Mireia Camós

Clonally related follicular lymphomas and histiocytic/dendritic cell sarcomas: evidence for transdifferentiation of the follicular lymphoma clone

Rare cases of histiocytic and dendritic cell (H/DC) neoplasms have been reported in patients with follicular lymphoma (FL), but the biologic relationship between the 2 neoplasms is unknown. We studied 8 patients with both FL and H/DC neoplasms using immunohistochemistry, fluorescence in situ hybridization (FISH) for t(14;18), and polymerase chain reaction (PCR)/sequencing of BCL2 and IGH rearrangements. There were 5 men and 3 women (median age, 59 years). All cases of FL were positive for t(14;18). The H/DC tumors included 7 histiocytic sarcomas, 5 of which showed evidence of dendritic differentiation, and 1 interdigitating cell sarcoma. Five H/DC tumors were metachronous, following FL by 2 months to 12 years; tumors were synchronous in 3. All 8 H/DC tumors showed presence of the t(14;18) either by FISH, or in 2 cases by PCR with the major breakpoint region (MBR) probe. PCR and sequencing identified identical IGH gene rearrangements or BCL2 gene breakpoints in all patients tested. All H/DC tumors lacked PAX5, and up-regulation of CEBPbeta and PU.1 was seen in all cases tested. These results provide evidence for a common clonal origin of FL and H/DC neoplasms when occurring in the same patient, and suggest that lineage plasticity may occur in mature lymphoid neoplasms.

Intensive chemotherapy (high-dose CHOP/ESHAP regimen) followed by autologous stem-cell transplantation in previously untreated patients with peripheral T-cell lymphoma

AIM To analyze toxicity, response and outcome of a phase II trial with intensive chemotherapy plus autologous stem-cell transplantation (ASCT) for young patients with peripheral T-cell lymphoma (PTCL). PATIENTS AND METHODS Forty-one patients [30 males and 11 females, median age 47 years] consecutively diagnosed with PTCL received three courses of high-dose cyclophosphamide 2000 mg/m(2)/day, adriamycin 90 mg/m(2)/day, vincristine and prednisone alternating with three courses of etoposide, cisplatin, cytarabine and prednisone. Responders were submitted to ASCT. RESULTS Sixty-eight percent of patients received the planned treatment. After chemotherapy, 20 patients reached complete response (CR), 4 partial response and 17 failed. ASCT was carried out in 17 of 24 candidates due to lack of mobilization (three cases), toxicity (two), early relapse and patient decision (one each). CR rate after treatment was 51%. With a median follow-up of 3.2 years, 5 of 21 CR patients relapsed and 2 died in CR due to secondary neoplasms. Four-year progression-free survival was 30%. Twenty-two patients have died, with a 4-year overall survival of 39%. International Prognostic Index was the main variable predicting survival. No differences were seen among the 24 candidates according to whether or not they underwent ASCT. CONCLUSION This intensive regimen resulted in moderate CR rate, with manageable toxicity in PTCL. The contribution of ASCT in preventing relapse is debatable. Novel strategies to increase CR warrant investigation.

Primary Cutaneous Small/Medium CD4+ T-Cell Lymphomas: A Heterogeneous Group of Tumors With Different Clinicopathologic Features and Outcome

