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.

Undescended testis: A roundtable discussion based on clinical scenarios - Part 1

Undescended testis (UDT, cryptorchidism) is the most common congenital anomaly of the genital tract. Despite its high incidence, the management of UDT varies between specialties (urology, pediatric surgery, pediatric urology, pediatric endocrinology). Therefore, as the European Association of Urology - Young Academic Urologists Pediatric Urology Working Group, we requested experts around the world to express their own personal approaches against various case scenarios of UDT in order to explore their individual reasoning. We intended to broaden the perspectives of our colleagues who deal with the treatment of this frequent genital malformation.

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 Inhibin-B Level at Orchidopexy and Follow-up of 280 Boys With Non-syndromic Unilateral Cryptorchid Testes

PURPOSE

An impaired germ cell number per tubular cross-section (G/T) at orchidopexy indicates a high risk of infertility. A recent study in boys with bilateral cryptorchidism showed a very high predictive value for a low serum inhibin-B level, indicating bilateral impaired G/T. Several other studies have shown a fairly strong correlation between inhibin-B and G/T. We aimed to evaluate if inhibin-B levels at orchidopexy improved at follow-up in boys with unilateral cryptorchidism.

METHODS

We included 280 boys with unilateral non-syndromic cryptorchidism at the median age of 1 year (4 months-9 years) who underwent orchidopexy. They were evaluated for serum FSH, LH and inhibin-B levels at surgery and at follow-up (median 16 months later), including multiple of the median (MoM) estimations of inhibin-B due to the age dependency of normal levels.

RESULTS

The inhibin-B MoM score improved significantly at follow-up. At orchidopexy, 59 (21%) boys had inhibin-B levels below the normal 2.5-percentile indicating impaired G/T bilaterally. At follow-up, 36% of the boys still had low inhibin-B. At orchidopexy, 221 (79%) boys had inhibin-B levels above normal 2.5-percentile and only 5% had low inhibin-B levels at follow-up. The risk of low inhibin-B levels at follow-up was significantly different between the two groups (p < 0.0001). At follow-up, totally, 32 (11%) boys had low inhibin-B levels, hereof only 3 patients with increased FSH.

CONCLUSIONS

Orchidopexy benefits the fertility potential. About 10% of boys with unilateral non-syndromic cryptorchidism may have a bilateral testicular disease reducing their fertility potential. Insufficient gonadotropin stimulation may possibly be the cause.

Robot-assisted laparoscopic varicocelectomy in a pediatric population

PURPOSE

To present our experience with robot-assisted laparoscopic varicocelectomy in a pediatric population.

METHODS

We reviewed 49 consecutive cases performed by the same experienced surgeon. One-to-four veins were ligated at the internal ring of the inguinal canal, while the testicular artery and lymphatics were spared. Information on patient characteristics, surgical time, complications, and recurrences were collected.

RESULTS

Median patient age was 14 (range 10-17) years. Forty-eight had left-sided varicoceles and one had a bilateral varicocele. Forty-five were grade 3. All patients were referred due to discomfort/pain and 20 also had reduced testicular size. The median operating time from skin incision was 48 min (31-89 min) and the median console time was 18 min (7-55 min). Forty-seven patients were discharged the same day. Two patients experienced pain and problems urinating, respectively. These issues had resolved by the first post-operative day. There were no other complications, but at 6 months, eight recurrences were noted (16%). Scrotal complaints had subsided in all patients. Catch-up growth of the affected testicles was seen in 19/20 cases.

CONCLUSION

Robot-assisted laparoscopic varicocelectomy is feasible and safe in a pediatric population but with a relatively high recurrence rate.

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).

P-468 Organotypic culture of testicular tissue from infant boys with cryptorchidism

Study question

Can organotypic culture support the survival and maturation of germ cells and niche-related cells within testicular tissue from infant boys with cryptorchidism?

Summary answer

The testicular structure and the number of germ cells were maintained during organotypic culture, whereas Sertoli cells and peritubular myoid cells (PTMCs) matured.

What is known already

Testicular tissue cryopreservation (TTC) is a strategy to safeguard the fertility of prepubertal boys who face a risk of infertility. Organotypic culture of immature testicular tissue from mice achieved production of spermatozoa. Similarly, the culture of human fetal gonads resulted in the generation of competent spermatids. However , in vitro spermatogenesis by organotypic culture of human prepubertal testicular tissue has not been achieved. It is also unknown whether germ cells as well as its niche-related cells, in testicular tissue from infant boys with cryptorchidism, can maintain and mature under in vitro conditions.

Study design, size, duration

Testicular tissue was cryopreserved from four infant boys with bilateral cryptorchidism undergoing orchidopexy (age range: 0.5-1.4 years), as part of a fertility preservation program. Culture media with and without retinoic acid were tested. Testicular fragments were harvested at 30 days and 60 days after culture and evaluated by histological assessment of tissue structure, germ cell development, and immunohistochemical staining for germ cell and somatic cell markers.

Participants/materials, setting, methods

Cryopreserved-thawed testicular tissue was cut into fragments (1-2 mm3) and placed on top of agarose gel stands and cultured at 34oC with 5% CO2 in Minimum Essential Medium-alpha supplemented with knockout serum replacement, human umbilical cord plasma, Activin A, hormones, growth factors, with or without retinoic acid. Immunohistochemical analyses were performed using germ cell markers (MAGE-A, GAGE, and VASA), Sertoli cell maturation markers (AMH, AR, SOX9), PTMC marker (alpha-SMA).

Main results and the role of chance

Following the 60-day culture, the lumen of the seminiferous tubules had developed. The number of germ cells per tubule remained stable during this period. However, no further germ cell maturation was observed. Germ cells showed different phenotypes of MAGEA, GAGE, and VASA expression with no significant difference in number. The number of SOX9-positive Sertoli cells was significantly increased from 30 days to 60 days of culture (p &lt;0.0001). No difference in AMH expression was observed, while AR expression in Sertoli cells was induced during culture. Alpha-SMA expression was detected in the PTMCs surrounding the seminiferous tubules. The two different culture conditions, with and without retinoic acid in the culture media, did not affect cell survival or maturation.

