Alessandro Pulsoni

BRAF Mutations in Hairy-Cell Leukemia

BACKGROUND Hairy-cell leukemia (HCL) is a well-defined clinicopathological entity whose underlying genetic lesion is still obscure. METHODS We searched for HCL-associated mutations by performing massively parallel sequencing of the whole exome of leukemic and matched normal cells purified from the peripheral blood of an index patient with HCL. Findings were validated by Sanger sequencing in 47 additional patients with HCL. RESULTS Whole-exome sequencing identified five missense somatic clonal mutations that were confirmed on Sanger sequencing, including a heterozygous mutation in BRAF that results in the BRAF V600E variant protein. Since BRAF V600E is oncogenic in other tumors, further analyses were focused on this genetic lesion. The same BRAF mutation was noted in all the other 47 patients with HCL who were evaluated by means of Sanger sequencing. None of the 195 patients with other peripheral B-cell lymphomas or leukemias who were evaluated carried the BRAF V600E variant, including 38 patients with splenic marginal-zone lymphomas or unclassifiable splenic lymphomas or leukemias. In immunohistologic and Western blot studies, HCL cells expressed phosphorylated MEK and ERK (the downstream targets of the BRAF kinase), indicating a constitutive activation of the RAF-MEK-ERK mitogen-activated protein kinase pathway in HCL. In vitro incubation of BRAF-mutated primary leukemic hairy cells from 5 patients with PLX-4720, a specific inhibitor of active BRAF, led to a marked decrease in phosphorylated ERK and MEK. CONCLUSIONS; The BRAF V600E mutation was present in all patients with HCL who were evaluated. This finding may have implications for the pathogenesis, diagnosis, and targeted therapy of HCL. (Funded by Associazione Italiana per la Ricerca sul Cancro and others.).

Follicular Lymphoma International Prognostic Index 2: A New Prognostic Index for Follicular Lymphoma Developed by the International Follicular Lymphoma Prognostic Factor Project

PURPOSE The aim of the F2 study was to verify whether a prospective collection of data would enable the development of a more accurate prognostic index for follicular lymphoma (FL) by using parameters which could not be retrospectively studied before, and by choosing progression-free survival (PFS) as principal end point. PATIENTS AND METHODS Between January 2003 and May 2005, 1,093 patients with a newly diagnosed FL were registered and 942 individuals receiving antilymphoma therapy were selected as the study population. The variables we used for score definition were selected by means of bootstrap resampling procedures on 832 patients with complete data. Procedures to select the model that would minimize errors were also performed. RESULTS After a median follow-up of 38 months, 261 events for PFS evaluation were recorded. beta2-microglobulin higher than the upper limit of normal, longest diameter of the largest involved node longer than 6 cm, bone marrow involvement, hemoglobin level lower than 12 g/dL, and age older than 60 years were factors independently predictive for PFS. Using these variables, a prognostic model was devised to identify three groups at different levels of risk. The 3-year PFS rate was 91%, 69%, and 51% for patients at low, intermediate, and high risk, respectively (log-rank = 64.6; P < .00001). The 3-year survival rate was 99%, 96%, and 84% for patients at low, intermediate, and high risk, respectively (P < .0001). CONCLUSION Follicular Lymphoma International Prognostic Index 2 is a simple prognostic index based on easily available clinical data and may represent a promising new tool for the identification of patients with FL at different risk in the era of immunochemotherapy.

