Development of a deep-learning model for detecting positive tubules during sperm recovery for nonobstructive azoospermia.

To enhance surgical testicular sperm retrieval outcome for men with nonobstructive azoospermia, a deep-learning model was developed to identify positive seminiferous tubules by labeling 110 images with sperm-containing tubules sampled during microdissection testicular sperm extraction as training and validation data. After training, the model achieved an average precision of 0.60.

Out-of-pocket fertility preservation expenses: data from a Japanese nationwide multicenter survey.

BACKGROUND: The expenses related to fertility preservation or subsequent assisted reproductive treatments are significant for adolescents and young adult patients in Japan's current healthcare system. With fertility preservation becoming more widespread in developed countries, it is expected that these costs will be covered by insurance or subsidies. It is critical for patients, healthcare providers, and the government to know the costs that patients will be responsible for. In Japan, the costs of fertility preservation and subsequent assisted reproductive technology are not covered by insurance, but patients can apply for subsidies from the local and central governments if certain conditions are met. Presently, the above-mentioned costs, as well as the amount paid by the patient, vary by facility. Therefore, it is essential to ensure patients' continued access to necessary medical care despite the associated costs. METHODS: In this study, questionnaires were mailed to 186 certified fertility preservation facilities in Japan to assess patients who had undergone fertility preservation or assisted reproduction. The questionnaires were sent between October 27, 2023 and March 31, 2024, with 140 of the 186 facilities responding (response rate: 75.3%). RESULTS: Our findings show that approximately one-third of the costs was borne by the patients. CONCLUSION: Given these circumstances, sustainable pricing and insurance coverage are necessary for both patients and facilities.

Clinical management of nonobstructive azoospermia: An update.

Approximately 1% of the general male population has azoospermia, and nonobstructive azoospermia accounts for the majority of cases. The causes vary widely, including chromosomal and genetic abnormalities, varicocele, drug-induced causes, and gonadotropin deficiency; however, the cause is often unknown. In azoospermia caused by hypogonadotropic hypogonadism, gonadotropin replacement therapy can be expected to produce sperm in the ejaculate. In some cases, upfront varicocelectomy for nonobstructive azoospermia with varicocele may result in the appearance of ejaculated spermatozoa; however, the appropriate indication should be selected. Each guideline recommends microdissection testicular sperm extraction for nonobstructive azoospermia in terms of successful sperm retrieval and avoidance of complications. Sperm retrieval rates generally ranged from 20% to 70% but vary depending on the causative disease. Various attempts have been made to predict sperm retrieval and improve sperm retrieval rates; however, the evidence is insufficient. Further evidence accumulation is needed for salvage treatment in cases of failed sperm retrieval. In Japan, there is inadequate provision on the right to know the origin of children born from artificial insemination of donated sperm and the rights of sperm donors, as well as information on unrelated family members, and the development of these systems is challenging. In the future, it is hoped that the pathogenesis of nonobstructive azoospermia with an unknown cause will be elucidated and that technology for omics technologies, human spermatogenesis using pluripotent cells, and organ culture methods will be developed.

Effect of a web-based fertility preservation training program for medical professionals in Japan.

BACKGROUND: Our web-based training program called "Educating Medical Professionals about Reproductive Issues in Cancer Healthcare" aims to help healthcare professionals communicate promptly with patients and survivors who are adolescents and young adults, with information pertinent to reproductive health issues such as the risk of infertility and fertility preservation. METHODS: The study participants were professional healthcare providers, including physicians, nurses, pharmacists, social workers, midwives, psychologists, laboratory technicians, genetic counselors, and dieticians. Pre- and post- and 3-month follow-up tests consisting of 41 questions were administered to measure changes in knowledge and confidence. The participants also received a follow-up survey that covered confidence, communication techniques, and practice habits. A total of 820 healthcare providers participated in this program. RESULTS: The mean total score from the pre-test to the post-test grew significantly (p < 0.01), and participants' self-confidence increased. In addition, there was a change in the behavior of healthcare providers, who began asking about patients' marital status and parity. CONCLUSION: Our web-based fertility preservation training program improved knowledge and self-confidence regarding fertility preservation issues among healthcare providers caring for adolescents and young adult cancer patients and survivors.

Sperm DNA fragmentation testing in clinical management of reproductive medicine.

