Major Finding: Newborns of breast cancer patients who received chemotherapy during pregnancy did not have significantly different outcomes than did newborns of breast cancer patients who did not have chemotherapy.
Data Source: A German Breast Cancer Group registry of 235 women who were diagnosed while pregnant.
Disclosures: No disclosures were given.
BARCELONA — Women who are diagnosed with breast cancer while pregnant can be treated with standard chemotherapy regimens after the 12th gestational week without endangering the health of the fetus, according to data from a registry established by the German Breast Group.
Fetal outcomes were not significantly different when 121 newborns of women who were treated with chemotherapy were compared with 36 newborns of women who did not receive chemotherapy in pregnancy. The findings were presented in a poster at the European Breast Cancer Conference.
“Breast cancer is among the most common cancers diagnosed during pregnancy,” said the lead author Dr. Sibylle Loibl of Johann Wolfgang Goethe University in Frankfurt-am-Main, Germany. Approximately 3% of all breast cancer cases are diagnosed during pregnancy.
“In 2003, we developed the first international guidelines on how to treat breast cancer during pregnancy (Cancer 2006;106:237–46), and we found such limited data that we felt we had to collect more information about this,” she explained.
In all, 235 women with gestational breast cancer were registered in the German database between April 2003 and October 2008.
The investigators' primary aim was to evaluate fetal outcomes 4 weeks after delivery; they also plan to evaluate outcomes in the children and their mothers at 5 years after therapy.
The median age of the women was 33 years (range, 24–46 years). The diagnosis of breast cancer was made during the first trimester in 23.8% of women. Corresponding figures for the second and third trimesters were 39.5% and 36.8%, respectively.
All told, 121 women received cytotoxic chemotherapy during pregnancy. This mostly consisted of anthracyclines in 58.6%, FEC (5-fluorouracil, epirubicin, and cyclophosphamide) in 16.5%, or CMF (cyclophosphamide, methotrexate, and 5-fluorouracil) in 14%. A median of four cycles of chemotherapy was received during pregnancy.
The majority (57.1%) of women had T2 tumors, with T3 tumors found in 25.8%, T1 in 11.5% of cases, and T4 in 4.4% of women who were diagnosed with breast cancer during pregnancy. About half had node-positive disease, and 7.9% had metastatic (M1) disease. Almost two-thirds (63.5%) of breast tumors were negative for the estrogen receptor, with 34.8% identified as being HER2 positive. Most tumors (93.4%) were described as ductal invasive/other.
About half (49.3%) of all newborns in the study were delivered by cesarean section. The median time to delivery was 36 weeks, and Dr. Loibl reported that the median overall birth weight was unaffected by whether or not the mother had received chemotherapy during pregnancy. The median overall birth weight was 2,760 g for 121 newborns who were exposed, and 2,785 g for the 36 newborns who were not exposed to cytotoxic chemotherapy while in utero. No significant differences in postpartum hemoglobin levels were found, with median hemoglobin levels of 16.1 g/dL and 17.2 g/dL, respectively.
Fetal complications occurring within the first 4 weeks after birth in both sets of newborns included signs of infection, anemia, neutropenia, and the need for continuous positive airway pressure (CPAP). Some newborns who were not exposed to intrauterine chemotherapy experienced congenital malformation and icterus, whereas those who were exposed to intrauterine chemotherapy experienced rectal atresia, hyperbilirubinemia, hypoglycemia, and permanent foramen ovale.
“I think pregnant women should and can be treated with standard treatments as recommended by the international guidelines,” Dr. Loibl said. Events that occurred in fetal outcome “were similar in both groups, but we need more information on cytotoxic agents that are more commonly used, such as the taxanes.”
These findings suggest that “there is no harm done to the child when women who are pregnant take chemotherapy,” said Ellen Verschuur-van der Voort, vice president of the Dutch Breast Cancer Association and president of the Europa Donna Forum, the Netherlands.
Ms. Verschuur-van der Voort added that the research gave “a very good and positive conclusion,” offering reassurance to women who are diagnosed with breast cancer while pregnant.