YO2 - Taking Control With The Knife: Managing Brain Metastasis With Gamma Knife In Metastatic Breast Cancer in Pregnancy

Case summary

Gamma Knife (GK) is often used in treatment of oligo brain metastases in patients who have good control of systemic disease. Its role in heavy burden disease has been controversial, let alone in cancer patients who are pregnant.

We reported a 43 years old lady diagnosed with metastatic triple negative breast cancer (TNBC) during pregnancy. She presented in September 2022 with sudden onset of dizziness, persistent vomiting and imbalance. MRI brain confirmed a solitary right cerebellum metastasis, measuring 2.4cm largest diameter. She was pregnant at 22 weeks.

Prior to her current presentation, she was first diagnosed with TNBC in 2016 which she underwent neoadjuvant chemotherapy, surgery and adjuvant radiotherapy. She had local recurrence in 2021, underwent left mastectomy and completed 8 cycles of adjuvant capecitabine.

At the current presentation, X-ray and ultrasound abdomen revealed multiple large cannon ball lesions without evidence of liver metastases. She was beginning to develop mild symptoms of cough and breathlessness.

The patient required urgent intervention to the brain metastases, early commencement of systemic therapy while attempted to preserve her pregnancy to term. She was treated with GK to the solitary brain metastases, 16Gy to 50% isodose, followed by paclitaxel. The radiation dose to the uterus was measured prior and during treatment revealed safe levels of radiation. Her neurological symptoms resolved. She managed to deliver a healthy child via elective Caesarean section uneventfully and completed further chemotherapy post delivery until March 2023.

Serial imaging showed complete response of her brain metastases and partial response of the lung lesions. Unfortunately she succumbed to worsening lung metastases 7 months post GK.

This case highlighted the complexity of managing a patient in pregnancy with symptomatic brain metastasis who required multimodality life saving treatment. Currently there are no guidelines or randomised study to address the use of radiation in pregnancy. However ,there are retrospective case series which suggested that radiation to the brain has become increasingly safer in pregnancy with the emerging of stereotactic radiation treatment.

Clinical trial identification

Editorial acknowledgement