Prognostic factors for sperm retrieval in non-obstructive azoospermia

Discordant Bilateral Testicular Pathology Does not Affect Sperm Retrieval Rate in Bilateral Microdissection Testicular Sperm Extraction (mTESE)

OBJECTIVE

To assess the incidence of discordant testicular pathology in men undergoing bilateral microdissection testicular sperm extraction (mTESE) and association with sperm retrieval rate.

METHODS

We performed a retrospective single-institutional review of all patients undergoing mTESE from 2007 to 2021 and aggregated clinical history, physical exam, semen analysis, and operative findings. Specimens with discordant pathology were re-reviewed by an experienced genitourinary.ßpathologist and categorized in a standardized fashion. Data were analyzed using SPSS.

RESULTS

One hundred fourteen non-obstructive azoospermia.ßmen undergoing 132 mTESEs were identified within the study period. Eighty-five percent (112/132) of cases had pathology specimens available, and within this specific cohort the success rate was 41.9% (47/112). A total of 206 pathological reports resulted including 52.4% Sertoli cell only, 4.9% Leydig cell hyperplasia, 8.7% fibrosis, 16.5% maturation arrest, and 17.5% hypospermatogenesis. Twelve percent of testicles had more than 1 pathologic diagnosis. Sixty-six men had synchronous bilateral testicular pathology, and 11/66 (16.6%) had at least partially discordant pathology on initial review. Focused re-review by a genitourinary pathologist confirmed exclusively discordant pathology in 7/66 (10.6%) cases, with a sperm retrieval rate of 57% (4/7). The sperm retrieval rate.ßin men with discordant pathology was not significantly different from those with concordant pathology.

CONCLUSION

Over 1 in 10 men undergoing mTESE may have discordant pathology between testicles, though this may not affect sperm retrieval rate.ßat the time of procedure. Clinicians should consider submitting bilateral testicular specimens for pathology to (1) clarify their outcomes data, and (2) assist with clinical decision-making and surgical planning if a repeat mTESE is indicated.

Potential of testis-derived circular RNAs in seminal plasma to predict the outcome of microdissection testicular sperm extraction in patients with idiopathic non-obstructive azoospermia

STUDY QUESTION

Do testis-derived circular RNAs (circRNAs) in seminal plasma have potential as biomarkers to predict the outcome of microdissection testicular sperm extraction (micro-TESE) in patients with idiopathic non-obstructive azoospermia (NOA)?

SUMMARY ANSWER

Testis-derived circRNAs in the seminal plasma can indeed be used for predicting the outcome of micro-TESE in patients with idiopathic NOA.

WHAT IS KNOWN ALREADY

Micro-TESE is an effective method to obtain sperm samples from patients with idiopathic NOA. However, its success rate is only 40-50% in such patients.

STUDY DESIGN, SIZE, DURATION

Six idiopathic NOA patients with different micro-TESE results were included as the discovery cohort. Their testicular tissues were used for extracting and sequencing circRNAs. Five circRNAs with the most significantly different expression levels were selected for further verification.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Fifty-two patients with idiopathic NOA were included as the validation cohort. Preoperative seminal plasma samples of 52 patients with idiopathic NOA and 25 intraoperative testicular tissues were collected and divided into 'success' and 'failure' groups according to the results of micro-TESE. Quantitative real-time polymerase chain reaction was performed to verify differences in the expression levels of the selected circRNAs between the two groups in the testicular tissues and seminal plasma.

MAIN RESULTS AND THE ROLE OF CHANCE

Whether at the seminal plasma or testicular tissue level, the differences in the expression levels of the three circRNAs (hsa_circ_0000277, hsa_circ_0060394 and hsa_circ_0007773) between the success and failure groups were consistent with the sequencing results. A diagnostic receiver operating curve (ROC) analysis of the AUC indicated excellent diagnostic performance of these circRNAs in seminal plasma in predicting the outcome of micro-TESE (AUC values: 0.920, 0.928 and 0.891, respectively). On the basis of least absolute shrinkage and selection operator (LASSO) logistic regression, the three circRNAs were combined to construct a new prediction model. The diagnostic ROC curve analysis of the model showed an AUC value of 0.958. The expression levels of these circRNAs in seminal plasma using three normospermic volunteer samples remained stable after 48 h at room temperature.

