Lung cancer with history of a brain metastasis that received SBRT on 5/19/2016. There is a 12 mm diameter peripherally enhancing lesion in the anterior left frontal lobe, which also measured 12 mm in diameter on the prior exam. However, there is an associated 7 mm wide nodular enhancing component on the anterolateral aspect, which previously measured up to 4 mm. Otherwise, the confluent area of surrounding vasogenic edema has perhaps slightly diminished in extent. A moderate degree of scattered cerebral white matter T2 hyperintensity without enhancement likely represent chronic small vessel ischemic disease. There is no evidence of or acute infarct. The ventricles and basal cisterns are unchanged in size and configuration. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, paranasal sinuses, and scalp soft tissues are grossly unremarkable.
A 12 mm diameter peripherally enhancing metastatic lesion in the anterior left frontal lobe, has not significantly changed. However, the associated 7 mm wide nodular enhancing component on the anterolateral aspect, previously measured up to 4 mm. While tumors can sometimes transiently increase in size after radiation therapy, focal tumor progression is certainly a consideration. Otherwise, the confluent area of surrounding vasogenic edema has perhaps slightly diminished in extent. 