Neuroradiology Board Review – Brain Tumors – Case 3
Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.
More description and the answer (spoiler!) are seen below the video.
This case shows a single image from a head CT as well as some MRI images at the same level. There is a dominant mass in the left parietal lobe which has some internal blood products. There is surrounding edema, but not much enhancement as most of the T1 hyperintensity is intrinsic (present on the pre-contrast exam) from blood products/methemoglobin. Upon closer inspection, there is also a smaller enhancing nodule in the adjacent cerebral hemisphere.
The diagnosis is: metastatic disease
Metastases to the brain are common manifestations of malignancies elsewhere in the body. The most common diseases to cause brain metastases are the same as the most common systemic cancers, including lung cancer, breast cancer, and melanoma. When brain metastases have hemorrhage, you might think about melanoma, renal cancer, and thyroid cancer (among others).
The most common locations for brain metastases are in the cerebral hemispheres and cerebellum. About 50% of brain metastases are solitary, so don’t be fooled if you see only a single lesion. It can still be a metastasis.
The differential diagnosis for most metastatic lesions includes infection and high grade glioma. Demyelinating disease can also sometimes have a similar appearance.