Quantitative Histology of Germ Cells in the Undescended Testes of Human Fetuses, Neonates and Infants

Anogenital distance in a cohort of 169 infant boys with uni- or bilateral cryptorchidism including 18 boys with vanishing testes

STUDY QUESTION

Do different boys with different types of cryptorchidism exhibit different anogenital distances (AGDs)?

SUMMARY ANSWER

Length of AGD seemed to differ in different groups of patients with cryptorchidism.

WHAT IS KNOWN ALREADY

AGD, which is used as an indicator of prenatal androgen action, tends to be shorter in boys with cryptorchidism compared to unaffected boys. Shorter AGDs have also been reported in boys with hypospadias, in men with poor semen quality, and in men with testicular cancer.

STUDY DESIGN, SIZE, DURATION

A prospective descriptive cohort study was performed using data from consecutively selected boys with cryptorchidism (n = 169) operated in a single center over a period of 3 years (September 2019 to October 2022).

PARTICIPANTS/MATERIALS, SETTING, METHODS

AGD was measured in 169 infant boys, at 3 to 26 months of age, during anesthesia with a vernier caliper measuring the distance from the anus to the base of the scrotum (AGDAS) and from the anus to the anterior base of the penis (AGDAP) in two body positions according to the methods by 'The Infant Development and the Environment Study' (TIDES) and 'Cambridge Baby Growth Study', resulting in four mean values per patient (TIDES AGDAS/AP and Cambridge AGDAS/AP). Normal values for AGD by age were set by our hospital Department of Growth and Reproduction based on a large cohort of healthy infant boys (n = 1940). Testicular biopsies were performed at orchidopexy as a clinical routine. The germ cell number (G/T) and type Ad spermatogonia number (AdS/T) per cross-sectional tubule of at least 100 and 250 tubules, respectively were measured and related to normal samples. Blood samples were obtained by venipuncture for measuring serum LH, FSH, and inhibin B. They were analyzed in our hospital Department of Growth and Reproduction where the normal reference was also established. Correlations between the four mean AGD measurements for each boy were evaluated by Spearman rank correlation analyses. The AGD measurement of every boy was transferred to the multiple of the median (MoM) of the normal AGD for age and named MoM AGD.

MAIN RESULTS AND THE ROLE OF CHANCE

There were 104 boysoperated for unilateral, and 47 boys operated for bilateral, undescended testes, whereas 18 boys had vanished testis including one boy with bilateral vanished testes. Only 6% of cases with vanished testes had a MoM AGD higher than the normal median compared to 32% with undescended testes (P < 0.05). MoM AGD increased with the age at surgery for boys with vanished testis (Spearman r = 0.44), but not for boys with undescended testes (Spearman r = 0.14). Boys with bilateral cryptorchidism had longer AGDs and more often had hypogonadotropic hypogonadism than boys with unilateral cryptorchidism (P < 0.005) and (P < 0.000001).

LIMITATIONS, REASONS FOR CAUTION

Although being the largest published material of AGD measurements of infant boys with cryptorchidism, one limitation of this study covers the quite small number of patients in the different groups, which may decrease the statistical power. Another limitation involves the sparse normal reference material on G/T and AdS/T. Finally, there are currently no longitudinal studies evaluating AGD from birth to adulthood and evaluating childhood AGD in relation to fertility outcome. Our study is hypothesis generating and therefore the interpretation of the results should be regarded as exploratory rather than reaching definite conclusions.

WIDER IMPLICATIONS OF THE FINDINGS

The study findings are in agreement with literature as the total included group of boys with cryptorchidism exhibited shorter than normal AGDs. However, new insights were demonstrated. Boys with vanished testis had shorter AGDs compared to unaffected boys and to boys with undescended testes. This finding challenges the current concept of AGD being determined in 'the masculinization programming window' in Week 8 to 14 of gestation. Furthermore, boys with bilateral cryptorchidism had longer AGDs and more often had hypogonadotropic hypogonadism than boys with unilateral cryptorchidism, suggesting that the lack of fetal androgen in hypogonadotropic hypogonadism is not that significant.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used and no competing interests are declared.

TRIAL REGISTRATION NUMBER

The trial was not registered in an ICMJE-recognized trial registry.

Cryptorchidism and puberty

Cryptorchidism is the condition in which one or both testes have not descended adequately into the scrotum. The congenital form of cryptorchidism is one of the most prevalent urogenital anomalies in male newborns. In the acquired form of cryptorchidism, the testis that was previously descended normally is no longer located in the scrotum. Cryptorchidism is associated with an increased risk of infertility and testicular germ cell tumors. However, data on pubertal progression are less well-established because of the limited number of studies. Here, we aim to review the currently available data on pubertal development in boys with a history of non-syndromic cryptorchidism-both congenital and acquired cryptorchidism. The review is focused on the timing of puberty, physical changes, testicular growth, and endocrine development during puberty. The available evidence demonstrated that the timing of the onset of puberty in boys with a history of congenital cryptorchidism does not differ from that of non-cryptorchid boys. Hypothalamic-pituitary-gonadal hormone measurements showed an impaired function or fewer Sertoli cells and/or germ cells among boys with a history of cryptorchidism, particularly with a history of bilateral cryptorchidism treated with orchiopexy. Leydig cell function is generally not affected in boys with a history of cryptorchidism. Data on pubertal development among boys with acquired cryptorchidism are lacking; therefore, more research is needed to investigate pubertal progression among such boys.

The fate of germ cells in cryptorchid testis

Cryptorchidism in males constitutes a notable risk factor for both infertility and testicular cancer. Infertility in adulthood is closely linked to the germ cell status in childhood. Furthermore, the significance of germ cell status is important as more than 95% of all reported testicular malignancies are germ cell tumors. The review aims to elucidate the pathogenesis of germ cells in cryptorchid testes concerning their association with infertility and testicular malignancies. Impaired germ cell numbers are evident in cryptorchid testes even during antenatal and neonatal stages. In cryptorchidism there is a rapid decline in germ cell number within the first year of life, partially attributed to physiologic gonocyte apoptosis. Additionally, germ cells fail to differentiate normally during mini-puberty leading to reduced germ cell proliferation and delayed clearance of gonocytes from the seminiferous epithelium. Absence of germ cells in testicular biopsies occurs already 10 months of age and germ cell deterioration progressively worsens with approximately 50% of persisting cryptorchid testes lacking germ cells during puberty. The deficient germ cell maturation and proliferation leads to later infertility. Elevated temperature in the cryptorchid testes and also hormonal deficiency contribute to this phenomenon. Germ cell neoplasia in situ (GCNIS) originating during fetal development may manifest in rare cases associated with disorders of sexual development, chromosomal abnormalities in boys, specific syndromes, and teratomas that include cryptorchidism. In adults, the presence of GCNIS predominantly represents a new histology pattern before invasive germ cell cancer is demonstrated and is neither congenital nor related to abnormal gonocyte transformation.

The positive predictive value of using fsh and Inhibin-B serum levels to diagnose gonadotropin insufficiency in bilateral cryptorchid boys is high

AIM OF STUDY

Despite early surgery, many boys with bilateral cryptorchidism at surgery have a reduced number of germ cells per tubular cross-section (G/T) in testicular biopsies and/or low inhibin-B with no elevated follicle-stimulating hormone (FSH) as expected based on a normal gonadotropin feed-back mechanism. Such boys have a high risk of later infertility because of insufficient gonadotropin stimulation and may benefit from adjuvant hormonal treatment. Testicular biopsies are not always wanted or accepted. The study aim was to investigate the value of a low inhibin-B and normal FSH to identify patients that might benefit from adjuvant hormonal treatment avoiding the need for testicular biopsy.

METHODS

A series of boys with cryptorchidism were evaluated with serum levels of inhibin-B and FSH in relation to G/T in testicular biopsies, which were compared to previously published age-matched normal control values.

RESULTS

A total of 365 boys who underwent bilateral orchidopexy between 0.4 and 7.8 (median: 2) years of age were included. Twenty-seven (7%) patients had increased FSH and low G/T, whereas 11 of these also had low inhibin-B indicating hypergonadotropic hypogonadism. Moreover, 85 (23%) patients between 0.75 and 7.5 (median: 2) years of age had both low G/T (median: 0.3) and low inhibin-B (median: 56 pg/ml) but normal FSH (median: 0.6 U/l) indicating a gonadotropin insufficiency. Three patients with normal FSH and low inhibin B had normal G/T.

