Thanks to a new medical discipline known as oncofertility, the reproductive outlook for women cancer patients is becoming as good as for men, who long have had the option of banking their sperm, according to Teresa K. Woodruff, PhD, of Northwestern University Feinberg School of Medicine in Chicago, in her lecture “Oncofertility: The Preservation of Fertility Options for Young People with Cancer.” A promising new technique for preserving ovarian tissue has the potential to safeguard the future fertility even of very young girls undergoing cancer treatment, she said.
Dr. Woodruff, the Thomas J. Watkins professor of obstetrics and gynecology at Northwestern, coined the term “oncofertility” to describe oncologists and reproductive specialists working hand-in-hand to preserve patients’ fertility while treating their disease. She is the leader of the Oncofertility Consortium, which draws on cutting-edge research to counsel patients on fertility options. Headquartered at Northwestern and supported by the National Institutes of Health, the Consortium operates through more than 50 centers in 29 states.
About 140,000 people under age 45 are diagnosed with cancer each year in the United States, Dr. Woodruff said. “There are no good numbers for how many are threatened with loss of fertility, because it depends on the course of the disease and treatment prescribed,” she said.
Chemotherapy affects fertility by attacking follicles in the ovaries that contain a woman’s lifetime supply of eggs, Dr. Woodruff explained. Because follicles grow rapidly, they are especially sensitive to cancer drugs, which target fast-growing cancer cells. If drugs damage only mature follicles and the eggs they contain, a woman may stop having periods during treatment but resume menstrual cycles after she completes chemotherapy. But if drugs destroy all the follicles, she will be left sterile.
Radiation treatment to the abdomen can damage the follicles, as well as the uterus. If directed to the head, radiation can impact fertility by blocking production of reproductive hormones in the brain.
Many women with cancer who want to safeguard their fertility opt for egg or embryo banking, which oncofertility specialists are making available to more patients. “Egg banking also is much more effective now than five or ten years ago, because we can freeze the eggs better,” Dr. Woodruff said.
However, egg banking is not suitable for girls who have not yet gone through puberty or for women who cannot postpone cancer treatment while they take hormones to stimulate production of mature eggs. A new option called ovarian tissue cryopreservation sidesteps these problems. Doctors remove an ovary via laparoscopy, an outpatient surgery that takes 30 to 45 minutes. The procedure requires no hormones and does not delay cancer treatment for more than a couple of days. Tissue from the removed ovary is sliced into strips, frozen, and stored. Because a girl is born with all the eggs she will ever have, this technique could be used on a child as young as one year of age, Dr. Woodruff said.
Following cancer treatment or whenever a woman is ready to have a child, the ovarian tissue can be thawed and transplanted back into her body. “Worldwide, there have been about 20 live births resulting from this procedure, including those among some cancer patients,” Dr. Woodruff said. Because transplantation does carry the potential risk of reintroducing cancer cells back into the body, it is not recommended for women who have had ovarian cancer or blood system cancers, such as leukemia or lymphoma.
Researchers are working hard to perfect a safer use of preserved ovarian tissue called in vitro follicle maturation, which may be available in several years. “Instead of growing follicles in a woman’s body, we grow them in a dish,” Dr. Woodruff explained. “That would allow us to eliminate the possibility of reintroducing the cancer she’s just survived. We’ve produced live, healthy offspring in mice and have gotten good quality eggs in both baboons and rhesus monkeys. Human follicles also have adapted rapidly to the in vitro system. They grow rapidly and are fairly easy to work with.”
# # #
The American College of Obstetricians and Gynecologists is the nation’s leading group of physicians providing health care for women. As a private, voluntary, nonprofit membership organization of approximately 53,000 members, The American College of Obstetricians and Gynecologists strongly advocates for quality health care for women, maintains the highest standards of clinical practice and continuing education of its members, promotes patient education, and increases awareness among its members and the public of the changing issues facing women’s health care.