Associates in Urology: Topics in Urology: A Concern for Young Cancer Patients

A Concern for Young Cancer Patients

Dr. Eric K. Seaman, MD and David B. Sable, M.D.

A diagnosis of cancer can be devastating at any age. However, it may seem even more overpowering for children or young adults, who may be planning for their future, starting their careers—or considering having a baby.

The most common cancers in young people include Hodgkin's lymphoma and leukemia and in young men, testicular cancer. With increased success rates in treating these cancers, young patients may be concerned about the long-term side effects of the disease and its treatment, and in particular about their ability to become parents after being cured of cancer.

Effects of Cancer and its Treatment
Disease Effects—Any cancer in its advanced stages, especially if accompanied by malnutrition and decreasing overall physical and performance status, may have harmful effects on gonodal function.

Chemotherapy exerts its anti-cancer effect by killing rapidly dividing cells. The high rate of cell division in normal sperm production makes the testicle particularly susceptible to the damaging effects of chemotherapy. The effects can persist for months or years after function has returned to other tissues.

The immature ovary is relatively resistant to chemotherapy, possible due to the higher number of eggs and the smaller percentage of these cells undergoing division compared to the male counterpart. In contrast, older women are more susceptible to the effects of chemotherapy and may sustain premature ovarian failure.

Radiation Therapy—Ionizing radiation damages DNA during cell replication, which prevents the cell from dividing. Even small doses of radiation therapy can be particularly damaging to sperm producing cells in the testis. Altering the fields of external radiation to decrease the scatter effect on the testis and the use of a lead or composite shield to protect the testicle(s) can minimize the chance of testicular injury.

In the ovaries, radiation damage is more likely in older women but can result in either interruption of normal menstruation or premature ovarian failure. If given during childhood, radiation therapy may also have an effect on the growth development of the uterus.

Surgery—Removal of one testicle with cancer should cause no direct harm to the remaining testicle. However, a procedure known as a retroperitoneal lymph node dissection (RPLND), which involves the removal of the lymphatic drainage of the testes, can damage the nerve fibers responsible for seminal emission and ejaculation. Although the sperm production is not directly affected, fertility is impaired. Newer surgical approaches have allowed preservation of ejaculation in approximately 75 to 100 percent of patients. For patients with ejaculatory dysfunction after RPLND, there are various methods to obtain sperm for fertilization including installation of buffers into the bladder to preserve retrograde ejaculation, and the use of certain medications. In cases where ejaculation itself is absent, vibratory stimulation or electrojaculation is helpful.

Surgical treatment for malignancies of the ovaries and uterus can strongly affect female fertility. Newer methods of in vitro fertilization (IVF) have allowed such women to retain their ability to reproduce. Oocyte (egg) donation now allows women who have had their ovaries removed, but still have a functioning uterus, the ability to carry and deliver a viable pregnancy. In addition, women who have undergone a hysterectomy but still have their ovaries, have the option of fertilizing their own eggs through IVF and using a surrogate into whom the embryos are transferred.

Preservation of Fertility
Several strategies are used to protect fertility in cancer patients: attempts to limit the toxicity of the therapy itself, for example using fewer cycles of chemotherapy and for males, cryopreservation (freezing) of sperm.

Some health care providers have looked upon cryopreservation of sperm as a futile attempt to preserve fertility in cancer patients with already abnormal semen parameters, especially because it is known that the process of cryopreservation will further decrease semen quality. However, with advances in assisted reproductive technology, and the ability to inject single sperm into eggs, it is prudent to advise cryopreservation if there are any viable sperm at all in the ejaculate.

In addition, embryos have been successfully cryopreserved for later thaw and transfer, leading to successful pregnancies. Oocyte freezing, however, is in the early stages of development. Currently, the Institute for Reproductive Medicine and Science of Saint Barnabas, is focusing its research efforts on developing new techniques for egg freezing.

Offspring of Cancer Survivors
Of even more concern to cancer survivors is the possibility of inducing mutations or chromosomal aberrations in children of cancer survivors. The obvious question is whether their offspring are more susceptible to spontaneous abortion, or have an increased frequency of genetic diseases, congenital anomalies or a greater tendency to develop cancer in the future. The good new is that so far, there is no firm evidence that any of these consequences occur more frequently than they do in the general population. Damage to reproductive potential can have far-reaching effects on interpersonal relationships, self-esteem and overall quality of life. Through careful pretreatment counseling and proper care to minimize the side effects of therapy without lowering its effectiveness, it is often possible to preserve the potential for parenthood.