In the past, most information about breast cancer during pregnancy has been based on anecdotal reports or case-control studies.  However, an ongoing M. D. Anderson study that began in 1989 is providing data from a group of women that has been followed from the time of diagnosis to the present day. Richard Theriault, DO, MBA, a professor of medicine at M. D. Anderson, says the study is the first in the U.S. to look at outcomes for both mother and child.

The study began with a single patient who was diagnosed with breast cancer in her fifth month of pregnancy. She was given two choices: terminate the pregnancy and treat the cancer, or delay treatment until after birth. Since neither was an option, she turned to M. D. Anderson with the mandate of treating her breast cancer while maintaining her pregnancy. "We’ve had pregnancy and breast cancer cases before, but in 1989, the light bulb went off," says Theriault. "We realized that we needed an organized process to obtain information, because otherwise, it’s all anecdotal."

Since then, 39 women have taken part in the protocol, providing precious information for a growing database of treatments and outcomes. Most participants had undergone a modified radical mastectomy or lumpectomy before joining the study. All received a three-drug chemotherapy regimen begun in the second and third trimesters of pregnancy. Ten patients have died and nine others dropped out during the follow-up phase. The remaining 20 women are doing fine, as are the children they bore during cancer treatment, although three of the women have recurrent disease. The oldest child is nearly 11. M. D. Anderson is planning studies to look at long-term survival rates of mother and child, and to determine if any measurable neurological or developmental changes can be detected in children as a result of exposure to chemotherapy in utero. 

The study has revealed that detection and diagnosis is a problem. Most of the participants had Stage II or Stage III breast cancer and larger, more aggressive tumors when they entered the protocol. "Because breast cancer during pregnancy is so rare, many primary care doctors don’t suspect it when patients have a lump," says Theriault. "Also, some doctors refuse to perform mammograms on pregnant women out of concern for the unborn fetus."

"We want to get the word out to primary care doctors that if you have a pregnant woman with a breast lump, a mammogram poses no problem," says Karin Gwyn, M.D., a medical oncology fellow involved in the protocol. "For these women, like all women with breast cancer, early detection is the key. If pregnant women came to us with earlier stage disease, we could do better for them, and hopefully allow them to watch their children grow up."  Gwyn adds that if the abdominal area is shielded during mammography, the procedure is safe for the fetus.

Because of this study, M. D. Anderson has become a mecca for pregnant women with breast cancer. "We get e-mails and calls from all over the world," says Gwyn. "We give special care and attention to this very unique group of breast cancer patients, and I think that draws women to the center."  M. D. Anderson's breast medical oncologists will work closely with your obstetrician. As part of our multidisciplinary approach, we also collaborate with surgeons and radiation oncologists when necessary.  For more information about the protocol, and to see if you are eligible to join, call the M. D. Anderson Breast Center referral specialists at (713) 792-4211.

• Breast cancer in pregnancy is rare, accounting for 2% of all breast cancer cases
• The incidence of breast cancer during pregnancy is likely to increase as more women delay child-bearing
• Mammograms and breast ultrasound were found to be useful in diagnosing breast cancer in our group of pregnant women
• Combination chemotherapy with FAC (5-FU, adriamycin and cytoxan) has been safely administered to women in the second and third trimesters, with minimal complications to mother and fetus