Inhibition of bromodomain and extra-terminal proteins increases sensitivity to venetoclax in chronic lymphocytic leukaemia.

The development of drugs able to target BTK, PI3k-delta and BCL2 has dramatically improved chronic lymphocytic leukaemia (CLL) therapies. However, drug resistance to these therapies has already been reported due to non-recurrent changes in oncogenic pathways and genes expression signatures. In this study, we investigated the cooperative role of the BCL2 inhibitor venetoclax and the BRD4 inhibitor JQ1. In particular, we found that JQ1 shows additional activity with venetoclax, in CLL cell lines and in ex vivo isolated primary CD19+ lymphocytes, arguing in favour of combination strategies. Lastly, JQ1 is also effective in venetoclax-resistant CLL cell lines. Together, our findings indicated that the BET inhibitor JQ1 could be a promising therapy in CLL, both as first-line therapy in combination with venetoclax and as second-line therapy, after the emergence of venetoclax-resistant clones.

Prolonged survival in the absence of disease-recurrence in advanced-stage follicular lymphoma following chemo-immunotherapy: 13-year update of the prospective, multicenter randomized GITMO-IIL trial.

A prospective trial conducted in the period 2000-2005 showed no survival advantage for high-dose chemotherapy with rituximab and autograft (R-HDS) versus conventional chemotherapy with rituximab (CHOP-R) as first-line therapy in 134 high-risk follicular lymphoma patients aged <60 years. The study has been updated at the 13-year median follow up. As of February 2017, 88 (66%) patients were alive, with overall survival of 66.4% at 13 years, without a significant difference between R-HDS (64.5%) and CHOP-R (68.5%). To date, 46 patients have died, mainly because of disease progression (47.8% of all deaths), secondary malignancies (3 solid tumor, 9 myelodysplasia/acute leukemia; 26.1% of all deaths), and other toxicities (21.7% of all deaths). Complete remission was documented in 98 (73.1%) patients and associated with overall survival, with 13-year estimates of 77.0% and 36.8% for complete remission versus no-complete remission, respectively. Molecular remission was documented in 39 (65%) out of 60 evaluable patients and associated with improved survival. In multivariate analysis, complete remission achievement had the strongest effect on survival (P<0.001), along with younger age (P=0.002) and female sex (P=0.013). Overall, 50 patients (37.3%) survived with no disease recurrence (18 CHOP-R, 32 R-HDS). This follow up is the longest reported on follicular lymphoma treated upfront with rituximab-chemotherapy and demonstrates an unprecedented improvement in survival compared to the pre-rituximab era, regardless of the use of intensified or conventional treatment. Complete remission was the most important factor for prolonged survival and a high proportion of patients had prolonged survival in their first remission, raising the issue of curability in follicular lymphoma. (Registered at clinicaltrials.gov identifier: 00435955).

Diffusion-weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient.

PURPOSE: To compare perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum. MATERIALS AND METHODS: Seventy-six subjects were divided into a "benign conditions" group (A, n = 44) and a "malignancies" group (B, n = 32), based on histological findings. diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at b of 0/150/800 sec/mm(2) . The ADCs were obtained on an ADC map by including (perfusion-sensitive = ADCb0-800 ) and excluding (perfusion-free = ADCb150-800 ) the b = 0 sec/mm(2) . The Mann-Whitney U-test was used to detect differences in ADCb0-800 compared with ADCb150-800 values between all cases, benign conditions, and malignancies. The same test was used to evaluate differences in ADCs between the two groups for each type of measurement (ADCb0-800 and ADCb150-800 ), and receiver-operating characteristic (ROC) curves were obtained to evaluate discrimination abilities with comparison of areas-under-ROC-curves (AUROC). Optimal cutpoints for discrimination between groups were determined by the Youden-Index with computation of accuracy. RESULTS: The median ADCb0-800 was significantly greater compared with ADCb150-800 for all cases (P = 0.0014), benign conditions (P = 0.0412), and malignancies (P = 0.0001). The median percentage of increase was 5.30% for group-A and 22.39% for group-B (P < 0.0001). AUROC of ADC in discriminating between groups was significantly greater for ADCb150-800 (0.932) compared with ADCb0-800 (0.831) (P = 0.001). The optimal cutpoint for distinction between groups was 1.52 × 10(-3) mm(2) /sec (sensitivity = 93.7%, specificity = 88.6%, accuracy = 90.8%) for ADCb150-800 and 1.75 × 10(-3) mm(2) /sec (sensitivity = 75.0%, specificity = 79.5%, accuracy = 77.6%) for ADCb0-800 . CONCLUSION: The use of perfusion-free ADC measurements significantly improves diagnostic accuracy of DW-MRI in differentiating benign conditions from malignancies of the anterior mediastinum. J. Magn. Reson. Imaging 2016;44:758-769.

