Role of Radiation Therapy in Brain metastasis Bongkot Supawongwattana, M.D. Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Breast cancer with brain metas 10-30% of all breast cancer Associated with the shortest survival time Incidence rates are highest in HER2 positive and triple-negative breast cancer Lowest in ER positive tumor Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Symptoms Depend on location of tumor – Headache – Vomiting – Hemiparesis – Ataxia – Blur vision Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Diagnostic imaging To identify tumor – Location – Size – Number CT with contrast or MRI brain Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

CT brain with contrast Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

MRI brain Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Management Corticosteroids : Dexamethasone – Less mineralocorticoid effect – Less likely to associated with infection or cognitive dysfunction – Reducing peritumoral edema  relief symptom Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Management Chemotherapy – Ineffective due to poor BBB penetration Surgery Radiation therapy Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Radiation therapy Mainstream therapy for brain metastasis Whole brain irradiation (WBRT) – Giving alone – Post-operative RT Stereotactic radiotherapy Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Radiation therapy WBRT alone – Poor performance status – Life expectancy < 3 mo – 30 Gy in 10 Fx – 20 Gy in 5 Fx – Median survival 3-6 mo Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Radiation therapy Combined surgical resection and WBRT more effective than WBRT alone – Median survival 8-16 mo – Local recurrence rate 7-15 % Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Radiation therapy During and immediately after RT – Lesion may appear to grow slightly – Can worsen peritumoral edema – Require prolonged steroid Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Guideline for brain metastasis in breast cancer patient Symptom suspected brain metastasis CT or MRI brain as initial investigation Confirmed brain metastasis - Start dexamethasone IV - Other supportive medication Single lesionMultiple lesion Consult Neuro-surgeon - Role of tumor resection Consult Radiation Oncologist - Role of palliative RT Appropriate for tumor resection Inappropriate for tumor resection Remove tumor followed by PORT

Radiation therapy process Simulation : thermoplastic mask Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

Radiation therapy process Radiation planning : 2D technique Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University

RT dose 200 cGy x 20 Fx 200 cGy x 15 Fx 300 cGy x 10 Fx 400 cGy x 5 Fx 650 cGy x 2 Fx 800 cGy x 1 Fx Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University Depend on multiple factors : -Performance status -Age -Convenient

Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University