Pearls and Oy-sters: Salt and Pepper Sign, PLNTY for Drug-Resistant Epilepsy

Drug resistant epilepsy, defined as the failure of two or more antiseizure medications to achieve seizure freedom, is responsible for 2/3 of epilepsy cases. Tumors are responsible for up to 15% of all adult onset and up to 6% of childhood onset epilepsies. Amongst these tumors, commonly known subtypes: DNET, ganglioglioma, and low-grade astrocytoma are often suspected. New advances in tumor classification have been made, with genetics playing a key role in tumor classification. Polymorphic Low-grade Neuroepithelial Tumor of the Young (PLNTY) are a highly epileptogenic subtype of tumors that may mimic low-grade gliomas but offer pathological and genetic clues: oligodendroglioma-like cellular components and infiltration patterns, and strong CD34immunopositive stain. In addition, a key finding is radiological: a unifocal abnormality best seen on MRI Brain in FLAIR sequence as the “Salt and pepper sign” as well as calcifications appreciated in Computed Tomography head.