A Radiation-Free Approach Based on the Whole-Body MRI Has Shown a High Level of Accuracy in the Follow-Up of Lymphoma Patients-A Single Center Retrospective Study.

Background: Recurrence, even after years from the last treatment, characterizes lymphoproliferative disorders. Therefore, patients in complete remission from the disease should be followed up with periodic clinical checks. There is not a consensus on the role of imaging for this aim, because the radiological techniques used at the time of diagnosis expose patients to a risk of ionizing radiation damage. Whole-body magnetic resonance imaging with diffusion-weighted imaging (WB-MRI-DWI) has given similar results to gold standard techniques in detecting lymphoma in the involved sites without ionizing radiation. In this retrospective real-life study, we aimed to assess the accuracy of WB-MRI-DWI during follow-ups of lymphoma patients in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Methods: Lymphoma patients who were subject to at least one WB-MRI-DWI during follow-up between February 2010 and February 2022 were enrolled. Results: Based on our investigation, the calculated sensitivity of WB-MRI-DWI was 100% (95% CI: 99.4-100.0), the specificity was 98.6% (95% CI: 97.4-99.3), PPV was 79% (95% CI: 75.9-81.9), and NPV was 100% (95% CI: 99.4-100.0). Conclusions: Despite the possibility of poor patient compliance and the identification of false positives, WB-MRI-DWI examination demonstrated an excellent sensitivity in ruling out the disease relapse.

Low-dose radiotherapy for extranodal marginal zone B lymphoma of the lip: Case report and literature review.

Non-Hodgkin lymphoma (NHL) of the lip is extremely rare. It is usually indolent and in early stages a local approach is often indicated. We present a case report of a patient with extranodal NHL of the lip treated with chemotherapy and low-dose radiation treatment (RT). The patient was affected by B-cell NHL of the marginal zone, Stage IAE. After a few months of observation with progressive disease, the patient was submitted to two cycles of chemotherapy with no response. Therefore, he was treated with very low-dose RT consisting of two fractions of 2 Gy. Complete response was observed and after 1-year follow-up, persistent complete response was recorded. In cases of localized disease, especially in patients with comorbidities of poor performance status (PS), low-dose RT can be an appropriate approach with excellent outcomes in terms of effectiveness and low risk of toxicity.

The neutrophil to lymphocyte ratio (NLR) and the presence of large nodal mass are independent predictors of early response: A subanalysis of the prospective phase II PET-2-adapted HD0607 trial.

BACKGROUND: The neutrophil to lymphocyte ratio (NLR) and the lymphocyte to monocyte ratio (LMR) can reflect both the myeloid dysfunction and T-cell immune suppression and have prognostic significance. METHODS: In 771 newly diagnosed advanced-stage Hodgkin Lymphoma (HL) patients we evaluated the baseline values of NLR and LMR as predictors of clinical outcome. According to the multicenter prospective phase II GITIL-HD0607 trial, all patients received two ABVD courses and if PET-2 negative received four additional ABVD cycles while if PET-2-positive patients were randomized to either BEACOPP escalated (Be) plus BEACOPP baseline (Bb) (4 + 4 courses) or Be + Bb (4 + 4) and Rituximab. PET scans were centrally reviewed by an expert panel by Blinded Independent Central Review. RESULTS: Higher NLR and lower LMR were associated with a PET-2 positivity and failure to achieve long-term disease control, respectively. By univariate and multivariate analysis, large nodal mass (>7 cm), IPS ≥ 3, NLR > 6 were strong independent predictors of early PET-2 response after ABVD. Only NLR > 6 and IPS ≥ 3 were strong independent predictors of outcome at diagnosis; however, when PET-2 status was added, only PET-2-positive status and IPS ≥ 3 were independent predictors of PFS. Focusing on PET-2-negative patients, those with NLR > 6 had an inferior 3-year PFS compared to patients with NLR ≤ 6 (84% vs 89% months, P = .03). CONCLUSION: In advanced-stage HL patients treated with a PET-2-driven strategy, IPS ≥ 3 and NLR > 6 are independent predictors of outcome at diagnosis while the presence of large nodal mass, IPS ≥ 3, and NLR > 6 at diagnosis are independent predictors of early ABVD response.

