Clinical sensitivity to anthracyclines in PH/BCR+ acute lymphoblastic leukemia

Anthracycline dose intensification in adult acute lymphoblastic leukemia: lack of benefit in the context of the fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone regimen

BACKGROUND

In previous studies of frontline therapy for adult acute lymphoblastic leukemia (ALL), early treatment with higher doses of anthracyclines has been reported to improve outcome. The current study was conducted to evaluate whether addition of anthracycline-based consolidation chemotherapy (Course 2) with liposomal daunorubicin (150 mg/m2 intravenously [IV] on Days 1 and 2) and cytarabine (1.5 g/m2 IV on Days 1 and 2) to the standard hyper-CVAD regimen (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high dose methotrexate and cytarabine) would improve outcome.

METHODS

Sixty-eight consecutive adults with de novo ALL or lymphoblastic lymphoma were treated with this modified hyper-CVAD regimen inclusive of rituximab for CD20 expression≥20%.

RESULTS

Sixty-three (93%) patients achieved complete response (CR). With a median follow-up of 90 months, the 5-year CR duration (CRD) and overall survival (OS) rates were 46% and 44%, respectively. Compared with 208 patients treated with standard hyper-CVAD (rates of 45% and 47%, respectively; P=not significant), outcome with the modified hyper-CVAD regimen was not improved overall. Outcome was improved by the addition of rituximab for the CD20-positive subset (rates of CRD and OS of 50% and 53%, respectively), whereas anthracycline intensification worsened outcome for the CD20-negative subset (rates of CRD and OS of 41% and 35%, respectively; P=.01) compared with standard hyper-CVAD. A high mortality rate related to infections in CR was noted among patients aged 60 years or older.

CONCLUSIONS

In the context of the hyper-CVAD regimen, early anthracycline intensification did not improve outcome for adults with de novo ALL or lymphoblastic lymphoma.

Prospective molecular monitoring of BCR/ABL transcript in children with Ph+ acute lymphoblastic leukaemia unravels differences in treatment response

Children with Philadelphia-chromosome-positive (Ph+) acute lymphoblastic leukaemia (ALL) represent a subgroup at very high risk for treatment failure, despite intensive chemotherapy. However, recent retrospective studies showed that Ph+ childhood ALL is a heterogeneous disease with regard to treatment response. We have prospectively monitored, by reverse transcription polymerase chain reaction (RT-PCR) during follow-up, the presence of the BCR/ABL fusion transcript in Ph+ ALL children diagnosed in the Italian multicentre Associazione Italiana Ematologia Oncologia Pediatrica ALL-AIEOP-95 therapy protocol. To our knowledge, this is the first report on the evaluation of minimal residual disease (MRD) in childhood Ph+ ALL prospectively enrolled in an intensive, Berlin-Frankfurt-Munster (BFM)-type treatment protocol. Twenty-seven of 36 (75.0%) Ph+ patients consecutively enrolled into the high-risk group of the AIEOP-ALL protocol between May 1995 and October 1999 were successfully analysed. Twenty were good responders to the pre-phase of prednisone/intrathecal methotrexate treatment (PGR) and seven were poor responders (PPR). Within the PPR group, the RT-PCR monitoring constantly showed positivity for the BCR/ABL fusion transcript and all the patients died of disease progression. In contrast, highly sensitive qualitative RT-PCR monitoring revealed heterogeneity within the PGR group of Ph+ childhood ALL patients. Three different subgroups could be defined, according to the clearance of Ph+ cells within the first 5 months of treatment. This provides useful information on the capability of chemotherapy to reduce the leukaemic clone, with prognostic implications.

Outcome of treatment in children with Philadelphia chromosome-positive acute lymphoblastic leukemia

BACKGROUND

Children with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL) have a poor prognosis, and there is no consensus on the optimal treatment for this variant of ALL.

METHODS

We reviewed the medical records of patients with Ph-positive ALL who were treated with intensive chemotherapy, with or without bone marrow transplantation, by 10 study groups or large single institutions from 1986 to 1996. Data on 326 children and young adults, who ranged in age from 0.4 to 19.9 years (median, 8.1), were analyzed to determine the rate of complete remission and the probability of event-free, disease-free and overall survival according to standard prognostic factors and type of treatment.

RESULTS

The 267 patients who achieved a complete remission after induction chemotherapy (82 percent) were stratified into three subgroups according to the age and leukocyte count at the time of diagnosis: those with the best prognosis (a leukocyte count of less than 50,000 per cubic millimeter and an age of less than 10 years; 95 patients); those with an intermediate prognosis (intermediate-risk features; 92 patients); and those with the worst prognosis (a leukocyte count of more than 100,000 per cubic millimeter; 80 patients). The estimates of disease-free survival at five years (+/-SE) were 49+/-5 percent) for patients with the best prognosis), 30+/-5 percent (for those with an intermediate prognosis), and 20+/-5 percent (for those with the worst prognosis) (P<0.001 for the overall comparison). We also found that transplantation of bone marrow from an HLA-matched related donor offered significantly greater benefit than intensive chemotherapy alone in terms of protecting patients from relapse or other adverse events (relative risk, 0.3; 95 percent confidence interval, 0.2 to 0.5; P<0.001). This finding was consistent in all three groups.

CONCLUSIONS

Unlike the usual type of all, Ph-positive ALL is associated with a poor prognosis. Nevertheless, in some patients with favorable prognosis features, the disease can be be controlled by intensive chemotherapy. Transplantation of bone marrow from an HLA-matched related donor is superior to other types of transplantation and to intensive chemotherapy alone in prolonging initial complete remissions.