LARGE SCALE DATA

NA.

LIMITATIONS, REASONS FOR CAUTION

This was a single-center retrospective study with relatively few cases. The functions of these circRNAs, as well as their relationship with spermatogenesis, have not yet been established.

WIDER IMPLICATIONS OF THE FINDINGS

Testis-derived circRNAs in seminal plasma can reflect the microenvironment of the testis and can be used as reliable biomarkers to screen patients with idiopathic NOA who might be suitable for micro-TESE.

STUDY FUNDING/COMPETING INTEREST(S)

This article was funded by the National Natural Science Foundation of China (Grant no. 81871151). There were no competing interests.

"Second-look" Micro Testicular Sperm Extraction (MicroTESE) in Patients with Non-obstructive Azoospermia Following Histopathological Analysis

Introduction:

Microdissection testicular sperm extraction (microTESE) is considered the gold standard method for surgical sperm retrieval among patients with non-obstructive azoospermia (NOA).

Aim:

This study aimed to evaluate the correlation between histopathological findings after failed microTESE procedure and outcomes of the „second-look“ procedure and to provide insight into the most common histopathological patterns after testicular biopsy within our population.

Methods:

The retrospective study included 33 selected patients with NOA, who had undergone unsuccessful sperm retrieval. The diagnosis of NOA was made after the assessment of the patient’s history data, a physical examination, semen analysis, the hormonal profile, and genetic studies. After negative sperm retrieval, histopathological report has been analyzed for „second-look“ microTESE attempt.

Results:

Five testicular histopathological patterns were found: hypospermatogenesis (9,1%), Sertoli cell-only syndrome (43%), germ cell maturation arrest (15%), seminiferous tubule hyalinization (15%), mixed pattern (21%). Y-microdeletions were detected in 5 patients, of which 3 patients showed AZFc region deletions. Only 3 patients (9,1%) underwent a „second-look“ procedure after the evaluation of histopathological reports. After the stimulation therapy and „second-look“ procedure, we had a positive outcome in a single patient (33,3%). Mean FSH value in patients with confirmed spermatogenesis was 17.26±3.11IU/l, while mean FSH value in patients without presence or germ cell statistically significantly exceeded and was 24.28±4.71IU/L (p=0.038).

Conclusion:

Histopathological reports following the microTESE procedure are obligatory for the proper selection of patients who are candidates for the „second-look“ microTESE attempt. Patients with Sertoli cell-only syndrome and hypospermatogenesis particularly can benefit from the “second-look” procedure.

Factors Influencing the Decision for Fresh vs Cryopreserved Microdissection Testicular Sperm Extraction for Non-Obstructive Azoospermia

OBJECTIVE

To determine reproductive urologists' (RU) practice patterns for microdissection testicular sperm extraction (microTESE) and factors associated with use of fresh vs frozen microTESE for non-obstructive azoospermia.

MATERIALS AND METHODS

We electronically surveyed Society for Study of Male Reproduction members with a 21-item questionnaire. Our primary outcomes were to determine RU preference for fresh or frozen microTESE and to understand barriers to performing microTESE. Pearson's chi-square and Fisher's exact tests were used to analyze categorical outcomes and candidate predictor variables. Firth logistic regression was performed to identify the predictors for preferring and performing fresh vs frozen microTESE.

RESULTS

A total of 208 surveys were sent with 76 responses. Most (63.0%) primarily perform frozen microTESE for non-obstructive azoospermia, while 37.0% primarily perform fresh. However, in an ideal practice, 59.3% prefer fresh microTESE, 22.2% prefer frozen microTESE, and 18.5% had no preference. MicroTESE is performed most often (61.1%) at surgical centers not affiliated with a fertility practice. The most commonly reported barriers for both fresh and frozen microTESE are cost (42.6%), scheduling (33.3%), and andrologist unavailability (16.7%). There are no statistically significant differences between these barriers and performing fresh vs frozen microTESE. On multivariable analysis, reproductive endocrinology and infertility-based surgical center (OR 22.9; 95% CI 1.1-467.2; P = 0.04) and professional fee $2,500-$4,999 (OR 20.7; 95% CI 1.27-337.9; P = 0.03) are significant predictors of performing fresh microTESE.