DISCUSSION

Our study shows that if surgeons prefer to avoid testicular biopsies and only wish to rely on hormonal parameters (low inhibin-B and normal FSH) in order to diagnose a gonadotropin insufficiency as the cause of hypogonadism, they will identify only about 30% of such cases and overlook about 70% of patients sharing the same endocrinopathy. In addition, if surgeons treat patients for gonadotropin insufficiency only based on low inhibin-B and normal FSH they will solely treat patients with gonadotropin insufficiency and would not overtreat patients.

CONCLUSION

Adjuvant hormonal treatment was indicated by a gonadotropin insufficiency discerned in 23% of boys with bilateral cryptorchidism. Without histology, the clinicians are left with more difficult clinical judgments to identify patients for adjuvant hormonal treatment. The positive predictive value of low inhibin-B and normal FSH corroborated by low G/T was 0.97 (85/85 + 3), but the sensitivity was low (0.30).

Timely orchiopexy by 18 months of age: Are we meeting the standards defined by the 2014 AUA guidelines?

BACKGROUND

Cryptorchidism is one of the most common reasons for pediatric urology referral and one of the few pediatric urologic conditions in which there are established AUA guidelines that recommend orchiopexy be performed before 18 months of age. While access to timely orchiopexy has been studied previously, there is no current study with data from a national clinical database evaluating timely orchiopexy after the AUA guidelines were published. Additionally, prior studies on delayed orchiopexy may have included patients with an ascended testis, which is a distinct population from those with true undescended testicles.

OBJECTIVES

To evaluate in a national, clinical database if timely orchiopexy improved after the AUA guidelines were published in 2014. In particular, we aim to evaluate a younger group of patients, 0-5 years of age, in an effort to account for potential ascending testes.

STUDY DESIGN

Using Cerner Real-World Data™, a national, de-identified database of 153 million individuals, we analyzed pediatric patients undergoing orchiopexy in the United States from 2000 to 2021. We included males 0-18 years old and further focused on the subset 0-5 years. Primary outcome was timely orchiopexy, defined as age at orchiopexy less than 18 months. Predictor variables included race, ethnicity and insurance status. Statistical analyses were performed using logistic regression.

RESULTS

Of the total 17,012 individuals identified as undergoing orchiopexy, 9274 were ages 0-5 at the time of surgery. Comparing time periods pre and post AUA guidelines (2000-2014 versus 2015-2021), we found a significant difference in the proportion of timely orchiopexy (51% versus 56%, respectively; p < 0.0001) (Figure). In multivariable analyses, Hispanic (OR = 0.65, p < 0.0001), African American (OR = 0.74, p < 0.0001), and Native American males (OR = 0.66, p = 0.008) were less likely to have timely orchiopexy compared to non-Hispanic White males. Individuals without insurance (OR = 0.81, p = 0.03) or with public insurance (OR = 0.88, p = 0.02) were less likely to have timely orchiopexy as compared to those with private insurance.

CONCLUSIONS

Nearly a decade after publication of the AUA cryptorchidism guidelines, a large proportion of patients are still not undergoing orchiopexy by 18 months of age. This is the first study to show that timely orchiopexy has improved among patients 0-5 years, but the majority of patients are still not undergoing timely orchiopexy. Health disparities were apparent among Hispanic, African American, Native American, and uninsured males, highlighting the need for further progress in access to pediatric surgical care.

The Majority of Boys Having Orchidopexy for Congenital Nonsyndromic Cryptorchidism during Minipuberty Exhibited Normal Reproductive Hormonal Profiles

INTRODUCTION

 The activation of the hypothalamic-pituitary-gonadal axis that occurs in male minipuberty during the first 5 months of life is important for early germ cell development. Orchidopexy during minipuberty may improve fertility potential as the germinative epithelium may benefit from the naturally occurring gonadotropin stimulation. We hypothesize that most boys with congenital nonsyndromic cryptorchidism display normal reproductive hormonal profiles and histological findings during minipuberty.

METHODS

 We included boys with congenital nonsyndromic cryptorchidism who underwent orchidopexy at less than 160 days of age, having no potential for spontaneous resolution clinically. At surgery, testicular biopsies and reproductive hormones were collected and compared with normal reference values. We measured the germ cells (G/T) and type A dark spermatogonia number per tubule.

RESULTS

 Thirty-five boys aged 37 to 159 (median age: 124) days at orchidopexy were included, five were bilateral. G/T was below the normal lower range in 26% (9/35) of the cases. In six of these cases, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were above 97.5 percentile, whereas one case had FSH below 2.5 percentile. Totally, 97% (33/34, one FSH was missing) exhibited a normal LH/FSH ratio. LH was more often above 97.5 percentile than FSH: 34% (12/35) versus 3% (1/34, p < 0.001). Inhibin B was below 2.5 percentile in 17% (6/35) of cases who all proved FSH above normal mean and four had LH above normal mean.

CONCLUSION

 Generally, reproductive hormonal profiles of the cryptorchid boys exhibited normal minipubertal pattern. Thus, 26% of the boys had reduced germ cell number, and transient hypogonadotropic hypogonadism could be suspected in few cases.

Testicular Tissue Banking for Fertility Preservation in Young Boys: Which Patients Should Be Included?

Due to the growing number of young patients at risk of germ cell loss, there is a need to preserve spermatogonial stem cells for patients who are not able to bank spermatozoa. Worldwide, more and more clinics are implementing testicular tissue (TT) banking programs, making it a novel, yet indispensable, discipline in the field of fertility preservation. Previously, TT cryopreservation was predominantly offered to young cancer patients before starting gonadotoxic chemo- or radiotherapy. Nowadays, most centers also bank TT from patients with non-malignant conditions who need gonadotoxic conditioning therapy prior to hematopoietic stem cell (HSCT) or bone marrow transplantation (BMT). Additionally, some centers include patients who suffer from genetic or developmental disorders associated with prepubertal germ cell loss or patients who already had a previous round of chemo- or radiotherapy. It is important to note that the surgical removal of TT is an invasive procedure. Moreover, TT cryopreservation is still considered experimental as restoration methods are not yet clinically available. For this reason, TT banking should preferably only be offered to patients who are at significant risk of becoming infertile. In our view, TT cryopreservation is recommended for young cancer patients in need of high-risk chemo- and/or radiotherapy, regardless of previous low-risk treatment. Likewise, TT banking is advised for patients with non-malignant disorders such as sickle cell disease, beta-thalassemia, and bone marrow failure, who need high-risk conditioning therapy before HSCT/BMT. TT retrieval during orchidopexy is also proposed for patients with bilateral cryptorchidism. Since patients with a medium- to low-risk treatment generally maintain their fertility, TT banking is not advised for this group. Also for Klinefelter patients, TT banking is not recommended as it does not give better outcomes than a testicular sperm extraction later in life.

During infancy low levels of follicle-stimulating hormone may result in high rate of germ cell apoptosis

PURPOSE

It has been suggested that follicle-stimulating hormone (FSH) plays a role in preventing germ cell apoptosis. We aimed to compare apoptotic rate of boys with cryptorchidism having different levels of FSH in order to investigate its role in apoptosis.

METHODS

Hormonal profiles and testicular biopsies from 30 boys with unilateral cryptorchidism (age range: 4-14 months) were included. Based on FSH level, the boys were grouped into three (3 × 10) having high (>97.5percentile), low (<2.5percentile), or within normal range. Sections underwent immunohistochemical staining to analyze the number of germ cells and type A dark spermatogonia per cross-sectional tubule. One section was co-stained with immunofluorescent antibodies against an apoptotic marker (cleaved caspase-3), proliferation marker (Ki67), Sertoli cell marker (anti-Müllerian hormone) and processed by confocal imaging for analysis. Germ cell apoptosis was calculated as the apoptosis index (percentage caspase-3+ germ cells/total germ cell number).

