The primary aim of this study was to examine factors associated with the age at which orchidopexy is performed at freestanding children’s hospitals in North America. Contrary to our expectations, the majority of orchidopexies were still performed after the age of 2 in boys. In addition, this figure remained constant during the study period, despite the presence of guidelines and abundant evidence supporting surgical repair by the age of 1.
The finding that so many orchidopexies are performed outside of the expected time frame points to 1 of 2 basic explanations. In the first scenario, patients with congenital cryptorchidism (ie, patients with UDT at birth) were followed without surgery for longer than is recommended by current guidelines. Such delays could be the result of many factors distinct from medical decision-making, including family delays, insurance coverage issues, or problems with the timing of subspecialty referral. In the second scenario, patients who underwent late orchidopexy primarily comprised cases of acquired UDT (ie, patients whose testes were properly descended at birth but subsequently ascended to an abnormal location). Although long-recognized as a real entity, “ascending testis” is not typically thought of as a common condition, and the fact that more than half of the procedures we observed were performed in older boys suggests that the ascending testis is significantly more prevalent that has been generally recognized. We will address each of these scenarios in turn.
Delays in surgery to treat congenital cryptorchidism are concerning because the evidence for early repair is so strong. The most current guidelines for surgical management of congenital cryptorchidism are based on numerous studies that reveal the long-term consequences of untreated UDT and the advantages of early intervention. Cryptorchid testes tend to be smaller than their normally descended counterparts,15
and 1 trial found that catch-up growth of the cryptorchid testis occurred after orchidopexy was performed at 9 months, but not when surgery was delayed until the age of 3.16
Biopsy at the time of orchidopexy has shown that testicular histology tends to worsen with age.4,5,17
Germ-cell counts may be normal in the newborn period, but if left untreated beyond 2 years of age, intra-abdominal testes have a 30% to 40% chance of complete spermatogenic failure.18
Interstitial fibrosis and poor tubular characteristics are also more common in UDT repaired after 2 years.17
Conversely, both sperm counts and motility have been demonstrated to be higher in young men who had their orchidopexy before 1 year of age.5
If congenitally cryptorchid testes are followed nonoperatively for too long, is there anything that could be done to correct this? The available evidence suggests there is. One successful regional intervention revealed that considerable improvement in timing of orchidopexy can be achieved by heightening awareness of, and adherence to, available guidelines. In that study, before any intervention, 45% of referrals for UDT were initiated by parents, whereas the rest were initiated by local physicians. After the dissemination of educational materials and implementation of an improved system for communicating neonatal examination results, the median age at orchidopexy decreased by 2.5 years.12
Other investigators have found significant variations in the referral patterns of primary care providers, with up to 17% recommending orchidopexy after ages 3 to 10.19
These findings suggest that improvement is both needed and possible.
Regarding our second explanatory scenario (ie, that acquired UDTs are more common than previously assumed), there is evidence that suggests that the frequency of acquired UDT has been underestimated. One intriguing finding has been the apparent mismatch between the reported rates of congenital UDT and surgical orchidopexy. Despite the estimated 0.8% to 1.0% incidence of congenital UDT, some investigators in the United States have estimated that the rate of orchidopexy in the general population is 1.5% to 3% by the age of 17.11,14
In European studies, this figure has been estimated to be as high as 8.4%. These findings suggest that significant numbers of boys become “cryptorchid” later in life, despite having normal examinations at birth. Hack et al20
noted a bimodal distribution of age at which boys are referred for evaluation of UDT, with peaks at ages 2 and 10. They determined that 73% of boys who were referred late for UDT had previous documented normal examination(s).
Although the etiology of ascending testis is unclear, the associated testicular changes may be similar to those seen in children with congenital UDT.21
In published series of ascending testis, the mean age at orchidopexy ranges from 6 to 9 years.22
The natural spasticity of the cremasteric muscles, which peaks at 5 to 8 years of age, may account for a portion of the late orchidopexies; such testes might be better classified as retractile testes.23,24
Agarwal et al23
followed 204 boys with retractile testis and determined that their chance of secondary ascent was 32%. Perhaps most concerning is the finding by Rusnack et al21
that testicular biopsies from congenital and acquired UDT share similar reductions in germ cell counts. In our study, we specifically excluded boys with codes for retractile testis, although coding errors or misclassification may have allowed some of these boys to remain in our cohort.
In addition to the high proportion of late orchidopexies, our results also demonstrate unwarranted variation in the surgical management of UDT. Black and white/Hispanic boys were less likely to undergo orchidopexy by the age of 2 (), as were boys who were publicly insured. The source of these associations is unclear; however, racial disparities in the treatment and outcomes of urologic surgery have been noted previously.25–27
Although important to acknowledge, these relatively small changes in odds do little to explain the overall frequency of late orchidopexies; even the best-case race and payer groups did not come close to meeting the guidelines for orchidopexy timing. The specific mechanisms of these disparities cannot be adequately addressed with our current data and will require more specific investigation. We also observed considerable variability in the age at surgery among hospitals. Such variability may be because of differences in environmental or population characteristics among hospitals, or alternatively, because of modifiable, hospital-specific or health system-specific factors.
Our findings should be interpreted in light of their limitations. Data are limited to tertiary-care, freestanding children’s hospitals that are part of the PHIS system. As such, the patient population may not be generalizable to other academic or community hospitals. We are not aware of any specific important confounders not included in the model; however, given the observational nature of this investigation, there may be unmeasured, confounding influences on our results. Given the magnitudes of the effects seen in our model, the effect of any residual confounding would have to be considerable to render our findings null. No formal sensitivity analyses were performed to estimate the influence of unmeasured confounders. We can only speculate on the reasons for the large variation among hospitals. There may be differences in screening and referral mechanisms within local health care systems not captured by the PHIS database. Conversely, diversity in the proportion of acquired UDT among local patient populations, with or without systems variation, may be present.
Our diagnosis classifications rely on the ICD-9-CM coding system and represent secondary data extracted from the original medical chart. The potential for inaccurate data transfer or improper coding cannot be excluded and must be kept in mind when evaluating these data. This is particularly relevant when considering patients for whom there is missing data. The question of coding is specifically relevant with respect to the question of retractile testes. Although we excluded patients who had this diagnosis, it is possible that some patients with retractile testis were miscoded as having UDT. If widespread, this misclassification would tend to bias the average age at surgery upward because this condition is not typically treated surgically in young boys. However, we believe that the overall number of boys with retractile testis managed surgically at any age should be low, so effects from this bias should likewise be low.