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We investigated the efficacy of dutasteride add-on therapy to α-1 adrenoceptor antagonists in patients with benign prostate hyperplasia (BPH) in relation to the transitional zone index (TZI) and evaluated the cutoff value of TZI that predicted improvements of subjective symptoms at 6 months.Male BPH patients with prostate volume (PV) ≥ 30 mL receiving dutasteride 0.5 mg/d for 6 months as add-on therapy along with α-1 adrenoceptor antagonists were enrolled. PV, transitional zone volume (TZV), TZI, International Prostate Symptom Score (IPSS), and uroflowmetry parameters before and at 6 months with dutasteride add-on treatment were evaluated.Eighty-three patients were included. The changes of total IPSS, IPSS voiding subscore, IPSS quality of life score, and voided volume were significantly correlated with TZI. Among baseline parameters, TZV and TZI were significantly associated with the changes of total IPSS in univariate analysis, and only TZI remained as an independent predictive factor for improving total IPSS in multivariate analysis (odds ratio -8.3, P = .048). The cutoff point of TZI for predicting an improvement of the total IPSS by 6 points or more was 0.67 (area under the curve 0.71, sensitivity 0.62, specificity 0.79).A higher TZI was significantly associated with improvement of subjective symptoms but not uroflowmetric findings for BPH patients with 6 months of dutasteride add-on therapy along with α-1 adrenoceptor antagonists, and the predictive value of TZI for effective dutasteride add-on therapy was higher than 0.67. BPH patients using α-1 adrenoceptor antagonists with a TZI higher than 0.67 can be good candidates for add-on dutasteride therapy.

This study aimed to evaluate whether it is useful for junior physicians to use a three-dimensional (3D) kidney model when evaluating the R.E.N.A.L. nephrometry score.An expert and four urology residents retrospectively evaluated the R.E.N.A.L. nephrometry scores of 64 renal tumors (62 patients) that underwent robot-assisted partial nephrectomy at our hospital. The expert evaluated 64 R.E.N.A.L. nephrometry scores with computed tomography (CT), whereas four residents evaluated 32 cases using CT alone and the other 32 cases using CT and a 3D kidney model. The consistency between the expert and residents was assessed by Cohen's kappa score. Patient-specific 3D kidney models were created in a gird style using a 3D printer based on CT or magnetic resonance imaging of the patient.For all four residents, the accuracy of the overall R.E.N.A.L. nephrometry score was significantly higher with the 3D model and CT than with CT alone (P .001). Regarding the individual components of the R.E.N.A.L. nephrometry score, the accuracy rates of "E," "N," "A," and "L" scores were higher with the 3D model and CT than with the CT alone (P = .020-.089).Patient-specific 3D-printed kidney models could improve the resident's understanding of the renal tumor complexity and could be an important educational tool for residents.

Lions (Panthera leo) breed well under captivity, so contraception has been commonly conducted for population management, leading to a demand for a less invasive and reversible contraceptive approach in lions. In this study, we examined the efficacy of a commercial gonadotropin-releasing hormone vaccine as a method of suppressing reproductive activity in a sexually matured female lion. Under behavioral restraint, the vaccine was injected twice (days 0 and 109). After the initial vaccination, ovarian activity is still observed. After the second vaccination, contraceptive effect was confirmed for 246 days until restart of estrous cycles. We confirmed only a slight swelling around the injection site after the second vaccination. This study may suggest an alternative option for a contraceptive method in lions.