Background: Approximately 8%-12% of couples worldwide face infertility, with infertility of individuals assigned male at birth (AMAB) contributing to at least 50% of cases. Conventional semen analysis commonly used to detect sperm abnormalities is insufficient, as 30% of AMAB patients experiencing infertility show normal results in this test. From a genetic perspective, the assessment of sperm DNA fragmentation (SDF) is important as a parameter of sperm quality. Methods: In this narrative study, we review and discuss pathophysiological causes, DNA repair mechanisms, and management of high SDF. We then summarize literature exploring the association between SDF and reproductive outcomes. Main Findings: Recent systematic reviews and meta-analyses have revealed a significant association between high SDF in AMAB individuals and adverse reproductive outcomes including embryo development, natural conception, intrauterine insemination, and in vitro fertilization. However, the association with live birth rates and pregnancy rates following intracytoplasmic injection remains inconclusive. The disparities among quantitative assays, inconsistent reference range values, absent high-quality prospective clinical trials, and clinical heterogeneity in AMAB patients with elevated SDF represent the main limitations affecting SDF testing. Conclusion: The evaluation and management of SDF plays an important role in a subset of AMAB infertility, but widespread integration into clinical guidelines will require future high-quality clinical trials and assay standardization.

Monozygotic adult twins with nonmosaic Klinefelter syndrome with different results of sperm retrieval.

Klinefelter syndrome and monozygotic twins are both rare. The reports of monozygotic twins with Klinefelter syndrome to have undergone fertility treatment are uncommon. This case report describes a case of 30-year-old monozygotic adult twin brothers diagnosed with nonmosaic Klinefelter syndrome following the complaint of infertility. The result of semen analysis showed cryptozoospermia (very low sperm count) and azoospermia (zero sperm count) with physical findings and lifestyles being very similar. They both underwent microtesticular sperm extraction. One had successful sperm retrieval and achieved pregnancy through intracytoplasmic sperm injection, whereas the other did not. Testicular pathological findings showed Sertoli cell-only syndrome. To the best of our knowledge, this is the first report on monozygotic adult twins both of whom underwent microtesticular sperm extraction and resulted in different outcomes.

A practical survey of fertility-preservation treatments in the startup phase in Japan.

AIM: The actual status of fertility preservation treatments in the startup phase in Japan was investigated as a basis for discussing future directions. METHODS: This study was conducted as "Research project to promote support of children and parenting 2016" which was supported by Ministry of Health in Japan with the approval of the institutional review board at St. Marianna University. Subjects of the survey were facilities registered with the Japan Society of Obstetrics and Gynecology as fertility preservation facilities, and facilities belonging to the Japan Association of Private Assisted Reproductive Technology Clinics and Laboratories. We provided questionnaires to survey both the medical care system and cases for which fertility preservation was implemented between 2006 and 2016. RESULTS: Responses were obtained from 68 facilities (of the 64, 59 [92.2%] responded to the questionnaire and 9 clinics cooperated). Many facilities limited the cryopreservation of oocytes and ovaries to patients 40-41 years old and the use of eggs to patients 44-45 years old. In the patient survey, 812 cases of oocyte cryopreservation and 201 cases of ovarian tissue cryopreservation were performed during study period. Breast cancer was the most indicated disease, with oocyte cryopreservation in the late 30s and ovarian tissue cryopreservation in the early 30s. Very few babies were born from fertility preservation, and no live birth cases of ovarian tissue cryopreservation were identified. CONCLUSIONS: Even from the early days, fertility preservation was implemented according to certain standards in Japan, but was characterized by a large variety of facilities.

Effect of keishibukuryogan combined with tocopherol nicotinate on sperm parameters in patients with a varicocele.

OBJECTIVE: To evaluate the efficacy of keishibukuryogan, a traditional Kampo formula known to be an anti-Oketsu (impaired microcirculation and non-physiological blood congestion) drug, in combination with an anti-oxidant for the treatment of varicoceles. METHODS: We retrospectively analyzed 119 patients with palpable and subclinical varicoceles who were treated with 7.5 g/day of keishibukuryogan and 600 mg/day of tocopherol nicotinate. Their motile sperm concentrations at the start of medication and after 3 months were compared. As a subgroup analysis, a comparison test was carried out between patients with a high-grade varicocele and those with a low-grade varicocele. RESULTS: The mean age of the study patients was 35.6 years. Among them, 17, 41, 44 and 17 had subclinical, grade 1, grade 2 and grade 3 varicoceles, respectively. Overall, the differences in motile sperm concentration (millions/mL) before and after treatment were not significant (median 0.58, 95% confidence interval -0.12 to 1.56; P = 0.115). The results of the subgroup analysis showed that the motile sperm concentration in patients with a low-grade varicocele significantly increased (median 1.21, 95% confidence interval 0.45-2.47; P = 0.024); however, no significant improvements were seen in patients with a high-grade varicocele. CONCLUSIONS: The results of the present study showed that the combination of keishibukuryogan and an anti-oxidant had a limited effect on varicoceles, but they suggest that it is effective for the treatment of low-grade varicoceles.