ABVD versus BEACOPP for Hodgkin's Lymphoma When High-Dose Salvage Is Planned

BACKGROUND BEACOPP, an intensified regimen consisting of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone, has been advocated as the new standard of treatment for advanced Hodgkins lymphoma, in place of the combination of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). METHODS We randomly assigned 331 patients with previously untreated and unfavorable Hodgkins lymphoma (stage IIB, III, or IV, or an international prognostic score of ≥3 on a scale of 0 to 7, with higher scores indicating increased risk), to receive either BEACOPP or ABVD, each followed by local radiotherapy when indicated. Patients with residual or progressive disease after the initial therapy were to be treated according to a state-of-the-art high-dose salvage program. The median follow-up period was 61 months. RESULTS The 7-year rate of freedom from first progression was 85% among patients who had received initial treatment with BEACOPP and 73% among those who had received initial treatment with ABVD (P=0.004), and the 7-year rate of event-free survival was 78% and 71%, respectively (P=0.15). A total of 65 patients (20 in the BEACOPP group, and 45 in the ABVD group) went on to receive the intended high-dose salvage regimen. As of the cutoff date, 3 of the 20 patients in the BEACOPP group and 15 of the 45 in the ABVD group who had had progressive disease or relapse after the initial therapy were alive and free of disease. After completion of the overall planned treatment, including salvage therapy, the 7-year rate of freedom from a second progression was 88% in the BEACOPP group and 82% in the ABVD group (P=0.12), and the 7-year rate of overall survival was 89% and 84%, respectively (P=0.39). Severe adverse events occurred more frequently in the BEACOPP group than in the ABVD group. CONCLUSIONS Treatment with BEACOPP, as compared with ABVD, resulted in better initial tumor control, but the long-term clinical outcome did not differ significantly between the two regimens. (Funded by Fondazione Michelangelo; ClinicalTrials.gov number, NCT01251107.).

Prospective, multicenter randomized GITMO/IIL trial comparing intensive (R-HDS) versus conventional (CHOP-R) chemoimmunotherapy in high-risk follicular lymphoma at diagnosis: the superior disease control of R-HDS does not translate into an overall survival advantage

In this randomized multicenter study of 136 patients, 6 courses of CHOP (cyclo-phosphamide/doxorubicin/vincristine/prednisone) followed by rituximab (CHOP-R) were compared with rituximab-supplemented high-dose sequential chemotherapy with autografting (R-HDS) to assess the value of intensified chemo-therapy as a first-line treatment for high-risk follicular lymphoma (FL) after the introduction of monoclonal antibodies. The analysis was intention to treat with event-free survival (EFS) as the primary endpoint. Complete remission (CR) was 62% with CHOP-R and 85% with R-HDS (P < .001). At a median follow-up (MFU) of 51 months, the 4-year EFS was 28% and 61%, respectively (P < .001), with no difference in overall survival (OS). Molecular remission (MR) was achieved in 44% of CHOP-R and 80% of R-HDS patients (P < .001), and was the strongest independent outcome predictor. Patients relapsing after CHOP-R underwent salvage R-HDS in 71% of cases. Salvage R-HDS had an 85% CR rate and a 68% 3-year EFS (MFU, 30 months). We conclude that (1) achieving MR is critical for effective disease control, regardless of which treatment is used; (2) R-HDS ensures superior disease control and molecular outcome than CHOP-R, but no OS improvement; and (3) CHOP-R failures have a good outcome after salvage R-HDS, suggesting that relapsed/refractory FL could be the most appropriate setting for R-HDS-like treatments. This trial was registered at www.clinicaltrials.gov as no. NCT00435955.

Simple diagnostic assay for hairy cell leukaemia by immunocytochemical detection of annexin A1 (ANXA1)

A marker capable of distinguishing with certainty between hairy cell leukaemia and other B-cell malignant disease would be of great diagnostic value. Through gene expression profiling, annexin A1 (ANXA1) has been identified as a gene that is upregulated in hairy cell leukaemia. We did immunostaining of 500 B-cell tumours with a specific anti-ANXA1 monoclonal antibody and showed that ANXA1 protein expression is specific to hairy cell leukaemia. Immunocytochemical detection of ANXA1 represents a simple, inexpensive, highly sensitive and specific (100%) assay for diagnosis of hairy cell leukaemia. This assay will be especially useful in distinguishing hairy cell leukaemia from splenic lymphoma with villous lymphocytes and variant hairy cell leukaemia, both of which usually respond poorly to treatments that are effective in hairy cell leukaemia.

