Dear OncoLink "Ask The Experts,"
I am an oncology nurse in Seattle and am 21 weeks pregnant. I recently had a skin exposure to 5FU and was wondering about the implications of that. It was approx 5ccs and I washed the affected area well within 5 minutes. What concerns should I have?
Christina S. Chu, MD, Assistant Professor of the Division of Gynecologic Oncology at the University of Pennsylvania Health System, responds:
Most of the data on chemotherapy exposure in pregnancy is in the form of case reports, or small case series of patients undergoing therapeutic doses of chemotherapy for cancer treatment. While 5-FU is absorbed through the skin, your exposure was relatively small by comparison.
Looking at some of the data for women getting therapeutic doses in pregnancy, there have been two recent case series reported.
A recent study reported in 2006 in the journal Cancer prospectively treated 57 pregnant breast cancer patients with combination 5-FU, cyclophosphamide, and doxorubicin. All patients who delivered had live births. One child had Down's syndrome (this is of course, not related to chemotherapy exposure), one had club foot, and one had ureteral reflux (these are also unlikely to be related to chemotherapy). All children were healthy, and those old enough to be in school were doing well, though 2 had special education needs.
Another study reported in 2005 in the Journal of Clinical Oncology reviewed the 18 year experience at 5 London hospitals for women who received treatment for breast cancer during pregnancy. Of 28 women identified, all but 1 received treatment in the second and third trimesters. Twelve patients received 5-FU containing regimens. Of the patients receiving treatment in the second and third trimesters, fetal outcomes were very good. Median gestational age at delivery was 37 weeks (considered term), and the only anomaly reported was a hemangioma on the abdomen of one child, which was not felt to be related to chemotherapy. None of the children had birth weights below the 10th percentile for gestational age.
Overall, more serious effects are seen after exposure during the first trimester when fetal organs are developing. But even for women receiving therapeutic doses of 5-FU, chemotherapy appears to be safe for both fetus and mother during the second and third trimester.