Summary of the Clinical Practice Guidelines for Penile Cancer 2021 by the Japanese Urological Association.

Penile cancer is a rare cancer for which no medical guidelines have been established before in Japan. These guidelines aim to standardize, as much as possible, the therapeutic modality for penile cancer, for which empirical evidence is limited on a global scale, thereby bolstering therapeutic outcomes for patients with penile cancer. The new guidelines conform to the Minds Guide for Developing Clinical Practice Guidelines (2017) as much as possible. However, virtually no randomized comparative studies and meta-analyses based on such randomized studies have been conducted. Therefore, only the findings available at present were listed after conducting an exhaustive literature review of items with extremely low evidence levels and for which bodies of evidence and grades of recommendation were not evaluated. Clinical questions were set for items with a relatively large number of studies, including retrospective studies. However, since it is virtually impracticable to summarize bodies of evidence by systematic reviews, recommendation grades and evidence levels were discussed and determined by the consensus panel of the Preparatory Committee. The following were outlined: epidemiological, pathological, diagnostic, therapeutic, follow-up, and quality of life-related findings. Additionally, seven clinical questions were established to determine recommendation grades and evidence levels. We hope that these guidelines will prove to be useful to medical professionals engaged in clinical practice related to penile cancer in Japan and anticipate that critical reviews of the guidelines will lead to further refinement of the next edition.

Fertility and sexual dysfunction in young male cancer survivors.

Background: Newly emerging serious post-treatment complications among young male cancer survivors involve fertility and sexual function, preventing them from pursuing a normal family life. Methods: We studied and summarized published studies that assess the relationship between cancer treatments and reduced spermatogenesis or sexual dysfunction. Main findings: Infertility often occurs because of anticancer therapies that impair spermatogenesis. While some patients postremission functionally recover fertility, others experience a decreased sperm count and azoospermia. Fertility-preserving modalities are currently being promoted worldwide to preserve spermatogenesis following cancer therapy. Patients who can ejaculate and have sperm in their semen should cryopreserve semen. However, for patients who have never ejaculated before puberty or in whom spermatogenesis has not been established, testis biopsy is performed to collect and preserve sperm or germ cells. Fertility preservation is gaining popularity and requires continuous information dissemination to oncologists and cancer treatment professionals. Furthermore, male sexual dysfunction predominantly involves erectile dysfunction and ejaculation disorder. Conclusion: Although preventive and therapeutic methods for these disorders have been established within urology, patients and medical professionals in other fields remain uninformed of these advances. Therefore, dissemination of information regarding fertility preservation techniques should be accelerated.

Effects of antioxidant co-supplementation therapy on spermatogenesis dysfunction in relation to the basal oxidation-reduction potential levels in spermatozoa: A pilot study.

Purpose: In this pilot study, the authors compared the effects of antioxidant co-supplementation therapy and methylcobalamin therapy in patients with impaired semen quality. Methods: Eighty-four subjects who visited male infertility clinics and showed abnormal semen test results were randomly subjected to one of the two therapies: antioxidant co-supplementation therapy with vitamin C, vitamin E, coenzyme Q10, and flaxseed oil or methylcobalamin therapy. The oxidation-reduction potential (ORP) and 8-hydroxy-2'-deoxyguanosine levels were used as indicators of oxidative stress levels in semen. Semen analysis was also performed. Results: The authors obtained results from 67 patients who had completed 3 months of treatment. Neither antioxidant co-supplementation therapy nor methylcobalamin therapy changed the semen parameters significantly (except for the sperm concentration, which was increased by the latter therapy). When the pre-treatment ORP value in semen was higher than the cutoff value, both therapies significantly increased the sperm concentration. The 8-hydroxy-2'-deoxyguanosine level did not yield any meaningful predictive value with regard to increased sperm concentrations. Conclusions: Both antioxidant co-supplementation therapy and methylcobalamin therapy increased the sperm concentration in patients with impaired semen quality when the basal ORP levels in their semen were elevated.

