Liquid Biopsy Spots Aggressive Pediatric Brainstem Cancer Earlier This blood (and spinal fluid) test can help diagnose and monitor the response to treatment for these devastating tumors. There are drugs under development which target the marker mentioned, so this blood test might be able to be used to determine which patients get these new drugs, without the need for biopsies. Amazing stuff. And we are proud to say we are one of the sponsors. Your donations at work!