We retrospectively compared the post-transplantation graft survival and the donor's estimated glomerular filtration rates (eGFRs) following living donor kidney transplantations (LDKTs) involving medically complex living donors (MCLDs) (the elderly and patients with obesity, hypertension, diabetes mellitus, or reduced renal function) and standard living donors (SLDs). The clinical data on patients who underwent LDKTs at our institution from 2006-2019, including 192 SLDs and 99 MCLDs, were evaluated. Regarding recipients, the log-rank test and multivariable Cox proportional hazards analyses showed a higher incidence of overall and death-censored graft loss in the recipients who received kidneys from MCLDs (Hazard ratio = 2.16 and 3.25, P = 0.015 and 0.004, respectively), after adjusting for recipient-related variables including age, sex, duration of dialysis, ABO compatibility, and donor-specific antibody positivity. Regarding donors, a linear mixed model showed significantly lower postdonation eGFRs (-2.25 ml/min/1.73 m2 , P = 0.048) at baseline in MCLDs than SLDs, but comparable change (difference = 0.01 ml/min/1.73 m2 /year, P = 0.97). In conclusion, although kidneys from MCLDs are associated with impaired graft survival, the donation did not adversely affect the MCLDs' renal health in at least the short-term. LDKTs involving carefully selected MCLDs would be an acceptable alternative for recipients with no SLDs.

The purpose of this study is to clarify the safety and efficacy of indigo carmine dye–assisted lymphatic-sparing microsurgical subinguinal varicocelectomy for children and adolescents in our institution. Medical records of boys aged ≤ 15 years who underwent varicocelectomy between November 2008 and December 2019 at our institution were retrospectively reviewed. Microsurgical subinguinal varicocelectomy was performed using indigo carmine injection under the tunica vaginalis to preserve lymphatics. A total of 29 patients underwent varicocelectomy, among whom six underwent retroperitoneal high ligation (modified Palomo technique), nine underwent laparoscopic varicocelectomy, and 14 underwent microsurgical subinguinal varicocelectomy. The median operative time for retroperitoneal high ligation, laparoscopic varicocelectomy, and microsurgical subinguinal varicocelectomy was 71 (IQR: 59–82.5) min, 131 (95–151) min, and 125.5 (112–134.25) min, respectively. Among the patients who underwent laparoscopic varicocelectomy, one and two experienced hydrocele and varicocele recurrence as postoperative complications, respectively. None of the patients who underwent microsurgical subinguinal varicocelectomy developed hydrocele and varicocele recurrence during 15.5-month median follow-up period (IQR: 11.25–25.75 month). Indigo carmine dye–assisted lymphatic-sparing microsurgical subinguinal varicocelectomy can be a safe and efficient treatment modality among children and adolescents.

INTRODUCTION AND OBJECTIVE:Prostate cancer is a malignant tumor that most commonly occurs in men. In Japan, 91,215 men developed prostate cancer in 2017. Among all carcinomas, the number of patient...

Background: Delayed postoperative bleeding after robot-assisted radical prostatectomy (RARP) is a rare life-threatening condition. We present such a case wherein a patient developed hemorrhagic shock from a ruptured pseudoaneurysm arising from the epigastric artery and discuss its management. Case Presentation: A 71-year-old man with prostate cancer underwent RARP. The urethral catheter was removed on postoperative day 7; 80 minutes later, the patient suddenly lost consciousness and went into shock. Enhanced CT revealed intra-abdominal bleeding; however, the cause was unknown. Intraoperatively, bleeding was observed from the anterior abdominal wall, which likely corresponded to the epigastric artery. However, this was controlled with monopolar electrocautery. Because of unstable hemodynamics, hemostasis was immediately performed by laparotomy, and bleeding was noted from the previously coagulated right inferior epigastric artery. Therefore, the cause was considered to be the rupture of a pseudoaneurysm. Conclusion: Our experience suggests that monopolar electrocautery may be inadequate for controlling bleeding that may be encountered during RARP, possibly leading to pseudoaneurysm formation, which may cause a delayed life-threatening hemorrhage. Meticulous and precise hemostasis is key to avoiding this complication.