RESULTS

Fifty percent (5/10) of the boys with low FSH had an apoptosis index above 90% compared with 15% (3/20) of the boys with normal or high FSH (p = 0.04). Caspase-3+ germ cells were most likely to be located on the basement membrane (p<0.05).

CONCLUSION

Our findings lead to trends proposing that FSH may play a role in preventing apoptosis.

TYPE OF STUDY

Prognosis Study LEVEL OF EVIDENCE: III.

A narrative review of the history and evidence-base for the timing of orchidopexy for cryptorchidism

INTRODUCTION

Consensus recommendations for surgical management of cryptorchidism recommend orchidopexy between 6 and 18 months of age. The COVID-19 pandemic has impacted elective surgical scheduling.

OBJECTIVE

In response to the COVID-19 pandemic, we sought to review the available data regarding the natural history, surgical management, and infertility- and cancer-related risks associated with cryptorchid testes. The purpose of this review is to provide parents, referring providers, and surgeons with information to inform their decisions to proceed with or delay orchidopexy.

METHODS

A retrospective review and analysis of all available articles relevant to the natural history, surgical management, and infertility- and cancer-related risks of cryptorchidism present on PubMed, SCOPUS, and Cochrane Library was conducted.

RESULTS

The quality of historic literature pertaining to the effect of cryptorchidism on fertility and malignancy differ, with poorer data available on fertility. Cryptorchid testes may show histologic differences as early as birth, and some of these changes may have prognostic value in future fertility. Formerly unilateral cryptorchid men have slightly but not significantly reduced paternity rates compared to the general population. Cryptorchid testes have an increased risk of germ cell carcinogenesis, and robust data suggest the risk for malignancy in cryptorchid testes increases substantially after puberty.

CONCLUSION

The current body of evidence regarding the risks for future infertility and testicular cancer support the consensus recommendations for surgical correction of cryptorchidism between 6 and 18 months of age. During the uncertain time of the COVID-19 pandemic, decision for orchidopexy is a shared-decision between physician and parent. For an infant or young boy with a unilateral undescended testes, delaying orchidopexy several months until a time of decreased exposure risk is unlikely to result in substantial or sustained fertility or malignant risks.

The impact of early and successful orchidopexy on hormonal follow-up for 208 boys with bilateral non-syndromic cryptorchidism

PURPOSE

Inhibin-B is produced by Sertoli cells and decreased values might be associated with impaired fertility potential. The aim of the study was to evaluate the impact of bilateral orchidopexy on serum inhibin-B and follicle-stimulating hormone (FSH).

METHODS

A cohort study including 208 bilateral cryptorchid boys (median age: 1.7 year) was evaluated with serum inhibin-B and FSH in relation to histological parameters. Based on the fertility potential, the boys were divided into three subgroups. At follow-up (median age: 2.7 years) the boys were evaluated with FSH and in case of inhibin-B using multiple of the median (MoM).

RESULTS

Inhibin-B MoM improved significantly at follow-up. In 32 boys with high FSH at orchidopexy 63% normalized FSH and 59% increased MoM inhibin-B, but 31% had impaired inhibin-B at follow-up. In 105 boys with transient hypogonadotropic hypogonadism, 52% increased inhibin-B MoM but 31% had impaired inhibin-B at follow-up. In 71 boys with normal FSH, inhibin-B, and G/T, 54% increased inhibin-B MoM and 15% had impaired inhibin-B at follow-up. The effect of the surgery was best in patients younger than 1 year.

CONCLUSION

Orchidopexy, especially before 1 year of age, improves the fertility potential in bilateral cryptorchidism. At follow-up, 26% (54/208) had a risk of infertility based on inhibin-B.

Review of injection techniques for spermatogonial stem cell transplantation

BACKGROUND

Although the prognosis of childhood cancer survivors has increased dramatically during recent years, chemotherapy and radiation treatments for cancer and other conditions may lead to permanent infertility in prepubertal boys. Recent developments have shown that spermatogonial stem cell (SSC) transplantation may be a hope for restoring fertility in adult survivors of childhood cancers. For this reason, several centres around the world are collecting and cryopreserving testicular tissue or cells anticipating that, in the near future, some patients will return for SSC transplantation. This review summarizes the current knowledge and utility of SSC transplantation techniques.

OBJECTIVE AND RATIONALE

The aim of this narrative review is to provide an overview of the currently used experimental injection techniques for SSC transplantation in animal and human testes. This is crucial in understanding and determining the role of the different techniques necessary for successful transplantation.

SEARCH METHODS

A comprehensive review of peer-reviewed publications on this topic was performed using the PubMed and Google Scholar databases. The search was limited to English language work and studies between 1994 (from the first study on SSC transplantation) and April 2019. Key search terms included mouse, rat, boar, ram, dog, sheep, goat, cattle, monkey, human, cadaver, testes, SSC transplantation, injection and technique.

OUTCOMES

This review provides an extensive clinical overview of the current research in the field of human SSC transplantation. Rete testis injection with ultrasonography guidance currently seems the most promising injection technique thus far; however, the ability to draw clear conclusions is limited due to long ischemia time of cadaver testis, the relatively decreased volume of the testis, the diminishing size of seminiferous tubules, a lack of intratesticular pressure and leakage into the interstitium during the injection on human cadaver testis. Current evidence does not support improved outcomes from multiple infusions through the rete testes. Overall, further optimization is required to increase the efficiency and safety of the infusion method.

WIDER IMPLICATIONS

Identifying a favourable injection method for SSC transplantation will provide insight into the mechanisms of successful assisted human reproduction. Future research could focus on reducing leakage and establishing the optimal infusion cell concentrations and pressure.

Comparison of diagnostic and treatment guidelines for undescended testis

Cryptorchidism or undescended testis is the single most common genitourinary disease in male neonates. In most cases, the testes will descend spontaneously by 3 months of age. If the testes do not descend by 6 months of age, the probability of spontaneous descent thereafter is low. About 1%-2% of boys older than 6 months have undescended testes after their early postnatal descent. In some cases, a testis vanishes in the abdomen or reascends after birth which was present in the scrotum at birth. An inguinal undescended testis is sometimes mistaken for an inguinal hernia. A surgical specialist referral is recommended if descent does not occur by 6 months, undescended testis is newly diagnosed after 6 months of age, or testicular torsion is suspected. International guidelines do not recommend ultrasonography or other diagnostic imaging because they cannot add diagnostic accuracy or change treatment. Routine hormonal therapy is not recommended for undescended testis due to a lack of evidence. Orchiopexy is recommended between 6 and 18 months at the latest to protect the fertility potential and decrease the risk of malignant changes. Patients with unilateral undescended testis have an infertility rate of up to 10%. This rate is even higher in patients with bilateral undescended testes, with intra-abdominal undescended testis, or who underwent delayed orchiopexy. Patients with undescended testis have a threefold increased risk of testicular cancer later in life compared to the general population. Self-examination after puberty is recommended to facilitate early cancer detection. A timely referral to a surgical specialist and timely surgical correction are the most important factors for decreasing infertility and testicular cancer rates.

The role of gonadotrophins in gonocyte transformation during minipuberty

PURPOSE

Postnatal surge of gonadotrophins, Luteinizing hormone (LH) and Follicle-Stimulating hormone (FSH) known as minipuberty, is critical for gonocyte maturation into spermatogonial stem cells (SSC) in the testis. Gonadotrophins are essential for optimum fertility in men, but very little is known how they regulate germ cells during minipuberty. This study examined whether gonadotrophins play a role on gonocyte transformation in vivo.

METHODS

Testes from hypogonadal (hpg) mice and their wild type (WT) littermates (n = 6/group) were weighed, and processed in paraffin at postnatal days (D) 0, 3, 6 and 9. Mouse VASA homologue (germ cell marker), anti-Müllerian hormone (Sertoli cell marker) antibodies and DAPI (nuclei marker) were used for immunofluorescence followed by confocal imaging. Germ cells on or off basement membrane (BM) and Sertoli cells/tubule were counted using Image J and analyzed with GraphPad.

RESULTS

Comparing to WT littermates, there were significantly fewer germ cells on BM/tubule (p < 0.05) in D9 hpg mice, whereas there was no significant difference for germ cells off BM/tubule and Sertoli cells/tubule between littermates. However, testicular weight was significantly reduced in D3-D9 hpg mice comparing to WT littermates.

