Outcome of Philadelphia Chromosome-Positive Adult Acute Lymphoblastic Leukemia

Abstract
Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) represents the most common cytogenetic abnormality in adult ALL. It is found in 15% to 30% of patients, and its incidence increases with age. As in children, prognosis in Ph-positive adult ALL is poor. No therapeutic approach has had substantial impact on its unfavorable course. We analyzed the characteristics and outcome of newly diagnosed adults with Ph-positive ALL treated at the M. D. Anderson Cancer Center between 1980 and 1997. The diagnosis of patients was based on typical morphological and immunophenotypic criteria of marrow aspirate and biopsy specimens. Cytogenetic and molecular studies were also performed. A total of 67 patients were included in this study. From 1980 until 1991, 38 patients with Ph-positive ALL were treated with vincristine, Adriamycin, and dexamethasone (VAD), or with acute myeloid leukemia (AML)-like induction protocols. Since 1992 a total of 29 patients received induction therapy with an intensified treatment protocol, called “hyper-CVAD”. The outcome of patients treated with standard and intensified treatment regimens was compared and results of our institution contrasted with data obtained from other centers. Ph-positive ALL was present in 67 of 498 patients with newly diagnosed ALL (13%). Patients with Ph-positive ALL had a higher median age (44 versus 34, P=0.007), higher median white blood cell (WBC) counts at presentation (25 versus 8, P=0.0002), and higher peripheral median percentage of blast counts (63 versus 40, P=0.023). FAB subtype L2 (70% versus 49%, P=0.001) and CALLA-positive pre-B immunophenotype (75% versus 37%, PP0.5), median disease-free survival (DFS) was 42 weeks versus 29 weeks (P=0.008), and median survival was 66 weeks versus 45 weeks (P >0.5). Patients with hyper-diploid Ph-positive ALL on hyper-CVAD therapy achieved significantly longer CR duration and DFS than hypo- and pseudodiploid cases (59 weeks versus 42 and 31 weeks, P=0.02 and 0.04, respectively). In contrast, patients treated with regimens prior to hyper-CVAD had significantly shorter CR duration (21 weeks versus 33 and 29 weeks, P=0.03) and DFS with hyperdiploid karyotypes when compared to pseudodiploid and hypodiploid cases (16 weeks versus 30 and 13 weeks, P=0.008). In conclusion, our results demonstrate improved response rate and DFS with current intensive regimens (hyper-CVAD) in patients with Ph-positive ALL, but no advantage in overall survival.