The epidemiology of congenital cryptorchidism, testicular ascent and orchiopexy

Testicular dysgenesis syndrome: foetal origin of adult reproductive problems

The evidence for the existence of testicular dysgenesis syndrome (TDS) is presented in this review. Several epidemiological studies have shown that conditions like cryptorchidism, impaired spermatogenesis, hypospadias and testicular cancer can be associated as risk factors for each other. Thus, the risk of testis cancer is significantly increased in men with cryptorchidism and/or infertility. Several recent studies point towards early dysgenesis of the foetal testis as the biological link between these disorders. Dysgenesis has been demonstrated in biopsies of the contralateral testis of men with testis cancer and in infertile men. The histological evidence includes immature seminiferous tubules with undifferentiated Sertoli cells, microliths and Sertoli-cell only tubules. Dysgenetic testes often have an irregular ultrasound pattern, where microliths may also be visible. Our current hypothesis is that maternal exposure to endocrine disrupting chemicals may contribute to the pathogenesis of TDS. Animal experiments have shown that all TDS symptoms, except testicular cancer, can be induced by foetal exposure to anti-androgenic chemicals. However, the cause of TDS in humans remains to be determined.

Aspects cliniques, biologiques et thérapeutiques de la cryptorchidie diagnostiquée à l’âge adulte: analyse d’une série de 69 cas

But

Rapporter les aspects cliniques, biologiques et thérapeutiques de la cryptorchidie chez l’adulte et discuter de l’intérêt de l’abaissement du testicule non descendu (TND) chez l’adulte.

Patients et méthodes

Il s’agit d’une étude rétrospective colligeant 69 patients âgés de plus de 18 ans pris en charge au service d’urologie-andrologie du CHU Aristide-Le-Dantec pour cryptorchidie entre janvier 1999 et décembre 2007.

Résultats

L’âge moyen de nos patients était de 31,04 ± 8,4 ans (extrêmes 18 et 55 ans). Les principales circonstances de découverte ont été l’infertilité masculine (38 cas), la vacuité des bourses (21 cas) et la dégénérescence maligne du TND (six cas). La cryptorchidie était unilatérale dans 69,5 % et bilatérale dans 30,4 % des cas. Le spermogramme effectué chez 60 de nos patients a montré une azoospermie dans 46,6 % des cas, une oligozoospermie dans 38,3 % et une numération de spermatozoïdes normale dans 15 % des cas. Tous les patients ayant une cryptorchidie bilatérale avaient une azoospermie. À l’exploration chirurgicale, le TND a été retrouvé dans 95,6 % des cas (66 patients). Le principal type de traitement réalisé a été l’abaissement testiculaire. L’histologie des pièces d’orchidectomie sur testicule non tumoral (n = 7) a trouvé dans tous les cas une atrophie testiculaire sévère avec absence complète de cellules germinales. Les types histologiques des cancers étaient le séminome (n = 3) et le carcinome embryonnaire (n = 3). Parmi les patients ayant une azoospermie (n = 28), aucun cas d’induction de la spermatogenèse après abaissement testiculaire n’a été observé. Parmi les patients ayant consulté pour infertilité masculine, trois d’entre eux ont eu des enfants après abaissement testiculaire, soit un taux de paternité de 7,8 %.

Conclusion

Dans la cryptorchidie de l’adulte, l’abaissement du testicule a peu d’impact sur la fertilité masculine. Mais, vu les progrès actuels de l’assistance médicale à la procréation (AMP), le dogme d’orchidectomie systématique devant un TND diagnostiqué à l’âge adulte doit être reconsidéré.

Acquired cryptorchidism is frequent in infancy and childhood

Accurate prevalence data for acquired cryptorchidism are currently sparse and systematic prospective studies have not yet been reported. Our aim was to determine the prevalence of testicular ascent in childhood. In a prospective longitudinal population-based child cohort from Copenhagen, Denmark (1997-2007), testicular position was examined according to a standardised protocol in a total of 1072 boys, at birth (n = 1051), at 3 months (n = 983), 18 months (n = 888), 36 months (n = 790) and again once between 4 1/2 and 10 years of age (n = 509). Ascensus testis was defined as ascent of the testis into a cryptorchid position after normal scrotal position at birth. A congenital cryptorchid testis with spontaneous postnatal descent followed by recurrence of cryptorchidism was named recurrent cryptorchidism. Ascensus testis occurred in 0.2%, 0.6% and 0.6% of boys at 3, 18 and 36 months of age respectively. When including recurrent cryptorchidism the prevalence was 0.2%, 1.2% and 0.8% respectively. Ascensus testis accounts for 58% of all cases of cryptorchidism (congenital and acquired) at 18 months, 71% at 36 months and thereafter 69%. Ascensus testis accounts for more than half of cryptorchid testes seen in childhood and occurs in both previously scrotal and cryptorchid testes. We therefore recommend that all boys should have testis position checked regularly during childhood, at least up to 3 years of age.

Maternal pregnancy levels of polychlorinated biphenyls and risk of hypospadias and cryptorchidism in male offspring

BACKGROUND

The etiologies of the male urogenital anomalies cryptorchidism and hypospadias are poorly understood. It has been suggested, however, that in utero hormone levels may be related to risk. Endocrine-disrupting chemicals, including polychlorinated biphenyl (PCB) compounds, may alter hormone levels and thereby affect the fetus.

