Prevalence of undescended testicles (UDT) is 3-4% at birth. The rate of UDT drops to 1% at 12 months, given that 2/3 of UDT demonstrate descent by age 3 months. The rate of UDT is higher in preterm infants, with no increased risk of malignancy in testes that descend spontaneously in the first 3-12 months. Infants (term or preterm) should be allowed to reach an adjusted gestational age of 12 months before orchidopexy is performed.
Using a meta analysis of current literature, the authors set out to answer 5 questions regarding cryptorchidism:
1. What is the RR of testicular cancer in a cryptorchid or formerly cryptorchid testis?
The historically quoted increased risk for testicular cancer (RR = 48) considered a substantial overestimate. The true RR for testicular cancer was found to be 4-6 in the undescended testes.
2. What is the relative risk for malignancy in the contralateral, normally descended testis?
Historically, it was believed that the contralateral, normal testis has a 5-10% chance of malignancy. Based on current literature, the authors identified no increased risk for malignancy in the contralateral testis.
3. Does relocating the testis affect the type of testicular cancer
Uncorrected cryptorchidism carries a higher risk for seminoma, while a corrected conditions carries a higher risk for non-seminomatous malignancies.
4. Does orchidopexy decrease the risk of malignancy
Relative risk of testicular cancer in the undescended testicle after operative correction depends on patient age at time of orchidopexy. When performed before the age of 10-12 years, the RR of testicular cancer is between 2 and 3. When orchidopexy is performed after age of 12, the RR is 2-6 times that of patients who undergo surgery before age 10-12 (this is comparable to the risk in uncorrected UDT).
5. Is there a risk of malignant degeneration in testicular remnants?
The risk of malignant degeneration from atrophic testes, resulting from perinatal spermatic cord torsion, is minimal.
Reference: Cryptorchidism and testicular cancer: Separating fact from fiction. Wood MW, Elder JS. Journal of Urology (2009);181:452-61
