Which of the following is true concerning breast cancer during pregnancy?
A. Metastases to lymph nodes occur in approximately 75% of patientsBreast cancer occurs in 1 of every 3000 pregnant women, and axillary lymph node metastases are present in up to 75% of these women. Fewer than 25% of the breast nodules developing during pregnancy and lactation will be cancerous. Mammography is rarely indicated because of its decreased sensitivity during pregnancy and lactation; however, the fetus can be shielded if mammography is needed. Chemotherapy administered during the first trimester carries a risk of spontaneous abortion and a 12% risk of birth defects. There is no evidence of teratogenicity resulting from administration of chemotherapeutic agents in the second and third trimesters.