OBJECTIVES

To examine whether in utero PCB exposure is related to cryptorchidism and hypospadias, we examined PCB levels among pregnant women enrolled in the Collaborative Perinatal Project (CPP).

METHODS

The CPP enrolled pregnant women at 12 U.S. medical centers between 1959 and 1965. For the present research, we analyzed third-trimester serum samples from the mothers of 230 sons with cryptorchidism, 201 sons with hypospadias, and 593 sons with neither condition. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression and examined the associations of each anomaly with individual PCB congener levels, sum of PCBs, and several functional groupings of PCBs.

RESULTS

In general, the ORs for cryptorchidism or hypospadias showed no notable associations with individual PCB congener levels or functional groupings of PCBs. However, the ORs and 95% CIs for the sum of PCBs associated with hypospadias were as follows: 0-1.9 microg/L, reference group; 2-2.9 microg/L, OR = 1.57, 95% CI, 1.05-2.34; 3-3.9 microg/L, OR = 1.45, 95% CI, 0.90-2.34; and > or = 4.0 microg/L, OR = 1.69, 95% CI, 1.06-2.68; p-value for trend = 0.08.

CONCLUSIONS

Given the large number of associations examined, these findings do not strongly support the hypothesis that PCBs are associated with cryptorchidism or hypospadias. Because population serum PCB levels at the time of sample collection were considerably higher than levels at present, it is unlikely that current PCB exposure is related to the development of either anomaly.

Sterile testis complementation with spermatogonial lines restores fertility to DAZL-deficient rats and maximizes donor germline transmission

Despite remarkable advances in assisted reproductive capabilities approximately 4% of all couples remain involuntarily infertile. In almost half of these cases, a lack of conception can in some measure be attributed to the male partner, wherein de novo Y-chromosomal deletions of sperm-specific Deleted-in-Azoospermia (DAZ) genes are particularly prevalent. In the current study, long-term cultures of rat spermatogonial stem cells were evaluated after cryo-storage for their potential to restore fertility to rats deficient in the DAZ-like (DAZL) gene. Detailed histological analysis of DAZL-deficient rat testes revealed an apparently intact spermatogonial stem cell compartment, but clear failure to produce mature haploid gametes resulting in infertility. After proliferating >1 million-fold in cell number during culture post-thaw, as few as 50,000 donor spermatogonia transplanted into only a single testis/recipient effectively restored fecundity to DAZL-deficient rats, yielding 100% germline transmission to progeny by natural mating. Based on these results, the potency and efficacy of this donor stem cell line for restoring fertility to azoospermic rodents is currently unprecedented. Prospectively, similar successes in humans could be directly linked to the feasibility of obtaining enough fully functional spermatogonial stem cells from minimal testis biopsies to be therapeutically effective. Thus, regeneration of sperm production in this sterile recipient provides an advanced pre-clinical model for optimizing the efficacy of stem cell therapies to cure a paradoxically increasing number of azoospermic men. This includes males that are rendered infertile by cancer therapies, specific types of endocrine or developmental defects, and germline-specific de novo mutations; all of whom may harbor healthy sources of their own spermatogonial stem cells for treatment.

Endocrine-disrupting chemicals: an Endocrine Society scientific statement

There is growing interest in the possible health threat posed by endocrine-disrupting chemicals (EDCs), which are substances in our environment, food, and consumer products that interfere with hormone biosynthesis, metabolism, or action resulting in a deviation from normal homeostatic control or reproduction. In this first Scientific Statement of The Endocrine Society, we present the evidence that endocrine disruptors have effects on male and female reproduction, breast development and cancer, prostate cancer, neuroendocrinology, thyroid, metabolism and obesity, and cardiovascular endocrinology. Results from animal models, human clinical observations, and epidemiological studies converge to implicate EDCs as a significant concern to public health. The mechanisms of EDCs involve divergent pathways including (but not limited to) estrogenic, antiandrogenic, thyroid, peroxisome proliferator-activated receptor gamma, retinoid, and actions through other nuclear receptors; steroidogenic enzymes; neurotransmitter receptors and systems; and many other pathways that are highly conserved in wildlife and humans, and which can be modeled in laboratory in vitro and in vivo models. Furthermore, EDCs represent a broad class of molecules such as organochlorinated pesticides and industrial chemicals, plastics and plasticizers, fuels, and many other chemicals that are present in the environment or are in widespread use. We make a number of recommendations to increase understanding of effects of EDCs, including enhancing increased basic and clinical research, invoking the precautionary principle, and advocating involvement of individual and scientific society stakeholders in communicating and implementing changes in public policy and awareness.

Undescended testis in older boys: further evidence that ascending testes are common

INTRODUCTION

We recommend orchiopexy between 9 and 18 months of age for surgical, testicular, and psychological reasons. However, in practice, we observed many patients coming to orchiopexy at a later age. To understand this difference better, we reviewed our experience with patients undergoing late orchiopexy.