Fertility preservation immediately after therapeutic abortion results in multiple normal follicular growth with the absence of mature oocytes due to early luteinization: a case report and literature review.

Cancer therapy has priority over fertility preservation. The time available for fertility preservation in patients with cancer is often very limited and depends on the condition of the underlying disease. This case report presents the results of two rounds of controlled ovarian stimulations (COSs) performed after an induced abortion. The patient had mixed phenotype acute leukemia diagnosed during early pregnancy and underwent a surgical abortion, followed by ovarian stimulation using urinary follicle-stimulating hormone (uFSH) and gonadotropin-releasing hormone (GnRH) agonists. Oocyte retrieval was subsequently performed for oocyte cryopreservation. Despite good hormonal and ultrasonic follicular growth, no oocytes were obtained. During a second COS performed at a low human chorionic gonadotropin (hCG) level (less than 100 IU/L), several mature oocytes were obtained, suggesting that higher hCG levels during COS induce the absence of mature oocytes during normal follicular growth. It is recommended to start COS post-abortion after confirming a low hCG level while considering the timing of cancer treatment.

Oxidative stress and male infertility.

BACKGROUND: Between 30% and 80% of patients with male infertility produce excessive reactive oxygen species (ROS) in their ejaculate even though the cause of male infertility is unexplained in approximately half of cases. The strong connection between oxidative stress (OS) and male infertility has led recent investigators to propose the term "Male Oxidative Stress Infertility (MOSI)" to describe OS-associated male infertility. METHODS: We searched the PubMed database for original and review articles to survey the effects of OS on male infertility, and then verified the effects and treatments. MAIN FINDINGS: Seminal plasma contains many antioxidants that protect sperm from ROS, because low amounts of ROS are required in the physiological fertilization process. The production of excessive ROS causes OS which can lower fertility through lipid peroxidation, sperm DNA damage, and apoptosis. Several assays are available for evaluating OS, including the MiOXSYS® analyzer to measure oxidation-reduction potential. Several measures should be considered for minimizing OS and improving clinical outcomes. CONCLUSION: Accurately diagnosing patients with MOSI and identifying highly sensitive biomarkers through proteomics technology is vital for better clinical outcomes.

BHD-associated kidney cancer exhibits unique molecular characteristics and a wide variety of variants in chromatin remodeling genes.

Birt-Hogg-Dubé (BHD) syndrome is a hereditary kidney cancer syndrome, which predisposes patients to develop kidney cancer, cutaneous fibrofolliculomas and pulmonary cysts. The responsible gene FLCN is a tumor suppressor for kidney cancer, which plays an important role in energy homeostasis through the regulation of mitochondrial oxidative metabolism. However, the process by which FLCN-deficiency leads to renal tumorigenesis is unclear. In order to clarify molecular pathogenesis of BHD-associated kidney cancer, we conducted whole-exome sequencing analysis using next-generation sequencing technology as well as metabolite analysis using liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. Whole-exome sequencing analysis of BHD-associated kidney cancer revealed that copy number variations of BHD-associated kidney cancer are considerably different from those already reported in sporadic cases. In somatic variant analysis, very few variants were commonly observed in BHD-associated kidney cancer; however, variants in chromatin remodeling genes were frequently observed in BHD-associated kidney cancer (17/29 tumors, 59%). Metabolite analysis of BHD-associated kidney cancer revealed metabolic reprogramming toward upregulated redox regulation which may neutralize reactive oxygen species potentially produced from mitochondria with increased respiratory capacity under FLCN-deficiency. BHD-associated kidney cancer displays unique molecular characteristics that are completely different from sporadic kidney cancer, providing mechanistic insight into tumorigenesis under FLCN-deficiency as well as a foundation for development of novel therapeutics for kidney cancer.

Genetic disorders and male infertility.