INTRODUCTION To clarify the safety and efficacy of en bloc simultaneous robot-assisted radical cystectomy (RARC) and laparoscopic nephroureterectomy (LNU) for synchronous muscle-invasive bladder carcinoma and upper tract urothelial carcinoma (UTUC) or UTUC of a solitary kidney, we evaluated the perioperative and short-term outcomes of this surgical procedure compared with those of simultaneous open radical cystectomy and nephroureterectomy. METHODS We prospectively enrolled consecutive patients receiving en bloc simultaneous RARC and LNU between December 2018 and March 2020 at two institutes. Patients' characteristics, surgical, perioperative, and pathological outcomes and recurrence rate within 6 months were compared with a historical control receiving simultaneous open radical cystectomy and nephroureterectomy. RESULTS Ten patients receiving simultaneous RARC and LNU and 17 receiving simultaneous open radical cystectomy and nephroureterectomy were included in the study. Simultaneous RARC and LNU significantly reduced bleeding volume and blood transfusion (P

Objectives To assess the relationship between the surgical procedure of robot‐assisted radical prostatectomy (RARP) and urinary continence recovery by reviewing the video database. Methods Video and data about men diagnosed with prostate cancer and underwent RARP were extracted and reviewed. Preserved urethral length (PUL) was semi‐quantitatively measured using the lateral width of a 16‐Fr urethral balloon catheter while cutting the urethra on a video screen. In addition, by reviewing intraoperative RARP video database, other surgical skill outcomes were also collected. Kaplan–Meier analysis with log‐rank test was used to compare the urinary continence recovery rate, stratified by the PUL. Univariate and multivariate analyses were performed using the Cox proportional hazards model, and p‐values of

In cuprate superconductors, superconductivity appears below the CDW transition temperature $T_{CDW}$. However, many-body electronic states under the CDW order are still far from understood. Here, we study the development of the spin fluctuations under the presence of $d$-wave bond order (BO) with wavevector $q=(\pi/2,0),(0,\pi/2)$, which is derived from the paramagnon interference mechanism in recent theoretical studies. Based on the $4 \times 1$ and $4 \times 4$ cluster Hubbard models, the feedback effects between spin susceptibility and self-energy are calculated self-consistently by using the fluctuation-exchange (FLEX) approximation. It is found that the $d$-wave BO leads to a sizable suppression of the nuclear magnetic relaxation rate $1/T_1$. In contrast, the reduction in $T_c$ is small, since the static susceptibility $\chi^s(Q_s)$ is affected by the BO just slightly. It is verified that the $d$-wave BO scenario is consistent with the experimental electronic properties below $T_{CDW}$., Comment: 8 pages,7 figures, to be published in J. Phys. Soc. Jpn

BACKGROUND: We assessed the natural history of renal artery pseudoaneurysm (RAP) after robot-assisted partial nephrectomy (RAPN). METHODS: From May 2016 to September 2020, 106 patients underwent RAPN for renal tumors at our institution. Among 100 patients, excluding 6 who were ineligible for contrast-enhanced computed tomography (CE-CT), 4 underwent renal artery selective embolization (RAE), of which 2 cases were emergency RAE within 7 days after RAPN and the other 2 were prophylactic RAE 8 or more days after RAPN. In 98 patients examined for the clinical course of asymptomatic RAP managed by surveillance, excluding the 2 who underwent emergency RAE, routine CE-CT was performed at 7 days, 1 month and 3 months after RAPN. Factors influencing the occurrence of RAP among these 98 patients, including the 2 who underwent emergency RAE and excluding the 2 who underwent prophylactic RAE, were analyzed by logistic regression analysis. RESULTS: Median [interquartile range (IOR), range] observation period, age, radiographic tumor size, and maximum diameter of RAP were 20.8 (23.9, 3.0–57.6) months, 63 (18, 22–84) years, 23 (11, 9–48) mm, and 6.6 (5.2, 3.0–16.0) mm, respectively. CE-CT detected 28 RAPs in 23 (23.0%) of 100 patients by 7 days after RAPN and routine CE-CT detected 25 RAPs in 21 (21.4%) of 98 patients excluding 2 who underwent emergency RAE at 7 days after RAPN. RAP was diagnosed by routine CE-CT in 21 (21.4%), 1 (1.0%), and 0 (0%) patients at 7 days, 1 month, and 3 months after RAPN, respectively. In univariate analysis, age [odds ratio (OR) 0.144: 69–84 vs. 22–56 years old, P=0.0179], R.E.N.A.L [radius (tumor size as maximal diameter), exophytic/endophytic properties of tumor, nearness of tumor deepest portion to collecting system or sinus, anterior/posterior descriptor and location relative to polar line] nephrometry score (OR 1.374, P=0.0382), warm ischemic time (OR 1.085, P=0.0393), and renorrhaphy time (OR 1.055, P=0.0408) were significantly associated with the occurrence of RAP. In multivariate analysis, only age (OR 0.124, P=0.0148) was a significant factor. CONCLUSIONS: Asymptomatic RAP up to 15 mm in diameter resolved spontaneously 3 months after RAPN. Young age (under 56 years) may be a factor in the development of RAP.

