Results of conventional-dose cytosine arabinoside and idarubicin in elderly patients with acute myeloid leukemia

Prognosis of elderly patients with acute myelogenous leukemia: analysis of 126 AML cases

We retrospectively analyzed 126 acute myelogenous leukemia (AML) patients aged > or =60 years who had all been referred to the same hematological department between 1989 and 1999. In 76 de novo AML cases, 53 patients (median age, 72 years) were treated with combination chemotherapy (CT) for remission induction. Complete remission (CR) rate was 57.1%. The median overall survival (OS) was 16 months, and the rate of 3-year OS was 28%. The favorable prognostic factors were performance status < or =2, cholinesterase > or =100 IU, and intermediate or favorable karyotype (P < .01). Seventeen patients (median age, 78 years) with hypocellular bone marrow or poor general condition were treated with low-dose cytosine arabinoside (LDAraC). In these patients, the CR rate was 50% and the median OS was 11 months, with an OS estimate at 3 years of 14%. All patients with hypocellular bone marrow who received LDAraC for 21 days achieved CR. In 50 patients who developed AML following a myelodysplastic syndrome (MDS/AML), 22 patients (median age, 74 years) were treated with CT, and 14 (median age, 74 years) patients were treated with LDAraC. The CR rates were 22.7% and 21.4%, respectively, and the median OS durations were 8 months and 11 months, respectively. There were no significant factors that would indicate a good prognosis in MDS/AML patients.

Malignancy: Tumor Suppressor Gene Aberrations in Acute Myelogenous Leukemia

Acute myelogenous leukemia is a heterogeneous disease that appears to evade the normal regulatory controls of tumor suppressor genes. Studies in AML have documented mutations in both p53 and Retinoblastoma (Rb) genes, but these mutations are relatively uncommon, especially compared to their mutational frequency in solid tumors. In addition, expression abnormalities have now been documented in several tumor suppressor genes or related genes including MDM2, p73, Rb, p14(ARF), p15(INK4B), and p16(INK4A). We review the current literature regarding tumor suppressor genes in AML and suggest how these genes may be involved in the development of the disease.

FLT3, RAS, and TP53 mutations in elderly patients with acute myeloid leukemia

The prevalence and significance of genetic abnormalities in older patients with acute myeloid leukemia (AML) are unknown. Polymerase chain reactions and single-stranded conformational polymorphism analyses were used to examine 140 elderly AML patients enrolled in the Southwest Oncology Group study 9031 for FLT3, RAS, and TP53 mutations, which were found in 34%, 19%, and 9% of patients, respectively. All but one of the FLT3 (46 of 47) mutations were internal tandem duplications (ITDs) within exons 11 and 12. In the remaining case, a novel internal tandem triplication was found in exon 11. FLT3 ITDs were associated with higher white blood cell counts, higher peripheral blast percentages, normal cytogenetics, and less disease resistance. All RAS mutations (28 of 28) were missense point mutations in codons 12, 13, or 61. RASmutations were associated with lower peripheral blast and bone marrow blast percentages. Only 2 of 47 patients with FLT3 ITDs also had a RAS mutation, indicating a significant negative association between FLT3 and RAS mutations (P = .0013). Most TP53 mutations (11 of 12) were missense point mutations in exons 5 to 8 and were associated with abnormal cytogenetics, especially abnormalities in both chromosomes 5 and 7. FLT3 and RAS mutations were not associated with inferior clinical outcomes, but TP53mutations were associated with a worse overall survival (median 1 versus 8 months, P = .0007). These results indicate that mutations in FLT3, RAS, or TP53 are common in older patients with AML and are associated with specific AML phenotypes as defined by laboratory values, cytogenetics, and clinical outcomes.

Acute myelogenous leukemia and aging. Clinical interactions

Effective treatment of the elderly patient with AML remains a challenging task. Acute myelogenous leukemia is clearly a different disease in the elderly than in the young, for many reasons, both clinical and biologic, which contribute to the worse prognosis in the elderly. The elderly, as a group, have been underrepresented in clinical trials. Several important prognostic variables have been identified and described, however, that can help the physician select the appropriate treatment for any individual patient. Age itself should not preclude an attempt at therapy, especially for AML, which progresses very rapidly in the absence of treatment. After careful analysis of prognostic factors, in any individual patient, however, the outlook may be so poor that it may be desirable to withhold treatment. With a better understanding of the pathophysiology of AML in the elderly, more targeted and less toxic treatment regimens will become available. At present, however, clinicians must use an improved understanding of the disease to predict its behavior in an individual patient, so that the currently available treatment modalities are used most prudently.