Limitations, reasons for caution

The small number of testicular biopsies available is a limitation.

Wider implications of the findings

Our organotypic culture conditions support the long-term survival of germ cells in testicular tissue from infant boys with cryptorchidism. Thus, further studies are needed to induce the maturation of germ cells under similar experimental conditions.

Trial registration number

not applicable

Serial Inhibin B Measurements in Boys with Congenital Monorchism Indicate Compensatory Testicular Hypertrophy in Early Infancy

AIM

 Congenital monorchism is considered a condition in which an initially normal testis has existed but subsequently atrophied and disappeared due to a third trimester catastrophe (presumably torsion). Since inhibin B concentrations appear related to Sertoli and germ cells number, we evaluated pre- and postoperative inhibin B of boys with congenital monorchism to determine whether the well-known hypertrophy of the contralateral testis was reflected in inhibin B concentrations.

MATERIALS AND METHODS

 Twenty-seven boys consecutively diagnosed with congenital monorchism (median age 12 months) underwent follow-up with reproductive hormones 1 year postoperatively (median age 25 months). The results were compared with inhibin B of 225 boys with congenital nonsyndromic unilateral cryptorchidism, by converting values to multiple of the median (MoM) for age in normal boys.

RESULTS

 Ten boys (37%) had blind-ending vessels and ductus deferens (vanished testis) and the remaining (63%) had testicular remnants. At the time of diagnostic procedure, monorchid boys did not have significantly lower inhibin B (median 114, range 20-208) than unilateral cryptorchid boys (136, 47-393) (p = 0.27). During follow-up, MoM values of inhibin B increased in monorchid boys (median 0.59 to 0.98) and in unilateral cryptorchid boys (0.69 to 0.89) (both p < 0.0001). Compared with the concentration at surgery, an additional 44% monorchid boys had inhibin B MoM values higher than 1.0, whereas only additional 23% of unilateral cryptorchid boys exhibited such values (p = 0.04).

CONCLUSION

 Generally, inhibin B MoM values were normalized during follow-up in boys with congenital monorchism, reflecting compensatory hypertrophy within the first 2.5 years of life. The compensatory capacity to increase was better in monorchism than in unilateral cryptorchidism.

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.

Robot-Assisted vs. Open Appendicovesicostomy in Pediatric Urology: A Systematic Review and Single-Center Case Series

INTRODUCTION

Appendicovesicostomy (APV) is the preferred choice of continent catheterizable channels in pediatric urology. The introduction of robot-assisted laparoscopic techniques has been correlated to superior cosmesis and convalescence and is now increasingly implemented for APV procedures. We aimed to perform a systematic review of the literature comparing open vs. robotic APV regarding possible differences in postoperative outcomes and to evaluate these findings with our own initial experiences with robotic APV compared to our previous open procedures.

METHODS

We evaluated the first five patients undergoing robotic APV at our institution and compared 1-year outcomes with a consecutive series of 12 patients undergoing open APV. In a systematic literature review, we screened studies from PubMed, EMBASE, and CENTRAL comparing open and robotic APV in pediatric urology (current to December 2021) and performed meta-analyses on postoperative outcomes comparing the two groups and evaluated the grade of evidence.

RESULTS

We found significantly shortened postoperative length of stay in the robotic group (p = 0.001) and comparable 1-year complication rates in robotic vs. open APV patients. We systematically screened 3,204 studies and ultimately included three non-randomized studies comparing postoperative outcomes of robotic and open APV for quantitative analysis. The open and robotic approaches performed equally well regarding overall postoperative complications, surgical reintervention, and stomal stenosis. Two of the included studies reported comparable stomal continence rates and shortened postoperative length of stay in the robotic group, in agreement with the findings in our own series.

CONCLUSION

Robotic APV is equally safe to the conventional open approach with additional advantages in postoperative hospitalization length.

O-189 Male fertility restoration by direct transplantation of human infant testicular cells into infertile recipient mouse testis

Study question

Is colonization of human gonocytes and spermatogonial stem cells (SSCs) directly transplanted to seminiferous tubules of busulfan sterilised mice testis during an 8-week period feasible? 

Summary answer

Gonocytes and SSCs from infant boys can settle on the basal membrane and form germline stem cell colonies in the seminiferous tubules of recipient mice.

What is known already

The neonatal or immature animal provides higher populations of gonocytes and/or SSCs than adults, and the number of transplanted donor SSCs directly affects the colonization rate of the recipient testes. Along with SSC transplantation restoring the recipient’s spermatogenesis, donor gonocyte was also reported to be capable of establishing spermatogenesis in rodents.

Study design, size, duration

Transplantation of human testicular cells including gonocytes and SSCs into seminiferous tubules of infertile recipient mice. We included 10 infant testis biopsies from which single-cell suspension was transplanted individually into the seminiferous tubules of 10 immunodeficient mice. The immunodeficient mouse testes were injected with busulfan to deplete germ cells. Four weeks later, we did the xenotransplantation. Then after eight weeks, we collected all mouse testes to do further analysis.

Participants/materials, setting, methods

Testis biopsies were obtained from cryptorchid boys undergoing orchidopexy. After enzymatic digestion of the testis biopsies, dissociated single-cell suspensions were pre-labeled with a green fluorescent dye. Then the single-cell suspensions were transplanted into seminiferous tubules of the infertile recipient mice. Eight weeks later, the presence of gonocytes and SSCs was determined by immunohistochemistry and whole-mount immunofluorescence.

Main results and the role of chance

Without in vitro propagation, naturally enriched human germline stem cells settled on the basal membrane of seminiferous tubules and survived in the mouse testes at least for two months demonstrating that human gonocytes and SSCs were capable of colonizing the recipient mouse seminiferous tubules.

