Fertility in Men Diagnosed with Cancer
Who needs to consider preservation of Fertility?
a. The American Cancer Society estimates that 760,000 men will be diagnosed with cancer in 2009. Cancer itself (before treatment) is sometimes associated with less sperm production in men. This is specially the case in Hodgkin’s lymphoma, testicular cancer, prostate cancer, leukemias and colon cancer. The most harmful factor, however, is cancer treatment. Chemotherapy and radiation significantly impair sperm production. The effect of chemotherapy depends on age, drug used, dose and duration. Cyclophosphamide appears to be the most harmful agent. Radiation also impairs sperm production especially at doses of 1200cGy or more.
Sperm count sometimes recover to a variable extent years after cancer treatment. This depends on the type of cancer and treatment used. For example 90% of men diagnosed with Hodgkin’s lymphoma, treated with MOPP chemotherapy regimen, do not have any sperm in the ejaculate after one year.
b. Bone marrow transplantation for cancer of nonmalignant diseases usually require prior irradiation and chemotherapy. This is associated with high risk (85%) of complete failure of sperm production.
c. Connective tissue / autoimmune diseases as lupus and rheumatoid arthritis requiring treatment with chemotherapy.
d. Genetic abnormalities associated with rapid loss of male germ cells e.g. Kleinefelter syndrome, Y chromosome microdeletion (AZFc).
Methods used for Fertility Preservation
Methods used to preserve fertility in men are generally divided into two categories:
Protection of the testes from damage caused by cancer treatment:
1. Shielding the testes from radiation field.
2. Protection of the testes from the effect of chemotherapy.
GnRH agonists are a group of medications that suppress the master gland in the brain, preventing the release of the hormones that stimulate sperm production in the testes. Although suggested, there is no proof that they actually increase the odds for pregnancy after the use of chemotherapy. Actually, there is no effective protective medication available for use in men or women.
Low Temperature Storage of Sperm and Testicular Tissue:
a. Sperm Cryopreservation. This is the standard method for preservation of fertility in men. A sperm sample is obtained by masturbation and frozen for later use. If feasible multiple samples are obtained. In the future, sperm sample are used for intrauterine insemination or IVF / intracytoplasmic sperm injection (ICSI). Banking sperm was found to offer not only a chance to father children in the future but also encouragement and improved morale during disease treatment especially if it was initiated by the patient own initiative.
Lack of information and counseling is the most important reason why men diagnosed with cancer do not bank their sperm.
Although freezing may reduce the quality of sperm especially if it was not optimal before freezing, modern reproductive medicine can handle the majority of compromised specimens yielding excellent pregnancy rates, similar to those of fresh sperm.
b. Testicular Sperm Extraction (TESE). This surgical procedure retrieves sperm from inside the testes if no sperm was found in the ejaculate. If this procedure is used before cancer treatment, sperm are retrieved in over 50% of cases. Sperm or testicular biopsies are frozen for later use. ICSI is used for fertilization. In case of testicular cancer, sperm retrieval can be performed at the same time of surgery for cancer.
c. Testicular Tissue or Germ Cell Freezing. This is an experimental technique. Immature germ cells or testicular pieces are frozen for later transplantation. No pregnancy was achieved using this method so far.
In conclusion, fertility-sparing strategy is readily available to the majority of men at risk for diminished fertility through sperm cryopreservation. Men interested in fathering children in the future should be counseled about this option.