According to results presented at the 40th annual meeting of the American Society of Clinical Oncology (ASCO), chemotherapy during the second and third trimesters of pregnancy in women diagnosed with breast cancer does not appear to harm the fetus.
Being diagnosed with breast cancer during pregnancy is uncommon. Due to its uncommon occurrence, data involving treatment with chemotherapy during pregnancy is relatively scarce and researchers continue to slowly build on existing data regarding this issue. The biggest fear of receiving chemotherapy during pregnancy is harm or even death to the fetus. Furthermore, postponing treatment of a pregnant woman raises the risk that the cancer will become more advanced and ultimately more likely to result in a poorer prognosis. However, research continues to indicate that some chemotherapy regimens administered in the second and third trimesters may pose no threat to the growing fetus, while optimizing long-term outcomes for the mother.
Researchers from England recently reviewed records from 28 women who were diagnosed with breast cancer during their pregnancy. All women were treated with chemotherapy during their second and third trimesters (except one who was treated during her first trimester). Chemotherapy consisted of anthracycline-based regimens (doxorubicin or epirubicin) or consisted of the regimen referred to as CMF (cyclophosphamide, methotrexate, 5-fluorouracil). Women received chemotherapy either prior to surgery or following surgery. Seventeen patients underwent surgery during their pregnancy, while some patients underwent surgery following delivery. The majority of women had stages II and III breast cancer, and the average number of chemotherapy cycles delivered was 4. Of the 27 patients who received chemotherapy during their second and third trimesters, no birth defects occurred. The one patient who received chemotherapy during her first trimester suffered a spontaneous abortion (miscarriage). The average weight of the babies was over 6 pounds and the average delivery occurred on the 37th week of pregnancy.
The researchers concluded that even though this was a small group of women, these results add to a growing body of evidence that chemotherapy delivered during the second and third trimester of pregnancy does not appear to harm the fetus. Other results have indicated, however, that chemotherapy administered during the first trimester of pregnancy may pose significant risks to the fetus. Women who are diagnosed with breast cancer during pregnancy should discuss their individual risks and benefits of treatment including chemotherapy with their healthcare provider.
Reference:Ring A, Ellis P, Jones A, et al. Chemotherapy for breast cancer given during pregnancy: A case series. Proceedings from the 40th annual meeting of the American Society of Clinical Oncology. 2004. Abstract No: 715. © CancerConsultants.com