METHODS

We reviewed retrospectively the office medical records of all boys who had undergone an orchiopexy between July 1997 and April 2006. We defined a "late" orchiopexy as that performed at 4 years of age or later. Each boy was examined carefully by a pediatric urologist, and preoperative, intraoperative, and postoperative findings were reviewed.

RESULTS

There were 191 late orchiopexies in 177 patients (from a total of 587 orchiopexies in 552 patients). Median age at the operation was 7.2 years (range, 4.0-16.2). Preoperatively, the testes were palpable in 140 (72%) and nonpalpable in 51 (28%). The apparent reason for the late orchiopexy was an ascending testis (previously descended) in 85 (45%), parental delay in 41 (22%), late referral in 39 (20%), and iatrogenic cryptorchidism in 18 (9%). Ascended testes were more likely to have a history of being retractile (85% vs 30%), to have a patent processus vaginalis (78% vs 54%), and to be localized to the superficial inguinal area (87% vs 50%).

CONCLUSIONS

Primary care provider and parent education on the benefits of early orchiopexy is important, but in addition, ascending testes are much more common than previously thought. Patients with retractile testes should be followed regularly.

Undescended testis: current theories of etiology

PURPOSE OF REVIEW

Nonsyndromic cryptorchidism or undescended testis is a structural defect of infants and children whose etiology is unknown but likely related to a combination of genetic susceptibility and environmental factors. This review will focus on factors that may contribute to the etiology of this common and complex disease.

RECENT FINDINGS

The incidence of cryptorchidism is estimated to be 2-4% or higher in some populations. Data suggesting increasing prevalence are conflicting, possibly related to problems with diagnostic accuracy. Increased risk of cryptorchidism in first-degree relatives suggests a significant genetic contribution to susceptibility. Sequence variants within key candidate genes, such as insulin-like 3 and relaxin/insulin-like family peptide receptor 2, in cases of nonsyndromic cryptorchidism are infrequent and of unclear significance. Epidemiological data suggest that fetal growth restriction, maternal factors such as smoking, alcohol use and gestational diabetes, and exposure to environmental chemicals may contribute to risk, although data are inconsistent.

SUMMARY

The available evidence suggests a significant genetic contribution to cryptorchidism susceptibility that may be modulated by environmental risk factors. Additional studies are needed to define these factors, their complex interaction and their effects on testicular development and descent.

Role of hormones, genes, and environment in human cryptorchidism

Cryptorchidism is the most frequent congenital birth defect in male children (2-4% in full-term male births), and it has the potential to impact the health of the human male. In fact, although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. Furthermore, some reports have highlighted a significant increase in the prevalence of cryptorchidism over the last few decades. Etiology of cryptorchidism remains for the most part unknown, and cryptorchidism itself might be considered a complex disease. Major regulators of testicular descent from intraabdominal location into the bottom of the scrotum are the Leydig-cell-derived hormones testosterone and insulin-like factor 3. Research on possible genetic causes of cryptorchidism has increased recently. Abundant animal evidence supports a genetic cause, whereas the genetic contribution to human cryptorchidism is being elucidated only recently. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene have been recognized as causes of cryptorchidism in some cases, but some chromosomal alterations, above all the Klinefelter syndrome, are also frequently involved. Environmental factors acting as endocrine disruptors of testicular descent might also contribute to the etiology of cryptorchidism and its increased incidence in recent years. Furthermore, polymorphisms in different genes have recently been investigated as contributing risk factors for cryptorchidism, alone or by influencing susceptibility to endocrine disruptors. Obviously, the interaction of environmental and genetic factors is fundamental, and many aspects have been clarified only recently.

Anti-Müllerian hormone in men with normal and reduced sperm concentration and men with maldescended testes

OBJECTIVE

To evaluate serum anti-Müllerian hormone (AMH) in well-characterized men with normal and reduced sperm concentration and in men with a history of or persistent maldescended testes as a possible clinical marker of male factor infertility and/or maldescended testes.

DESIGN

Retrospective analysis of 199 men selected from our database (Androbase).

SETTING

The university-based Institute of Reproductive Medicine.

PATIENT(S)

One hundred eight men with normal and 60 men with reduced sperm concentration without known cause of infertility and additionally 31 infertile men with current or former maldescended testes were evaluated.

INTERVENTION(S)

Serum AMH was analyzed by an in-house ELISA.

MAIN OUTCOME MEASURE(S)

Hormone and semen parameters were compared and correlated with AMH.

RESULT(S)

No significant differences were found in AMH levels. Only in men with maldescended testes did AMH correlate negatively with FSH and positively with testicular volume and sperm concentration. No correlations between AMH and LH or testosterone (T) were found.

CONCLUSION(S)

Anti-Müllerian hormone serum levels are not significantly affected by impaired spermatogenesis in general but are correlated with spermatogenic parameters in men with current or former maldescended testes. Therefore, AMH measurement does not improve clinical routine diagnostics but should be evaluated further in patients with maldescended testes. Anti-Müllerian hormone might serve as a marker of Sertoli cell number, function, and/or maturation in these men.

Early orchiopexy improves subsequent testicular development and spermatogenesis in the experimental cryptorchid rat model

PURPOSE

The most appropriate period for orchiopexy is controversial. We performed histological analyses of undescended testes to evaluate the influence of orchiopexy timing in an experimental cryptorchid rat model. Furthermore, we extrapolated the timing of orchiopexy in humans from our results.