BACKGROUND: At present, one out of six couples is infertile, and in 50% of cases, infertility is attributed to male infertility factors. Genetic abnormalities are found in 10%-20% of patients showing severe spermatogenesis disorders, including non-obstructive azoospermia. METHODS: Literatures covering the relationship between male infertility and genetic disorders or chromosomal abnormalities were studied and summarized. MAIN FINDINGS RESULTS: Genetic disorders, including Klinefelter syndrome, balanced reciprocal translocation, Robertsonian translocation, structural abnormalities in Y chromosome, XX male, azoospermic factor (AZF) deletions, and congenital bilateral absence of vas deferens were summarized and discussed from a practical point of view. Among them, understanding on AZF deletions significantly changed owing to advanced elucidation of their pathogenesis. Due to its technical progress, AZF deletion test can reveal their delicate variations and predict the condition of spermatogenesis. Thirty-nine candidate genes possibly responsible for azoospermia have been identified in the last 10 years owing to the advances in genome sequencing technologies. CONCLUSION: Genetic testing for chromosomes and AZF deletions should be examined in cases of severe oligozoospermia and azoospermia. Genetic counseling should be offered before and after genetic testing.

Early assessment with 18F-2-fluoro-2-deoxyglucose positron emission tomography/computed tomography to predict short-term outcome in clear cell renal carcinoma treated with nivolumab.

BACKGROUND: We reported previously the usefulness of 18F-2-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) to predict prognosis of renal cell carcinoma (RCC) treated with molecular targeted agents. Herein we describe a preliminary research of nine patients who underwent FDG-PET/CT before and after initiation of nivolumab. METHODS: Patients with metastatic RCC who were treated by nivolumab from October 2016 to March 2017 were enrolled in this study. All patients underwent FDG-PET/CT at baseline and 1 month as a first response assessment, and contrast-enhanced or non-contrast-enhanced CT scan at 4 month as a second response assessment. Logistic regression analysis was performed to assess the association of potential predictors, including age, gender, baseline diameter, baseline maximum standardized uptake value (SUVmax), lung or not lung metastasis, elevation of SUVmax at 1st assessment, and decrease in diameter at 1st assessment with the response at 2nd assessment (decrease in the diameter ≥ 30% or not). RESULTS: There were 9 patients and 30 lesions. Mean days of first assessment with FDG-PET/CT and second assessment by CT scan from initiation of treatment were 32.3 ± 6.4, 115.5 ± 14.9, respectively. Lesions whose diameter decreased ≥30% at second assessment were defined as responding, and lesions whose diameter did not decrease ≥30% were defined as non-responding. There were 18 responding lesions, and 12 non-responding lesions. We compared change in diameter and SUVmax at first assessment with FDG-PET/CT, respectively. All lesions with decreased diameter and elevated SUVmax at first assessment with FDG-PET/CT showed responding at second assessment by CT scan, while most lesions with increased diameter and declined SUVmax at first assessment showed non-responding at second assessment. The multivariate logistic regression analyses revealed that only the elevation of SUVmax at 1 month was an independent predictor (P = 0.025, OR: 13.087, 95%CI: 1.373-124.716). CONCLUSION: Our findings suggest that the early assessment using FDG-PET/CT can be effective to predict the response of RCC to nivolumab. However, larger prospective studies are needed to confirm these preliminary results. TRIAL REGISTRATION: Registered in University Hospital Medical Information Network in JAPAN [ UMIN0000008141 ], registration date: 11 Jun 2012.

Recognition and attitudes of Japanese hematologists on sperm banking before chemotherapy: present status from nationwide questionnaire survey.

BACKGROUND: Treatment advancements have improved young cancer patients' survival rate considerably. Fertility preservation has become a very important tool in the prevention of treatment-induced gonadal toxicity. This study aimed to examine hematologists' awareness of its necessity and importance. METHODS: Questionnaires were mailed to the directors of 230 institutes that treated hematological malignancies in adults. The directors were asked to provide information regarding their institutes, collaboration with sperm banks, the number of patients treated per year, selection criteria for patients providing information, and their awareness of and attitudes toward sperm preservation. RESULTS: The response rate was 40.0%. Municipal and private hospitals treated patients significantly less frequently relative to university hospitals (p = .002). Of the 92 participating hematology institutions, 17 included sperm banks and 69 collaborated with sperm banks in neighboring institutions. Many participants stated that sperm preservation should be performed before chemotherapy; however, only 38% provided sperm preservation information to all patients. Participants in facilities without sperm banks exhibited significantly lower levels of knowledge regarding sperm preservation, relative to those from institutions with sperm banks, and found discussing fertility preservation burdensome. This trend was identical to that observed in a survey conducted 10 years earlier. CONCLUSION: Many hematologists did not appear to possess sufficient knowledge regarding fertility preservation. Moreover, few institutions included sperm banks, and a considerable burden was exerted on hematologists. The introduction of support systems is required to promote sperm preservation before cancer treatment.

