Cryptorchidism is a congenital disease related to testicular descent, and usually affects 1% of boys. It is more common on the right side, and in 25% of cases it is bilateral. Undescended testicles are usually smaller, elongated in shape and soft, compared to those that descend normally.
When does cryptorchidism occur?
The testicles originate from the middle portion of the urogenital cord, and their descent begins at 28 weeks, with the left testicle normally descending first. The stimulus for this to occur is an adequate amount of male hormones.
Classification of undescended testicles according to their cause
Depending on where the cause lies, they can be classified as follows:
- Undescended testis. In this case the testicle is retained anywhere on its way down, so it may or may not be palpable. In 20% of cryptorchid testicles are not palpable, where the testis may be absent due to testicular agenesis or located intra-abdominally.
- Vanishing testis or testicular agenesis. In this situation there is deferens and vessels but no testis.
- Ectopic testis. In this case the testicle is in a place that does not coincide with the normal path of descent, such as the femoral region or the superficial inguinal pouch, among others.
- Retractile testicle, or ascending testicle. The testicle has completed the normal descending process, but tends to ascend due to its low weight, cremasteric activity and the fatty laxity of the groin region.
- Ascended testicle. It is a type of testicle previously identified as descending into the scrotum in a normal manner but now, at school age normally, it is situated high. Although the causes are not clear, it is thought to lie in the deficit of elongation of the cord elements in the growing boy.
How is cryptorchidism diagnosed?
It will be palpation of the inguinal canal that will allow the specialist in Pediatric Surgery to differentiate the ascending testicle that descends into the scrotum and remains there when the retained testicle is released. The laboratory tests that are done, however, will be normal.
In cases where there is bilateral testicular absence an HCG stimulation test will raise testosterone levels if gonadal tissue is present.
Imaging tests such as ultrasound are not always effective, as they have false positives and negatives. On the other hand, laparoscopy will allow checking the presence of testicle or testicular remnants.
Trauma and cryptorchidism
In cases of cryptorchidism there is a greater possibility of trauma and testicular torsion than if the testicle were in a normal situation.
Does cryptorchidism affect fertility?
An increase in testicular temperature as a consequence of a failure in the mechanism of cremasteric thermoregulation causes testicular damage. And this appears to be related to the duration of exposure and how much the temperature rises.
According to various microscopic studies, a decrease in the number of spermatogonia has been observed, as well as a decrease in the mean tubular diameter and atrophy of the Leydig cells. However, these changes are only observed after 2-3 years of life.
What has been proven is that even after orchidopexy, fertility is affected in up to 50% of boys with undescended testicles, and up to 75% of those with bilateral pathology.
Boys with undescended testicles have low fertility rates but the same paternity rate as boys with both testicles descended. In contrast, boys with both testicles undescended will have low fertility and paternity rates.
Is there a greater likelihood of tumors or cancer in undescended testes?
The prevalence of testicular cancer is 0.002% in the normal population. However, the undescended testis is more likely to have malignant changes, with the incidence being higher for intra-abdominal testis compared to inguinal testis. In fact, 10% of testicular tumors occur in testicles that have undergone poor testicular descent. And the same is true for testicular cancer in the contralateral teste of normal position, where the chances of suffering from it are higher.
A study carried out in Sweden on 17,000 treated patients showed that the relative risk of patients suffering from cancer, compared to the normal population, was 2.2 in boys operated on before the age of 13, and 5.4 in those operated on after the age of 13. If surgery is performed before puberty, the risk of testicular cancer is reduced.
How to treat cryptorchidism and when to treat it?
It is advisable to treat cryptorchidism between 12 and 18 months of age. In the past it was common to use HCG treatment before surgery, thinking that, in some cases, it would cause the testicles to descend, but this practice is currently in disuse.
The most common treatments are:
Hormonal treatment of cryptorchidism.
HCG has been used to achieve testicular descent, which occurs in about 20% of cases. However, some recent studies indicate that it is a treatment that favors apoptosis of the germ cells, that is to say, that in some cases it succeeds in making the testicle descend, but at the cost of damaging the germ cells.
But the administration of a substance such as Gonadorelin has been shown to significantly increase the number of spermatogonia, so that this type of hormone could be used to improve the germ cell colony. The use of GnRH prior to orchidopexy improves the fertility index of the testis.
Surgical treatment
This is the most common treatment and is performed under general anesthesia on an outpatient basis. On palpation of the testis in the groin canal, the testis is released via the groin and fixed under a Dartos bag. Then the cremaster should be removed and transfixed stitches in the area of the testicular albuginea are not recommended. On the other hand, if the teste is not palpable in the inguinal canal, laparoscopy is required to confirm or rule out the intra-abdominal location of the testicle, or its absence.
In cases where an intra-abdominal testis is found in an adolescent with a normal contralateral testis, an orchiectomy is performed. Children with intra-abdominal testicles were classically treated with a staged descent, which often resulted in testicular atrophy. Nowadays the technique used is called Stehphen-Fowler and consists of sectioning the testicular vessels, achieving the descent of the testicle into the scrotum with a flap based on the deferens. It is a technique that has a 50-60% success rate if it is performed in a single operation. On the other hand, if it is performed in two stages, the success rate increases to 90%.