CONCLUSION

Gonadotrophin deficiency reduced D9 germ cells on BM indicating impaired gonocyte transformation into SSC. This suggests that gonadotrophins may mediate gonocyte transformation during minipuberty.

Cryptorchidism, gonocyte development, and the risks of germ cell malignancy and infertility: A systematic review

BACKGROUND/AIM

Cryptorchidism, or undescended testis (UDT) occurs in 1%-4% of newborn males and leads to a risk of infertility and testicular malignancy. Recent research suggests that infertility and malignancy in UDT may be caused by abnormal development of the neonatal germ cells, or gonocytes, which normally transform into spermatogonial stem cells (SSC) or undergo apoptosis during minipuberty at 2-6 months in humans (2-6 days in mice). We aimed to identify the current knowledge on how UDT is linked to infertility and malignancy.

METHODS

Here we review the literature from 1995 to the present to assess the possible causes of infertility and malignancy in UDT, from both human studies and animal models.

RESULTS

Both the morphological steps and many of the genes involved in germ cell development are now characterized, but the factors involved in gonocyte transformation and apoptosis in both normal and cryptorchid testes are not fully identified. During minipuberty there is evidence for the hypothalamic-pituitary axis stimulating gonocyte transformation, but without known direct control by LH and androgen, although FSH may have a role. An arrested gonocyte maybe the origin of later malignancy at least in syndromic cryptorchid testes in humans, which is consistent with the recent finding that gonocytes are normally absent in a rodent model of congenital cryptorchidism, where malignancy has not been reported.

CONCLUSION

The results of this review strengthen the view that malignancy and infertility in men with previous UDT may be caused by abnormalities in germ cell development during minipuberty.

TYPE OF STUDY

Systematic review (secondary, filtered) LEVEL OF EVIDENCE: Level I.

[German guideline on undescended testis-what is relevant in daily routine?]

With an incidence of 0.7-3% in male infants, undescended testicles is one of the most common congenital anomalies. In the first 6 months of life, the testicles may spontaneously descend in up to 70% of individuals. If the testicle is not in a scrotal position afterwards, fertility can gradually be reduced and the risk of a testicular tumor increases. Therefore, the current German guideline for undescended testis recommends that therapy should be take place between 6 and 12 months of life. After extensive information on the advantages and disadvantages, hormone therapy with the aim of a descensus or in those with bilateral anomaly with the aim of improving the germ cell pool can be offered. After the first year of life, hormone therapy is obsolete. Otherwise, surgical intervention is the treatment of choice. In the case of gliding or deep inguinal testis via scrotal or inguinal access, in the case of nonpalpable and sonographically undetectable testis, laparoscopy is carried out for diagnosis and simultaneous therapy. In the first postoperative year, adequate follow-up should be done to detect a re-ascensus and/or insufficient growth. Regular self-examinations from the age of 15 serve for the early detection of a testicular tumor that occurs only very rarely (approximately 0.003%).

Development and Disease-Dependent Dynamics of Spermatogonial Subpopulations in Human Testicular Tissues

Cancer therapy and conditioning treatments of non-malignant diseases affect spermatogonial function and may lead to male infertility. Data on the molecular properties of spermatogonia and the influence of disease and/or treatment on spermatogonial subpopulations remain limited. Here, we assessed if the density and percentage of spermatogonial subpopulation changes during development (n = 13) and due to disease and/or treatment (n = 18) in tissues stored in fertility preservation programs, using markers for spermatogonia (MAGEA4), undifferentiated spermatogonia (UTF1), proliferation (PCNA), and global DNA methylation (5mC). Throughout normal prepubertal testicular development, only the density of 5mC-positive spermatogonia significantly increased with age. In comparison, patients affected by disease and/or treatment showed a reduced density of UTF1-, PCNA- and 5mC-positive spermatogonia, whereas the percentage of spermatogonial subpopulations remained unchanged. As an exception, sickle cell disease patients treated with hydroxyurea displayed a reduction in both density and percentage of 5mC- positive spermatogonia. Our results demonstrate that, in general, a reduction in spermatogonial density does not alter the percentages of undifferentiated and proliferating spermatogonia, nor the establishment of global methylation. However, in sickle cell disease patients’, establishment of spermatogonial DNA methylation is impaired, which may be of importance for the potential use of this tissues in fertility preservation programs.

Xeno-Free Propagation of Spermatogonial Stem Cells from Infant Boys

Spermatogonial stem cell (SSC) transplantation therapy is a promising strategy to renew spermatogenesis for prepubertal boys whose fertility is compromised. However, propagation of SSCs is required due to a limited number of SSCs in cryopreserved testicular tissue. This propagation must be done under xeno-free conditions for clinical application. SSCs were propagated from infant testicular tissue (7 mg and 10 mg) from two boys under xeno-free conditions using human platelet lysate and nutrient source. We verified SSC-like cell clusters (SSCLCs) by quantitative real-time polymerase chain reaction (PCR) and immune-reaction assay using the SSC markers undifferentiated embryonic cell transcription factor 1 (UTF1), ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCHL1), GDNF receptor alpha-1 (GFRα-1) Fα and promyelocytic leukaemia zinc finger protein (PLZF). The functionality of the propagated SSCs was investigated by pre-labelling using green fluorescent Cell Linker PKH67 and xeno-transplantation of the SSCLCs into busulfan-treated, therefore sterile, immunodeficient mice. SSC-like cell clusters (SSCLCs) appeared after 2 weeks in primary passage. The SSCLCs were SSC-like as the UTF1, UCHL1, GFRα1 and PLZF were all positive. After 2.5 months’ culture period, a total of 13 million cells from one sample were harvested for xenotransplantation. Labelled human propagated SSCs were identified and verified in mouse seminiferous tubules at 3–6 weeks, confirming that the transplanted cells contain SSCLCs. The present xeno-free clinical culture protocol allows propagation of SSCs from infant boys.

Surgical Management of Undescended Testis - Timetable and Outcome: A Debate

Around 1.4-3.8% of boys in the Western world are operated because of cryptorchidism. This means that orchidopexy remains one of the most common surgical procedures performed in boys. As a consequence, several consensus reports, guidelines, and reviews dealing with the management of cryptorchidism have been published recently. Based on our research and 30 years' experience with the management of cryptorchidism, the intention of the present publication is to advise on the surgical management and comment on the expected outcome, especially with focus on the controversies related to guidelines and reviews. Except for late referral and waiting lists, which may be practical problems, there is no reason to postpone orchidopexy for nonsyndromic congenital cryptorchid testes beyond 6 months. There is good evidence that such strategy improves the fertility potential and decreases the risk of testicular cancer. In cases with genuine gonadotropin insufficiency, early surgical correction is not enough and adjuvant LH-RH treatment should be implemented to improve the fertility potential. Cryopreservation may be an option in case of treatment failure of adjuvant LH-RH. A prerequisite for such management includes serum hormone assessment and evaluation of testicular biopsies at orchidopexy. Ascended testes contribute to 20-60% of operative cases and should be treated when diagnosed.

Timing of orchidopexy at a tertiary center in Saudi Arabia: reasons for late surgery

BACKGROUND

Orchidopexy should be performed during the first 18 months of life to decrease the risk of infertility and tumor formation. In our center, the timing of surgical correction varies depending on the availability of an operating room.

OBJECTIVES

Evaluate whether orchidopexy performed for patients referred to our center is done within the recommended time period and to determine causes for delay.

DESIGN

Retrospective descriptive study.

SETTING

Pediatric urology department of a tertiary care center.

SUBJECTS AND METHODS

We retrospectively reviewed the charts of patients charts who underwent orchidopexy at our center from 2000 to 2010. We assessed referral time and waiting list time, which were subdivided as follows: from referral to first visit and from first visit to surgery. We included patients younger than 14 years and excluded pa.tients with comorbidities that affected the timing of referral and surgi.cal treatment.

MAIN OUTCOME MEASURES

Referral time period and waiting list time for surgical correction of patients presented with undescended testis.