CONCLUSION

Frozen microTESE is performed more commonly than fresh, despite most RU preferring fresh microTESE in an ideal setting. Both fresh and frozen microTESE have a role in reproductive care. Barriers to performing fresh microTESE include cost, scheduling and andrologist availability.

Altered Gene Expression in the Testis of Infertile Patients with Nonobstructive Azoospermia

Background

The molecular mechanism of nonobstructive azoospermia (NOA) remains unclear. The aim of this study was to identify gene expression changes in NOA patients and to explore potential biomarkers and therapeutic targets.

Methods

The gene expression profiles of GSE45885 and GSE145467 were collected from the Gene Expression Omnibus (GEO) database, and the differences between NOA and normal spermatogenesis were analyzed. Enrichment analysis was performed to explore biological functions for common differentially expressed genes (DEGs) in GSE45885 and GSE145467. Coexpression analysis of DEGs in GSE45885 was performed, and two modules with the highest correlation with NOA were screened. Key genes were then screened from the intersection genes of the two modules and common DEGs and PPI network. The expression of key genes was validated by quantitative real-time polymerase chain reaction (qRT-PCR) experiments. Finally, through miRTarBase, miRDB, and RAID, the miRNAs were predicted to regulate key genes, respectively.

Results

A total of 345 common DEGs were identified and they were mainly related to spermatogenesis, insulin signaling pathway. Coexpression analysis of DEGs in GSE45885 yielded eight modules; MEblack and MEturquoise had the highest correlation with NOA. Six genes in MEturquoise and RNF141 in MEblack were identified as key genes. qRT-PCR experiments validated the differential expression of key genes between NOA and control. Furthermore, RNF141 was regulated by the largest number of miRNAs.

Conclusion

Our findings suggest that the significant change expression of key genes may be potential markers and therapeutic targets of NOA and may have some impact on the development of NOA.

Two Decades from the Introduction of Microdissection Testicular Sperm Extraction: How This Surgical Technique Has Improved the Management of NOA

The treatment of men with non-obstructive azoospermia (NOA) has improved greatly over the past two decades. This is in part due to the discovery of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), but also significantly due to improvements in surgical sperm retrieval methods, namely the development of microdissection testicular sperm extraction (mTESE). This procedure has revolutionized the field by allowing for identification of favorable seminiferous tubules while simultaneously limiting the amount of testicular tissue removed. Improving sperm retrieval rates is imperative in this cohort of infertile men as there are a limited number of factors that are predictive of successful sperm retrieval. Currently, sperm retrieval in NOA men remains dependent on surgeon experience, preoperative patient optimization and teamwork with laboratory personnel. In this review, we discuss the evolution of surgical sperm retrieval methods, review predictors of sperm retrieval success, compare and contrast the data of conventional versus mTESE, share tips for optimizing sperm retrieval outcomes, and discuss the future of sperm retrieval in men with NOA.

Methylation patterns of methylenetetrahydrofolate reductase gene promoter in infertile males

Errors of folate/homocysteine pathways which are critical for transferring methyl groups have been suggested to affect male fertility. We aimed to evaluate the methylation patterns of the promoter of methylenetetrahydrofolate reductase (MTHFR) gene in infertile males and to investigate the association between MTHFR promoter methylation and success of sperm retrieval. Thirty-five nonobstructive azoospermic and 46 severe oligozoospermic patients constituted the study group and were compared with 49 fertile and/or normozoospermic men. The methylation status was analysed by methylation-specific polymerase chain reaction. MTHFR promoter methylation was detected in infertile men with NOA and SO in the ratio of 48.6% and 58.7%, respectively. Methylation was also observed in 51% of controls. MTHFR promoter was methylated in 65% of men with viable spermatozoon during TESE. No association was found regarding to the profile of MTHFR promoter methylation between both NOA and SO patients and controls (p = .621). There was no relation between the methylation status of MTHFR promoter and low motility and poor morphology (p = .682 and p = .413, respectively). No association was found between MTHFR promoter methylation and presence of viable spermatozoa (p = .382). Our data indicate that the promoter methylation of MTHFR gene may not be associated with male infertility.