Objectives To evaluate thermal denaturation depth using soft coagulation in kidneys in vivo. Methods In experiment 1, nine kidneys from five pigs were cauterized using five soft-coagulation settings at 80 W with effect 7 by VIO300D and one monopolar-coagulation setting. The surface of the kidney was cauterized over a period of 2, 5 and 10 s. The temperature change was measured at depths of 5 and 10 mm. In experiment 2, three kidneys from two pigs were excised in a semicircular shape with a diameter of 5, 10 and 20 mm without clamping the renal artery. Cauterization was carried out until hemostasis was confirmed by soft coagulation at 80 W with effect 7. After completion of the experiments, pathology examinations of the kidneys were carried out. Results Experiment 1 showed that with proper saline dripping, denaturation spread with increased cauterization time, reaching a depth of 4 mm at 10 s with or without clamps. The depth remained at 2-3 mm at 10 s in the absence or excess of saline. The temperature increased by 15.6°C at a depth of 5 mm and 8.8°C at 10 mm. In experiment 2, the depth was 4.6 mm from the incision surface regardless of the cauterization time or excision size. Conclusions These findings suggest that soft coagulation can be useful for preserving renal function and reducing complications in partial nephrectomy.

We propose a construction and calibration method of an absolute coordinate system for lithography tools. In the conventional overlay control system, subsequent layers are overlaid on the 1st layer that could have unknown wafer distortion. This is inefficient, because the distortion of the 1st layer may be large. A high-level overlay control can be realized with the absolute coordinate system by correcting the 1st layer to zero distortion. This can be possible by using absolute alignment metrology system. In order to confirm our theory, we report experimental results of the absolute grid construction and matching accuracy among multiple lithography tools.

BACKGROUND: This retrospective study aimed to investigate whether a three-dimensional (3D) model would improve the achievement of TRIFECTA, which was defined as the absence of perioperative complications and positive surgical margins and a warm ischemia time of

OBJECTIVE: A prospective questionnaire survey was conducted for patients with benign prostatic hyperplasia (BPH) to clarify seasonal changes in the lower urinary tract symptoms (LUTS). MATERIAL AND METHODS: Male patients receiving α1-adrenoreceptor antagonists for BPH were enrolled. They answered the International Prostate Symptom Score (IPSS) questionnaire, and an unvalidated questionnaire that consisted of 10 questions assessing variations in the urinary stream (voiding symptoms) and urinary frequency (storage symptoms), depending upon the seasons or the patients’ subjective sensations of warm and cold in last one year. RESULTS: A total of 412 participants answered IPSS and our unvalidated questionnaire. Of the 412 participants, 36.7% and 59.0% realized seasonal variations in urinary stream and frequency, respectively. Among patients perceiving seasonal urinary stream and urinary frequency changes (n=151 and n=243, respectively), significantly more patients realized weaker urinary stream, 59.8% (107/179) in winter compared with 26.2% (47/179) in summer, and increased urinary frequency, 69.8% (199/285) in winter compared with 20.7% (59/285) in summer (p