PURPOSE To define the clinical and pathologic characteristics of primary cutaneous small/medium CD4(+) T-cell lymphoma (PCSM-TCL) and identify parameters of prognostic significance. PATIENTS AND METHODS We have investigated 24 patients with primary cutaneous lymphomas composed of small/medium mature T-cells with a betaF1, CD3, CD4(+) and/or noncytotoxic, CD8(-) and CD30(-) phenotype. The proliferation index and CD8(+) infiltrating cells were quantified with an automated image analysis system. RESULTS Sixteen patients presenting with solitary or localized plaques or small nodules (< 3 cm) had an indolent course. Only three patients experienced repeated cutaneous relapses, and none of them died as a result of the disease after 1 to 168 months (median, 17 months) of follow-up. The tumors had a low proliferation (median Ki-67, 9% +/- 5%) and an intense infiltrate of reactive CD8(+) (median, 20% +/- 11.7%). Five patients presenting with rapidly evolving large tumors or nodules (>/= 5 cm) had an aggressive disease and died with extracutaneous dissemination 18 to 36 months after diagnosis (median, 23 months). These tumors had a significantly higher proliferation (median Ki-67, 22% +/- 11.3%; P < .05) and lower number of infiltrating CD8(+) (median, 1% +/- 3%; P < .05) than the previous group. A third group of three patients had a peculiar clinical presentation with multifocal relapsing lesions without extracutaneous dissemination after a long period of follow-up ranging from 41 to 92 months. Histologically, these cases had an intense infiltrate of eosinophils. CONCLUSION PCSM-TCL is a heterogeneous group of tumors with differentiated clinical and pathological characteristics with impact in the outcome of the patients.

Favorable outcome of patients with acute myeloid leukemia harboring a low-allelic burden FLT3-ITD mutation and concomitant NPM1 mutation: relevance to post-remission therapy

Risk associated to FLT3 internal tandem duplication (FLT3-ITD) in patients with acute myeloid leukemia (AML) may depend on mutational burden and its interaction with other mutations. We analyzed the effect of FLT3-ITD/FLT3 wild-type (FLT3wt) ratio depending on NPM1 mutation (NPM1mut) in 303 patients with intermediate-risk cytogenetics AML treated with intensive chemotherapy. Among NPM1mut patients, FLT3wt and low ratio (<0.5) subgroups showed similar overall survival, relapse risk, and leukemia-free survival, whereas high ratio (≥0.5) patients had a worse outcome. In NPM1wt AML, FLT3-ITD subgroups showed a comparable outcome, with higher risk of relapse and shortened overall survival than FLT3wt patients. Allogeneic stem cell transplantation in CR1 was associated with a reduced relapse risk in all molecular subgroups with the exception of NPM1mut AML with absent or low ratio FLT3-ITD. In conclusion, effect of FLT3 burden is modulated by NPM1 mutation, especially in patients with a low ratio.

Gene Expression Profiling of Acute Myeloid Leukemia with Translocation t(8;16)(p11;p13) and MYST3-CREBBP Rearrangement Reveals a Distinctive Signature with a Specific Pattern of HOX Gene Expression

Acute myeloid leukemia (AML) with translocation t(8;16)(p11;p13) is an infrequent leukemia subtype with characteristic clinicobiological features. This translocation leads to fusion of MYST3 (MOZ) and CREBBP (CBP) genes, probably resulting in a disturbed transcriptional program of a myelomonocytic precursor. Nonetheless, its gene expression profile is unknown. We have analyzed the gene expression profile of 23 AML patients, including three with molecularly confirmed MYST3-CREBBP fusion gene, using oligonucleotide U133A arrays (Affymetrix). MYST3-CREBBP cases clustered together and clearly differentiated from samples with PML-RARalpha, RUNX1-RUNX1T1, and CBFbeta-MYH11 rearrangements. The relative expression of 46 genes, selected according to their differential expression in the high-density array study, was analyzed by low-density arrays in an additional series of 40 patients, which included 7 MYST3-CREBBP AML cases. Thus, genes such as prolactin (PRL) and proto-oncogene RET were confirmed to be specifically overexpressed in MYST3-CREBBP samples whereas genes such as CCND2, STAT5A, and STAT5B were differentially underexpressed in this AML category. Interestingly, MYST3-CREBBP AML exhibited a characteristic pattern of HOX expression, with up-regulation of HOXA9, HOXA10, and cofactor MEIS1 and marked down-regulation of other homeobox genes. This profile, with overexpression of FLT3, HOXA9, MEIS1, AKR7A2, CHD3, and APBA2, partially resembles that of AML with MLL rearrangement. In summary, this study shows the distinctive gene expression profile of MYST3-CREBBP AML, with overexpression of RET and PRL and a specific pattern of HOX gene expression.