Limitations, reasons for caution

The study samples were from infant boys with undescended testes that were more likely to contain gonocytes. It was not possible to determine which germ-cell type at transplantation resulted in the detected gonocytes and SSC colonies after xenotransplantation. Transplantation of gonocytes may include the potential risk of stem cell-related malignancy.

Wider implications of the findings

Without in vitro propagation, male germline stem cell-based transplantation could provide a relatively safe therapeutic treatment for prepubertal boys with cryptorchidism and boys diagnosed with cancer. This method could also facilitate clinical translation.

Trial registration number

not applicable

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.

Evaluation of boys with daytime incontinence by combined cystourethroscopy, voiding cystourethrography and urodynamics

Objects: Approximately, 1% of school children have daytime urinary incontinence. The symptoms may be caused by an overactive bladder (OAB). In the evaluation of boys with OAB complaints, one should consider a possible urethral cause. The aim of the study was to evaluate the value of a diagnostic regime with cystourethroscopy, voiding cystourethrography (VCUG) and urodynamic pressure-flow studies in boys with OAB complaints after unsuccessful urotherapy and pharmacological therapy. Materials and Methods: Seventy-five boys (5-14 years old) were investigated with cystourethroscopy and within 24 h thereafter VCUG followed by urodynamic combined cystometry and pressure-flow study. All boys had daytime incontinence and urgency. Results: Sixty-one boys had no suspected urethral valves at cystoscopy or VCUG, and urodynamics showed no obstructed Pdet-Qmax. All 61 boys had detrusor overactivity. Two boys had late diagnosed urethral valves. In four boys, the initial cystourethroscopy was described as normal. The VCUG indicated presence of posterior urethral valves, but urodynamics showed no obstructed Pdet-Qmax. In eight boys, the initial cystourethroscopy was described as normal whereas urodynamics showed obstructed Pdet-Qmax. In four of these boys, VCUG showed abnormalities in the sphincter area but they were not described as suspected urethral valves. At repeat cystourethroscopy, urethral valves could still not be identified. Patient follow-up regarding achievement of continence after investigation guided treatment was in accordance with the literature. Conclusions: Boys can be safely evaluated by cystourethroscopy followed by urodynamics in search for a possible urethral problem. It is our suggestion, that VCUG can be restricted to those boys where urodynamics indicates obstruction or the findings by cystourethroscopy are uncertain.

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.

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.

Laparoscopy to Assist Surgical Decisions Related to Necrotizing Enterocolitis in Preterm Neonates

Aim of the Study: Necrotizing enterocolitis (NEC) is a devastating intestinal disease that mainly affects preterm infants. Despite advancements in neonatal care, mortality of NEC remains high and controversies exist regarding the most appropriate time for surgical intervention and challenging of diagnosing NEC. Using a pig model of NEC, we aimed to examine if laparoscopy is feasible for diagnosis of NEC. Methods: Preterm caesarean-delivered piglets (n = 42) were fed with increasing amounts of infant formula up to 5 days to induce NEC. On days 3-5, we examined the intestine by laparoscopy under general anesthesia. The bowel was examined by tilting the pigs from supine position to the left and right side. Macroscopic NEC lesions were identified and graded according to a macroscopic scoring system, then a laparotomy was performed to rule out any organ injury and missed NEC lesions. Results: Visible NEC lesions (scores 4-6) were found in 26% (11/42) of the piglets. A positive predictive value of 100% was found for laparoscopy as a diagnostic marker of NEC in both colon and the small intestine. One piglet had a higher NEC score in the small intestine found at laparotomy, than at laparoscopy, resulting in a sensitivity of 67%, and a specificity of 100% for the small intestine. Conversely, both the sensitivity and specificity for colon was 100%. Acceptable levels of agreement was found, with minimal proportional bias in both colon and the small intestine for laparoscopy and laparotomy. Ultrasound examination had a lower sensitivity of 67% and specificity of 63%. All piglets were respiratory and circulatory stable during the procedure. Conclusions: In preterm piglets, laparoscopy is a feasible tool to diagnose NEC with a high positive predictive value and a high specificity.

Gonocyte transformation in congenital undescended testes: what is the role of inhibin-B in cell death?

PURPOSE

Undescended testes (UDT) are subjected to heat stress, which can disturb gonocyte transformation as well as apoptosis. This study aims to describe the apoptosis pathway occurring during minipuberty of children with unilateral (UDT), and to investigate the role of inhibin-B.

METHODS

Testicular biopsies at unilateral orchidopexy of 10 boys (6-9 months old) with normal inhibin-B (n = 5) or low inhibin-B (n = 5) were selected for immunohistochemistry and TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labelling) assay. Testicular tubules were labelled with antibodies against Anti-Müllerian hormone (AMH, Sertoli cell marker), mouse Vasa Homolog (MVH) and placental alkaline phosphatase (PLAP) (both germ cell markers), cleaved caspase3 (apoptotic marker), and followed by confocal imaging and cell counting with Fiji/ImageJ. Data were analyzed with GraphPad Prism.

RESULTS

In males with low and normal inhibin-B, there was no statistical difference (p > 0.05) in the percentage of testicular tubules containing TUNEL + cells, number of cleaved caspase3 ± germ cells/tubule, total number of germ cells/tubule, and the percentage of fibrotic tubules or number of Sertoli cells/tubule.

CONCLUSIONS

These results suggest that inhibin-B does not regulate cell death of gonocytes and further studies are required to uncover any role of inhibin-B in gonocyte transformation.

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.

Propagation of Spermatogonial Stem Cell-Like Cells From Infant Boys

Background

Gonadotoxic treatment of malignant diseases as well as some non-malignant conditions such as cryptorchidism in young boys may result in infertility and failure to father children later in life. As a fertility preserving strategy, several centers collect testicular biopsies to cryopreserve spermatogonial stem cells (SSCs) world-wide. One of the most promising therapeutic strategies is to transplant SSCs back into the seminiferous tubules to initiate endogenous spermatogenesis. However, to obtain sufficient numbers of SSC to warrant transplantation, in vitro propagation of cells is needed together with proper validation of their stem cell identity.

