Updated: November 2004

Since breast cancer is the most common tumour occurring in women during the reproductive years, carcinoma of the breast in pregnancy does occur and presents special management problems. It is, fortunately, relatively unusual and each case deserves consideration on its own merits. It is extremely important to assess the potential for cure in an individual patient. The welfare of the patient and the fetus needs to be evaluated. Diagnosis of breast cancer in pregnancy can be very difficult. New localized masses merit at least ultrasound examination and fine needle aspiration biopsy. For staging chest radiograph can be performed with abdominal and pelvic shielding.

1)Stage I or II

First Twelve Weeks

Definitive therapy of breast cancer during this phase of pregnancy may endanger the fetus and therefore a therapeutic abortion is usually recommended. The treatment of the malignancy will then proceed as in the non-pregnant state. Patients who decline termination should be treated by a modified radical mastectomy. No adjuvant radiation therapy should be given during pregnancy. Chemotherapy with AC chemo has been given in this situation, but is avoided if possible, unless the risks of withholding chemo outweighed the risks to the fetus. Referral is recommended to assess the need for further treatment after the baby has been delivered.

Twelve to Twenty-eight Weeks

During this interval the breast cancer can be adequately treated surgically without terminating pregnancy. Modified radical mastectomy is the treatment of choice. Adjuvant radiotherapy is contraindicated during pregnancy. The risk of recurrence should be estimated based on the pathology of the tumor. If the risk of relapse is high then adjuvant chemotherapy may be given.Cyclophosphamide and doxorubicin with or without 5-fluorouracil is the preferred combination during pregnancy. Epirubicin and taxanes should be avoided. Tamoxifen exposure in the first and second trimesters may be associated with genitourinary abnormalities and therefore should be avoided. Referral of these patients for assessment is recommended.

Twenty-eight Weeks to Term

Maturity of the fetus should be assessed. Consideration should be given to inducing labour as soon as obstetric advice indicates that the fetus is viable. Initial treatment by modified radical mastectomy is appropriate and as soon as the fetus has been delivered the patient should receive additional treatment as for the non-pregnant state. Chemotherapy may be given during pregnancy (see above)  but in most circumstances is delayed until after delivery.

Lactation

When a carcinoma arises during lactation, lactation should be terminated and therapy appropriate for the treatment of the malignancy instituted.

2) Locally Advanced or Inflammatory Breast Cancer

Patients with advanced disease pose a special problem. In the early weeks of pregnancy consideration has to be given to termination of the pregnancy. If the patient is in the second trimester and is still hoping to deliver a viable child then chemotherapy with drugs least likely to harm the fetus may be considered (see above). Referral to BCCA is recommended. Radiotherapy is contra-indicated except in exceptional circumstances.



More information on Chemotherapy Drugs and Pregnancy