Gene expression profiling of hairy cell leukemia reveals a phenotype related to memory B cells with altered expression of chemokine and adhesion receptors

Hairy cell leukemia (HCL) is a chronic B cell malignancy characterized by the diffuse infiltration of bone marrow and spleen by cells displaying a typical “hairy” morphology. However, the nature of the HCL phenotype and its relationship to normal B cells and to other lymphoma subtypes remains unclear. Using gene expression profiling, we show here that HCL displays a homogeneous pattern of gene expression, which is clearly distinct from that of other B cell non-Hodgkin lymphomas. Comparison with the gene expression profiles of purified normal B cell subpopulations, including germinal center (GC), pre-GC (naive), and post-GC (memory) B cells, shows that HCL cells are more related to memory cells, suggesting a derivation from this B cell population. Notably, when compared with memory cells, HCL cells displayed a remarkable conservation in proliferation, apoptosis, and DNA metabolism programs, whereas they appeared significantly altered in the expression of genes controlling cell adhesion and response to chemokines. Finally, these analyses have identified several genes that are specifically expressed in HCL and whose expression was confirmed at the protein level by immunocytochemical analysis of primary HCL cases. These results have biological implications relevant to the pathogenesis of this malignancy as well as clinical implications for its diagnosis and therapy.

R-CVP versus R-CHOP versus R-FM for the initial treatment of patients with advanced-stage follicular lymphoma: results of the FOLL05 trial conducted by the Fondazione Italiana Linfomi.

PURPOSE Although rituximab (R) is commonly used for patients with advanced follicular lymphoma (FL) requiring treatment, the optimal associated chemotherapy regimen has yet to be clarified. PATIENTS AND METHODS We conducted an open-label, multicenter, randomized trial among adult patients with previously untreated stages II to IV FL to compare efficacy of eight doses of R associated with eight cycles of cyclophosphamide, vincristine, and prednisone (CVP) or six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or six cycles of fludarabine and mitoxantrone (FM). The principal end point of the study was time to treatment failure (TTF). RESULTS There were 534 patients enrolled onto the study. Overall response rates were 88%, 93%, and 91% for R-CVP, R-CHOP, and R-FM, respectively (P=.247). After a median follow-up of 34 months, 3-year TTFs were 46%, 62%, and 59% for the respective treatment groups (R-CHOP v R-CVP, P=.003; R-FM v R-CVP, P=.006; R-FM v R-CHOP, P=.763). Three-year progression-free survival (PFS) rates were 52%, 68%, and 63% (overall P=.011), respectively, and 3-year overall survival was 95% for the whole series. R-FM resulted in higher rates of grade 3 to 4 neutropenia (64%) compared with R-CVP (28%) and R-CHOP (50%; P< .001). Overall, 23 second malignancies were registered during follow-up: four in R-CVP, five in R-CHOP, and 14 in R-FM. CONCLUSION In this study, R-CHOP and R-FM were superior to R-CVP in terms of 3-year TTF and PFS. In addition, R-CHOP had a better risk-benefit ratio compared with R-FM.

Fludarabine Plus Mitoxantrone With and Without Rituximab Versus CHOP With and Without Rituximab As Front-Line Treatment for Patients With Follicular Lymphoma

