Breast cancer and brain metastases. There are postoperative findings related to left suboccipital craniotomy. There is a heterogeneous mass in the treatment bed with evidence of intratumoral hemorrhage, which measures up to approximately 35 mm. There is extensive surrounding vasogenic edema. There is associated partial effacement of the fourth ventricle and unchanged mild prominence of the supratentorial ventricles. There are subcentimeter lesions in the left gyrus rectus, left inferior frontal gyrus, right Heschl's gyrus, and medial right occipital lobe. There are skin fiducial markers.
Preoperative MRI shows a dominant left cerebellar hemisphere tumor on the treatment bed and several subcentimeter supratentorial lesions.