MATERIALS AND METHODS

Experimental cryptorchid rats were induced with androgen blocker by injecting flutamide into the abdomen of pregnant Sprague-Dawley rats (Chubu Kagaku Shizai, Nagoya, Japan) for 7 days from days 14 to 20 of gestation. Approximately 90% of male newborns had undescended testes and we performed orchiopexy on them 4, 5 and 7 weeks after birth. The testes were removed 10 weeks after birth in all groups, and weight and histological findings were assessed. A modified Johnsen score was used to determine spermatogenesis maturity and germ cell apoptosis was also evaluated.

RESULTS

Nonoperated undescended testes showed atrophic and hypospermatogenesis with germ cell apoptosis, whereas treated undescended testes showed the development of early elongated spermatids. In addition, performing orchiopexy 4 weeks after birth decreased the degeneration of undescended testes compared with that in other groups.

CONCLUSIONS

From the point of view of only testicular development 4-week-old rats reportedly correspond to 1-year-old humans. While we should be cautious when extrapolating our findings to the clinical setting, our current study provides evidence in support of early orchiopexy during the first year of life.

Hormonal and genetic control of testicular descent

Cryptorchidism has the potential to affect the health of the human male. Although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. The aetiology of cryptorchidism remains, for the most part, unknown and cryptorchidism itself might be considered a complex disease. This reflects the intricate mechanisms regulating testicular development and descent from intra-abdominal location into the bottom of the scrotum, involving different anatomical and hormonal factors. Major actors of testicular descent are the Leydig cell-derived hormones testosterone and insulin-like factor 3, even if other factors may play a role. Although considerable evidence exists in animals to support a genetic cause, the genetic contribution to human cryptorchidism is only recently being elucidated. Environmental factors might also contribute to the aetiology of cryptorchidism and its increased incidence in recent years. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene explain a minority of cases of cryptorchidism, but research on genetic polymorphisms that may also influence susceptibility to endocrine disruptors is shedding light on this field.

The true incidence of cryptorchidism in Denmark

PURPOSE

Considerable controversy exists regarding the recently published high prevalence of cryptorchidism and the actual orchiopexy rate in Denmark. Therefore, we carried out another prevalence study.

MATERIALS AND METHODS

The study population included 1,094 consecutive males delivered alive at Glostrup University Hospital during 2002, with a 4-year review of patient data and telephone contact with primary physicians.

RESULTS

At birth the overall frequency of cryptorchidism was 2.4% (26 of 1,088 cases, 23% bilateral). The frequency of cryptorchidism in singletons was 2.4% (24 of 1,012 patients). The frequency of cryptorchidism in patients with a birth weight of 2,500 gm or more was 2.1%, compared to 8.2% in those with a birth weight of less than 2,500 gm (chi-square p <0.05). The frequency of cryptorchidism in twins was 2.6% (2 of 76). The frequency of birth weight below 2,500 gm was 51% (39 of 76) in twins and 4.9% (50 of 1,012) in singletons (chi-square p <0.00005). The weight of the placenta was higher in twins (median 1,000 gm) than in singletons (650 gm). At age 4 years 1.6% of the boys had undergone or were waiting to undergo surgery for cryptorchidism, and 0.6% had a diagnosis of retractile testes.

CONCLUSIONS

In a small cohort of newborns the incidence of cryptorchidism in Denmark has not changed, and is similar to previous reports from the 1950s. The risk is higher in low birth weight singleton neonates but does not appear to be higher in twins, despite lower birth weight and prematurity.

Maternal pregnancy serum level of heptachlor epoxide, hexachlorobenzene, and beta-hexachlorocyclohexane and risk of cryptorchidism in offspring

Prenatal exposure to environmental endocrine disrupters has been postulated to cause adverse effects on male reproductive health. Exposure to organochlorine pesticides with anti-androgenic and estrogenic potency has been shown to interfere with the sex-hormone-dependent process of testicular descent in animal models. We examined the relation between serum levels of the pesticides heptachlor epoxide (HCE), hexachlorobenzene (HCB), and beta-hexachlorocyclohexane (beta-HCCH) in pregnant women, and the occurrence of cryptorchidism in their sons. These three pesticides were previously suggested as risk factors for cryptorchidism. In a nested case-control design, we compared serum levels between mothers of cases (n = 219) and controls (n = 564), selected from the Collaborative Perinatal Project, a US birth cohort study of pregnancies in 1959-1966. The offspring of mothers with HCE levels above the 90th percentile compared to those below the 10th percentile had an adjusted odds ratio of cryptorchidism of 1.2 (95% confidence interval 0.6-2.6); for beta-HCCH the odds ratio was 1.6 (0.7-3.6). For HCB the adjusted odds ratio was near one. These results provide little support for an association of cryptorchidism with exposure to low levels of HCE or HCB. For beta-HCCH the findings were somewhat suggestive of an association but were inconclusive.

Incidence of Testicular Ascent in Boys With Retractile Testes

PURPOSE

The incidence of testicular ascent of a previously descended but retractile testis is reported to be between 2% and 45%. It has been our bias that only a small percent of retractile testes ascend and ultimately require orchiopexy.