SAMPLE SIZE

128 RESULTS: After exclusion of 32 patients because of comorbidities, we describe 128 who underwent surgery for cryptorchidism at our center. The median (interquartile range, minimum-maximum) for age at sur.gery was 46.7 months (24.4-83.4, 3.1-248.6]). The median (IQR) referral occurred at an age of 25.3 months (4.1-65.5). The median (IQR) waiting list time was 15.2 months (8.1-23.3). The median (IQR) waiting time from referral to the first visit was 4.1 months (1.0-8.2). The median wait.ing time from the first visit to surgery was 8.1 months (3.8-17.5).

CONCLUSIONS

The age at the time of surgery at our center was far from ideal because of late referrals. A structured program offered by our National Health Service to educate referring physicians is necessary. Community health initiatives must emphasize prompt referral to reduce the impact of delayed surgery.

LIMITATIONS

Lack of data on the type of referring physician (i.e., general practitioner, pediatrician, surgeon, urologist).

CONFLICT OF INTEREST

None.

Advantage of early orchiopexy for undescended testis: Analysis of testicular growth percentage ratio in patients with unilateral undescended testicle

This study reports the experience of our tertiary referral center and proposes a new indicator, the growth percentage ratio (GPR), for determining the optimal timing of surgical intervention. A retrospective review of boys who underwent orchiopexy for undescended testis from 2001 to 2013 was conducted. We analyzed testicular volumes in different age groups using the UDT to normally descended testis ratio and testicular GPR. A total of 134 boys with unilateral undescended testicle underwent regular ultrasonography follow-up examinations for more than a mean of 3.9 years. Forty-five (33.4%) of them underwent orchiopexy before the age of one year. Orchiopexy at this age resulted in a GPR (2.02 ± 0.40) that was significantly higher than the GPRs in the second (1 < age ≤ 2 years, 1.25 ± 0.13, p = 0.004) and third (age > 2 years, 1.24 ± 0.14 p = 0.008) age groups. The undescended testicle grew faster when orchiopexy was performed before one year of age. Orchiopexy performed within one year from birth significantly accelerates the growth of the UDT, as determined using the GPR, compared to other age groups. The present clinical evidence indicates that orchiopexy should be performed before one year of age.

Pre- and postoperative status of gonadotropins (FSH and LH) and inhibin-B in relation to testicular histopathology at orchiopexy in infant boys with unilateral undescended testes

PURPOSE

In recent publications of boys with cryptorchidism, gonadotropins are higher and serum inhibin-B lower than normal. To some extent, serum values of inhibin-B reflect the state of germinative epithelium in cryptorchid testes. The aim of the present study was to evaluate the impact of unilateral orchiopexy on levels of gonadotropins and inhibin-B and correlate the hormone findings to the histopathology of the unilateral undescended testis.

METHODS

50 boys (mean age: 1 year and 2 months) operated for unilateral cryptorchidism had blood samples for serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and inhibin-B taken preoperatively and 3 months to 2 years postoperatively. Testicular biopsies were performed at orchiopexy. The total germ cell number per transverse tubule and presence of adult dark spermatogonia were estimated.

RESULTS

Preoperatively, 8 patients had impaired inhibin-B levels. In contrast with the expected normal physiological decline, 16 patients had an absolute rise in serum inhibin-B level postoperatively. The 4 patients who normalized the preoperative impaired serum level of inhibin-B all had low germ cell number in the testis at time of operation. Nine patients had preoperatively elevated serum levels of both LH 0.5-2.3 IU/l (mean: 1.0 IU/l) and FSH 1.3-2.2 IU/l (mean: 1.6 IU/l). Eight of these patients normalized both LH and FSH serum values postoperatively. None of the 4 boys with impaired inhibin-B level that did not normalize after surgery had elevated gonadotropins.

CONCLUSION

Orchiopexy in unilateral cryptorchidism had a clear impact on the serum level of inhibin-B and gonadotropins of 32% and 16%, respectively.

Effects on normalized testicular atrophy index (TAIn) in cryptorchid infants treated with GnRHa pre and post-operative vs surgery alone: a prospective randomized trial and long-term follow-up on 62 cases

PURPOSE

The aim of this study was to investigate the effects of gonadotropin releasing hormone analog (GnRHa) therapy on normalized testicular atrophy index (TAIn) using gonadorelin before and after orchiopexy.

METHODS

62 infants with 87 undescended testes (UDT) were prospectively assigned to two homogeneous groups according to age, position of UDT and TAIn. The patients were randomized to receive either orchiopexy alone or orchiopexy combined with GnRHa as nasal spray at 1.2 mg daily for 4 weeks before surgery and 4 weeks after surgery. Surgical approaches were relative to the position of the UDT: Shoemakers technique in proximal-UDT and Bianchi technique in distal-UDT. All the patients were evaluated clinically and sonographically 1 month before surgery, at the time of surgery, 1 month, 6 months and 5 years after surgery.

RESULTS

Ultrasound data in our study have shown a statistically significant decrease of TAIn in children given additional HT only after 5 years of follow-up, in unilateral cases and in the entirety of treated patients; in bilateral cases this difference was not statistically significant.

CONCLUSION

Patients with a TAIn >20% treated with preoperative and post-operative GnRHa therapy have a significant increase in testicular volume after 5 years of follow-up, as shown by the relative reduction of TAIn values.

Cryptorchidism --disease or symptom?

Testes descend to the scrotum normally before birth. When they fail to do so, the boy is cryptorchid and has an increased risk for testicular germ cell cancer and subfertility later in life. Early correction of maldescent by orchiopexy operation improves the spermatogenetic capacity of the testis but does not return the testicular cancer risk to the control level. Testicular descent is regulated by testis-derived hormones testosterone and insulin-like peptide 3. Cryptorchidism can therefore be considered a symptom of impaired testicular function that may also be linked to other testicular diseases, such as germ cell cancer and subfertility. Early orchiopexy can alleviate the effects of cryptorchidism on spermatogenesis, but alertness for testicular cancer should be maintained. In searching the genetic and environmental reasons for these diseases, it is useful to consider their connection with each other.

The regulation of testicular descent and the effects of cryptorchidism

The first half of this review examines the boundary between endocrinology and embryonic development, with the aim of highlighting the way hormones and signaling systems regulate the complex morphological changes to enable the intra-abdominal fetal testes to reach the scrotum. The genitoinguinal ligament, or gubernaculum, first enlarges to hold the testis near the groin, and then it develops limb-bud-like properties and migrates across the pubic region to reach the scrotum. Recent advances show key roles for insulin-like hormone 3 in the first step, with androgen and the genitofemoral nerve involved in the second step. The mammary line may also be involved in initiating the migration. The key events in early postnatal germ cell development are then reviewed because there is mounting evidence for this to be crucial in preventing infertility and malignancy later in life. We review the recent advances in what is known about the etiology of cryptorchidism and summarize the syndromes where a specific molecular cause has been found. Finally, we cover the recent literature on timing of surgery, the issues around acquired cryptorchidism, and the limited role of hormone therapy. We conclude with some observations about the differences between animal models and baby boys with cryptorchidism.

What is new in cryptorchidism and hypospadias--a critical review on the testicular dysgenesis hypothesis

It has been hypothesized that poor semen quality, testis cancer, undescended testis, and hypospadias are symptoms of one underlying entity--the testicular dysgenesis syndrome--leading to increasing male fertility impairment. Though testicular cancer has increased in many Western countries during the past 40 years, hypospadias rates have not changed with certainty over the same period. Also, recent studies demonstrate that sperm output may have declined in certain areas of Europe but is probably not declining across the globe as indicated by American studies. However, at the same time, there is increasing recognition of male infertility related to obesity and smoking. There is no certain evidence that the rates of undescended testes have been increasing with time during the last 50 years. In more than 95% of the cases, hypospadias is not associated with cryptorchidism, suggesting major differences in pathogenesis. Placental abnormality may occasionally cause both cryptorchidism and hypospadias, as it is also the case in many other congenital malformations. The findings of early orchidopexy lowering the risk of both infertility and testicular cancer suggest that the abnormal location exposes the cryptorchid testis to infertility and malignant transformation, rather than there being a primary abnormality. Statistically, 5% of testicular cancers only are caused by cryptorchidism. These data point to the complexity of pathogenic and epidemiologic features of each component and the difficulties in ascribing them to a single unifying process, such as testicular dysgenesis syndrome, particularly when so little is known of the actual mechanisms of disease.

