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Background and Objectives: The translocation t(11;14) (q13;q32), typically described in mantle cell lymphomas (MCL), has also been found in some cases of non-MCL lymphoproliferative disorders, such as splenic lymphoma with villous lymphocytes (SLVL), multiple myeloma (MM), prolymphocytic leukemia (PLL), typical and atypical chronic lymphocytic leukemia (CLL and aCLL). In order to define better the genetic features of aCLL with t(11;14), which could represent a distinct disease subset, we looked for genetic lesions in the BCL-1 locus and in BCL-2, BCL-6, c-myc and p53 genes., Design and Methods: We investigated a panel of B-lymphoproliferative disorders with translocation t(11;14)(q13;q32) including nine aCLL, six MCL and one MM. Southern and Northern blot analysis was used to investigate DNA structure and RNA expression; SSCP and direct sequencing were used to detect and characterize p53 point mutations; cytofluorimetric analysis was used to quantify p53 protein., Results: Alterations of BCL-2, BCL-6 and c-myc were not detected. Conversely, BCL-1 rearrangements were present in 4 out of 7 aCLL and in 2 out of 4 MCL. A high incidence of p53 gene alterations was found, almost equivalent in aCLL and MCL., Interpretation and Conclusions: Our results indicate that the occurrence of BCL-1 locus lesions in aCLL selected for t(11;14) is as high as in MCL. Interestingly, rearrangements in the mTC1 (minor translocation cluster 1) were only found in aCLL. Therefore, the two B-cell chronic lymphoproliferative disorders share similar molecular rearrangements and the t(11;14) identifies a subset of B-CLL sharing molecular features with MCL and characterized by aggressive clinical evolution.

Background and Methods: Immunoglobulin (Ig) gene expression and rearrangements provide information about cell lineage, clonality and differentiation of neoplastic lymphoid cells. We performed flow cytometry and Southern blot analysis in 25 patients with chronic lymphocytic leukemia (CLL) from the Po River delta region (Northern Italy), in order to correlate surface immunological phenotype and heavy and light chain gene rearrangements with clinical stages., Results: In these 25 CLL cases, as in the larger group of 165, k-positive (k+) patients were more frequent than lambda-positive (lambda +) ones by a ratio of 59:41, with a predominance of lambda + in stage II (46:54) and of K+ in stage IV (77:23). However, the survival behavior of lambda + and k+ patients was not statistically different. Ig gene rearrangements were found in all patients in accordance with the immunophenotype. When Ig gene analysis was performed on two different occasions in 7 of the 8 who received chemotherapy, there was an increase in the percentage of the germline band. This variation was inversely related to changes in WBC count. In the treated subject who showed a reduction of both WBC count and the germline, there was rapid disease progression and short survival., Conclusions: Analysis of Ig gene rearrangements in our CLL patients demonstrated: i) the monoclonality of neoplastic cells; ii) no correlation between rearrangements and clinical stages, and iii) that this analysis may be a useful tool in evaluating biological behavior in selected CLL cases showing a discrepancy between hematological data and clinical response to therapy.

Clinicopathological and cytogenetic features of two patients with acute myelogenous leukemia (AML) whose blast cells coexpressed myeloid-associated antigens and CALLA are described. Leukemia cells revealed myelomonocytic (FAB-M4) and monocytic (FAB-M5) features, while the nonblast cell population exhibited trilineage myelodysplasia in both cases, a finding suggestive of multiple-cell-lineage involvement. Cytogenetically, a deletion of the long arm of chromosome 6 was found in one patient, and normal metaphases were detected in the other. Molecular studies disclosed a rearrangement of the IgH locus in one patient. Clinically, these patients were unresponsive to antimyeloid regimens including Daunorubicin and Cytarabine, two agents normally also effective on lymphoblastic leukemias, possibly indicating the need for alternative protocols for the treatment of CALLA positive AML.