MATERIALS AND METHODS

We performed a retrospective review of all retractile testes diagnosed by any of 4 pediatric urologists at our institution from 1996 to 2005. A retractile testis was defined as one that could be brought to at least the mid scrotum without tension despite a history of maldescent or a retractile nature. Patients were excluded if followup was less than 6 months or they had a history of ipsilateral inguinal surgery. A followup telephone survey was done in patients not reexamined at resolution.

RESULTS

A total of 172 patients met our inclusion criteria and were followed to resolution. A total of 274 retractile testes were initially identified, including 26% unilateral and 74% bilateral testes. A total of 19 testes ascended and ultimately required orchiopexy within a followup of 6 to 101 months. A patent processus vaginalis was identified in 13 cases (68%). Another 235 patients initially seen with a diagnosis of retractile testis who had no followup examination at our institution were contacted via telephone. This set of boys initially had a total of 392 involved testes, of which 2 underwent orchiopexy elsewhere before resolution. The incidence of secondary ascent was 3.2% in the combined set of patients.

CONCLUSIONS

Retractile testes can ascend and, therefore, they require followup until resolution. In our experience most retractile testes do not require surgery.

Cryptorchidism: the veracity of online information accessible to the public

PURPOSE

The objective of this study is to assess the quality of information regarding cryptorchidism using common Internet resources.

METHODS

Five common search engines were queried with the string "cryptorchidism OR undescended testicle OR undescended testes OR retractile testes OR retractile testicle." The first 30 sites retrieved via each engine were reviewed, and the content veracity of the following components was assessed independently by 2 pediatric urologists: natural history, diagnosis, treatment, complications, and long-term outcome. Components were scored 0 to 2 based on whether topics were addressed and in accordance with accepted practice patterns.

RESULTS

Of the 124 of 150 links accessible, 84% were oriented toward laypeople. Only 43 (35%) had endorsement by a nonprofit accreditation organization, but 76 (61%) had affiliation with a medical institution/professional. Authors were mostly pediatric urologists/surgeons (36%) or unspecified (48%). Median total scores were only 16 of 44 primarily because of incomplete information rather than misinformation. High scoring components included natural history, surgical options, long-term outcomes for fertility, and malignancy. Components scoring poorly included future sexuality, imaging, hormonal use, and treatment complications. Multivariate analysis demonstrated that only accreditation status was associated with high quality (P = .05).

CONCLUSIONS

Online information, when available to the public, is generally of good quality. However, many Web sites fail to adequately address all aspects of the condition.

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.

Reduction in the number of orchidopexies for cryptorchidism after recognition of acquired undescended testis and implementation of expectative policy

BACKGROUND

Since the mid-1990s, acquired undescended testis has gradually been recognised as a separate entity for which the efficacy of prepubertal surgery has not been univocally been demonstrated. Therefore, in our hospital, orchidopexy was no longer routinely performed for acquired undescended testis.

AIM

To investigate the effect of expectative policy in our hospital on the number of orchidopexies.

METHODS

Two 5-year periods were compared. Period A (1991-1995), in which undescended testis was treated surgically, and period B (2000-2004), in which prepubertal orchidopexy in our hospital was no longer performed for acquired undescended testis. In addition, a comparison was made between the percentage reduction in hospital and national figures.

RESULTS

In period B, the number of orchidopexies in our hospital was reduced by 61.8% (from 387 to 148), mainly in the age group >6 years. Nationally, during the same period, the number of orchidopexies decreased only by 2.4% (from 18 024 to 17 591).

CONCLUSION

The results of this study confirm that recognition of acquired undescended testis is crucial for reducing the high number of (late) orchidopexies.

Surgical treatment of undescended testes

The mainstay of therapy for undescended testes is operative treatment within the first years of life in order to avoid ongoing testicular degenerative changes. The surgical therapy for the palpable undescended testis is orchiopexy and when the testis is non-palpable, a supplementary laparoscopic approach. Success of orchiopexy for inguinal testes has been >95% and for abdominal testes >85-90% in most series.

CONCLUSION

Operation within the first year of life is a safe therapy for undescended testes.

Cryptorchidism in common eutherian mammals

Cryptorchidism is failure of one or both testes to descend into the scrotum. Primary fault lies in the testis. We provide a unifying cross-species interpretation of testis descent and urge the use of precise terminology. After differentiation, a testis is relocated to the scrotum in three sequential phases: abdominal translocation, holding a testis near the internal inguinal ring as the abdominal cavity expands away, along with slight downward migration; transinguinal migration, moving a cauda epididymidis and testis through the abdominal wall; and inguinoscrotal migration, moving a s.c. cauda epididymidis and testis to the bottom of the scrotum. The gubernaculum enlarges under stimulation of insulin-like peptide 3, to anchor the testis in place during gradual abdominal translocation. Concurrently, testosterone masculinizes the genitofemoral nerve. Cylindrical downward growth of the peritoneal lining into the gubernaculum forms the vaginal process, cremaster muscle(s) develop within the gubernaculum, and the cranial suspensory ligament regresses (testosterone not obligatory for latter). Transinguinal migration of a testis is rapid, apparently mediated by intra-abdominal pressure. Testosterone is not obligatory for correct inguinoscrotal migration of testes. However, normally testosterone stimulates growth of the vaginal process, secretion of calcitonin gene-related peptide by the genitofemoral nerve to provide directional guidance to the gubernaculum, and then regression of the gubernaculum and constriction of the inguinal canal. Cryptorchidism is more common in companion animals, pigs, or humans (2–12%) than in cattle or sheep (≤1%). Laboratory animals rarely are cryptorchid. In respect to non-scrotal locations, abdominal testes predominate in cats, dogs, and horses. Inguinal testes predominate in rabbits, are common in horses, and occasionally are found in cats and dogs. S.c. testes are found in cattle, cats and dogs, but are most common in humans.