Background The R.E.N.A.L. nephrometry scoring system is used to evaluate the complexity of renal tumors; however, inconsistency among evaluators, especially junior physicians, is an issue. The objective of the study was to evaluate whether it is useful for junior physicians to use a three-dimensional (3D) kidney model when evaluating the R.E.N.A.L. nephrometry score. Methods An expert and four urology residents retrospectively evaluated the R.E.N.A.L. nephrometry scores of 64 renal tumors (62 patients) which underwent robot-assisted partial nephrectomy at our hospital. The expert evaluated 64 R.E.N.A.L. nephrometry scores with computed tomography (CT) scan imaging, while four residents evaluated 32 cases using only CT and the other 32 cases using CT and 3D kidney model. Consistency between the expert and residents was assessed by Cohen’s kappa score. Patient-specific 3D kidney models were created in a gird style using a 3D printer based on the CT or magnetic resonance imaging of the patient. Results For all four residents, the accuracy of the overall R.E.N.A.L. nephrometry score was significantly higher by 3D model and CT than CT only (p

Background and Aims Evidence demonstrating the outcomes of living donor kidney transplantation (LDKT) from marginal donors (MDs) is limited. We retrospectively investigated the clinical outcomes of LDKT from MDs in both recipients and donors. Method Clinical data on patients who received LDKT in Jichi Medical University Hospital between 2006 and 2019 were extracted from the medical records. Based on the Japanese guideline for preoperative conditions of donors, they were classified as standard donors (SDs) or MDs, the latter including the elderly and patients with obesity, hypertension, diabetes mellitus, and reduced renal function. Multivariate Cox proportional hazard regression analysis for graft survival was performed using explanatory variables of the donor conditions (MD vs SD) and recipient conditions, including age, gender, duration of dialysis, ABO compatibility, and presence of donor specific antibodies. The estimated glomerular filtration rates (eGFRs) of the donors were compared using an unpaired t-test. Results Of the 293 donors, 195 were SDs and 98 were MDs. Demographics and baseline characteristics of recipients and donors Recipients of kidney transplants from MDs were associated with a higher incidence of death-censored graft loss than recipients of kidney transplants from SDs. Kaplan-Meier plots for overall and death-censored graft survival. Multivariate Cox proportional hazard regression analyses for overall and death-censored graft survival The eGFRs of MDs before transplantation were significantly lower than those of SDs, while no significant differences were observed between the two groups 3- and 5-years after transplantation. Comparison of estimated glomerular filtration rates of donors Conclusion While the renal prognosis of recipients of kidneys from MDs is poorer than that of recipients from SDs, donating a kidney has no adverse effects on the renal health of MDs. The present study is the most comprehensive study that examined that the outcomes of LDKT from MDs according to the Japanese guideline.

Transvaginal cervicoisthmic cerclage was carried out in 12 such patients who were at high-risk of premature delivery. Patients who underwent transvaginal cervicoisthmic cerclage had undergone conization, cervical radical hysterectomy or another form of extensive cervical resection, or had a history of third-trimester miscarriage or premature delivery despite having previously undergone cervical cerclage several times for cervical incompetence. There were seven cases of pregnancy after extensive conization, and four had a history of failed cervical cerclage. Two of these cases were the same individual, who became pregnant twice after extensive conization and gave birth to a live infant each time. The mean age at surgery was 35.7 years, and cerclage was performed at 11-19 weeks' gestation. All of the infants survived to hospital discharge. Transvaginal cervicoisthmic cerclage may be considered effective for patients with the history of recurring pregnancy loss due to previous failure of prophylactic cerclage.