Early Chemotherapy Intensification With Escalated BEACOPP in Patients With Advanced-Stage Hodgkin Lymphoma With a Positive Interim Positron Emission Tomography/Computed Tomography Scan After Two ABVD Cycles: Long-Term Results of the GITIL/FIL HD 0607 Trial.

Purpose To investigate the progression-free survival (PFS) of patients with advanced Hodgkin lymphoma (HL) after a risk-adapted treatment strategy that was based on a positive positron emission tomography scan performed after two doxorubicin, vinblastine, vincristine, and dacarbazine (ABVD) cycles (PET2). Patients and Methods Patients with advanced-stage (IIB to IVB) HL were consecutively enrolled. After two ABVD cycles, PET2 was performed and centrally reviewed according to the Deauville five-point scale. Patients with a positive PET2 were randomly assigned to four cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) followed by four cycles of standard BEACOPP with or without rituximab. Patients with a negative PET2 continued ABVD, and those with a large nodal mass at diagnosis (≥ 5 cm) in complete remission with a negative PET at the end of chemotherapy were randomly assigned to radiotherapy or no further treatment. The primary end point was 3-year PFS. Results Of 782 enrolled patients, 150 (19%) had a positive and 630 (81%) a negative PET2. The 3-year PFS of all patients was 82%. The 3-year PFS of those with a positive and negative PET2 was 60% and 87%, respectively ( P < .001). The 3-year PFS of patients with a positive PET2 assigned to BEACOPP with or without rituximab was 63% versus 57% ( P = .53). In 296 patients with both interim and post-ABVD-negative PET who had a large nodal mass at diagnosis, radiotherapy was randomly added after chemotherapy without a significant PFS improvement (97% v 93%, respectively; P = .29). The 3-year overall survival of all 782 patients was 97% (99% and 89% for PET2 negative and positive, respectively). Conclusion The PET-driven switch from ABVD to escalated BEACOPP is feasible and effective in high-risk patients with advanced-stage HL.

Potential Benefit of Involved-Field Radiotherapy for Patients With Relapsed-Refractory Hodgkin's Lymphoma With Incomplete Response Before Autologous Stem Cell Transplantation.

INTRODUCTION: We investigated for a possible role for peritransplantation involved-field radiotherapy (IFRT) by comparing patients who received IFRT before after autologous stem cell transplantation (ASCT) and patients who received salvage chemotherapy (CT) alone. PATIENTS AND METHODS: We retrospectively evaluated 73 consecutive patients with Hodgkin lymphoma treated with ASCT between 2003 and 2014. Twenty-one patients (28.8%) received peritransplantation radiotherapy. A Cox regression analysis (multivariate analysis; MVA) was performed to evaluate the prognostic role of any risk factor. Overall survival (OS) and progression-free survival (PFS) were calculated from the date of ASCT. Response to CT and ASCT were evaluated with positron emission tomography (PET) scan. RESULTS: Median follow-up was 41 months (range, 1-136 months). Overall, no significant difference appeared between patients who received IFRT and patients treated with CT alone; however, patients who were treated with IFRT had worse prognostic factors. In the MVA, advanced stage at relapse and persistent disease before ASCT (evident on PET scan [PET+]) were related to worse PFS and OS. In patients with limited stage disease at relapse and PET+, peritransplantation radiotherapy showed higher 3-year OS rates (91.7% vs. 62.3%) and PFS rates (67.5% vs. 50%) compared with patients treated with CT alone, although this difference was not significant (P = .14 and P = .22, respectively). CONCLUSION: IFRT used before or after ASCT might partially compensate for worse prognostic factors among the overall population; subgroup analysis showed a trend for survival benefit at 3 years in patients with limited stage disease at relapse and PET+ before ASCT.

Therapeutic inhibition of USP7-PTEN network in chronic lymphocytic leukemia: a strategy to overcome TP53 mutated/deleted clones.