The nomad testis

Perspective on the paper by Hack et al(see page 17)

Prevalence of acquired undescended testis in 6-year, 9-year and 13-year-old Dutch schoolboys

OBJECTIVE

To investigate the prevalence of acquired undescended testis (UDT) in Dutch schoolboys.

DESIGN AND PARTICIPANTS

As a part of routine school medical examinations, during a 2-year period (2001-3), testis position was determined in 6-year, 9-year and 13-year-old schoolboys. Before the examination, a parent questionnaire was sent inquiring both about the position of the testes and whether the child had been admitted earlier to hospital for orchidopexy. In 6-year and 13-year olds, a physical examination was performed by the school medical officer; in 9-year olds, a school nurse interview was held. Each boy for whom there was any doubt of the scrotal position was referred to the hospital for examination of both testes.

SETTING

Institution for Youth Health Care "Noordkennemerland" and Medical Centre Alkmaar, Alkmaar, the Netherlands.

RESULTS

Testis position was determined in 2042 boys aged 6, 1038 aged 9 and 353 aged 13. Of these, 47, 53 and 8 boys, respectively, were referred to the hospital and seen for further evaluation. The diagnosis of acquired UDT was made in 25 boys aged 6, 23 aged 9 and four aged 13. In 33 boys, a congenital UDT was diagnosed; 32 (97%) had already been diagnosed and treated at an early age.

CONCLUSIONS

The prevalence of acquired UDT for 6-year, 9-year and 13-year olds was, respectively, 1.2% (25/2042), 2.2% (23/1038) and 1.1% (4/353). In addition, congenital UDT is treated during the early years of life and, in contrast with popular belief, screening programmes for detecting UDT in the early years are successful.

Puberty stage and spontaneous descent of acquired undescended testis: implications for therapy?

We assessed spontaneous descent of acquired undescended testis (UDT) at puberty. 299 Boys (aged 1.2-16.5 years, mean 9.4) with 350 acquired-UDT were examined annually during a 12.6-year period (mean 3.1). An acquired-UDT was defined as a previously intrascrotal testis which can no longer be manipulated into a stable scrotal position. Each year, position of the testis and pubertal development according to Tanner's stages were assessed. Early puberty was defined as puberty stage G2 (testicular volume 4-9 mL), mid-puberty as puberty stages G3 (testicular volume 10 mL) and G4 (testicular volume 11-15 mL), and late puberty as puberty stage G5 (testicular volume >15 mL). Follow-up was completed if spontaneous descent had occurred, if mid-pubertal orchidopexy (ORP) had to be performed, if the boy was lost for follow-up, or if pre-pubertal ORP was performed in another hospital. In 139 boys with 164 acquired-UDT follow-up was meanwhile completed. Twelve boys with 14 UDT were lost for follow-up. In an additional 16 boys with 21 UDT, ORP was performed in another hospital. In 98 of the remaining 129 (76.0%) acquired-UDT spontaneous descent at puberty occurred. Mean follow-up was 2.5 years (range 0.2-8.5). In 70 of 98 testes (71.4%) descent occurred in early puberty, in 26 of 98 testes (26.5%) in mid-puberty, and in two testes in late puberty. In 31 of 129 testes (24.0%) ORP had to be performed at mid (30 cases) or late (one case) puberty. In this series, 98 of 129 acquired-UDT (76.0%) descended spontaneously at puberty, whereas in 31 of 129 (24.0%) pubertal ORP was performed. If ORP is postponed until puberty stage G3 (testicular volume of 10 mL) three of four acquired-UDT will descend spontaneously.

Retractile Testis—Is it Really a Normal Variant?

PURPOSE

Retractile testes are thought to represent a normal variant of descended testes in prepubertal boys. We studied retractile testes to determine their natural history.

MATERIALS AND METHODS

We retrospectively reviewed the charts of 122 boys (mean age 5.4 years) who were referred for a suspected undescended testis and were found to have a retractile testis. A retractile testis was defined as a suprascrotal testis that could be manipulated easily into the scrotum and remained there without traction until the cremasteric reflex was induced. The boys were followed by annual examinations, which demonstrated the presence of retractile, descended (nonretractile) or undescended testes, and the presence or absence of a taut or inelastic spermatic cord in association with a retractile testis.