One-(2-18F-fluoro-1-(hydroxymethyl)ethoxy) methyl-2-nitroimidazole (18F-FRP170) is a marker of hypoxic but viable tissue in the human brain and is used in positron emission tomography (PET).1 Neural tissues showing elevated 18F-FRP170 uptake exist in brain areas with chronic cerebral ischaemia with a combination of increased oxygen extraction fraction, namely misery perfusion and moderately reduced cerebral metabolic rate of oxygen (CMRO2) due to atherosclerotic stenosis or occlusion of the internal carotid artery.1 These hypoxic neural tissues decrease after cerebral perfusion and restored following carotid endarterectomy, leading to postoperative cognitive improvement after surgery.2 Adults with ischaemic moyamoya disease (MMD) sometimes experience cognitive improvement after revascularisation surgery.3 The present prospective study was aimed to determine whether the resolution of hypoxia in neural tissue and recovery of cerebral oxygen metabolism on PET after revascularisation surgery such as a combination of the superficial temporal artery–middle cerebral artery anastomosis and encephalo-duro-myo-synangiosis are related to postoperatively improved cognition in adults with ischaemic MMD. Patients with the following criteria were prospectively included in this study: (1) bilateral MMD confirmed by angiography via arterial catheterisation; (2) histories of ischaemic symptoms in unilateral carotid artery territory ≤3 months before visiting our hospital; (3) ≥30 years and

Some chemicals are harmful in to light-exposed tissues such as skin and eyes. The 3T3 Neutral Red Uptake Phototoxicity Test has been validated and adopted by the Organization of Economic and Community Development (OECD) as a method of evaluating chemical phototoxicity using mouse 3T3 fibroblasts. However, the high rate of false positive results associated with this test eventually led to increased laboratory animal usage. Although the eye is vulnerable to light damage because of constant exposure to environmental radiation, few approaches are available to predict ocular phototoxicity in humans. Here, we propose a tier one test that identifies the potential ocular phototoxicity of chemical substances. Using a three-dimensional culture technique, human embryonic stem cells (hESCs) were differentiated to retinal pigment epithelial cell (RPE) precursors. The precursors after prolonged treatment with FBS formed a uniform hexagonal lattice of cells with well-developed tight junctions and time-dependent elevation of melanin content and RPE maturation marker levels. Hierarchical clustering of gene transcripts revealed that hESC-derived RPEs were very similar to tissue-derived adult RPEs. Interestingly, there were a high percentage of chemicals eliciting a positive response in 3T3 cells and negative in hESC-derived RPEs under the experimental conditions used in the phototoxicity test. The response to treatment of hESC-derived RPEs with these negative chemicals became positive at a higher dose of UVA irradiation; however, the biological responses to these chemicals differed between the two cells. Taken together, we conclude that hESC-derived RPEs are novel tool for future toxicological and mechanistic studies of ocular phototoxicity in humans.

Aim To evaluate predictive factors which associated with oncological outcomes to first-line axitinib for metastatic renal cell carcinoma (mRCC). Methods A retrospective chart review was conducted patients who had been treated with axitinib as first-line therapy for the treatment of mRCC from September 2013 to February 2018. Axitinib was given by single daily oral administration at a dose of 10 mg, which was reduced according to adverse events (AEs). We investigated progression-free survival (PFS), overall survival (OS), objective response rate (ORR) and AEs. Results Thirty-eight mRCC patients were enrolled. The median follow-up duration of axitinib treatment was 11.3 months (range = 1.0-56.9). ORR was 28.9%. Median PFS and OS was 12.8, and 17.9 months, respectively. In univariate analysis, baseline lactate dehydrogenase (LDH), neutrophil, corrected calcium (Ca), platelets (Plt) and time from diagnosis were selected as potential predictive factors. Multivariate Cox's proportional hazards model analysis showed that the number of risk factors were associated with PFS (P = 0.03) and OS (P = 0.02). Conclusion Baseline LDH, neutrophil, Ca, Plt and time from diagnosis are predictive factors for both PFS and OS in first-line treatment with axitinib for metastatic renal cell carcinoma.