[A Case of Polyorchidism Associated with Infertility].

A 30-year-old man present with infertility for 2 years. Magnetic resonance imaging (MRI) revealed two right testes in the scrotum and inguinal region, respectively. Semen analysis revealed cryptozoospermia. Polyorchidism was considered to have caused spermatogenic dysfunction and male infertility. We performed right high orchiectomy and simultaneous testicular sperm extraction on the same testis. To our knowledge, this is the first case of testicular sperm extraction performed for patients with polyorchidism.

Gastrointestinal cancer and bilateral hydronephrosis resulted in a high risk of ureteral stent failure.

BACKGROUND: Urologists frequently encounter malignant ureteral obstruction (MUO) caused by advanced urological or non-urological malignant disease, but the treatment policy is unclear. The present study examined the risk factors for predicting ureteral stent failure in patients with MUO after ureteral stent insertion and the change in the renal function after retrograde ureteral stent insertion in cases of bilateral hydronephrosis. METHODS: A total of 39 patients who required ureteral stent placement for MUO at Yokohama City University Medical Center (Yokohama, Japan) between February 2007 and May 2016 were included in this study. The age, gender, type of cancer, hydronephrosis side, pre-stenting estimated glomerular filtration rate (eGFR), and eGFR increase were assessed as predictive factors for stent failure. Among these 39 patients, 25 showed bilateral hydronephrosis. Thirteen of these patients had bilateral ureteral stents placed, and the remaining 12 had a unilateral ureteral stent placed. The renal function and overall survival (OS) were analyzed between these two groups. RESULTS: Among all 39 patients, 9 (23.1%) had stent failure. A univariate analysis revealed that causative disease (gastrointestinal cancer vs. others; p = 0.045) and laterality of hydronephrosis (bilateral vs. unilateral; p = 0.05) were associated with stent failure. A multivariate analysis revealed that only age (hazard ratio, 0.938; 95% confidence interval, 0.883-0.996; p = 0.038) was associated with stent failure. A Kaplan-Meier analysis and log-rank test indicated that having a unilateral ureteral stent placed was not correlated with a lower OS rate than having bilateral ureteral stents placed (p = 0.563). Among patients with bilateral hydronephrosis, the increase in the eGFR of those who had bilateral ureteral stents placed was not significantly different from that of those who had a unilateral ureteral stent placed (p = 0.152). CONCLUSIONS: We revealed that age > 60 years was helpful for predicting stent failure. MUO due to gastrointestinal cancer and bilateral hydronephrosis may be predictive of stent failure. These factors may help urologists decide the optimal time to perform early percutaneous nephrostomy. These findings suggest that patients with bilateral hydronephrosis do not necessarily need to have a ureteral stent placed into both sides of the hydronephrosis.

PD-1 and PD-L1 are more highly expressed in high-grade bladder cancer than in low-grade cases: PD-L1 might function as a mediator of stage progression in bladder cancer.

BACKGROUND: Bladder cancers have been characterized as a tumor group in which the immunological response is relatively well preserved. Programmed death ligand 1 (PD-L1, B7-H1, CD274) has been shown to be expressed in several malignancies, including bladder cancer. However, the clinicopathological impact of this biomarker has not yet been established. In the present study, a quantitative real-time polymerase chain reaction (qPCR) was performed using paired normal and cancerous bladder cancer tissue to investigate PD-1/PD-L1 gene expression. METHODS: We examined the mRNA expression of PD-1/PD-L1 by a qPCR using 58 pairs of normal and cancerous human bladder tissue specimens. We also examined the correlation with the expressions of the STAT1 and NFAT genes, which are thought to be upstream and downstream of the PD-L1 pathway, respectively. RESULTS: There were no significant differences between normal and cancerous tissue in the expression of the PD-1 and PD-L1 genes (p = 0.724 and p = 0.102, respectively). However, PD-1 and PD-L1 were both more highly expressed in high-grade bladder cancer than in low-grade bladder cancer (p < 0.050 and p < 0.010). PD-L1 was positively correlated with the expressions of both the STAT1 (r = 0.681, p < 0.001) and the NFATc1 genes (r = 0.444. p < 0.001). CONCLUSIONS: PD-1 and PD-L1 might be a new biomarker that correlates with the pathological grade of bladder cancer. PD-L1 might function as a mediator of stage progression in bladder cancer and STAT1-NFAT pathway might associate this function.