RÉSUMÉ
This was a retrospective study designed to evaluate the frequency and clinical significance of Philadelphia [Ph] chromosome in acute leukaemia. The place and duration of this work was Armed forces Institute of Pathology Rawalpindi from April 1988 to January 1990 and a private medical center from June 1999 to July 2002. A total of 50 cases of acute leukaemia were included in the study. Thirteen cases presenting de-novo ALL and thirty two cases as denovo ANLL [AML and AMML]. Two patients were diagnosed as blast transformation phase of CGL with ALL phenotype whereas 03 cases presented with acute leukaemia transformation from MDS with AML/ AMML phenotype. The samples received were either peripheral blood or bone marrow aspirate. Chromosomal analysis was performed using culture, banding and staining technique. Morphology, clinical findings, therapeutic response and survival were compared in patients with and without the Ph chromosome. Ph chromosome was found to be +ve in 02 newly diagnosed patients presenting with ALL. Ph chromosome in association with additional chromosomal abnormalities persisted in 02 cases transformed into ALL from CGL, and it was found in 05 cases of de novo AML. The study failed to reveal any consistent chromosomal translocation involving chromosome 9 and 22 in 03 AML cases transformed from MDS. Patients with Ph+ ALL differed from those with Ph-ALL in being older, in having more frequent lymphadeno-pathy and splenomegaly and in demonstrating higher initial leucocyte count and more peripheral blasts. Complete remission was obtained in 09 patients with Ph -ve ALL but in only 2 of 4 with Ph +ve ALL. Adults with Ph -ve ALL also survived significantly longer. Five adults with ANLL [AML/AMML] who were Ph +ve did not respond to treatment and survived significantly shorter than adults with Ph -ve AML. No clinical or morphological features indicated which patients with acute leukemia would have Ph chromosome. The Philadelphia chromosome has been considered relatively specific for chronic granulocytic leukaemia. However patients with acute leukaemia [ALL and AML] can also present with positive Philadelphia chromosome. In our study, we have described 09 cases with positive Philadelphia chromosome. Comparison was made with the remaining 41 cases who were Ph negative. Thus it can be concluded that the presence of Ph chromosome in adult acute leukaemia may have biological and clinical significance