Materials and Methods

A minute amount of testicular biopsies (between 5 mg and 10 mg) were processed by mechanical and enzymatic digestion. SSCs were enriched by differential plating method in StemPro-34 medium supplemented with several growth factors. SSC-like cell clusters (SSCLCs) were passaged five times. SSCLCs were identified by immunohistochemical and immunofluorescence staining, using protein expression patterns in testis biopsies as reference. Quantitative polymerase chain reaction analysis of SSC markers LIN-28 homolog A (LIN28A), G antigen 1 (GAGE1), promyelocytic leukemia zinc finger protein (PLZF), integrin alpha 6 (ITGA6), ubiquitin carboxy-terminal hydrolase L1 (UCHL1) and integrin beta 1 (ITGB1) were also used to validate the SSC-like cell identity.

Results

Proliferation of SSCLCs was achieved. The presence of SSCs in SSCLCs was confirmed by positive immunostaining of LIN28, UCHL1 and quantitative polymerase chain reaction for LIN28A, UCHL1, PLZF, ITGA6, and ITGB1, respectively.

Conclusion

This study has demonstrated that SSCs from infant boys possess the capacity for in vitro proliferation and advance a fertility preservation strategy for pre-pubertal boys who may otherwise lose their fertility.

Postnatal germ cell development during first 18 months of life in testes from boys with non-syndromic cryptorchidism and complete or partial androgen insensitivity syndrome

INTRODUCTION

Neonatal testicular germ cells/gonocytes, transform into stem cells for spermatogenesis during 'minipuberty', driving change in timing of surgery. This study examined gonocyte transformation in cryptorchid testes in children ≤18 months of age with unilateral, bilateral undescended testes (UDT), complete or partial androgen insensitivity syndrome (CAIS, PAIS) [3,4].

MATERIAL AND METHODS

Testicular biopsies were taken from patients with unilateral or bilateral UDT, PAIS or CAIS, aged 10 days-18 months. These testicular sections underwent immunohistochemistry with antibodies (Oct4, Ki67, C-Kit, Sox9) followed by confocal imaging, cell counting and statistical analysis.

RESULTS

Both Sertoli cells/tubule and germ cells (GC)/tubule decreased with age, and % empty tubules (no GC) increased with age but with no significant differences between patient groups. Oct4⁺ germ cells/tubule decreased with age. There are some GCs and Sertoli cells proliferating during the first year and most proliferating Oct4⁺ germ cells (Oct4⁺/Ki67⁺) were located off tubular basement membrane.

CONCLUSION

Our study showed that Oct4 expression gradually decreased after minipuberty and transformation into spermatogonia. Germ cells and Sertoli cells undergo mitosis during the first 12 months although not abundantly. We propose that Oct4⁺ gonocyte transformation into spermatogonia via proliferation and migration to the basement membrane may be delayed in UDT.

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.

Postnatal Germ Cell Development in the Cryptorchid Testis: The Key to Explain Why Early Surgery Decreases the Risk of Malignancy

PURPOSE

 Cryptorchidism is a risk factor for testicular malignancy and surgical treatment lowers this risk. This study aimed to investigate the germ cell behavior in prepubertal cryptorchid testes using immunohistochemical markers for germ cell malignancy to understand how early orchiopexy may possibly prevent cancer developing.

MATERIALS AND METHODS

 Histology sections from 1,521 consecutive testicular biopsies from 1,134 boys aged 1 month to 16.5 years operated for cryptorchidism were incubated with antibodies including antiplacental-like alkaline phosphatase (PLAP), anti-Oct3/4, anti-C-kit, and anti-D2-40.

RESULTS

 Oct3/4 and D2-40-positive germ cells are found throughout the first 2 years of life, with declining frequency thereafter. After 2 years, they should have disappeared and may indicate neoplasia. PLAP-positive cells were seen in 57 to 82% and C-kit-positive cells in 5 to 21% of cryptorchid testes between 4 and 13 years. Not until puberty did PLAP and C-kit-positive undifferentiated spermatogonial stem cells vanish. Only 0.3% of the present material had obvious prepubertal intratubular germ cell neoplasia (ITGCN) and they all had syndromic cryptorchidism. An additional three boys (0.3%) older than 2 years had weak Oct3/4 expression in undescended testes, but all cases were D2-40 negative.

CONCLUSION

 Prepubertal ITGCN was rare and mostly seen in syndromic cryptorchidism. In nonsyndromic cryptorchidism PLAP-positive undifferentiated spermatogonial stem cells persisted in a significant proportion of nontreated undescended testes and they will be especially sensitive to long-lasting abnormally high temperature that may be the single most important cause facilitating the accumulation of mutations during cell replication and the development of ITGCN to be prevented by orchiopexy.

The Expression of Markers for Intratubular Germ Cell Neoplasia in Normal Infantile Testes

BACKGROUND

Positive immunohistochemical expression of testicular cancer markers is often reported beyond 12 months of age in cryptorchid testes, which is assumed to indicate delayed maturation of the fetal germ cells, or neoplastic changes. These findings allowed for questions as to the extent of positive reaction in normal testes. The aim of the study was to clarify the expression of these markers in a normal material up to 2 years.

METHODS

Testicular material from 69 boys aged 1-690 days, who died of causes with no association of testicular pathology. Histology sections were incubated with primary antibodies including anti-placental-like alkaline phosphatase (PLAP), anti-C-Kit, anti-D2-40, and anti-Oct3/4. The mean germ cell number per tubular transverse section (G/T) was calculated based on the G/T of both testes of every boy.

