Breast Cancer: How it Affects Fertility (cont.)
Type and Stage of Cancer
How advanced a cancer is upon detection, as well as what type it is, dictate whether chemotherapy will be required, thereby affecting the risk of side effects to the ovaries.
The more advanced the cancer upon detection, the greater likelihood that chemotherapy, which affects the whole body, will be used to treat it. For instance, invasive breast cancer typically requires systemic chemotherapy, whereas a small tumor with small nodes that is localized and contains a minimal threat of spreading may not.
The type of tumor also impacts a patient's treatment options. Some breast cancers can be treated with the use of hormone-containing drugs. But a small percentage of breast cancer tumors are "hormonally insensitive," explains Susan Domcheck, MD, assistant professor of medicine at the University of Pennsylvania. What does this mean? "You can't use hormones to treat them. You're left with chemotherapy as your only option."
Age of Patient
Age plays a big role in patients' future fertility. "The age of the woman at the start of systemic chemotherapy is the biggest predictor of infertility," Barbierri tells WebMD. But why?
"If you're 30, your fertility is already declining. Add to that chemotherapy, and you tack on a few more years. We know that chemotherapy induces menopause, particularly with women over 40," Domcheck says.
Despite the fertility risks associated with breast cancer treatment (chemotherapy in particular), methods to preserve fertility prior to treatment offer hope to many patients.
To date, freezing embryos (fertilized eggs) created by in vitro fertilization (IVF) is the most widely used and effective method of preserving fertility. But there are potential downsides. IVF takes three to four weeks, a delay in cancer treatment that, depending on the stage and type of cancer, patients may or may not be able to afford. Sperm -- either from a partner or donor -- must be made available immediately to fertilize the eggs. And IVF is expensive -- anywhere from $10,000 to $14,000 per cycle.
Other methods of fertility preservation, albeit experimental, show promise. Egg freezing, which applies the same concept as embryo freezing, has proven less effective -- most likely because eggs are smaller, and less hardy, than embryos. There's also ovarian suppression during treatment, which "protects ovaries to some degree from chemical onslaught of chemotherapy," Barbierri tells WebMD. Freezing entire strips of ovarian tissue is a third technique under investigation; it involves surgically removing, storing, and later replacing the tissue in another part of the body.
Tamoxifen, a drug traditionally used to prevent breast cancer reoccurrence, was recently found to stimulate ovaries in breast cancer survivors during an IVF cycle, enhancing both egg and embryo production. This extra boost can combat infertility barriers such as age and the diminishing ovarian reserves, which occurs naturally with aging, notes Oktay.