M4 acute myeloid leukemia: the role of eosinophilia and cytogenetics in treatment response and survival. The GIMEMA experience.

BACKGROUND: Myelomonocytic acute myeloid leukemia (M4-AML) is frequently associated with the cytogenetic marker inv(16) and/or the presence of eosinophilia. The aim of this study was to analyze the incidence and prognostic role of these factors in a large series of patients. DESIGN AND METHODS: Adult patients with acute myeloid leukemia consecutively enrolled in the GIMEMA trials AML10 and LAM99p were retrospectively analyzed. RESULTS: Among 1686 patients, 400 cases of M4-AML were identified; of these, 78% had neither eosinophilia nor inv(16), 6% had eosinophilia only, 8% had inv(16) only and 8% had both. Univariate analysis showed that both eosinophilia and inv(16) were correlated with a higher probability of complete remission, lower resistance to chemotherapy and increased overall survival. Multivariate analysis showed that the simultaneous presence of the two factors significantly increased the probabilities of both complete remission and overall survival. The presence of only one of the two factors also increased the probabilities of complete remission and overall survival, but not to a statistically significant extent. The relapse-free survival of the responding patients was not influenced by the two factors. CONCLUSIONS: In a large series of patients with M4-AML we confirmed the favorable role of inv(16), but the weight of this factor among the whole M4 population was of limited relevance. Eosinophilia, which affects a small proportion of cases, also emerged as a favorable prognostic factor. Based on the results of this large case population, overall and relapse-free survival rates of patients with M4-AML are not significantly better than those of patients with non-M4 AML, while the concomitant presence of both inv(16) and eosinophilia was associated with a significantly improved prognosis.

Loss of heterozygosity in acute leukemia: evidence of frequent submicroscopic deletions.

Although chromosomal abnormalities are detected by conventional cytogenetic analysis (CCA) in 40-60% of patients with acute myeloid leukemia (AML), cryptic chromosomal deletions may only be detected by molecular analysis. To determine their frequency, we studied 74 cases of AML by microsatellite allelotype assay using 35 microsatellites spanning eight chromosomal regions known to be frequently involved in AML. In 42 (57%) we found DNA imbalance at the screened loci. This was detected by CCA only in 4 cases. Our data show that cryptic deletions are a common event in AML.

Rituximab improves the efficacy of high-dose chemotherapy with autograft for high-risk follicular and diffuse large B-cell lymphoma: a multicenter Gruppo Italiano Terapie Innnovative nei linfomi survey.

PURPOSE: To investigate the impact of adding rituximab to intensive chemotherapy with peripheral-blood progenitor cell (PBPC) autograft for high-risk diffuse large B-cell lymphoma (DLB-CL) and follicular lymphoma (FL). PATIENTS AND METHODS: Data were collected from 10 centers associated with Gruppo Italiano Terapie Innnovative nei Linfomi for 522 patients with DLB-CL and 223 patients with FL (median age, 47 years) who received the original or a modified high-dose sequential (HDS) chemotherapy regimen. HDS was delivered to 396 patients without (R-) and to 349 patients with (R+) rituximab; 154 (39%) and 178 patients (51%) in the R- and R+ subsets, respectively, underwent HDS for relapsed/refractory disease. RESULTS: A total of 355 R- (90%) and 309 R+ patients (88%) completed the final PBPC autograft. Early treatment-related mortality was 3.3% for R- and 2.8% for R+ (P = not significant). Two parameters significantly influenced the outcome: disease status at HDS, with 5-year overall survival (OS) projections of 69% versus 57% for diagnosis versus refractory/relapsed status, respectively, and rituximab addition, with 5-year OS of 69% versus 60% in the R+ versus R- groups, respectively. In the multivariate analysis, these two variables maintained an independent prognostic value. The marked benefit of rituximab was evident in patients receiving HDS as salvage treatment: the 5-year OS projections for R+ versus R- were, respectively, 64% versus 38%, for patients with refractory disease or early relapse and 71% versus 57%, for patients with late relapse, partial response, or second/third relapse. CONCLUSION: The results of this large series indicate that rituximab should be included in the current practice of PBPC autograft for DLB-CL and FL.

Submicroscopic deletions at 7q region are associated with recurrent chromosome abnormalities in acute leukemia.

BACKGROUND AND OBJECTIVES: Loss of heterozygosity (LOH) on the long arm of chromosome 7 (7q) has been frequently reported in several types of human cancer including hematologic malignancies. Moreover, monosomy of chromosome 7 and 7q deletions have been associated in acute myeloid leukemia (AML) with aggressive disease and poor prognosis. DESIGN AND METHODS: Using a panel of 11 polymorphic microsatellite markers at bands 7q21-q36, we investigated fifty patients (acute myeloid leukemia [AML], n=33 and acute lymphoid leukemia [ALL], n=17) for LOH, a hallmark of possible involvement of tumor suppressor genes. In parallel, the same acute leukemia (AL) cases were studied by conventional cytogenetics. RESULTS: A total of 48 spots of allelic loss were observed in 16 (32%) out of 50 patients (AML, n=11 and ALL, n=5). Among LOH+ve cases 3 showed chromosome 7 monosomies, whereas no cytogenetically detectable abnormalities were observed in chromosome 7 in the remaining 13. INTERPRETATION AND CONCLUSIONS: Comparison with karyotypic results indicated that presence of LOH at 7q21-q36 was significantly associated with other chromosomal aberrations. In fact, an altered karyotype was detectable in 87% of LOH+ve and in 52% of LOH(-ve) AL cases (p=0.024). In addition, LOH at 7q was prevalently associated with unfavorable cytogenetic lesions (p=0.013). Our study represents the first report of a significant association between LOH and recurrent chromosomal abnormalities in AL patients suggesting that the 7q21-q36, region may be an unstable area prone to chromosome breakage in patients with an abnormal karyotype.