RESULTS

The mean G/T declined through the 690 days. PLAP appeared stably expressed throughout the ages studied. The likelihood of a positive reaction for C-Kit waned with increasing age within the study period. Positive staining for D2-40 and Oct3/4 was demonstrated up to 6 and 9 months respectively.

CONCLUSION

Up to 1 or 2 years of age, normal infantile testes contain germ cells positive for the immunohistochemical markers commonly utilized to aid in the detection of testicular cancer. This finding supports the concept of germ cells undergoing a continuous maturational process in a heterogeneous fashion, and that this process is not complete by 2 years of age.

Selecting Infants With Cryptorchidism and High Risk of Infertility for Optional Adjuvant Hormonal Therapy and Cryopreservation of Germ Cells: Experience From a Pilot Study

INTRODUCTION

Orchiopexy for congenital cryptorchid testes is recommended between ½ and 1 year of age to preserve testicular germ cell maturation. Early operation is not enough to preserve fertility in 22 and 36% of cases. Aim of this study was to set up a protocol for optional adjuvant hormonal therapy after orchiopexy and thereafter cryopreservation of testicular biopsies from infants with bilateral cryptorchidism and high infertility risk.

MATERIALS AND METHODS

We included 17 boys with bilateral cryptorchidism, normal FSH, and impaired germ cell number per tubular transverse section (G/T) in testicular biopsies at orchiopexy, 7 months to 3½ years old. Postoperatively, optional adjuvant LHRH (kryptocur^®) 0.2 mg/0.1 mL 2× every second day in 16 weeks were offered. Ten boys were applicable for age matching according to parent's choice of treatment regime and G/T. Five of them had kryptocur^®, and five were controls. Repeat bilateral testicular biopsy evaluation and cryopreservation were offered to all boys 12 months after primary orchiopexy. For cryopreservation, tissue pieces were incubated with a cryoprotectant with a slow program freezing.

RESULTS

Two out of five kryptorcur^®-treated boys normalized both the average G/T and the number of adult dark spermatogonia (Ad-S). Another kryptocur^®-treated boy with initial low G/T and no Ad-S increased the G/T and achieved normal number of Ad-S at time of cryopreservation. In the control group, two patients reached only normal lower range regarding the G/T and the number of Ad-S. None of boys with less than average 0.2 G/T improved significantly, whether they were kryptocur^®-treated or not.

CONCLUSION

Based on literature and the present results, we recommend adjuvant LHRH treatment to boys with cryptorchidism and insufficient genuine gonadotropin stimulation at time of surgery, as these patients have high infertility risk. Cryopreservation should be an option in case of treatment failure of adjuvant LHRH. However, to avoid repeat surgery with biopsy, some parents may choose biopsy for cryopreservation at time of the initial bilateral orchiopexy, well informed that the procedure may only be truly indicated in 22 and 36% of the cases.

Accuracy of the hypospadias diagnoses and surgical treatment registrations in the Danish National Patient Register

Purpose

The Danish National Health registers provide a valuable data source that offers unique opportunities for observational research, including studies on the congenital anomaly hypospadias. The accuracy of the diagnosis and surgical treatment registration of hypospadias in the Danish National Patient Register (DNPR) remains unknown.

Patients and methods

We randomly sampled 500 patients diagnosed with hypospadias in the DNPR from January 1, 1995 to December 31, 2012. Among these, 384 patients were also registered with surgical treatment for hypospadias. Medical records were collected and reviewed independently by two investigators. Any classification disagreements were resolved by consensus. Using the medical records as the gold standard, we estimated positive predictive values (PPVs) with 95% confidence intervals (CIs) for the hypospadias diagnoses and surgical treatment registrations overall, as well as for the clinical subtypes.

Results

We were able to retrieve medical records for 463 (92.6%) patients with hypospadias diagnoses and for 329 (85.7%) patients registered with surgical treatment. Presence of hypospadias was confirmed in 450 of 463 patients, yielding an overall PPV (95% CI) of 97.6% (95.8%–98.7%). For subtypes of hypospadias, the PPVs ranged between 37.5% and 72.7%. For surgical treatment of hypospadias, the overall PPV was 99.7% (97.9%–99.9%).

Conclusion

The validity of the registration of hypospadias diagnoses as well as surgical treatment for hypospadias in the DNPR is overall very high. For the specific subtypes of hypospadias diagnoses codes and the specific surgical treatment codes, the PPVs are lower and cautious use is warranted. However, the DNPR remains a valuable tool for future observational research on hypospadias.

Positive Oct -3/4 and D2-40 Immunohistochemical Expression in Germ Cells and Suspected Histology Pattern of Intratubular Germ Cell Neoplasia in Boys with Cryptorchidism Vanish after the Age of 2 Years

Introduction Intratubular germ cell neoplasia (ITGCN) is a precursor to testicular germ cell cancer. Adult germ cell cancer immunohistochemical markers may fail to detect ITGCN in prepubertal boys with congenital cryptorchidism, because positive immunohistochemistry is commonly seen in boys younger than the age of 2 years, where most orchiopexies are performed. The aim of the study was to evaluate the diagnostic challenge to differentiate between a histological pattern of ITGCN and a histological pattern with some atypical germ cells and all positive cancer immunohistochemical markers, but no increased risk of malignancy. Materials and Methods Histology sections from 373 testicular biopsies from 289 boys aged 1 month to 2 years operated for cryptorchidism were incubated with primary antibodies including anti-placental-like-alkaline phosphatase, antiOct-3/4, anti-C-kit, anti-D2-40, and in case of repeat biopsy with anti-stem cell factor (SCF) receptor. Results The prevalence of Oct-3/4 and D2-40-positive staining of germ cells in testicular biopsies were in age groups less than 6 months, 100% and 50%; 6-12 months, 60% and 17%; and 1-2 years, 12% and 4%. A 1 year, 1-month-old boy with Prader-Willi syndrome treated with growth hormone had ITGCN in both cryptorchid testes. In another three bilateral nonsyndromic cases, 8 months, 8 months and 1-year-old, a histological pattern in accordance with ITGCN was found. These three boys had a repeat biopsy from both testes performed at the age of 3 years, 4 months, 3.5 years, and 3 years, 10months, respectively. In all cases, the Oct-3/4 and D2-40 positive germ cells turned negative and the histological pattern normalized completely. The primary biopsies had SCF negative germ cells. Conclusion This study is valuable in identifying the age-related change in Oct-3/4 or D2-40 immunopositive germ cells in seminiferous tubules. An ITGCN-like histological pattern in nonsyndromic cryptorchidism will vanish after the age of 3 years. Even when immunohistochemistry is applied, prepubertal ITGCN is so rarely demonstrated in cryptorchid testes, that it is not plausible that ITGCN generally originates during fetal development in cryptorchidism.

