Breast ca, pregnancy connection unclear. (Survival Rates at Issue).

SAN FRANCISCO -- There's no definitive scientific evidence to support terminating pregnancy in a woman who develops breast cancer, but many obstetricians recommend it anyway, Dr. Mindy Goldman said at a meeting on antepartum and intrapartum management sponsored by the University of California, San Francisco.

"It's still unclear whether women with breast cancer who are also pregnant have similar survival to those who are not pregnant when you compare them stage for stage," said Dr. Goldman of the university.

Less than 3% of new breast cancer cases are diagnosed during pregnancy. There are 3,500 cases in the United States annually and breast cancer is the second most common malignancy diagnosed during pregnancy, she said.

Studies show that survival in breast cancer is often linked to the stage of the disease, but it's unclear whether pregnancy is an independent risk factor. Many of the studies done on survival outcomes in pregnant women with breast cancer have been retrospective, with small numbers. A large case-control study in France showed pregnancy to have adverse effects on survival, but it was unclear whether chemotherapy was withheld because of pregnancy Dr. Goldman said.

Breast cancer does seem to be diagnosed later in women who are pregnant. Breast exams are often more difficult during pregnancy due to engorgement and proliferation of breast tissue and increased vascularity. "It's very easy to confuse benign lesions with cancerous ones," Dr. Goldman said.

Women diagnosed with breast cancer in pregnancy also tend to have a higher incidence of inflammatory breast cancer and an increased frequency of vascular invasion. Small studies also show a higher incidence of HER-2 gene Overexpression in women who are ...