Her experience stresses several key factors that must be considered in this situation. Her patients received chemotherapy at a mean of 20 weeks’ gestation – safely outside the critical early period. Only two women received chemotherapy before 10 weeks; both were treated before they knew they were pregnant. Both children born of these pregnancies were considered well. One with intrauterine exposure to cytarabine was developmentally normal at age 7 years. The other, who was exposed to oxaliplatin and capecitabine, was normal at age 2 years.
Treatment also was stopped a mean of 40 days before delivery, to allow the mother’s bone marrow to fully recover before giving birth.
A second U.S. study was reported at the 2011 meeting of the American Society of Clinical Oncology. A poster by Dr. Jennifer Litton and her colleagues examined physiological outcomes in 81 children exposed to chemotherapy for maternal breast cancer. The mothers had taken a standardized chemotherapy regimen of 5-fluorouracil, doxorubicin and cyclophosphamide (FAC) given during the second and third trimesters (J. Clin. Oncol. 2011;29[May 20 suppl.]:abstract 1099).
One child was born with Down syndrome, one with a club foot, and one with ureteral reflux. Three parents reported language delay in later follow-up surveys. Other reported health issues included 15 children with allergies and/or eczema, 2 with asthma, and 1 with absence seizures.
Dr. Litton, a breast oncologist at the University of Texas M.D. Anderson Cancer Center in Houston, also cowrote a 2010 review of breast cancer treatment in pregnancy, in which she discusses maternal and fetal outcomes from several cohorts, and the possible impact of intrauterine exposure to a variety of chemotherapy agents (Oncologist 2010;15:1238-47).
Risks Vary With Cancer Type
Breast cancer during pregnancy may be the simplest to treat. If the cancer is caught very early, it may be reasonable to delay treatment until the fetus has passed the critical first trimester, waiting until organs are formed and the risk of chemically induced damage is reduced, Dr. Temkin said. "It’s safe to do breast surgery during pregnancy and it’s safe to give chemotherapy after the first trimester."
But physicians can miss a new breast tumor during a prenatal exam, so some present at a more advanced stage, according to Dr. Amant, who is also the lead author of the Lancet’s breast cancer report (Lancet 2012;379:570-9).
Infiltrating ductal adenocarcinomas account for more than 70% of the breast cancers diagnosed during pregnancy. These can be aggressive, said Dr. Amant. Estrogen receptor status is probably no different in pregnant and nonpregnant women.
If the tumor is discovered early and is pathologically favorable, chemotherapy probably can be delayed until 14 weeks’ gestation, allowing nearly complete fetal organogenesis without worsening the mother’s outcome. Women also may elect an early termination if the pathology is unfavorable, or for other personal reasons, Dr. Temkin said. "I think a lot of it depends on when the cancer is diagnosed. Patients of mine who already have a diagnosis and then become pregnant almost always elect to terminate. But if the cancer is discovered when the pregnancy is farther along, most will continue, especially if the woman is highly emotionally invested," she noted.
Tougher Cancers, Tougher Choices
Dr. Sarah Temkin
Treating gynecologic cancers during pregnancy often comes down to a choice between the mother’s health and maintenance of the pregnancy, Dr. Temkin said. "The standard of care for ovarian cancers is surgery or radiation to the pelvis, where the fetus is. Cervical cancer is treated with a hysterectomy or radiation, and neither treatment is compatible with keeping a pregnancy. Neoadjuvant therapy is not considered standard of care for these tumors. These are complex decisions for the patient: ‘Do I accept a different treatment [that might not be as effective] or maintain the pregnancy?’ "
In early cervical cancers without nodal spread, the most common tactic is close observation with periodic imaging to rule out spread; therapy is given after delivery, Dr. Phillippe Morice wrote in the Lancet section’s review on gynecologic malignancies (Lancet 2012;379:558-69).
"Delayed treatment until fetal maturation for patients with stage IA disease has an excellent prognosis and is now the standard of care," wrote Dr. Morice of the Institut de Cancérologie Gustave-Roussy in Villejuif, France.
Locally advanced disease is often not compatible with pregnancy. "The main treatment choice is either neoadjuvant chemotherapy or chemotherapy and radiotherapy. In pregnant patients, this approach means that the pregnancy must be ended before the initiation of therapy, but in exceptional cases in which surgery to end the pregnancy is not technically feasible ([that is], a bulky cervical tumor), radiation therapy can be delivered with the fetus in utero, resulting in a spontaneous abortion in about 3 weeks," he wrote.