutaro Hayashi; Keiichi Tozawa; Shoichiro Iwatsuki; Yoshiyuki Kojima; Kenjiro Kohri

Nephrogenic rests are nodular collections of undifferentiated renal blastema cells in the postnatal kidney that are recognized as putative precursor lesions of Wilms tumor. In this study, we report the case of a 3-year-old boy who was diagnosed with a hyperplastic intralobar nephrogenic rest extending through the renal pelvis and ureter. After radical nephrectomy, adjuvant chemotherapy was performed as done in stage II Wilms tumor. We also investigated the mutation of the WT1 gene and identified a related single-nucleotide polymorphism (rs16754). We consider that not only various genetic mutations but also single-nucleotide polymorphisms or other epigenetic factors might be involved in the development of Wilms tumor.


Journal of Andrology | 2017

Chromosomal anomalies and sperm retrieval outcomes of patients with non‐obstructive azoospermia: a case series

T. Takeda; Shoichiro Iwatsuki; Takashi Hamakawa; Kentaro Mizuno; Hiroyuki Kamiya; Yukihiro Umemoto; Hiroki Kubota; Yasue Kubota; Shoichi Sasaki; Takahiro Yasui

Some preoperative factors affecting the outcome of microdissection testicular sperm extraction (micro‐TESE) have been previously evaluated. However, other than Klinefelter syndrome (KS), no other chromosomal anomalies have been discussed in the context of sperm retrieval outcomes. The objective of this study was to describe chromosomal anomalies and their relationship with sperm retrieval outcomes in patients with non‐obstructive azoospermia (NOA). Of the 197 NOA patients whose clinical records were retrospectively reviewed, 144 (73.1%) had normal 46,XY karyotype, 40 (20.3%) had KS (47,XXY), and 13 (6.6%) had other chromosomal anomalies (autosomal in seven cases and sex‐chromosomal anomalies in six). Of the seven patients with autosomal anomalies, two had the reportedly normal variant 46,XY,inv(9)(p12;q13). Testicular volume and serum hormone levels (luteinizing hormone, follicle‐stimulating hormone, and total testosterone) of the patients with chromosomal anomalies other than KS were comparable to those of the patients with normal karyotype. The sperm retrieval rate of the patients with 46,XY karyotype, KS, or other chromosomal anomalies were 27.1%, 22.5%, and 15.4%, respectively, with no statistically significant difference. However, among the samples collected from the 13 patients with chromosomal anomalies other than KS, only those from the two patients with the normal variant 46,XY,inv(9)(p12;q13) contained spermatozoa. Among our series of NOA patients, the incidence of autosomal anomalies was higher than that generally noted among neonates, which suggests that not only sex‐chromosomal anomalies but also autosomal anomalies may affect the development of NOA. Furthermore, our findings suggest that sperm retrieval outcome is more unfavorable in NOA patients with chromosomal anomalies than in NOA patients with 46,XY karyotype or KS, despite the use of micro‐TESE.


Journal of Andrology | 2017

Effect of obesity on sperm retrieval outcome and reproductive hormone levels in Japanese azoospermic men with and without Klinefelter syndrome

Shoichiro Iwatsuki; Shoichi Sasaki; Kazumi Taguchi; Takashi Hamakawa; Kentaro Mizuno; Atsushi Okada; Yasue Kubota; Yukihiro Umemoto; Yutaro Hayashi; Takahiro Yasui

Obesity is reported to have adverse effects on semen quality and the endocrine system. In this study, we evaluated the effect of obesity on sperm retrieval outcome and reproductive hormone levels in Japanese men with non‐obstructive azoospermia (NOA). This study is based on the clinical records of 217 men [172 with a 46,XY karyotype, 45 with Klinefelter syndrome (KS)] with NOA who underwent microdissection testicular sperm extraction at Nagoya City University Hospital between January 2004 and December 2014. Body mass index (BMI) and serum levels of luteinizing hormone (LH), follicle‐stimulating hormone (FSH), and total testosterone (TT) were measured in all patients. In a subset of patients, bioavailable testosterone (cBAT) also was calculated. Values were evaluated separately in patients with and without KS. Sperm retrieval rates (SRRs) in 46,XY men with a BMI <25 kg/m2 and ≥25 kg/m2 were 29.3% and 18.4%, respectively (p = 0.142), while SRRs in KS men with a BMI <25 kg/m2 and ≥25 kg/m2 were 25.0% and 35.3%, respectively (p = 0.460). TT level in men with a BMI ≥25 kg/m2 was lower than that in men with a BMI <25 kg/m2, regardless of KS status. According to Pearson product‐moment correlation coefficients, TT and cBAT levels tended to have negative correlations with BMI; however, statistical significance was observed only for TT level in 46,XY men (r = 0.340, p < 0.001). LH and FSH levels were negatively correlated with BMI in KS men (r = −0.466, p = 0.001 and r = −0.647, p < 0.001, respectively), but not in 46,XY men. These results suggest that obesity may be irrelevant to sperm retrieval outcome in patients with NOA. The negative correlations between gonadotropins and BMI in patients with KS suggest an underlying suppressive effect on gonadotropin excretion, which is distinctive in obese patients with KS.


