Brain metastases from breast cancer during pregnancy

Brain metastasis during pregnancy is a rare occurrence. In particular, there have only been three prior cases regarding breast cancer metastasis. We report a patient with breast cancer metastasis to the brain during pregnancy and review the literature.

The patient was a 35-year-old female with a history of breast cancer (estrogen receptor/progesterone receptor negative, human epidermal growth factor receptor 2/neu positive, status post-neoadjuvant docetaxel/carboplatin/trastuzumab/pertuzumab therapy, status post-bilateral mastectomies), and prior right frontal brain metastases (status post-resection, capecitabine/lapatinib/temozolomide therapy, and cyberknife treatment). Patient was found to be pregnant at 9 weeks' gestation while on chemotherapy; the patient elected to continue with the pregnancy and chemotherapy was discontinued. At 14 weeks' gestation, she returned with recurrent right frontal disease. She was taken for a craniotomy at 16 weeks' gestation, which confirmed metastases. Six weeks later, patient returned with worsening headaches and fatigue, with more recurrent right frontal disease. She was started on decadron and chemotherapy (5-fluorouracil, adriamycin, and cyclophosphamide). Serial magnetic resonance imaging (MRI) demonstrated enlarging right frontal lesions. She underwent a craniotomy at 27 weeks' gestation, and chemotherapy was discontinued promptly. Starting at 30 weeks' gestation, she received whole brain radiation for 2 weeks. Subsequently, she delivered a baby girl via cesarean section at 32 weeks' gestation. At 6 weeks follow-up, an MRI brain demonstrated no new intracranial disease, with stable postoperative findings.

There is a lack of guidelines and clinical consensus on medical and surgical treatment for breast cancer metastases in pregnant patients. Treatment usually varies based upon underlying tumor burden, location, gestational age of the fetus, and patient's preference and symptomatology.