Demographics and Outcome of Philadelphia-positive ALL in a Pediatric Population in North India: a Single-center Experience

Philadelphia-positive (Ph+) acute lymphoblastic leukemia (ALL) in children had a worse outcome before the use of tyrosine kinase inhibitors. We have evaluated the demographics and outcome of Ph+ ALL patients treated with imatinib without blood marrow transplantation. Of the 206 children with ALL registered for treatment, the demographic data of 15 Ph+ ALL patients were compared with the remaining Ph- patients. Imatinib (340 mg/m(2)) was started on day 5 (D5) of induction in Ph+ patients, and their overall survival was compared with Ph- high-risk patients treated on similar protocols. Statistical analysis was carried out by the Fisher exact test and the t test. The Kaplan-Meier test was used for survival analysis. Philadelphia positivity noted in 15/206 (7.28%) ALL patients was higher than reported earlier. Median initial total leukocyte count and central nervous system positivity were significantly higher in Ph+ patients. Myeloid markers, CD13 and CD33, were also positive in 33.3% Ph+ patients. D15 and D35 marrow showed remissions in a larger proportion of Ph+ ALL, as compared with Ph- patients, but chemotherapy interruptions and neutropenic deaths were significantly higher after starting imatinib, as compared with Philadelphia high-risk patients. Overall survival was similar in Ph+ and Ph- high-risk ALL patients. Ph+ ALL, noted in 7.28%, presented with high initial white blood cell counts, high central nervous system positivity, poor steroid response, and higher induction deaths, as compared with high-risk Ph- ALL, and raised the question about the appropriate dose and time of introduction of imatinib to prevent toxicity.