Regional differences in maturation of germ cells of cryptorchid testes: role of environment

OBJECTIVE

To investigate differences in maturation of germ cells in cryptorchid testes in three different regions.

PATIENTS AND METHODS

A total of 103 consecutive patients were operated for unilateral undescended testis in Vojvodina, from March 2006 until September 2007, and had a testicular biopsy performed. Germ cells were counted, and the presence of Ad spermatogonia was noted. Biopsies were compared to biopsies of similar patients from two different regions: Philadelphia, USA (130), and Liestal, Switzerland (55 patients).

RESULTS

In Vojvodina, 84.5% of patients had Sertoli cells only, or some spermatogonia, but no Ad spermatogonia, and 15.5% had Ad spermatogonia. In Philadelphia, 59.3% of patients had poor testicular histology, and 40.7% had Ad spermatogonia. In Liestal, 61.8% of patients had no, or some, spermatogonia, but no Ad spermatogonia, and 38.2% had Ad spermatogonia. There was a difference (p = 0.000025) between the patients with normal testicular histology from Philadelphia and those from Vojvodina, as well as between the patients from Vojvodina and Liestal (p = 0.0027).

CONCLUSION

The reduction in the number of germ cells in patients with cryptorchidism from Vojvodina is more pronounced than patients from either Switzerland or USA. This is a unique observation, since such a study has not been published yet.

Reproductive outcome of men with azoospermia due to cryptorchidism using assisted techniques

The aetiology of cryptorchidism is still undiscernible in the majority of cases. It has long been argued that cryptorchidism reflects a primary testicular maldevelopment, where the contralateral scrotal testis also suffers from aspermatogenesis and low spermatogonia count. The aim of the study was to determine the reproductive outcome of ex-cryptorchid men with azoospermia post-orchidopexy after testicular sperm extraction (TESE) and intracytoplasmatic sperm injection (ICSI). In a retrospective analysis, we compared the sperm retrieval, fertilization, pregnancy and live birth rates after ICSI of consecutive ex-cryptorchid azoospermic patients (n = 15) undergoing TESE between Jan 2000 and Dec 2007 vs. non-cryptorchid azoospermic men (n = 142). Sperm retrieval rate of ex-cryptorchid men by TESE (66%) was comparable with non-cryptorchid men (47%) (p = 0.15) despite significantly higher FSH levels (30.7 +/- 25.4 vs. 17.9 +/- 14.8 respectively) (p = 0.018) and a more prevalent histopathology diagnosis of aspermatogenesis (75% vs. 40%, p = 0.046). Fertilization (43.3%), pregnancy (30%) and live birth (20%) rates after TESE-IVF-ICSI in the ex-cryptorchid group were not different from the non-cryptorchid group (48.7, 43 and 29%, p = 0.26, p = 0.21, p = 0.29 respectively). We conclude that the reproductive outcome of ex-cryptorchid men with azoospermia post-orchidopexy employing TESE-IVF-ICSI is comparable with non-cryptorchid azoospermic men.

Insulin-like factor 3 levels in cord blood and serum from children: effects of age, postnatal hypothalamic-pituitary-gonadal axis activation, and cryptorchidism

CONTEXT

The Leydig cell hormone insulin-like factor 3 (INSL3) is important for testicular descent. Currently INSL3 levels in cord blood, in serum throughout childhood, and in relation to congenital cryptorchidism are unknown.

OBJECTIVE

The objective of the study was to characterize INSL3 levels in cord blood during the postnatal activation of the hypothalamic-pituitary-gonadal axis and in later childhood in normal boys and girls and cryptorchid boys.

DESIGN AND PARTICIPANTS

Serum from 267 3-month-old boys of a prospective study with standardized cryptorchidism classification was analyzed for INSL3 (of these, 99 also had cord blood samples). Testicular position was known in 151 controls and 54 transiently cryptorchid and 62 persistently cryptorchid subjects. Eight infant girls, 26 boys (4.1-10.1 yr), and 13 girls (3.7-8.7 yr) were also included.

OUTCOME MEASURE

INSL3, age, testicular position, LH, and testosterone were measured.

RESULTS

INSL3 levels were significantly higher (P < 0.001) in cord blood and 3-month-old boys as compared with older prepubertal boys. At 3 months of age, INSL3 correlated significantly with LH in healthy boys. Cord blood INSL3 was significantly reduced in persistently cryptorchid boys (P = 0.001), and 3-month-old persistently cryptorchid boys had a significantly increased LH to INSL3 ratio (P = 0.014). INSL3 was unmeasurable in girls at all ages.

CONCLUSIONS

In boys, early postnatal INSL3 is markedly higher as compared with later childhood, presumably because it is stimulated by the transient postnatal LH peak. INSL3 was unmeasurable in girls at all ages. Reduced cord blood INSL3 and an increased LH to INSL3 ratio at 3 months of age in persistently cryptorchid boys suggest impaired Leydig cell function in cryptorchid boys already in the perinatal period.

Orchidopexy and its impact on fertility

We critically analysed the factors known to influence the fertility potential after orchidopexy in children. A comprehensive literature review of all publications in the English language listed in Medline using the words cryptorchidism, undescended testis, orchidopexy, fertility, semen analysis and surgery from 1970 to 2005. In unilateral ectopic, canalicular and emergent testes, as long as the surgery is carried out in early childhood, fertility outcome is good (>90%). The majority of the bilateral abdominal testes are infertile. While unilateral abdominal testes and unilateral absent or vanishing testes have favourable fertility potential, quantification has proven difficult. Despite multiple studies, fertility in crypt orchid tests is still an uncertain issue. Hormonal treatment in conjunction with early surgical correction has not been fully explored. We recommend orchidopexy soon after 6-7 months of age, corrected for term, to maximise the future fertility potential.

Influence for testicular development and histological peculiarity in the testes of flutamide-induced cryptorchid rat model

OBJECTIVES

To investigate influence for the testicular development and to assess the usefulness as an animal model, cryptorchid rats were induced by exposure to flutamide during the fetal period and their testes examined histologically.

METHODS

Flutamide was injected into the abdomen of pregnant rats for 7 days from the 14th to 20th day of gestation. The male offspring in which cryptorchidism was observed at 28 days after birth were defined as the model rats. They were divided into four groups by dosage of flutamide (2.5 mg, 5 mg, 7.5 mg, 15 mg per day), and their testicular weight, spermatogenesis (modified Johnsen score), and germ cell apoptosis were examined histochemically at 10 weeks after birth.

RESULTS

The incidence of cryptorchidism including both unilateral and bilateral in the 2.5, 5, 7.5 and 15-mg flutamide groups was 58.3%, 81.9%, 93.6% and 91.0%, respectively. In the model rats, the undescended testes were located at the caudal end of the abdominal cavity, and these testes weighed less than the contra-descended testes in each group. Histologically, apoptotic cells were markedly increased, the seminiferous tubules were degenerated and disturbance of spermatid differentiation was observed in the undescended testes compared with the normal or contra-lateral descended testes.

CONCLUSIONS

We found out that the incidence of undescended testes increased in a flutamide dose-dependent manner. The findings of histological examination were independent of the administrated dose of flutamide and it is suggested that exposure of the testes to abdominal temperature causes spermatogenic arrest with germ cell apoptosis. The present animal model indicates high incidence of above 90%, has no surgical stress and dose not require special techniques. We believe that the present model is a useful tool for the understanding of pathogenesis and treatment of cryptorchidism and further biological research into spermatogenesis.

