Philadelphia chromosome positive adult acute lymphoblastic leukemia: characteristics, prognostic factors and treatment outcome.

Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) is an aggressive form of acute leukemia that represents about one third of all adult ALL. Between 1984 and 1996, forty-three cases of Ph+ ALL (22 males and 21 females) were diagnosed in our institution by successful cytogenetic studies and/or molecular biology. Median age was 42 years (range, 20-71 years) with 28 patients aged below 50 years. Median leukocyte count was 39.7 x 10(9)/l on admission. Tumoral syndrome was seen only in 21 patients (49%) of which 4 cases presented with central nervous system (CNS) involvement. Among the 38 patients classified according to the French-American-British (FAB) criteria, 26 showed L1 and 9 L2 morphology. Three patients showed undifferentiated leukemia. Immunological study at diagnosis only showed B-cell lineage ALL with 95% of patients expressing CD10 and 50% expressing CD20. The Ph+ as sole anomaly was seen in 13 patients (31%), while additional chromosome changes were observed in 28 cases. Two patients were diagnosed only on molecular biology showing a Bcr/Abl rearrangement. Thirty-nine patients treated according to LALA protocols were eligible for the analysis of treatment outcome. Complete remission (CR) was achieved in 25 cases (64%, 95% CI: 47-79%). The median disease-free survival (DFS) and the median overall survival were 6 and 9 months respectively. Relapse was observed in 16 cases (64% of patients achieving CR). Initial parameters associated with a statistically significant worse prognosis were "blastic" fever, hyperuricemia, the presence of an extra Ph chromosome and patients whose marrow does not contain any normal mitosis (AA cases). As post-induction therapy, 13 cases followed a chemotherapy program (group 1) while 11 received early bone marrow (BM) or peripheral stem cell (PSC) transplantation (group 2) (5 allogeneic BM transplantation and 6 autologous BM or PSC transplantation). One patient did not receive any post-induction therapy. In group 1, the median DFS and overall survival were of 5 and 11 months respectively, while they were of 9 months and not reached respectively in group 2 with a 2-year survival rate of 51% (95% CI: 21-83%) confirming the requirement for intensified therapy in Ph+ ALL.