Selective imaging modalities after first pyelonephritis failed to identify significant urological anomalies, despite normal antenatal ultrasounds

AIM

We investigated the consequences of applying different imaging guidelines for urological anomalies after first pyelonephritis in children with normal routine antenatal ultrasounds.

METHODS

The cohort comprised 472 children treated for their first culture-positive pyelonephritis and investigated with ultrasound and renal scintigraphy. We excluded patients with known urological anomalies and patients born before routine antenatal ultrasound. We followed the cohort for a median of 5.7 years (3.1-10.1 years) by reviewing their medical reports.

RESULTS

Urological anomalies were diagnosed in 95 patients. Dilated vesicoureteral reflux (VUR) was the predominant finding (n = 29), including nine who initially had surgery. Using imaging guidelines from the American Academy of Pediatrics would have missed 11 urological patients, including two with initial surgery, and avoided 339 scintigraphies. Using the European Association of Paediatric Urology guidance would have missed three urological patients, one with initial surgery, and avoided 46 scintigraphies. Investigating patients under two years with ultrasound and scintigraphy, and just ultrasound in children over two years, would have identified all patients initially treated with surgery and avoided 65 scintigraphies.

CONCLUSION

Dilated VUR was the dominant anomaly in a cohort with first time pyelonephritis and normal antenatal ultrasound. The optimal imaging strategy after pyelonephritis must be identified.

Robotic surgery start-up with a fellow as the console surgeon

OBJECTIVE

Owing to the encouraging data on fellowship training in robotic pyeloplasty and the documented benefits of robotic pyeloplasty, the aim of this study was to test the feasibility of starting up pediatric urological robotic surgery in a center with a limited case volume.

MATERIALS AND METHODS

The operative parameters and clinical outcome of the first 25 robotic pyeloplasties performed were compared to data on open and laparoscopic procedures from the previous 5 year period. The fellow was the only console surgeon. An experienced non-robotic pediatric urologist was supervising at the patient site.

RESULTS

The learning curve was in accordance with previously published data on fellows. The median operating time in robotic surgery was 182 min and was significantly shorter than in laparoscopic surgery (median 250 min) and the postoperative inpatient length of stay was significantly shorter after robotic surgery (median 1 day) than after both laparoscopic (median 2 days) and open surgery (median 3.5 days). For robotic cases, postoperative renography showed either stable or increased function of the hydronephrotic kidney. The only complication was in one case with ureteral orifice edema after JJ-stent removal, requiring nephrostomy for 6 weeks.

CONCLUSIONS

The benefits of overall shorter postoperative hospital stay after robotic pyeloplasty and faster operating time compared to the laparoscopic procedure are clearly in accordance with data from the recent literature. The fast learning curve for robotic pyeloplasty will allow pediatric urology fellowship programs to be integrated in the start-up phase of a pediatric robotic program even though the case material is limited. Operative success rates were in accordance with the gold standard of open surgery.

The diagnostic impact of testicular biopsies for intratubular germ cell neoplasia in cryptorchid boys and the subsequent risk of testicular cancer in men with prepubertal surgery for syndromic or non-syndromic cryptorchidism

INTRODUCTION

Cryptorchidism is a risk factor for testicular cancer in adult life. It remains unclear how prepubertal surgery for cryptorchidism impacts later development of adult testicular cancer. The aim of study was to investigate tools to identify the cryptorchid boys who later develop testicular cancer.

METHODS

The study cohort consisted of 1403 men operated prepubertally/pubertally for undescended testis between 1971 and 2003. At surgery testicular biopsies were taken from the cryptorchid testes. The boys were followed for occurrence of testicular cancer. The testicular cancer risk was compared to the risk in the Danish Population. Testicular biopsies from the boys who developed testicular cancer during follow-up underwent histological examination with specific diagnostic immunohistochemical markers for germ cell neoplasia.

RESULTS

The cohort was followed for 33,627 person years at risk. We identified 16 cases with testicular cancer in adulthood. The standardized incidence ratio was 2.66 (95% CI: 1.52-4.32). At time of primary surgery in prepubertal/pubertal age Intratubular Germ Cell Neoplasia (ITGCN) was diagnosed in 5 cases and the boys were unilaterally orchiectomized. At follow-up new immunohistochemical staining indicated ITGCN in two of the 16 cancer cases at reevaluation of the original biopsies from time of prepubertal/pubertal surgery. One had syndromic cryptorchid and developed seminoma, and another showed nonsyndromic cryptorchidism and developed embryonic teratocarcinoma. Totally, ITGCN was diagnosed in 0.5% (7/1403) of prepubertal cryptorchid boys, whereof 57% (4/7) in syndromic-cryptorchidism.

DISCUSSION

ITGCN is predominantly observed prepubertally in boys with syndromic-cryptorchidism. In nonsyndromic cryptorchidism testicular cancer develops postpubertally, generally not based on dormant germ cells of ITGCN caused by an early fetal maldevelopment.

LEVELS OF EVIDENCE

LEVEL I.

