What is your differential diagnosis for this mass?
Metastasis, lymphoma and primary brain tumour.
Which is most likely?
Metastasis as it lies at the grey-white matter and is roundish in shape. Lymphoma could also be considered as it is slightly hyperdense and homogeneously enhancing.
In the left parieto-occipital region is a homogeneously and vividly enhancing mass. It has slightly lobulated contours and is isodense to gray matter on the non-contrast images. Extensive surrounding vasogenic oedema.