Objectives The efficacy and safety of sunitinib versus sorafenib in patients with advanced renal cell carcinoma with renal impairment remains poorly documented. Patients and methods We assessed the efficacy and safety of sunitinib and sorafenib in patients with advanced renal cell carcinoma with an estimated glomerular filtration rate of 15–60 mL/min/1.73 m2 by reviewing the medical records of patients treated at Jichi Medical University Hospital, Japan, between May 2008 and August 2016. Results Twenty-seven patients were treated with sunitinib and 14 with sorafenib. Median progression-free survival in sunitinib- and sorafenib-treated patients was comparable, at 6.6 vs 5.8 months, respectively (HR, 1.618; 95% CI, 0.689–3.798; P = 0.2691). Median overall survival was also comparable, at 65.9 vs 58.0 months (HR, 0.985; 95% CI, 0.389–2.479; P = 0.9748). Grade 3 or higher adverse events were significantly more frequent in the sunitinib-treated than sorafenib-treated patients (P = 0.0357). Compared to pre-treatment values, estimated glomerular filtration rate at the discontinuation of treatment was not decreased in either group. In contrast, estimated glomerular filtration rate was decreased on long-term treatment, particularly in previously nephrectomized patients. Conclusions Sunitinib and sorafenib had similar efficacy in patients with advanced renal cell carcinoma and severe renal impairment. Although renal function was not markedly impaired in either group, close attention to decreased renal function may be necessary in previously nephrectomized patients on long-term treatment.

A standalone alignment technology was developed as a fundamental solution to improve on-product overlay (OPO). It enables high performance alignment measurements, and delivers state-of-the-art feed-forward corrections to exposure scanners. Dense alignment sampling and high order alignment correction is effective for scanner fingerprint matching and for correcting heavy distortion at a wafer edge. A mark asymmetry correction is detailed as effective solution which improves the OPO performance for heavily processed wafers. An OPO test result showed significant improvement using its feed-forward corrections. A high accuracy topography sensor is described as a new metrology innovation. The standalone alignment technology provides critical metrology tool functions such as process monitoring as well.

Objective DNA methyltransferase 3-like plays an important role in germ cell development. The aim of this study was to analyse the DNA methyltransferase 3-like protein expression in testicular germ cell tumors. Methods The immunohistochemical expression of DNA methyltransferase 3-like was examined in 86 testicular germ cell tumor specimens in various clinical settings. The association between DNA methyltransferase 3-like expression and disease stage was analyzed. Results DNA methyltransferase 3-like was strongly expressed in seven of the eight pure embryonal carcinomas (87.5%). Partial DNA methyltransferase 3-like expression was observed in 6 of 23 (26.1%) pure seminomas. Various degrees of DNA methyltransferase 3-like expression was observed in all four pure yolk sac tumors, of which three were prepubertal yolk sac tumors. In mixed germ cell tumors, DNA methyltransferase 3-like protein was expressed in various degrees in elements of the embryonal carcinoma (14/18, 77.8%), seminoma (4/11, 36.4%), teratoma (4/7, 57.1%) and choriocarcinoma (3/3, 100%) but not in the yolk sac tumors (0/4). When DNA methyltransferase 3-like expression was analyzed according to disease stages, it was significantly correlated with advanced seminoma rather than Stage I seminoma (46.2 vs. 0%, P = 0.019), whereas there was no significant difference in the DNA methyltransferase 3-like-positive proportion between Stage I and advanced disease in the mixed germ cell tumors. Conclusions Our findings suggest that DNA methyltransferase 3-like protein may play roles not only in the development of embryonal carcinoma but also in the development of advanced pure seminoma and pure yolk sac tumor.