[Indication for Radiotherapy for Breast Cancer Metastasis to the Skull Base Accompanied by Cranial Nerve Palsies].

Distant metastasis to the skull base region frequently manifests various cranial nerve symptoms and reduces patients' quality of life(QOL). We report a 62-year-old woman with skull base metastasis of breast cancer, whose condition clinically improved following palliative radiotherapy. The patient presented to our hospital with hoarseness. CT screening revealed a tumor in the right breast, axial lymph node swelling, and osteoblastic change at multiple sites. A core needle biopsy of the breast tumor revealed invasive lobular carcinoma. She also had nausea, anorexia, vertigo, lower left angle of the mouth, apraxia of lid closing, and dysphagia owing to several cranial nerve palsies. MRI T1- and T2-weighted images showed a diffuse low-signal intensity of the skull base region, and the patient was diagnosed as having breast cancer with symptomatic skull base metastases. Her cranial nerve symptoms improved after 1 week of palliative irradiation to the skull base. We conclude that, even among terminal-stage patients, palliative radiotherapy to the skull base region is an effective treatment option to improve patients' QOL.