Testicular volume in non-obstructive azoospermia with a history of bilateral cryptorchidism may predict successful sperm retrieval by testicular sperm extraction

Purpose

Cryptorchidism is one of the most common causes of non‐obstructive azoospermia (NOA) in adulthood. Even if early orchidopexy is performed to preserve fertility potential, some patients still suffer from azoospermia. Fertility potential is significantly lower in bilateral than unilateral cryptorchidism. The aims of this study were to identify clinical parameters that predict the likely success of sperm recovery by microscopic testicular sperm extraction (micro‐TESE) and also the likely outcome of intracytoplasmic sperm injection using sperm from NOA patients who submitted to bilateral orchidopexy.

Methods

Fifty‐two NOA patients with a history of bilateral cryptorchidism underwent micro‐TESE. The following clinical parameters were evaluated as predictive factors for successful sperm recovery: age at micro‐TESE; age at orchidopexy; period from orchidopexy to micro‐TESE; luteinizing hormone (LH); follicle‐stimulating hormone (FSH); testosterone; average testicular volume; and body mass index.

Results

In the successful sperm retrieval group, average testicular volume was significantly greater, while serum LH and FSH, and body mass index were significantly lower. In a multivariate analysis, average testicular volume was positively correlated with successful sperm recovery.

Conclusion

Our results indicate that testicular volume in NOA patients with bilateral cryptorchidism is a predictor for successful sperm recovery.

Predictors of surgical sperm retrieval in non-obstructive azoospermia: summary of current literature

Intracytoplasmic sperm injection (ICSI), combined with surgical sperm retrieval (SR) techniques, is the sole option for patients with non-obstructive azoospermia to achieve fertility; however, with suboptimal results. Given the variability in clinical presentation, the potential role of factors that can predict the likelihood of successful testicular SR needs to be clarified. This article summarizes the current evidence concerning the variables predicting SR success in non-obstructive azoospermic patients with spermatogenic failure. For this, we used 60 articles, including 46 original papers and six meta-analyses. Clinical and laboratory factors, as well as adjuvant therapies and surgical retrieval methods, were the factors most commonly investigated. We found that Klinefelter syndrome, Y chromosome microdeletions in regions AZFa/b, and Sertoli cell-only histopathology were associated with reduced SR success. By contrast, testis volume > 12.5 ml, history of cryptorchidism, use of micro-TESE as the sperm retrieval method, and adjuvant therapy were associated with improved SR success. None of the predictors, alone or combined, provide definitive information about the chances of harvesting sperm in men with non-obstructive azoospermia, except for Y chromosome microdeletions in regions AZFa/b. In the latter, SR success is virtually nil. We conclude that SR outcomes in men with non-obstructive azoospermia are difficult to predict based on the existing variables. Although several predictors can be used for patient counseling, their clinical value is limited to either ensure SR success or discourage reproductive urologists from recommending SR to men with non-obstructive azoospermia seeking fertility. A notable exception includes the deletions involving the regions AZFa and/or AZFb of the Y chromosome; the affected patients should be counseled against undergoing SR.

Open testicular mapping: A less invasive multiple biopsy approach for testicular sperm extraction

This study proposes a testicular sperm extraction technique that was inspired by testicular fine-needle aspiration. Here, we have described the technique of open testicular mapping (OTEM) and evaluated the successful sperm recovery in 92 patients with nonobstructive azoospermia (NOA). All patients underwent an OTEM biopsy. Patients were divided into two groups; group I included men with spermatozoa recovered and group 0 included men without spermatozoa recovered. Age, follicle-stimulating hormone (FSH) level and testicular volume were compared between the groups. In 50 of 92 men (54%), viable spermatozoa were found after OTEM. No differences were noted in age, FSH level or testicular volume. Using OTEM, it was possible to retrieve spermatozoa in 54% of the NOA men.