Dyshematopoiesis in de novo acute myeloid leukemia: cell biological features and prognostic significance

Dyshematopoiesis was found in 44 (42.3%) of 104 cases of de novo acute myeloid leukemia (AML). Dyshematopoietic AML (dys-AML) and AML without hematopoietic dysplasia (non-dys-AML) were compared with regard to biological, hematological, immunophenotypic, and cytogenetic parameters as well as prognostic criteria. Median age of patients was 55 years in both groups. In dys-AML, the median leukocyte count (p = 0.04), peripheral blast (p = 0.02) and medullary blast cell count (p < 0.001) were significantly decreased, whereas the median platelet count (p - 0.04) was increased. Immunophenotyping demonstrated that leukemic blast cells in dys-AML more frequently expressed the adhesion molcules CD54 (p = 0.05) and CD58 (p = 0.08) than leukemic cells in non-dys-AML. Cytogenetically, we distinguished two karyotypic patterns, one group with a normal karyotype or prognostically favorable single chromosome aberrations ("P(0)-karyotype"), and another one with unfavorable single aberrations or complex aberrations ("P(1)-karyotype"). The incidence of these groups was not significantly different between dys-AML and non-dys-AML. Complete remission rate (CRR) after induction chemotherapy (p = 0.03) and overall survival time (OS; p = 0.03) were significantly lower in dys-AML. In addition, median disease free survival (DFS; p = n.s.) was inferior compared to non-dys-AML. In the dys-AML as well as in the non-dys-AML patient group, CRR, DFS, and OS were decreased in the P(1)-compared to the P(0)-subgroup. We conclude that dyshematopoietic AML is characterized by specific cell biological features and that hematopoietic and cytogenetic status represent complementary prognostic factors in de novo AML.

Acute myeloid leukemia in the elderly: a critical review of therapeutic approaches and appraisal of results of therapy

In the elderly, acute myeloid leukemia (AML) is characterized by a poorer prognosis than in younger patients, due to either host related factors (poor performance status, co-morbid diseases, organ function impairment) or the biology of leukemia itself (high incidence of adverse cytogenetic abnormalities, high frequency of preceding myelodysplastic syndromes, intrinsic resistance to cytotoxic drugs). Current therapeutic results are mostly unsatisfactory and studies reporting high rates of complete remission are probably influenced by selection biases as suggested by the low rate of elderly patients inclusion into cooperative trials. Availability of intensive support including hematopoietic growth factors could stimulate clinicians to manage an increasing number of elderly patients with AML with aggressive programs. However, chemotherapy in the elderly is difficult, costly and usually associated with high morbidity and mortality rate. Therefore, all efforts should be made to identify those subset of elderly patients in whom aggressive treatment may result in a true improvement of disease free and overall survival. The critical analysis of our five years experience, as reported here, seems to suggest that older AML patients displaying unfavourable prognostic factors at diagnosis (i.e., adverse karyotype and high serum LDH levels), but clinically eligible for intensive chemotherapy, do not actually benefit from an aggressive approach. A blind attempt to treat these patients aggressively may be associated with a life threatening toxicity not counterbalanced by an actual survival advantage. We suggest therefore that aggressive treatment should be reserved for elderly AML cases in whom the presence of good prognostic factors at diagnosis predicts that the loss of some patients due to toxicity may be balanced by the achievement of a substantial proportion of long term survivors. Finally, given the biological and clinical heterogeneity of elderly AML patients, a more precise prognostic categorization of these patients would be particularly useful in interpreting future therapeutic results.

Cytosine arabinoside, etoposide and aclarubicin (AVA) for the treatment of acute myeloid leukemia (AML) in elderly patients

BACKGROUND

Elderly patients (age > or = 60 years) with acute myeloid leukemia (AML) have unfavourable prognoses when polychemotherapy regimens are used, because therapy response is characterized by low remission rates, short remission duration and high toxicity.

PATIENTS AND METHODS

A phase II trial in elderly AML patients was conducted to determine the efficacy of two induction courses of a moderately-dosed combination of aclarubicin (25 mg/m2, 30 min i.v., days 1-4), etoposide (100 mg/m2, 30 min i.v., days 1-3) and conventional-dose cytosine arabinoside (ara-C, 100 mg/m2, c.i.v., days 1-3 and 30 min i.v., q 12 hours, days 4-7) (AVA-7), followed by one consolidation treatment using a reduced-dose schedule over five days (AVA-5) after three months in CR.

RESULTS

Thirty-two AML patients with a median age of 66.2 years (range 60-76) were included in the study: three of them had histories of preexisting myelodysplasia and one of polycythemia vera. Following 1-2 courses of AVA-7 17 patients (53%) achieved CR, two PR (6%), and nine had resistant disease (28%); the overall response rate was thus 59%. Toxicity was significant but acceptable, with an overall treatment-related death rate of five of 32 patients (16%) after 63 courses of AVA. The median disease-free survival (DFS) was 12 months, and the median survival of all patients was 16.6 months.

CONCLUSIONS

These results indicate that the combination of aclarubicin, etoposide and conventional-dose ara-C is effective in elderly AML patients. The relatively brief remission duration requires new consolidation and maintenance therapy approaches.