Chronic Lymphocytic Leukemia (CLL) is a lymphoproliferative disorder with either indolent or aggressive clinical course. Current treatment regiments have significantly improved the overall outcomes even if higher risk subgroups - those harboring TP53 mutations or deletions of the short arm of chromosome 17 (del17p) - remain highly challenging. In the present work, we identified USP7, a known de-ubiquitinase with multiple roles in cellular homeostasis, as a potential therapeutic target in CLL. We demonstrated that in primary CLL samples and in CLL cell lines USP7 is: i) over-expressed through a mechanism involving miR-338-3p and miR-181b deregulation; ii) functionally activated by Casein Kinase 2 (CK2), an upstream interactor known to be deregulated in CLL; iii) effectively targeted by the USP7 inhibitor P5091. Treatment of primary CLL samples and cell lines with P5091 induces cell growth arrest and apoptosis, through the restoration of PTEN nuclear pool, both in TP53-wild type and -null environment. Importantly, PTEN acts as the main tumor suppressive mediator along the USP7-PTEN axis in a p53 dispensable manner. In conclusion, we propose USP7 as a new druggable target in CLL.

Addition of Rituximab to Involved-Field Radiation Therapy Prolongs Progression-free Survival in Stage I-II Follicular Lymphoma: Results of a Multicenter Study.

PURPOSE: Rituximab (Rit) therapy added to involved-field radiation therapy (RT) has been proposed as an effective treatment for stage I-II follicular lymphoma (FL). The results of an observational multicenter study on the Rit-RT combination in limited-stage FL are here reported. METHODS AND MATERIALS: Data have been collected from 2 consecutive cohorts of 94 patients with stage I-II FL treated between 1985 and 2011 at 5 Italian institutions. All patients had grade 1-3a FL, a median age of 54 years (range: 25-82). The first 51 patients received RT alone (control group), while the subsequent series of 43 patients received 4 rituximab courses (375 mg/m(2), days 1, 8, 15, 22) before RT (Rit-RT). Molecular disease was evaluated by nested bcl-2/IgH PCR or clonal IgH rearrangement was available in 33 Rit-RT patients. RESULTS: At a median follow-up of 10.9 years (range: 1.8-22.9), the 10-year progression-free survival (PFS) and overall survival (OS) projections for the whole cohort were 57% and 87.5%, respectively. The 10-year PFS was significantly longer (P<.05) in the Rit-RT group (64.6%) compared to RT alone (50.7%), whereas the 10-year OS projections were not significantly different. On bivariate analysis controlling for stage, there was only a trend toward improved PFS for Rit-RT (HR, 0.55; P=.081). Follicular lymphoma international prognostic index and age were associated with OS but not with PFS on Cox regression analysis. Bone marrow molecular analysis showing PCR positivity at diagnosis was strongly associated with relapse risk upon univariate and multivariate analysis. CONCLUSIONS: This multicenter observational study suggests a potential benefit of adding rituximab to radiation therapy for stage I-II FL. The results of the currently ongoing randomized studies are required to confirm these results. The study underlines the importance of molecular disease monitoring also for patient with limited-stage disease.

High dose sequential chemotherapy with autologous transplantation versus dose-dense chemotherapy MegaCEOP as first line treatment in poor-prognosis diffuse large cell lymphoma: an "Intergruppo Italiano Linfomi" randomized trial.

BACKGROUND AND OBJECTIVES: Poor prognosis diffuse large cell lymphoma (DLCL) responds poorly to standard chemotherapy. Randomized studies comparing high-dose chemotherapy with autologous stem-cell transplantation (ASCT) against standard chemotherapy have produced conflicting results. Dose-dense chemotherapy with granulocyte colony-stimulating factor (G-CSF) support seems to hold promise. The purpose of this multicenter, randomized trial was to compare failure-free and overall survival in patients with poor prognosis DLCL treated with high-dose sequential (HDS) chemotherapy followed by ASCT or an outpatient dose-dense chemotherapy regimen (MegaCEOP). DESIGN AND METHODS: Between 1996 and 2001, 130 DLCL patients, aged < or = 60 years, with intermediate-high or high-risk disease, according to the International Prognostic Index score, and/or bone marrow involvement were enrolled. Sixty were randomized to HDS chemotherapy plus high-dose mitoxantrone and melphalan with ASCT (arm A) and 66 to the MegaCEOP regimen (6-8 courses of an escalated dose of cyclophosphamide and epirubicin plus vincristine and prednisone with G-CSF every 2-weeks) (arm B); 4 patients were considered ineligible. RESULTS: The complete remission rate was 59% in arm A and 70% in arm B (p = 0.18). After a median follow-up of 78 months, the 6-year failure-free survival was 45% in arm A and 48% in arm B (hazard ratio = 1.15, 95% confidence intervals = 0.72-1.84, p = 0.56). The 5-year overall survival was 49% in arm A and 63% in arm B (hazard ratio = 1.67, 95% confidence interval = 0.98-2.85, p = 0.06). Two cases of secondary acute myeloid leukemia were observed after treatment in group A. INTERPRETATION AND CONCLUSIONS: HDS and ASCT as initial therapy for patients with poor-prognosis DLCL does not provide a benefit over that of outpatient dose-dense MegaCEOP chemotherapy.

