Breast cancer during pregnancy (PABC – Pregnancy Associated Breast Cancer) affects 1/3000 women. Recently, this percentage has increased due to the woman’s gestational age. Newer scientific articles have shown that there is no difference in the prognosis of a woman with PABC and a woman with breast cancer outside of pregnancy, as long as the size, lymph nodes and prognostic indicators are the same. Usually breast cancer during breastfeeding is aggressive. During pregnancy the cancer is usually diagnosed at an advanced stage and is poorly differentiated, does not express hormone receptors and in a percentage of 30% is HER2 positive.
In the event that a pregnant woman feels a lump in the breast, she must immediately undergo a check-up by a specialized mammologist-breast surgeon and have a breast ultrasound performed by a specialized breast radiologist. Mammography can be done by shielding the pregnant woman’s abdomen, in order to minimize the exposure of the fetus to radition. Histologic biopsy is necessary, not FNA cytology. Not enough studies have been done on any side effects of MRI in pregnancy.
Histologically, the majority of women have squamous cell carcinoma with aggressive biological prognostic markers.
For staging, exams are limited to
CT and bone scintigraphy should be avoided especially in the first trimester of pregnancy, as they can cause damage to the fetus.
Magnetic resonance imaging – MRI without contrast can only be done when there is a strong suspicion of liver, bone and brain metastases.
The treatment protocol should resemble as closely as possible the treatment of non-pregnant women. Treatment must be individualized and depends on the biological markers of the cancer, the stage and the month of pregnancy. There is no scientific article that states that termination of pregnancy improves the prognosis.
Termination of pregnancy should be discussed extensively with the patient and suggested in cases where the treatment may harm the fetus or when the woman’s oncological treatment is delayed and may endanger the woman’s life (usually when the diagnosis is made in first quarter).
The surgery can be done during pregnancy and anesthesia does not harm the fetus. The ideal is to perform the surgery in the 2nd or 3rd trimester of pregnancy. In case of a lumpectomy, radiation therapy can be done after delivery. In the event that the surgery is performed during the first trimester, the best solution is a mastectomy because the radiation therapy will be delayed for a long time and puts the pregnant woman at risk. Radiotherapy should not be given during pregnancy.
Chemotherapy should be avoided in the first trimester because it can cause damage and even death to the fetus in a rate of 10-20%. Chemotherapy, if deemed necessary, should be done at the end of the 14th-16th week.
Hormonal therapy is not recommended during pregnancy.
Cancer during pregnancy or breastfeeding can be painful. A mammogram due to the density of the breast, may not be an accurate imaging method. The most accurate test is histologic core needle biopsy along with careful consideration of prognostic factors.