Isoform-Level Gene Expression Profiles of Human Y Chromosome Azoospermia Factor Genes and Their X Chromosome Paralogs in the Testicular Tissue of Non-Obstructive Azoospermia Patients

The human Y chromosome has an inevitable role in male fertility because it contains many genes critical for spermatogenesis and the development of the male gonads. Any genetic variation or epigenetic modification affecting the expression pattern of Y chromosome genes may thus lead to male infertility. In this study, we performed isoform-level gene expression profiling of Y chromosome genes within the azoospermia factor (AZF) regions, their X chromosome counterparts, and few autosomal paralogues in testicular biopsies of 12 men with preserved spermatogenesis and 68 men with nonobstructive azoospermia (NOA) (40 Sertoli-cell-only syndrome (SCOS) and 28 premiotic maturation arrest (MA)). This was undertaken using quantitative real-time PCR (qPCR) at the transcript level and Western blotting (WB) and immunohistochemistry (IHC) at the protein level. We profiled the expression of 41 alternative transcripts encoded by 14 AZFa, AZFb, and AZFc region genes (USP9Y, DDX3Y, XKRY, HSFY1, CYORF15A, CYORF15B, KDM5D, EIF1AY, RPS4Y2, RBMY1A1, PRY, BPY2, DAZ1, and CDY1) as well as their X chromosome homologue transcripts and a few autosomal homologues. Of the 41 transcripts, 18 were significantly down-regulated in men with NOA when compared with those of men with complete spermatogenesis. In contrast, the expression of five transcripts increased significantly in NOA patients. Furthermore, to confirm the qPCR results at the protein level, we performed immunoblotting and IHC experiments (based on 24 commercial and homemade antibodies) that detected 10 AZF-encoded proteins. In addition, their localization in testis cell types and organelles was determined. Interestingly, the two missing proteins, XKRY and CYORF15A, were detected for the first time. Finally, we focused on the expression patterns of the significantly altered genes in 12 MA patients with successful sperm retrieval compared to those of 12 MA patients with failed sperm retrieval to predict the success of sperm retrieval in azoospermic men. We showed that HSFY1-1, HSFY1-3, BPY2-1, KDM5C2, RBMX2, and DAZL1 transcripts could be used as potential molecular markers to predict the presence of spermatozoa in MA patients. In this study, we have identified isoform level signature that can be used to discriminate effectively between MA, SCOS, and normal testicular tissues and suggests the possibility of diagnosing the presence of mature sperm cell in azoospermic men to prevent additional testicular sperm extraction (TESE) surgery.

Genetic study of Hormad1 and Hormad2 with non-obstructive azoospermia patients in the male Chinese population

PURPOSE

To evaluate the association of the Hormad1 and Hormad2 single nucleotide polymorphisms (SNPs) variants with non-obstructive azoospermia (NOA) in the Chinese population.

METHODS

In the present study, we assessed 10 single nucleotide polymorphisms (SNPs) of Hormad1 and Hormad2 using Sequenom iplex technology in 361 NOA cases and 368 normal controls from Chinese population.

RESULTS

We observed no statistical differences in the distribution of allele frequencies. Further genetic model analysis and haplotype analysis also showed no significant difference between the two groups. However, we found that genotype distribution of rs718772 of Hormad2 was significantly different between the larger testis group (average testis volume ≥10 ml) and the small testis group (average testis volume <10 ml) in the NOA patients (P = 0.035).

CONCLUSIONS

In conclusion, Hormad1 and Hormad2 might not be the susceptible genes for the non-obstructive azoospermia in our study population. However, rs718772 of Hormad2 variant might be associated with testis development in NOA patients.

The azoospermic male: current knowledge and future perspectives

This special issue is fully dedicated to the topic of azoospermia and contains the seminal work of renowned scientists and clinicians from seven countries on three continents. In seventeen chapters, a comprehensive review of the epidemiology, genetics, physiopathology, diagnosis, and management of azoospermia addresses our current knowledge on the topic. The clinical results of assisted reproductive techniques applied to this category of male infertility and the health of offspring originating from such fathers are critically analyzed. In addition, the challenges and the future biotechnological perspectives for the treatment of azoospermic males seeking fertility are discussed.