A child diagnosed with acute lymphocytic leukemia (ALL) is under chemotherapy. Which of the following is a BAD prognostic sign of ALL?

Children aged 1-9 years whose diagnostic WBC count is less than 50,000/microliter, standard risk ALL, have an event-free survival (EFS) in the 90% range, while children 10 years of age or older have an EFS of approximately 88%. Other high-risk factors for ALL: Non-T-cell disease Adverse cytogenetics Extramedullary disease Failure to achieve remission within 30 days of treatment Ref: Graham D.K., Quinones R.R., Keating A.K., Maloney K., Foreman N.K., Giller R.H., Greffe B.S. (2012). Chapter 31. Neoplastic Disease. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.