RESULTS

Of 204 retractile testes 61 (30%) descended (became nonretractile), 66 (32%) became UDTs and 77 (38%) remained retractile. Of the 62 retractile testes with a taut or inelastic spermatic cord 35 (56%) became UDTs. Of the 61 orchiopexies performed 8 (13%) showed a patent processus vaginalis. Boys in whom UDTs vs descended testes developed were a mean of 4.9 vs 6.6 years old (p = 0.001). The chance of spontaneous descent was 58% in boys 7 years or older, compared to 21% in boys younger than 7 (p <0.0001).

CONCLUSIONS

A retractile testis is not a normal variant. Retractile testes have a 32% risk of becoming an ascending or acquired undescended testis. The risk is higher in boys younger than 7 years old, or when the spermatic cord seems tight or inelastic. Boys with retractile testes should be monitored annually until the testes have clearly descended.

The cryptorchidism prevalence among infants in the general population of Rotterdam, the Netherlands

Published trends and geographical differences in cryptorchidism rates are almost exclusively derived from hospital-based birth defect registers, which are sensitive to selection bias and incomplete reporting. This study aimed to accurately assess the cryptorchidism prevalence in the general population of Rotterdam. Of 7652 consecutive male live births, 7292 (95%) were examined for cryptorchidism at Child Healthcare Centres around the age of 1 month. In a subgroup of cases, the persistence of cryptorchidism was re-assessed during a follow-up examination by expert specialists. The cryptorchidism rate at the median age of 35 days was 1.2% (89/7292). In the re-examined subgroup (median age 95 days) 69% of the boys (24/35) had persistent cryptorchidism, of which 20 were unilateral and four bilateral. The population rate of 1.2% falls within the range of 0.9-9% reported by others. Differences in case ascertainment and population characteristics probably explain part of the differences between studies. Our cross-sectional design does not allow for analysis of a temporal trend, but provides a baseline for future trend studies. To study cryptorchidism rates, trends, and risk factors, a systematic case ascertainment is warranted.

The changing presentation of germ cell tumours of the testis between 1983 and 2002

OBJECTIVE

To prospectively investigate the presentation of germ cell tumours (GCTs) of the testis in terms of stage or histology, as the incidence of this disease in increasing.

PATIENTS AND METHODS

Patients diagnosed with GCT of the testis between 1983 and 2002 were categorised into three periods depending on the date of diagnosis of the GCT, and the presentational characteristics assessed. RESULTS There was a significant increase in the proportion of patients presenting with stage I disease (59% to 78%) and seminoma (43% to 58%) over this period. There was also a significant reduction in the size of the primary tumour (5 to 4 cm).

CONCLUSION

A greater proportion of patients with GCT are presenting with stage I seminoma, the reasons for which are unclear, although earlier diagnosis through improved awareness of GCT may be important.

Effect of cryptorchidism and retractile testes on male factor infertility: A multicenter, retrospective, chart review

This multicenter retrospective chart review study performed on 162 cryptorchid patients and on 34 subjects with retractile testes suggests that cryptorchidism and retractile testes can alter spermatogenesis, with more serious damage observed in bilateral cryptorchidism. This spermatogenetic impairment is probably related to the lack of an appropriate or timely surgical correction.

Germ cell development in the descended and cryptorchid testis and the effects of hormonal manipulation

Germ cell development is an active process in normal testes during the first 4 years after birth, with transformation of the neonatal gonocytes into adult dark spermatogonia and then primary spermatocytes. The hormonal regulation of these changes is not fully understood, with evidence both for and against a role for gonadotrophins and androgens. Early surgical intervention in infancy aims to prevent or reverse germ cell maldevelopment. Although hormonal treatment for maldescent has been shown to be ineffective, there is still controversy over whether it may be useful as an adjunct to surgery to stimulate germ cells. Current evidence suggests that hormonal therapy may not stimulate transformation of neonatal gonocytes but may trigger prepubertal mitosis of primary spermatocytes. Further studies are required to determine the role of hormone treatment on germ cell development.

Laparoscopic assessment and treatment of non-palpable testis in an 18-year-old male

Laparoscopy, both diagnostic and therapeutic, has been used in the management of pediatric non-palpable testes. We report a case of left non-palpable testis at the unusual age of 18 years. Laparoscopic exploration revealed an intra-abdominal testis lying between the internal inguinal ring and external iliac vessels. The testis was visually in good condition and, in contrast to the accepted procedure of orchiectomy performed in late adolescent cryptorchidism, we decided to preserve this intra-abdominal testis, which was located too far from the scrotum for a primary orchidopexy. The first stage of the Fowler-Stephens procedure was performed laparoscopically. The second-stage orchidopexy was performed successfully through an inguinal approach 3 months later, after sonographic ascertainment of non-decreased testicular volume. Laparoscopy allows thorough exploration for an intra-abdominal testis, with simultaneous therapeutic options. Our experience highlights the feasibility of laparoscopic assessment and treatment of cryptorchidism in adolescents and young adults.

Androgen receptor gene CAG and GGC repeat lengths in cryptorchidism

OBJECTIVE

Cryptorchidism is the most common congenital birth defect in male children, and accumulating evidence suggests that genetic abnormalities may be associated with it. The androgen receptor has two polymorphic sites in exon 1, with different numbers of CAG and GGC repeats, resulting in variable lengths of polyglutamine and polyglycine stretches. Longer CAG repeats result in a reduced androgen receptor transcriptional activity, but the role of the GGC triplets is less clear. In this study we analysed CAG and GGC repeat lengths in men with a history of cryptorchidism, associated or not with impairment of sperm production, in comparison with normal fertile subjects.