Journal of Medical Case Reports | 2016

Nonpalpable testicular pure seminoma with elevated serum alpha-fetoprotein presenting with retroperitoneal metastasis: a case report

Shoichiro Iwatsuki; Taku Naiki; Noriyasu Kawai; Toshiki Etani; Keitaro Iida; Ryosuke Ando; Takashi Nagai; Atsushi Okada; Keiichi Tozawa; Yosuke Sugiyama; Takahiro Yasui

BackgroundPatients with a primary pure seminoma in the testis who have elevated serum alpha-fetoprotein are rare and should be treated as patients with nonseminomatous germ cell tumors. However, nonpalpable testicular tumors in this condition have never been reported. We describe a case of nonpalpable pure testicular seminoma with elevated serum alpha-fetoprotein presenting retroperitoneal metastasis.Case presentationA 29-year-old Asian man was referred to our hospital with right flank pain. Computed tomography showed a mass located between his aorta and inferior vena cava, but a testicular tumor was not detected. His serum levels of lactate dehydrogenase, alpha-fetoprotein, and DUPAN-2 were high. Although no tumor or nodule was palpable in his testis, ultrasonography revealed multiple low echoic lesions in his right testicular parenchyma. He was diagnosed with right testicular cancer with retroperitoneal lymph node metastasis and underwent right high orchiectomy. A pathological examination revealed pure seminoma and no nonseminomatous components were found in the specimen. Three courses of induction systemic chemotherapy (cisplatin, etoposide, and bleomycin) normalized his serum alpha-fetoprotein and DUPAN-2 levels. Three additional courses of chemotherapy (etoposide and bleomycin) were performed, and treatment was completed with laparoscopic retroperitoneal lymph node dissection. Pathology of the dissected specimen showed fibrous and necrotic tissue with no viable cells. He is alive without recurrence 54 months after orchiectomy.ConclusionsWe report a case of pure testicular seminoma with elevated serum alpha-fetoprotein and DUPAN-2 presenting retroperitoneal metastasis. We recommend an ultrasound examination of bilateral testes when large retroperitoneal tumors are detected in young men, even if a mass is not palpable in the scrotum.


Archivio Italiano di Urologia e Andrologia | 2016

Primary pure carcinoid tumour of the testis: A case report and review of the literature

Hideki Takada; Shoichiro Iwatsuki; Yasunori Itoh; Shinya Sato; Masa Hayase; Takahiro Yasui

Primary testicular carcinoid tumours (TCT) are very rare, and a large tumour size and the presence of carcinoid syndrome predict a malignant course. Histologically, it is difficult to differentiate between benign and malignant TCTs. We report a case of a primary pure TCT with an unusual presentation in a 23- year-old man, who had an asymptomatic, enlarged scrotum on the right side for 7 years. On gross examination, the tumour was 9.6 cm in diameter. The Ki-67 labelling index was 19.8%. High inguinal orchidectomy was performed, and 30 months after surgery the patient remains asymptomatic.


Urology | 2009

Detection of ectopic ureteral insertion to vagina with hypoplastic ectopic kidney by three-dimensional computed tomography.

Shoichiro Iwatsuki; Yoshiyuki Kojima; Makoto Imura; Kentaro Mizuno; Kenjiro Kohri; Yutaro Hayashi

A 3-year-old girl presented with constant urinary dribbling. 3D-CT imaging clearly demonstrated the left hypoplastic ectopic kidney and vaginal insertion of a single ureter. Left kidney contributed 1.6% of total renal function. She was diagnosed as having a left hypoplastic ectopic kidney with ectopic ureter draining into the vagina, and laparoscopic nephrouretectomy was performed. Although some imaging modalities rarely show ectopic insertion of the ureter, 3D-CT imaging can accurately depict both hypoplastic ectopic kidney and ectopic ureteral insertion, and improve the visualization of these structures as well as delineating the relationship among the ureter, bladder and vagina.


The Journal of Urology | 2018

MP60-09 DECREASED EXPRESSION OF P-TYPE ATPASES DURING PUBERTY IN RAT CRYPTORCHID TESTES AND ITS RELATION TO THERMAL ENVIRONMENTS

Shoichiro Iwatsuki; Yukihiro Umemoto; Tomoki Takeda; Satoshi Nozaki; Takahiro Yasui

METHODS: Two men with non-mosaic KS and azoospermia underwent microTESE. The SFTs were divided into DSFTs or CSFTs under the operating microscope at the time of surgery. Single cell suspensions were prepared from the DSFTs and CSFTs followed by preparation of libraries for single cell sequencing with 10X Genomics chromium system. Reads were aligned with STAR aligner, normalized with Limma, and analyzed with Seurat v2.0. Single tubules were stained with antibodies against UTF1 and SOX9. RESULTS: 20,207 reads were mapped for each specimen to GRCh38. Markers of SSCs and differentiating spermatogonia (SPG) such as ITGA6, GFRa1, SOHLH2, ENO2, ZBTB16, UCHL1, NEUROG3, OCT4, UTF1, SALL4, CDH1, BCL6B, KIT, ID4 and SOX2/3 were identified in both DSFTs and CSFTs from patients with KS and expressed at similar levels. Thus, indicating that SPGs and SSCs are present in both DSFTs and CSFTs in similar numbers along the SFTs. Presence of SSCs along the SFTs in KS was confirmed with antibody against UTF1 and GFRa1 and normalized to number of Sertoli cells using SOX9. There were statistically significant differences in expression of markers of fibrosis, lymphoand angiogenesis as well as makers involved in Sertoli to SSCs signaling; thus, confirming that rescue of KS is a result of rare events in which SSCs are exposed to optimal spermatogenic niche and are able to lose the additional X ch. CONCLUSIONS: Using single cell sequencing and immunofluorescence we uncovered that existence of optimal spermatogenic niche is critical for biologically occurring rescue of the 47,XXY in some rare areas of SFTs. These findings support our further effort into high resolution 4D analysis along SFTs to pinpoint critical levels of ligands and receptors necessary for KS rescue.

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