PURPOSE Promising new therapeutic options for follicular lymphoma (FL) include fludarabine plus mitoxantrone (FM) and the mouse/human anti-CD20 antibody, rituximab. We performed a randomized comparative trial of FM with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) front-line chemotherapy with and without sequential rituximab. PATIENTS AND METHODS All previously untreated CD20(+) FL patients presenting in 15 Italian cooperative institutions from October 1999 were randomly allocated to FM or CHOP. Following clinical or molecular restaging, patients in complete remission (CR) with bcl-2/IgH negativity (CR(-)) received no further treatment; those in CR with bcl-2/IgH positivity (CR(+)) received rituximab, as did those in partial remission (PR) with bcl-2/IgH negativity (PR(-)) or positivity (PR(+)); nonresponders (NR subgroup) were off study. RESULTS After chemotherapy, the FM arm achieved higher rates of CR (68% [49 of 72 patients] v 42% [29 of 68 patients]; P =.003) and CR(-) (39% [28 of 72 patients] v 13 of 68 patients [19%]; P =.001). Rituximab elicited CR(-) in 55 of 95 treated patients (58%). The final CR(-) rate was higher in the FM arm (71% [51 of 72 patients] v 51% [35 of 68 patients]; P =.01). However, with a median follow-up of 19 months (range, 9 to 37 months), no statistically significant difference was found among the various study arms in terms of both progression-free (PFS) and overall survival (OS). CONCLUSION These results indicate that FM is superior to CHOP for front-line treatment of FL and that rituximab is an effective sequential treatment option. However, they also confirm that this superiority is unlikely to translate into either better PFS or OS.

Simple genetic diagnosis of hairy cell leukemia by sensitive detection of the BRAF-V600E mutation

Hairy cell leukemia (HCL) is a distinct clinicopathologic entity that responds well to purine analogs but is sometimes difficult to differentiate from HCL-like disorders (e.g., splenic marginal zone lymphoma and HCL variant). We recently identified the BRAF-V600E mutation as the disease-defining genetic event in HCL. In this study, we describe a new, simple, and inexpensive test for genetics-based diagnosis of HCL in whole-blood samples that detects BRAF-V600E through a sensitive allele-specific PCR qualitative assay followed by agarose-gel electrophoresis. This approach detected BRAF-V600E in all 123 leukemic HCL samples investigated containing as few as 0.1% leukemic cells. BRAF-V600E was detected at different time points during the disease course, even after therapy, pointing to its pivotal role in HCL pathogenesis and maintenance of the leukemic clone. Conversely, 115 non-HCL chronic B-cell neoplasms, including 79 HCL-like disorders, were invariably negative for BRAF-V600E. This molecular assay is a powerful tool for improving the diagnostic accuracy in HCL.

The predictive role of interim positron emission tomography for Hodgkin lymphoma treatment outcome is confirmed using the interpretation criteria of the Deauville five-point scale

A retrospective, international, multicenter study was undertaken to assess: (i) the prognostic role of ‘interim’ positron emission tomography performed during treatment with doxorubicin, bleomycin, vinblastine and dacarbazine in patients with Hodgkin lymphoma; and (ii) the reproducibility of the Deauville five-point scale for the interpretation of interim positron emission tomography scan. Two hundred and sixty patients with newly diagnosed Hodgkin lymphoma were enrolled. Fifty-three patients with early unfavorable and 207 with advanced-stage disease were treated with doxorubicin, bleomycin, vinblastine and dacarbazine ± involved-field or consolidation radiotherapy. Positron emission tomography scan was performed at baseline and after two cycles of chemotherapy. Treatment was not changed according to the results of the interim scan. An international panel of six expert reviewers independently reported the scans using the Deauville five-point scale, blinded to treatment outcome. Forty-five scans were scored as positive (17.3%) and 215 (82.7%) as negative. After a median follow up of 37.0 (2–110) months, 252 patients are alive and eight have died. The 3-year progression-free survival rate was 83% for the whole study population, 28% for patients with interim positive scans and 95% for patients with interim negative scans (P<0.0001). The sensitivity, specificity, and negative and positive predictive values of interim positron emission tomography scans for predicting treatment outcome were 0.73, 0.94, 0.94 and 0.73, respectively. Binary concordance amongst reviewers was good (Cohen’s kappa 0.69–0.84). In conclusion, the prognostic role and validity of the Deauville five-point scale for interpretation of interim positron emission tomography scans have been confirmed by the present study.