Newer technology such as droplet digital PCR can identify mutations like MYD88 and can be resulted faster, but they can only be utilized if the clinician is highly suspicious of PCNSL.15 In this report, the patient’s diagnosis was unknown in the setting of her MPNST, and the benefit of using a test like MSK-IMPACT is that it targets a wide variety of oncogenes and tumor suppressor genes to help narrow down a diagnosis. This evidence concerns the gene MYD88 and primary central nervous system lymphoma.