The relation of germ cells per tubule in testes, serum inhibin B and FSH in cryptorchid boys

At bilateral orchiopexy bilateral biopsies may be indicated to determine fertility potential. It is currently unknown if the serum inhibin B levels at time of orchiopexy reflect the testicular status of the bilaterally cryptorchid child. The aim of this study was to relate the results of inhibin B and FSH measurements with testicular biopsy parameters in bilateral cryptorchid boys. Included were 25 boys with bilateral cryptorchidism, median 2.5 years (9 months to 5.5 years) at surgery for bilateral cryptorchidism with simultaneous testicular biopsies, and blood sample for inhibin B and FSH. The number of spermatogonia and gonocytes was measured in 100 tubular transverse sections, the S/T and the mean-S/T of the patient was found, and expressed as percent of lowest normal value. Inhibin B and FSH were measured and related to age-specific values. Forty percent (10/25) of the patients had very low mean-S/T (mean-S/T<10% of lowest normal-value). Inhibin B was decreased in 24% (6/25) of the patients, all with decreased mean-S/T, predominantly with a mean-S/T<10% of lowest normal-value (p<0.05). There was a negative correlation between inhibin B and FSH (p<0.05). In cases of mean-S/T<10% of lowest normal-value and decreased inhibin B, we found increased FSH in 9% (2/22) of the patients and hypergonadotropic hypogonadism was suspected. Low FSH was found in 5% (1/22) of the patients and hypogonadotropic hypogonadism was suspected. Low inhibin B predicts a serious condition in respect of infertility. Low FSH and inhibin B indicates examination for hypogonadotropic hypogonadism. In bilateral cryptorchid boys inhibin B levels correlated negatively to FSH.

Testicular growth from birth to two years of age, and the effect of orchidopexy at age nine months: a randomized, controlled study

AIM

To study whether surgical treatment at age 9 mo in boys with congenital unilaterally palpable undescended testes (cryptorchidism) is followed by improved growth of the previously retained testes compared to non-treatment.

METHODS

At the age of 6 mo, 70 boys were randomized to surgical treatment at 9 mo and 79 boys to treatment at 3 y of age. The boys were then followed at 12 and 24 mo. Ultrasonography was used to determine testicular volume.

RESULTS

After orchidopexy, the previously retained testes resumed growth and were significantly larger than the non-operated testes at 2 y (0.49 ml vs 0.36 ml, p<0.001). Testicular growth after orchidopexy was also demonstrated by a higher mean ratio between the previously retained and the scrotal testes of the individual boys at 2 y: 0.84 for the surgically treated group, compared to 0.63 for the untreated group (p<0.001).

CONCLUSION

Surgery at 9 mo has a beneficial effect on the growth of previously undescended testes.

Testicular development in the complete androgen insensitivity syndrome

The complete androgen insensitivity syndrome (CAIS), caused by mutations in the androgen receptor (AR) gene, is associated with abnormal testicular development and an increased risk of germ cell malignancy. Previous histological studies in CAIS have selected patients purely on the basis of clinical diagnosis and were mostly based on small numbers, many of whom were post-pubertal. Here, we present 44 cases of CAIS, each with molecular pathological confirmation of an AR mutation. The median age at gonadectomy was 5.5 years (5.5; IQR 1-13). We have been able, therefore, to investigate testicular development in infancy, childhood and puberty, and estimate the incidence of premalignant change in this series. In addition, we have investigated whether the presence of epididymides and/or vasa deferentia in CAIS, previously shown to be associated with residual activity of mutant ARs, is related to a particular testicular phenotype. Epididymides/vasa deferentia were present in 36% of cases and these patients showed varying degrees of seminiferous tubule maturation at puberty above those without epididymides/vasa deferentia (p = 0.003). There were no other histological differences between these patient groups. In both groups, features of testicular degeneration and dysgenesis were present and germ cell development was delayed, with prolonged expression of the gonocyte markers, placental-like alkaline phosphatase and activator protein-2gamma. Germ cell numbers rapidly declined after the first year of life (R(2) = 0.42). Only two cases of carcinoma in situ were identified in our study and both patients were postpubertal (17 and 53 years). From these results and the literature, we conclude that the risk of premalignant change in germ cells is low before and during puberty. Patients can be advised, therefore, that gonadectomy can be delayed to allow for a natural puberty, with low risk of malignant transformation. Our study only included one patient over 18 years, so we cannot comment on the risk of malignant transformation in later life.

Cryopreservation of intact testicular tissue from boys with cryptorchidism

BACKGROUND

Boys with cryptorchidism often face fertility problems in adult life despite having orchiopexy performed at a very young age. During this operation, a biopsy of the testis is normally taken in order to evaluate their infertility potential and the presence of malignant cells. This study evaluated the morphology and functional capacity of cryopreserved testes biopsies and their possible use in fertility preservation.

METHODS

Biopsies from 11 testes (eight boys) were obtained. Each biopsy was subdivided into six pieces and two pieces were frozen in each of two different cryoprotectants. One fresh and two cryopreserved pieces were cultured for 2 weeks. All pieces were prepared for histology. Used culture media were analysed for testosterone and inhibin B concentrations.

RESULTS

The morphology of the fresh and frozen-thawed samples was similar, with well-preserved seminiferous tubules and interstitial cells. A similar picture appeared after 2 weeks of culture, but a few of the cultured biopsies contained small necrotic areas. The presence of spermatogonia was verified by c-kit-positive immunostaining. Production of testosterone and inhibin B (ng/mm(3) testis tissue) in the frozen-thawed pieces was on average similar to that of the fresh samples.

CONCLUSIONS

Intact testicular tissue from young boys with non-descended testes tolerates cryopreservation with surviving spermatogonia and without significant loss of the ability to produce testis-specific hormones in vitro. It may be an option to freeze part of the testis biopsy, which is routinely removed during the operation for cryptorchidism, for fertility preservation in adult life.

Prepubertal unilateral spermatic vessel ligation decreases haploid cell population of ipsilateral testis postpubertally in rats

DNA flow cytometry is a sensitive and rapid technique to evaluate the germ cell maturation of testis. The haploid cell population of testis specifically denotes testicular maturation. High ligation of spermatic vessels (HLSV) and low ligation of spermatic vessels (LLSV) have been described in the surgical treatment of high undescended testis. Estimation of germ cell population of testis after these maneuvers has not been performed so far by DNA flow cytometry; hence this study was designed. Thirty male rats, aged 30 days, were randomized into three groups. Group I underwent sham surgery; group II underwent unilateral HLSV-ligation and division of main spermatic vessels, similar to the Fowler-Stephens technique; and group III underwent unilateral LLSV-ligation and division of main spermatic vessels close to the testis, similar to the Koff and Sethi technique. Thirty days later, the ipsilateral testes were harvested, and haploid, diploid, and tetraploid cells were counted by DNA flow cytometry. The mean (+/-SD) percentage of the haploid cell population was 68.7+/-4.8, 49.3+/-6.5, and 50.8+/-6.4 in groups I, II, and III, respectively. There was a significant (p<0.05) decrease in haploid cell population between groups I and II and between groups I and III. However, there was no significant difference between groups II and III. In conclusion, prepubertal HLSV as well as LLSV decreases the haploid cell population of ipsilateral testis in rats. LLSV has no advantage over HLSV.

VOLUMETRIC AND HISTOLOGICAL FINDINGS IN INTRA-ABDOMINAL TESTES BEFORE AND AFTER DIVISION OF SPERMATIC VESSELS

PURPOSE

Increased use of video laparoscopy in the diagnosis and treatment of the impalpable testis has encouraged use of the 2-stage Fowler-Stephens orchiopexy. To date, however, few limited studies exist to indicate whether clipping and division of the spermatic vessels alone may cause histological abnormalities in the intra-abdominal testis.

MATERIALS AND METHODS

We evaluated histology and volume of 44 intra-abdominal testes in 35 patients between 4 months and 14 years old at stages 1 and 2 of the Fowler-Stephens procedure.

RESULTS

There was a significant reduction in the number of spermatogonia and seminiferous tubules 6 months after ligation and division of the spermatic vessels. No differences were found in the number of Sertoli cells or testicular volume before and after clipping and division of the spermatic vessels.

CONCLUSIONS

Ligation of the spermatic vessels during stage 1 orchiopexy for intra-abdominal testicles is associated with a significant reduction of spermatogonia. However, no significant changes were observed in the volumetric characteristics of the testicles. Further studies are necessary to evaluate the repercussions of these changes in future fertility.

A comparison of palpable and impalpable cryptorchid testes using CD-99 immunohistochemistry

OBJECTIVE

To compare the clinical and morphological features of impalpable and palpable cryptorchid testes, as there is debate about how much effort is appropriate to bring an impalpable undescended testicle into the scrotum.