Interim positron emission tomography and clinical outcome in patients with early stage Hodgkin lymphoma treated with combined modality therapy.

The aim of the study was to investigate whether interim positron emission tomography (iPET) is prognostic in a cohort of patients with early stage Hodgkin lymphoma (HL) homogeneously treated with 3-4 cycles of ABVD (adriamycin, bleomycin, vinblastine and dacarbazine) followed by 30 Gy involved field radiotherapy. Eighty patients were selected (stage I-IIA HL, availability of iPET, minimum follow-up of 12 months), and after central review, 70 were judged negative (iPET-: 87.5%) and 10 positive (iPET+: 12.5%). The two groups were then analyzed for response, progression-free survival (PFS) and overall survival (OS). Only one out of 70 iPET- patients relapsed, with 69 in continuous complete remission (CCR). All 10 iPET + patients achieved a complete response and maintained persistent CCR at follow-up. The 3-year PFS and OS were, respectively, 97% and 98.4% for iPET- and 100% and 100% for iPET+ (p = 0.63). iPET positivity does not seem to be a significant prognostic factor, and change in therapeutic strategy on the basis of iPET does not appear currently advisable outside clinical trials.

Rituximab maintenance compared with observation after brief first-line R-FND chemoimmunotherapy with rituximab consolidation in patients age older than 60 years with advanced follicular lymphoma: a phase III randomized study by the Fondazione Italiana Linfomi.

PURPOSE: To evaluate the efficacy of rituximab maintenance in 60- to 75-year-old patients with advanced follicular lymphoma responding to brief first-line chemoimmunotherapy followed by rituximab consolidation. PATIENTS AND METHODS: A total of 234 treatment-naive 60- to 75-year-old patients began chemoimmunotherapy with four monthly courses of rituximab, fludarabine, mitoxantrone, and dexamethasone (R-FND) followed by four weekly cycles of rituximab consolidation. Of these, 210 patients completed the planned treatment, and 202 responders were randomly assigned to rituximab maintenance (arm A) for 8 months, once every 2 months for a total of four doses, or to observation (arm B). RESULTS: Median ages in arms A and B were 66 and 65 years, respectively. After induction and consolidation therapy, the overall response rate was 86%, with 69% complete remissions (CR). After a 42-month median follow-up from diagnosis, 3-year progression-free survival (PFS; the primary end point) and overall survival (OS) were 66% (95% CI, 59% to 72%) and 89% (95% CI, 85% to 93%), respectively. After randomization, 2-year PFS was 81% for rituximab maintenance versus 69% for observation, with a hazard ratio of 0.74 (95% CI, 0.45 to 1.21; P = .226), although this was not statistically significant. No differences between the two arms were detected for OS. Overall, the regimen was well-tolerated. The most frequent grade 3 to 4 toxicity was neutropenia (25% of treatment courses), with 13 infections. Two toxic deaths (0.8%) occurred during induction treatment. CONCLUSION: A brief R-FND induction plus rituximab consolidation achieved excellent results with high CR and PFS rates, supporting the feasibility of this regimen in patients older than 60 years. A short rituximab maintenance did not achieve a statistically significant PFS improvement over observation.

Risk factors for the development of secondary malignancy after high-dose chemotherapy and autograft, with or without rituximab: a 20-year retrospective follow-up study in patients with lymphoma.

