Boys with undescended testes at increased risk for testicular cancer
According to a new study, boys with undescended testes, a condition known as cryptorchidism, are at a significantly increased risk for the development of testicular cancer. Researchers affiliated with the University of Glasgow (Glasgow, UK) published their findings online on November 28 in the journal Archives of Disease in Childhood.
The researchers note that approximately 6% of newborn boys are born with undescended testes. While a fetus remains in the uterus, the testes form and develop within the abdominal cavity. Normally, they move down into the scrotum before birth; however, in boys with cryptorchidism, the testes remain in the abdomen. The researchers note that an increased risk of testicular cancer has long been linked with cryptorchidism; previous studies have shown that 5-10% of testicular cancer patients were born with undescended testes. However, it has remained unclear exactly how much a boy’s risk of testicular cancer is increased if he was born with cryptorchidism. Therefore, they conducted a study to evaluate the increased risk.
The researchers conducted a search of the English literature to obtain studies relating to testicular cancer and cryptorchidism, which were published between 1 January 1980 and 31 December 2010, using Embase and Medline databases. A total of 735 research papers were identified and analyzed by four authors independently in accordance with their inclusion and exclusion criteria. Studies reporting an association between cryptorchidism and subsequent development of testicular malignancy were included. Genetic syndromes or other conditions which predisposed to the development of cryptorchidism were excluded.
The researchers selected nine case-control studies and three cohort studies were selected. The case–control studies included 2,281 cases and 4,811 controls. Cohort studies included 2,177,941 boys, with a total of 345 boys developing testicular cancer (total length of follow-up was 58,270 679 person-years). They found that boys with undescended testes were 2.9 times more likely to develop testicular cancer. The authors concluded that boys with isolated cryptorchidism are three times more likely to develop testicular cancer.
The reason for the link between the cryptorchidism and cancer is unclear. Studies have suggested that the temperature elevation experienced by the testes while they are in the abdominal cavity increases the risk of cancer. It also is possible that an underlying hormonal condition predisposes some boys to both cryptorchidism and testicular cancer. Future studies should continue to evaluate this relationship; furthermore, they should examine how men’s risk of cancer is affected by factors such as whether one or both testicles remained undescended at birth, the degree to which the testicles have descended, and whether the condition was corrected with surgery.
Take home message:
This study notes that approximately 6% of newborn boys are born with undescended testes. A number of boys with this condition are undiagnosed. I personally know of a boy who was born at a tertiary medical center and was cared for by a board certified pediatrician. His cryptorchidism was not diagnosed until his pediatrician and the new one discovered the problem. It is a simple matter to check for an undescended testicle. Palpation (gentle squeezing) of the scrotum will reveal whether a testicle is present. It can be accomplished during a bath. Some parents may feel uncomfortable performing this task. If so, ask a healthcare professional to check for cryptorchidism. It can be corrected with a simple operation.
Descent of the testicles is necessary for sperm production, which requires a cooler temperature. If both testicles remain in the abdominal cavity, sterility results.
Reference: Archives of Disease in Childhood