PATIENTS AND METHODS

We reviewed retrospectively 189 cases of undescended testicles in 168 patients who were explored surgically by one surgeon between August 1997 and September 2000. Operative findings of palpability, testicular size and location were collected. The mean tubular diameter (MTD), tubular fertility index (TFI) and mean number of germ cells per tubule (MGCT) were calculated using immunohistochemistry for CD-99, a Sertoli-cell marker, to classify germ cells more accurately.

RESULTS

Sixty-three testes (33%) were impalpable; the median age at the time of surgical exploration was 23 months for both groups. The mean (sd) testicular volume for the impalpable and palpable groups were 0.83 (0.38) and 1.22 (0.54) mL, respectively. Using fitted curves of size vs age, impalpable testes were smaller than palpable testes at all ages, with the difference nearly statistically significant (P < 0.06). The MTD, TFI and MGCT decreased with age in both groups, with no statistically significant differences between the groups. A sub-analysis of abdominal and extra-abdominal testes confirmed no significant differences.

CONCLUSION

Impalpable testes are smaller at the time of exploration than palpable cryptorchid testes. However, histological factors predict that impalpable testes have a significant chance of future fertility and therefore orchidopexy is appropriate. CD-99 immunohistochemistry makes objective morphological information easier to obtain.

Association between testicular dysgenesis syndrome (TDS) and testicular neoplasia: evidence from 20 adult patients with signs of maldevelopment of the testis

Based on a well established association between testicular cancer and undescended testis and more recent publications on epidemiological links between these disorders and male infertility, we proposed the existence of a testicular dysgenesis syndrome (TDS). In most cases TDS presents with impaired spermatogenesis, only in rare cases the full range of its signs, including genital malformations and testicular cancer can be seen in one patient. In order to further corroborate our hypothesis about the presence of testicular dysgenesis in patients with testicular abnormalities, we decided to re-analyse recent testicular biopsies derived from patients with infertility, hypospadias and undescended testis. We searched for histological signs of testicular dysgenesis: microliths, Sertoli-cell-only tubules, immature seminiferous tubules with undifferentiated Sertoli cells, and tubules containing carcinoma in situ (CIS) cells. We identified 20 patients who fulfilled the histological criteria for testicular dysgenesis, 9 of whom were diagnosed with uni- or bilateral testicular germ cell neoplasia, and the remaining ones with subfertility. The presence of CIS was detected in 5 patients (3 of them with overt contralateral germ cell tumours). In all but one of the CIS cases, at least one additional sign of testicular dysgenesis was detected. Clinical records of all patients were subsequently analysed. The majority of cases had oligozoospermia or azoospermia. Their reproductive hormone profiles correlated with the results of semen sampling and testicular histology. In conclusion, our study of 20 patients with various reproductive abnormalities provided evidence that TDS is a real clinical entity. We speculate that most of these abnormalities are caused by adverse environmental effects rather than specific gene mutations.

Multinucleated spermatogonia in cryptorchid boys: a possible association with an increased risk of testicular malignancy later in life?

At birth, undescended testes contain germ cells, but after 1 year of life, a reduced number of germ cells is generally found. Microlithiasis and carcinoma-in-situ-testis occur in cryptorchid boys. Multinucleated germ cells, including at least 3 nuclei in the cell, exist in impaired spermatogenesis and in the senescent testis.

AIM OF THE STUDY

We investigated whether multinucleated spermatogonia were present in undescended testes of cryptorchid boys, and if such a pattern is associated with special clinical features.

RESULTS

Multinucleated spermatogonia occurred in 13/168 (8%) of 163 consecutive cryptorchid boys, who underwent surgery for cryptorchidism with simultaneous testicular biopsy showing seminiferous tubules. The patients with multinucleated spermatogonia more often exhibited a normal germ cell number (Fisher's exact test, p<0.0005), and were younger at surgery (Mann Whitney, p<0.005) than the rest of the patients. Before surgery, 3 patients underwent treatment with Erythropoietin because of renal failure. An intra-abdominal testis underwent clipping and division of the spermatic vessels, and a biopsy at final surgery 7 months later, exhibited multinucleated spermatogonia. In 1 case the undescended testicular position, a fixed retraction, was acquired after surgery for an inguinal hernia. Multinucleated spermatogonia were found in cases of carcinoma-in situ-testis in 2 cryptorchid boys. No case of multinucleated germ cells appeared in our normal material.

CONCLUSION

Multinucleated spermatogonia are a further abnormality present in cryptorchidism. The cryptorchid boys with multinucleated spermatogonia in general exhibited rather many germ cells. This feature may be associated with an increased risk of testicular malignancy later in life, and we propose a careful follow up regime in these cases including ultrasound examination and a testicular biopsy in cases of symptoms or clinical findings.

Estimating the testis volume during the fetal period using the stereological method

The purpose of the present study is to assess the development of seminiferous tubule volume, stromal volume and total testis volume in the human fetal testis during the fetal period using the stereological method. In this study, we examined 90 testes of 45 human fetuses with no congenital anomalies and pathologies. They were aged between 12 and 40 weeks and localized between the scrotum and the abdomen. Total testis volume, seminiferous tubule volume, and stromal volume were estimated using Cavalier Principles. The weight and density of the testes were calculated as well. During the fetal period, the testes were firstly found on the right in the 27th week and on the left in the 32nd week in the scrotum. At the end of the third trimester and full term, the migration of the testes into scrotum was completed (98%). When the second trimester, third trimester and full term fetuses were compared, the differences between testis volumes were significant (p<0.001). The density of the testes between the groups was not significant (p>0.05). Testis parameters during the fetal period were not significantly (p>0.05) different between the right and left testes localization. The correlation between the fetal testis parameters was significant (p<0.001). Towards the end of the fetal period, the rate of seminiferous tubule volume to stromal volume changed in the favor of seminiferous tubule volume. It was observed that interstitial tissue became more regular and had a good organized structure with the progress of gestational age. In the third trimester, the lumen in the seminiferous tubules became more regular and clear and the interstitial tissue had a clear appearance.

Application of ICSI for cryptorchid therapy

Recent advances are provided in assisted reproductive technology and application of ICSI as treatment for infertile patients with previous cryptorchidism. Fertility rates were 25-81% and 8-48% in patients with unilateral and bilateral cryptorchidism, respectively. With the advent of assisted reproductive technology, pregnancy was not possible without sperm. Research in humans has resulted in pregnancy and live births after the injection of haploid germ cells (round spermatids) into the oocytes. In the mouse tetraploid germ cells (primary spermatocytes), nuclei have been injected into oocytes, which undergo meiosis, forming an embryo and live young. In animal models, round spermatids from both cryptorchid and previously cryptorchid testes can initiate normal embryo development when injected into mature oocytes. These cells may be used as substitutes for mature sperm. However, cryptorchidism in humans is often associated with inherent defects of spermatogenesis. With successive breakthroughs in treatment of impaired fertility associated with cryptorchidism, there is an increased risk of genetic abnormalities in the progeny. It is incumbent on clinicians who are involved in reproductive medicine to proceed cautiously with the development and application of assisted reproductive techniques to avoid creating future generations of genetically abnormal individuals.

The growth of the testes during the fetal period

OBJECTIVE

To determine the size and position of the fetal testes during gestation.

MATERIALS AND METHODS

The study comprised 48 testes obtained from 24 human fetuses with no congenital abnormalities, aged 14-40 weeks. The development of the fetuses was evaluated by measuring the crown-rump length. Testicular size was assessed as the height, width, thickness and weight, and the position of testes determined during fetal development.

RESULTS

The testes in 11 fetuses (22 testes) aged 14-37 weeks were in the abdominal cavity; no testis had descended to the scrotum in any fetus until 27 weeks of gestation. Both testes had descended to the scrotum only in fetuses aged 33-40 weeks. There was no significant difference between right and left testicular size in 13 fetuses (26 testes) aged 27-40 weeks, but size correlated with gestational age (P<0.001).

CONCLUSION

All testes had descended to the scrotum by 33 weeks of gestation, but there was considerable variation in position from 27 weeks.