PURPOSE: High-dose chemotherapy with peripheral blood progenitor cell (PBPC) autograft is effective in high-risk lymphoma, particularly with the addition of rituximab; however, it is associated with risk of secondary malignancy. These issues have been addressed in a series of 1,347 patients with lymphoma treated with a high-dose sequential (HDS) program. PATIENTS AND METHODS: A total of 1,024 patients with B-cell lymphoma, 234 patients with Hodgkin's lymphoma, and 89 patients with T-cell lymphoma were treated with HDS between 1985 and 2005 at 11 Gruppo Italiano Terapie Innovative Linfomi centers. HDS was given as salvage treatment to 707 patients (52%); 655 patients (49%) received a modified HDS, with high-dose cytarabine and two consecutive PBPC harvests. Rituximab-supplemented HDS was given to 523 patients (39%). RESULTS: At a median follow-up of 7 years, the median overall survival (OS) was 16.2 years; in B-cell lymphoma the OS was significantly superior with rituximab HDS compared to HDS alone. The cumulative incidence at 5 and 10 years of secondary myelodysplasia/acute leukemia (sMDS/AL) were 3.09% and 4.52%, respectively, that of solid tumors were 2.54% and 6.79%, respectively. Factors associated with sMDS/AL were male sex and use of the second harvest PBPC for the graft; factors found to be associated with solid tumor were advanced age, post-HDS radiotherapy, and rituximab addition to HDS. Despite the increased risk of solid tumors, rituximab addition to HDS was still associated with survival advantages. CONCLUSION: This analysis has relevant implications for the design and use of intensive chemoimmunotherapy with autograft. In addition, it offers useful insights toward the understanding and prevention of tumor development.

CT findings in primary pulmonary lymphomas.

PURPOSE: To describe the CT findings of pathologically confirmed primary pulmonary lymphomas. MATERIALS AND METHODS: The CT examinations of 11 patients with pathologically proven primary pulmonary lymphoma (9 BALT lymphomas and 2 non-BALT lymphomas) were retrospectively reviewed by three radiologists. Evaluated findings included morphology (consolidation, mass, nodule), number and distribution of lesions. Other CT findings such as air bronchogram, lymphadenopathy, atelectasis and pleural effusion were also assessed. RESULTS: Pulmonary lesions were depicted as airspace consolidation (pneumonia-like) in 5 patients (45%), tumour-like rounded opacity in 4 (36%), and nodules in 4 (36%). Multiple and bilateral lung lesions were seen in 3 patients (27%). Air bronchogram was present in 7 patients (63%), lymphadenopathy in 3 (27%), atelectasis in 4 (36%) and pleural effusion in only 1 (9%). CONCLUSIONS: Our results agree with previous studies regarding lesion patterns and their relative frequency. A smaller number of nodules and multiple lesions were found compared with some previous studies. The most frequent pattern was airspace consolidation.

Long-term remission in mantle cell lymphoma following high-dose sequential chemotherapy and in vivo rituximab-purged stem cell autografting (R-HDS regimen).

Mantle cell lymphoma (MCL) is rarely cured with standard-dose chemotherapy. From January 1997 to February 2000, 28 previously untreated advanced-stage MCL patients younger than 61 years of age were treated at 9 Italian hematologic departments with 3 cycles of standard-dose debulking chemotherapy followed by a high-dose rituximab-supplemented sequence (R-HDS) including intravenous administration of high-dose cyclophosphamide, high-dose cytarabine, high-dose melphalan, and high-dose mitoxantrone plus melphalan. Study end points included toxicity, clinical and molecular response rates, long-term event-free survival (EFS), and overall survival (OS) rates, as well as the ability to harvest tumor-free peripheral blood stem cells. Optimal amounts of polymerase chain reaction-negative (PCR-negative) CD34+ cells were collected from all 20 informative patients. One patient died of toxicity. All 27 patients assessable for response achieved a complete response (CR), of which 24 remain in continuous complete remission (CCR) after a median follow-up of 35 months. Three patients had transient evidence of PCR-detectable disease in the bone marrow. The OS and EFS rates at 54 months were 89% and 79%, respectively. These results compare with the 42% OS rate and the 18% EFS rate observed in 35 age-matched historic controls treated with standard-dose chemotherapy at the participating centers. The use of rituximab in combination with high-dose chemotherapy represents a very effective in vivo purging method. The R-HDS regimen can be safely applied in a multicenter hematology setting and leads to long-term EFS and OS in the majority of patients with an otherwise incurable disease.