Genetic, Maternal, and Environmental Risk Factors for Cryptorchidism: An Update

Unilateral or bilateral cryptorchidism is an isolated anomaly in the majority of cases, with evidence to date suggesting that it is a complex disorder resulting from interactions between genetic and environmental factors. Population, family, and limited genome-wide association data suggest moderate genetic risk, multiple susceptibility loci, and a role for the maternal environment. Epidemiologic studies have identified low birth weight or intrauterine growth retardation as factors most strongly associated with cryptorchidism, with additional evidence suggesting that maternal smoking and gestational diabetes increase risk. Animal studies have shown that the testis regulates its own descent by secretion of hormones that stimulate differentiation of the gubernaculum, and that endocrine-disrupting chemicals (EDCs) exhibit antiandrogenic and/or estrogenic activity that alters testicular function or gubernacular response to hormonal stimulation. However, we have yet to determine the degree to which EDCs contribute to cryptorchidism risk in humans, in part due to the varying methodology used in epidemiological and exposure studies. Large populations will be required to define the gene-environment interactions that predispose to cryptorchidism, in view of multiple small effect genetic susceptibility loci, ubiquitous exposure to mixtures of EDCs, and possible epigenetic effects. The present review provides an update of potential genetic and environmental risk factors for cryptorchidism, and future work required to better understand the etiology of this common and complex disease.

Long-Term Follow-Up after Treatment of Cryptorchidism

When considering long-term prognosis and results in adult age following treatment of cryptorchidism in childhood there are three main issues to be discussed: cosmetics, fertility, and malignancy. In the present review, the most recent research on the topics related to summaries of well-known knowledge on the field is presented.To some extent a smaller testis in a higher scrotal position than normal must be accepted as a fair cosmetic result after orchidopexy in childhood. The smaller testis size is related to the impaired fertility potential of the testis. In cases with atrophy, testicular prosthesis implantation is an option with good operative results. The risk of impaired fertility potential in adults treated in childhood for cryptorchidism is still significant and worst in bilateral disease. We need repetitive solid long-term follow-up data to show that orchidopexy performed within first year of life has markedly improved the fertility potential. Men previously having orchidopexy for cryptorchidism related to intra-abdominal testes, abnormal external genitalia and/or abnormal karyotype, and/or hypospadias are of special increased risk of developing testicular cancer. In these cases intratubular germ cell neoplasia may be diagnosed in prepubertal age. Early orchidopexy may lower the risk of developing testicular cancer.

The outcome of antenatal ultrasound diagnosed anomalies of the kidney and urinary tract in a large Danish birth cohort

OBJECTIVE

Antenatal ultrasound diagnosed anomalies of the kidney and urinary tract (AUDAKUT) are reported in 0.3%-5% on prenatal ultrasound (US) and 0.3%-4.5% on postnatal US. The anterior-posterior diameter of the renal pelvis (APD) is an essential measurement. Series with low threshold values of APD prenatally and postnatally will include healthy infants. It is important to avoid follow-up of such infants.

INTERVENTIONS

In 2006, new Danish guidelines for AUDAKUT were introduced.

AIM OF STUDY

Investigations of incidences and type of AUDAKUT based on Danish guidelines, including long-term follow-up.

DESIGN

Cohort study.

SETTING

Copenhagen University Hospital Hvidovre and Copenhagen University Hospital Rigshospitalet, Denmark.

PATIENTS

Consecutive cases with AUDAKUT in the second and third trimesters, which were either terminated before 22 completed weeks of gestation or born in the 8-year period January 2006-December 2013. Patients were followed until June 2014.

RESULTS

50 193 live born children and 24 terminated fetuses (0.05%) were included. The prevalence of AUDAKUT was only 0.39% prenatally, 0.29% at first postnatal US and 0.22% at the end of follow-up, including terminated cases. The greater the prenatal and postnatal APD, the higher risk of febrile urinary tract infection (fUTI) and surgical intervention, and lower probability of resolution. 25% of the identified patients had fUTI and/or surgery.

CONCLUSIONS

We recommend threshold values of APD at least 10 mm in the third trimester and in general at least 12 mm at first postnatal US for intensive follow-up. In this largest to date unselected birth cohort of AUDAKUT, the incidences of clinically significant AUDAKUT were in the lowest range of those previously published.

The undescended testis: Clinical management and scientific advances

Undescended testes (UDT), where one or both testes fail to migrate to the base of the scrotum, can be congenital (2-5% of newborn males) or acquired (1-2% of males). The testis may be found in any position along its usual line of descent. Cryptorchidism affects the developing testicular germ cells and increases the risk of infertility and malignancy. Clinical management aims to preserve spermatogenesis and prevent the increased risk of seminoma. Examination to document the testicular position will guide the need for imaging, medical management and the surgical approach to orchidopexy.

The Sertoli cell hormones inhibin-B and anti Müllerian hormone have different patterns of secretion in prepubertal cryptorchid boys

OBJECTIVES AND HYPOTHESES

The Sertoli-cells produce inhibin-B and Anti-Müllerian-Hormone (AMH). Much is still unknown about these hormones in prepubertal cryptorchids. The Sertoli-cells are mandatory for germ cell development. The aim of the study was to investigate if there are differences in secretion pattern of Sertoli-cell hormones and their gonadotropin feed-back mechanisms.

METHODS

Included were 94 prepubertal cryptorchid boys 0.5-13.1years with measurements of serum-inhibin-B, Anti-Müllerian-Hormone (AMH), Luteinizing Hormone (LH) and Follicle Stimulation Hormone (FSH). The serum values were measured using commercially available kits. The hormonal values were related to age-matched normal values. Testicular biopsy was taken at orchiopexy.

