When my mom first got chemotherapy, we were told that at one point, a CNS prophylaxis would be done. This is chemotherapy given to the central nervous system (CNS) as a preventative treatment. A lumbar puncture (also known as a spinal tap) is performed and chemotherapy is inserted into her spine. The reason they do this is because there is a barrier that prevents normal chemotherapy from entering the spine and brain. I guess "Go Brain!" for protecting itself. Our first doctor, Dr. Grant Lewis, indicated that most times with Adult Acute Lymphoblastic Leukemia patients, a CNS prophylaxis is done even if no cancer has been detected in the brain or spinal cord. It is for preventative measure since cancer presence in the central nervous system is quite a critical affair.My mom was originally scheduled to have the lumbar puncture and CNS prophylaxis tomorrow. However, presence of blasts (bad white blood cells) in her peripheral blood stream has halted this procedure. The team of doctors at City of Hope have "concern of seeding the CNS ( due to presence of leukemic blasts in Peripheral blood)." Also, Hyper CVAD Part B includes two drugs, methotrexate and cytatabine, that enter the brain and CNS, so the CNS prophylaxis is not currently needed. She will have her CT scan on Friday and will be admitted for her 2nd round of chemotherapy on Monday. While all this happens, her siblings will be tested for stem cell match. If there is a match, the transplant will probably happen in 2 months, after chemotherapy cycle 2 (called Hyper CVAD Part B) and satisfactory remission.