METHODS

We analysed CAG and GGC repeat lengths in a group of 105 ex-cryptorchid men in comparison with 115 fertile non-cryptorchid men.

RESULTS

No difference was found between patients and controls in the mean and median values, and in distribution of CAG and GGC, when considered separately. However, the analysis of the joint distribution of CAG and GGC showed that some combinations are significantly more frequent in men with bilateral cryptorchidism (who frequently presented severe testiculopathies), in a manner similar to that found in idiopathic infertile subjects.

CONCLUSIONS

Although further studies are needed to elucidate the possible role of specific CAG/GGC combinations as a causative factor, these data suggest a possible association between androgen receptor gene polymorphisms and cryptorchidism.

NEOADJUVANT GONADOTROPIN-RELEASING HORMONE THERAPY BEFORE SURGERY MAY IMPROVE THE FERTILITY INDEX IN UNDESCENDED TESTES: A PROSPECTIVE RANDOMIZED TRIAL

PURPOSE

Subfertility is considered the principal consequence of cryptorchidism even after timely orchiopexy. Gonadotropin-releasing hormone (GNRH) treatment appears to improve fertility later in life by inducing germ cell maturation. In a prospectively randomized trial we investigated whether preoperative GNRH therapy improves the fertility index in primary cryptorchidism.

MATERIALS AND METHODS

A total of 42 boys 11 to 100 months old (median 33.5) with 63 undescended testes were prospectively assigned to 2 groups during a 6-month period. Patients were randomized to receive either orchiopexy alone (21 patients) or with neoadjuvant GNRH therapy (21) as a nasal spray for 4 weeks at 1.2 mg per day. In both groups testicular biopsies were performed at the time of orchiopexy and histopathological fertility index was determined.

RESULTS

Mean fertility index in the group treated with GNRH before surgery was significantly higher (1.05, SD +/- 0.71) compared to the group without hormonal stimulation (0.52, SD +/- 0.39, p <0.05). The subgroup of neoadjuvant stimulated boys younger than 24 months achieved the best results compared to the age matched boys without hormonal treatment.

CONCLUSIONS

Neoadjuvant GNRH treatment improves fertility index in prepubertal cryptorchidism. Consequently, preoperative hormone therapy should improve fertility in adulthood. Additionally, the nasal application is well tolerated, safe and already recommended in an adjuvant setting after orchiopexy. Maximum salvage of active germinal tissue is achieved by treating cryptorchidism before the end of the first year of life.

EXPRESSION OF ESTROGEN RECEPTOR α AND PROGESTERONE RECEPTOR IN CHILDREN WITH UNDESCENDED TESTICLE PREVIOUSLY TREATED WITH HUMAN CHORIONIC GONADOTROPIN

PURPOSE

The aim of this study was to investigate expression of estrogen receptor alpha (ERalpha) and progesterone receptor (PR) in paratesticular tissues obtained from boys with undescended testes.

MATERIALS AND METHODS

A total of 65 boys with unilateral cryptorchidism and failed human chorionic gonadotropion treatment underwent orchiopexy. A small sample of gubernaculum, cremasteric muscle and processus vaginalis was obtained. A total of 57 boys who underwent inguinal hernia repair served as the control group. All boys in the control group had testes in the scrotum. The expression of estrogen receptor alpha and progesterone receptor was measured by counting the number of ERalpha or PR positive cells detected by immunohistochemical analysis.

RESULTS

ERalpha and PR density was higher in cremasteric muscle and processus vaginalis obtained from boys with undescended testes than in the control group. Density of progesterone receptor in the examined groups was lower than the density of estrogen receptor.

CONCLUSIONS

ERalpha and PR are expressed in paratesticular tissues important for normal testicular descent. ERalpha was over expressed in cremasteric muscle and processus vaginalis in boys with undescended testes previously treated with human chorionic gonadotropin.

Hypospadias in the neonate

Hypospadias is a common developmental disorder of the urogenital tract, occurring in approximately 1 in 125 live male births. Defined as an atypical urethral opening anywhere along the shaft of the penis, scrotum, or perineum, hypospadias is often associated with a deficient prepuce and chordee. Hypospadias usually occurs as an isolated defect, but can be part of a recognized syndrome or associated with other genital anomalies. The etiology of nonsyndromic hypospadias is unknown, and is believed to be multifactorial. Recent studies have implicated factors such as familial inheritance, low birth weight, assisted reproductive technology, advanced maternal age, paternal subfertility, and endocrine-disrupting chemicals in the pathogenesis of hypospadias. Infants with hypospadias should not undergo circumcision. Currently, most infants with hypospadias undergo surgical reconstruction between 4 and 8 months of age. Parents of a newborn with hypospadias may be anxious and have many questions about their infant's condition. They should be given the opportunity to speak to a pediatric urologist as early as possible. This article provides a guide to the embryologic origins of hypospadias and a photographic atlas to aid bedside clinicians in identifying the spectrum of hypospadias in the newborn.