RESULTS

Inhibin-B positively correlated to AMH for 1-13year-old patients (p<0.0001), but not for 0.5-1year-old patients (p=0.439). For 0.5-1year-old patients inhibin-B-values tended to decrease (p=0.055), in contrast to AMH-values (p=0.852). LH was elevated more often than FSH (p=0.014). FSH and LH were positively associated in patients both 0.5-1year (p=0.042) and 1-13years of age (p<0.0001). LH correlated positively to inhibin- B (p=0.001). In contrast, FSH did not correlate to inhibin-B or AMH (p=0.755 and p=0.528). The number of A-dark spermatogonia per tubular transverse section was positively correlated to inhibin-B serum level.

CONCLUSION

Our new finding of an association between LH and inhibin-B in infancy of cryptorchid boys may be essential for the transformation of gonocytes to A-dark spermatogonia. Previously, LH associated to inhibin-B was described in early puberty only. During the first year of life inhibin-B values decreased faster than AMH. The AMH-levels may just reflect the increased Sertoli cell number that occurs during the first 3months of life.

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.

Genetic and environmental origins of hypospadias

PURPOSE OF REVIEW

The purpose of this study was to review and comment on recent original presentations dealing with genetic and environmental factors in the cause of hypospadias.

RECENT FINDINGS

The heritability is definitely high and having an affected family member is the highest identified risk factor so far. Many candidate genes and polymorphisms have been suggested for hypospadias. Some associations with hypospadias were found, and many of these were replicated inconsistently as would be expected in a complex disorder affected by both genes and environment. The consistent association of hypospadias with low birth weight, maternal hypertension, and preeclampsia suggests that placental insufficiency is a major risk factor. Maternal exposure to chemical pollutants or endocrine disruptors in high concentrations related to selected occupations or geographic areas may be additional risk factors for hypospadias, especially in genetically predisposed individuals. So far, however, no environmental chemical pollutants or endocrine disruptor with a general common impact on the risk for hypospadias in most societies has been demonstrated.

SUMMARY

A major point that should be considered regarding the action of environmental toxicants in inducing hypospadias is the cumulative effects of multiple low-dose exposures. Furthermore, interactions between genetic and environmental factors may help to explain nonreplication in genetic studies of hypospadias.

Germ cell development in the postnatal testis: the key to prevent malignancy in cryptorchidism?

To permit normal postnatal germ cell development, the mammalian testis undergoes a complex, multi-staged process of descent to the scrotum. Failure of any part of this process leads to congenital cryptorchidism, wherein the malpositioned testis finds itself at the wrong temperature after birth, which leads to secondary germ cell loss and later infertility and risk of cancer. Recent studies suggest that neonatal gonocytes transform into the putative spermatogenic stem cells between 3 and 9 months, and this initial postnatal step is deranged in cryptorchid testes. In addition, it is thought the abnormality high temperature may also impair apoptosis of remaining gonocytes, allowing some to persist to become the possible source of carcinoma in situ and malignancy after puberty. The biology of postnatal germ cell development is of intense interest, as it is likely to be the key to the optimal timing for orchidopexy.

Experience with the NICE guidelines for imaging studies in children with first pyelonephritis

PURPOSE

This retrospective study evaluates the applicability of a selective approach for imaging in children aged 0-15 years with a first episode of pyelonephritis, based on the UTI guidelines of the National Institute for Health and Clinical Excellence (NICE).

MATERIAL AND METHODS

A total of 96 consecutive patients were included (age range: 0.1-14.9 years, median age: 0.7 years), treated for a first episode of confirmed culture-positive pyelonephritis. At initial hospitalization all patients underwent ultrasound examination of the kidneys and urinary tract (US) and technetium-99m mercaptoacetyltriglycine scinti- and renography ( (99m)Tc MAG3). If vesicoureteral reflux (VUR) was suspected, then prophylactic antimicrobial therapy was prescribed and the patients were referred to a surgeon for further evaluation including voiding cystoureterography (VCU). Patients with known urological anomalies including antenatally diagnosed anomalies were excluded. All patients were followed up for a median of 5.2 years (3.5-8.6 years).

RESULTS

Initially, US findings were abnormal in 29 (30%) patients and (99m)Tc MAG3 findings were abnormal in 20 (21%) cases. At follow-up, prophylactic antimicrobial therapy was prescribed for 19 (20%), and VUR was diagnosed by VCU in 9 patients. Surgery was carried out in 7 (7%) patients, primarily for VUR. If the NICE guidelines had been initially followed, 5 of our 9 patients with VUR would not have been identified. VUR surgery was performed in 4 of these cases. Moreover, 9 cases with urological anomalies subsequently prescribed prophylactic antimicrobial therapy would have been missed.

CONCLUSION

We do not recommend following the imaging strategies of the NICE guidelines for children with a first episode of pyelonephritis. Our most important argument is that at follow-up, after a minimum of 3.5 years, the initial diagnosis of VUR would have been missed in 4 out of the 5 patients who underwent VUR surgery.

The challenge of early surgery for cryptorchidism

OBJECTIVE

In congenital cryptorchidism, a recent Nordic Consensus report recommends surgical correction at 6-12 months of age to prevent male infertility. In published series of orchiopexies the median age at surgery is often 3 years or more. The aim of this study was to evaluate whether early surgery is technically safe.

MATERIAL AND METHODS

The study included 356 boys with 418 orchiopexies and median 1 year of follow-up.

RESULTS

At follow-up 367 testes were in the scrotum without iatrogenic atrophy. Eight testes were atrophied and in 43 cases a redo operation was performed to achieve a scrotal position of the testis. All acquired undescended testes had a successful result. The age at operation for the group with congenital undescended testes in the intracanalicular position or in a position close to the external inguinal annulus was 4 months to 14.5 years. In the latter group the median age at operation for the 41 failures was 2 years and 4 months, which is significantly younger than the median age for the more successful operations (3 years and 9 months).

CONCLUSION

The standard orchiopexy is technically demanding in small boys. Focus on successful operative results in specialist centres is important when treating cryptorchidism with early surgery, otherwise the positive beneficial biological impact on fertility potential may be lost due to treatment failure.