Expanded and highly active proliferation centers identify a histological subtype of chronic lymphocytic leukemia ("accelerated" chronic lymphocytic leukemia) with aggressive clinical behavior.

Background The concept of “accelerated” chronic lymphocytic leukemia is frequently used by both pathologists and clinicians. However, neither histological criteria to define this form of chronic lymphocytic leukemia nor its clinical correlates and prognostic impact have been formally defined in large series of patients. Design and Methods Tissue biopsies from 100 patients with chronic lymphocytic leukemia were analyzed for the size of proliferation centers and their proliferation rate as assessed by mitosis count and Ki-67 immunostaining. Histological patterns were correlated with main clinico-biological features and outcome. Results A suspicion of disease transformation was the main reason for carrying out tissue biopsy, which was performed at a median time of 14 months (range, 0 to 204 months) after the diagnosis of chronic lymphocytic leukemia. The biopsy showed histological transformation to diffuse large B-cell lymphoma in 22 cases. In the remaining 78 patients, the presence of expanded proliferation centers (broader than a 20x field) and high proliferation rate (either >2.4 mitoses/proliferation center or Ki-67 >40%/proliferation center) predicted a poor outcome and were selected to define a highly proliferative group. Thus, 23 patients with either expanded proliferation centers or high proliferation rate were considered as having “accelerated” chronic lymphocytic leukemia. These patients displayed particular features, including higher serum lactate dehydrogenase levels and more frequently elevated ZAP-70 than “non-accelerated” cases. The median survival from biopsy of patients with “non-accelerated” chronic lymphocytic leukemia, “accelerated” chronic lymphocytic leukemia and transformation to diffuse large B-cell leukemia was 76, 34, and 4.3 months, respectively (P<0.001). Conclusions The presence of expanded and/or highly active proliferation centers identifies a group of patients with “accelerated” chronic lymphocytic leukemia characterized by an aggressive clinical behavior.

Type I MOZ/CBP (MYST3/CREBBP) is the most common chimeric transcript in acute myeloid leukemia with t(8;16)(p11;p13) translocation

The t(8;16)(p11;p13) fuses the MOZ (MYST3) gene at 8p11 with CBP (CREBBP) at 16p13 and is associated with an infrequent but well‐defined type of acute myeloid leukemia (AML) that has unique morphocytochemical findings (monocytoid blast morphology with erythrophagocytosis and simultaneously positive for myeloperoxidase and nonspecific esterases). RT‐PCR amplification of MOZ/CBP (MYST3/CREBBP) chimera has proved difficult, with four different transcripts found in four reported cases. We studied 7 AML‐t(8;16) patients, 5 with cytogenetically demonstrated t(8;16) and 2 with similar morphocytochemical and immunophenotypical characteristics. Clinically, 3 cases presented as therapy‐related leukemia. Extramedullar involvement was observed at presentation in 2 patients and coagulopathy in 4. The clinicobiological findings confirmed the distinctiveness of this entity. Of note is the erythrophagocytosis in 5 of 7 cases and the immunological negativity for CD34 and CD117 and positivity for CD56. Using a new RT‐PCR strategy, we were able to amplify a specific band of 212 bp in six cases in which sequence analysis confirmed the presence of the previously described MOZ/CBP fusion transcript type I. This is the largest molecularly studied AML‐t(8;16) series, which demonstrates that MOZ/CBP breakpoints are usually clustered in intron 16 of MOZ and intron 2 of CBP. The newly designed single‐round PCR provides a simple tool for the molecular confirmation of MOZ/CBP rearrangement.

