Female, 69 years old, with right-sided weakness, known left hemispheric brain tumor with question of petechial hemorrhage. Significant interval expansion of a large tumor is evident spanning the left temporal and parietal lobes. Whereas previously, the lesion was largely solid and minimally enhancing, there is now a prominent central necrotic core and a thick irregular enhancing rim. The lesion inclusive of the enhancing portions measures up to 79 x 45 x 58 mm. Enhancing components of the lesion do correlate with elevated rCBV.Within the lesion core, strong susceptibility artifact is seen along with scattered small areas of T1 hyperintensity, all of which likely reflect the presence of intratumoral blood product. Outside of the tumor core, no definite or significant parenchymal hemorrhage is seen.T2 hyperintensity and mass effect within the parenchyma surrounding the lesion core have increased substantially. Signal abnormality now fills the left temporal lobe and also occupies a large portion of the left occipital and parietal lobes. Signal abnormality tracks through the white matter capsules and into the left cerebral peduncle and left thalamus. A midline shift of 12 mm to the right is seen with subfalcine herniation. Left uncal medialization is also noted. However, no significant transtentorial herniation is evident at this time.The left temporal horn appears to be dilated and likely entrapped. Effacement of the left ventricular atrium is seen. Both lateral ventricles are otherwise slightly more prominent than on the prior examination. A few additional scattered foci of white matter T2 hyperintensity are relatively unchanged.
Since the prior MRI examination, the left temporoparietal lesion has significantly increased in size with development of a central necrotic core and a thick irregular rim of enhancement. A marked increase in surrounding signal abnormality and mass effect is also seen. Given the recent completion of RT/TMZ, the possibility that this may represent pseudoprogression could be entertained. However, blood volume mapping and the gross morphology of the lesion would favor tumor progression.