Do not delay breast cancer therapy during pregnancy

Do not delay treatment of breast cancer just because a woman is pregnant, said lead researcher Sibylle Loibl, Dr. med, of the German Breast Group.

This suggestion is based on study results detailing the effects of different treatment options on the infant. Loibl presented this data at the 33rd Annual CTRC-AACR San Antonio Breast Cancer Symposium, held Dec. 8-12, 2010.

"At the time we started the study in 2003, there was hardly any information on breast cancer therapy during pregnancy, but we felt there was a medical need for it," she said.

Although the incidence of pregnancy among breast cancer patients is small (about 2 to 3 percent), women are delaying childbirth until later in age, which may increase the instances of cancer cases among pregnant women, according to Loibl.

The researchers collected data from women diagnosed with breast cancer while pregnant to see how the infants fared.

From April 2003 until June 2010, they collected data from 313 women, aged 23 to 47 years old. The women had various subtypes of breast cancer, and the cancer was in various stages when diagnosed. All of the women were pregnant when they were diagnosed with cancer: 23 percent were in the first trimester, 42 percent were in the second and 36 percent were in the third trimester. Some women received various treatment regimens while the rest received chemotherapy.

Two of the infants died shortly after birth and 29 did not continue the pregnancy. Premature deliveries were more common among women who did not receive chemotherapy than among women who did receive chemotherapy. In addition, the infants of the women who received chemotherapy tended to weigh a little more than those who did not receive chemotherapy.

Infants from both groups experienced congenital problems, most of which were related to premature birth.

"We were surprised about the number of congenital malformations," Loibl said. "It is about 1 to 3 percent in the general population, but was higher in this cohort."

Although the study was primarily focused on the infant outcomes, the researchers also looked at the treatment effects on the women and found that the median overall disease-free survival of the mothers was 27 months and median overall survival was 55 months.

Based on these results Loibl said she would advise her pregnant cancer patients to "continue the pregnancy and start with a treatment as closely as possible to standard recommendations for nonpregnant women." In addition, it is critical that a multidisciplinary team in close collaboration with an obstetrician, prenatal care specialist and a neonatologist treat the pregnant woman with breast cancer.