ZAP-70 Expression in Normal Pro/Pre B Cells, Mature B Cells, and in B-Cell Acute Lymphoblastic Leukemia

Purpose: The ZAP-70 gene is normally expressed in T and natural killer cells, where it is required for the T-cell receptor (TCR) signaling. More recently, it has been described that ZAP-70 contributes to the B-cell development at early stages of B-cell differentiation in mice. The purpose was to investigate the presence of ZAP-70 in normal pro/pre B cells and mature B cells and in tumoral cells from B-acute lymphoblastic leukemias (B-ALL). Experimental Design: ZAP-70 expression was ascertained by flow cytometry, immunofluorescence, Western blot, and quantitative reverse transcription-PCR. Analysis of ZAP-70 and other signaling proteins of the pre-TCR/TCR was done by Western blot. Results: ZAP-70 was expressed in pro/pre B cells but not in normal mature B cells derived from bone marrow, peripheral blood, or tonsil. Among tumoral cells, ZAP-70 was expressed in 56% of B-ALLs with pro/pre B-cell phenotype and in 4 of 6 Burkitt/ALL lymphomas. In B-ALL cells, expression of CD38 protein correlated with ZAP-70 expression (P = 0.05). Mutational analysis of the ZAP-70 gene revealed the absence of mutations in cases lacking ZAP-70 expression. Moreover, other elements of the pre-TCR/TCR signaling pathway, like LAT and Lck, were also found in B-ALL cells. Conclusions: Among normal B-cell subsets, ZAP-70 was found expressed in normal pro/pre B cells but not in a significant proportion of normal B cells with mature phenotype. Moreover, the presence of ZAP-70 in B-ALLs probably reflects their cellular origin. The lack of ZAP-70 expression in normal mature B cells suggests that its expression in mature-derived neoplasms with different cellular origin, such as Burkitts lymphoma and chronic lymphocytic leukemia, might be due to an aberrant phenomenon.

Correlation between genetic polymorphisms of the hOCT1 and MDR1 genes and the response to imatinib in patients newly diagnosed with chronic-phase chronic myeloid leukemia

The association between seven polymorphisms in the genes hOCT1 and MDR1, encoding for imatinib transporter proteins, and the response to imatinib 400mg/daily was investigated in 65 patients newly diagnosed with chronic-phase chronic myeloid leukemia. The AA genotype at the rs6935207 hOCT1 polymorphic locus was not detected in patients with inadequate response to imatinib. The CC genotype at the rs1045642 (C3435T) MDR1 locus was associated with primary failure, whereas a T allele at the rs2032582 (G2677T/A) MDR1 locus seemed to protect from primary failure. Beside, the MDR1 haplotype 1236T-2677G-3435C was more frequently found in patients primarily resistant to imatinib.

Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

Background Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established. Design and Methods We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoic acid and anthracycline-based chemotherapy enrolled in two subsequent trials of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) and Hemato-Oncologie voor Volwassenen Nederland (HOVON) groups between 1996 and 2005. Results FLT3-internal tandem duplication and FLT3-D835 mutation status was available for 306 (41%) and 213 (29%) patients, respectively. Sixty-eight (22%) and 20 (9%) patients had internal tandem duplication and D835 mutations, respectively. Internal tandem duplication was correlated with higher white blood cell and blast counts, lactate dehydrogenase, relapse-risk score, fever, hemorrhage, coagulopathy, BCR3 isoform, M3 variant subtype, and expression of CD2, CD34, human leukocyte antigen-DR, and CD11b surface antigens. The FLT3-D835 mutation was not significantly associated with any clinical or biological characteristic. Univariate analysis showed higher relapse and lower survival rates in patients with a FLT3-internal tandem duplication, while no impact was observed in relation to FLT3-D835. The prognostic value of the FLT3-internal tandem duplication was not retained in the multivariate analysis. Conclusions FLT3-internal tandem duplication mutations are associated with several hematologic features in acute promyelocytic leukemia, in particular with high white blood cell counts, but we were unable to demonstrate an independent prognostic value in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens.