The male reproductive system is made up of the scrotum, testicles, vas deferens, epididymis, seminal vesicles, prostate gland, penis, and urethra. The reproductive system is controlled by the pituitary gland in the brain. The testicles are located in the scrotum (the loose pouch of skin that hangs behind the penis). The testicles are made up of Leydig cells (cells that produce the male hormone - testosterone) and germ cells (cells that produce sperm).When a boy enters puberty, the pituitary gland releases two hormones (FSH and LH) that signal the testicles to begin producing sperm and testosterone. As puberty progresses, testosterone causes deepening of the voice, enlargement of the penis and testicles, growth of facial and body hair, and muscular development of the body. Sperm produced by the testicles mature in the epididymis (a coiled tube that sits on top of each testicle) and then travel into the vas deferens (sperm storage area). The seminal vesicles and prostate gland produce fluids that mix with the sperm to create semen. When a man ejaculates, sperm are pumped out through the vas deferens, mixed with fluids from the prostate and seminal vesicles, and exit the body through the urethra (tube that carries fluids out of the penis).
The most common effect of cancer therapy on the male reproductive system is infertility (the inability to initiate a pregnancy). Infertility can occur as a result of certain types of chemotherapy, radiation to the brain or testicles, or surgery involving the male reproductive system.Another possible effect of cancer therapy on the male reproductive system is testosterone deficiency, also known as “hypogonadism” or “Leydig cell failure.” This is the inability to produce enough of the male hormone, testosterone, and can result from damage to the Leydig cells or pituitary gland caused by radiation to the testicles or brain. If this occurs in a young boy, he will not be able to go into puberty without the help of hormones prescribed by a doctor. Males who develop testosterone deficiency after puberty will need hormonal therapy in order to maintain their muscular development, bone and muscle strength, proper distribution of body fat, sperm production, sex drive, and potency.
Chemotherapy of the “alkylator” type (such as cyclophosphamide, nitrogen mustard and procarbazine) may cause infertility. The total dose of alkylators used during cancer therapy is important in determining the likelihood of damage to spermproducing cells. The higher the total dose, the more potential for developing infertility. If alkylating chemotherapy was used in combination with radiation, the risk of infertility may be increased.Radiation therapy can affect testicular function in two ways:
Males who have had cancer treatments that place them at risk for reproductive problems should have a yearly check-up that includes careful evaluation of their hormone and puberty status. Blood may be tested for hormone levels (FSH, LH, and testosterone). If any problems are detected, a referral to an endocrinologist (hormone specialist), urologist (specialist in the male reproductive organs) and/or fertility specialist may be recommended.Males with low testosterone levels should receive testosterone replacement therapy. Testosterone is available in several forms, including gels, skin patches, and injections. Your endocrinologist will determine which form of therapy is best for you.
Infertility is not related to sexual function. In some men with infertility, there may be a decrease in the size or firmness of the testicles, but in others, there are no physical indications of infertility.
Males who had surgical removal of both testicles will not be able to make sperm, and infertility will be permanent. In other males, the only sure way to check for sperm production is to have a semen analysis performed, which checks the appearance, movement and concentration of sperm in the semen. A semen analysis that shows azoospermia (no sperm in the semen sample) on more than one sample is a likely indicator of infertility.In men who have azoospermia as a result of radiation, return of sperm production is unlikely. However, in men who have azoospermia as a result of chemotherapy, the effect on male fertility is highly variable. Recovery of sperm production may occur months or years after the completion of chemotherapy. For others, the damage may be permanent. It may be impossible to determine if sperm production will resume at some time in the future, especially if chemotherapy ended only a few years prior to the semen analysis. For this reason, males who have azoospermia from chemotherapy should always assume they can make a woman pregnant.
If semen analysis shows no sperm, and fertility is desired, consult with a doctor who specializes in male infertility. Medical advancements dealing with male infertility are being made. Recently, surgeons have been able to locate areas of active sperm production in the testes of men who were thought to be azoospermic. Surgical harvesting of the sperm has allowed conception with techniques devised for men with absent or very low sperm counts. Occasionally, azoospermia may be unrelated to chemotherapy altogether, and treatment for another disorder may be indicated.
Options for using banked sperm depend on the amount and quality of material saved. Men who banked sperm prior to cancer treatment will need to work with a doctor specializing in reproductive medicine, so that the cryo-preserved (frozen) sperm can be used in an optimal manner.Another option for males who produce no sperm may be donor insemination. This results in pregnancy with a child that is biologically related only to the mother. Additional options include adoption of a biologically unrelated child or child-free living.
Although fertility and testosterone production are not usually affected if only one testicle was surgically removed, you should take precautions to protect the remaining testicle from injury by always wearing an athletic supporter with a protective cup when participating in any activities that may potentially cause injury to the groin area (such as contact sports, baseball, etc.). If your remaining testicle was treated with radiation, or if you received chemotherapy that can affect testicular function, the effects of these treatments are the same as discussed above.