Adjuvant rituximab causes prolonged hypogammaglobulinaemia following autologous stem cell transplant for non-Hodgkin's lymphoma

Rituximab is an anti-CD20 monoclonal antibody that has efficacy in B-cell non-Hodgkin's lymphoma (NHL). Adjuvant immunotherapy with rituximab may reduce relapse rates for high-risk B-cell NHL following high-dose chemotherapy with autologous stem cell transplantation (SCT). However, the potential adverse effects of rituximab on immune reconstitution following SCT are not fully characterized. We performed a retrospective analysis of immunoglobulin (Ig) levels and peripheral blood neutrophil counts in 11 patients who received adjuvant rituximab following autologous SCT for B-cell NHL. Results were compared to a contemporaneous group of 24 patients who received an identical conditioning regimen and autologous SCT for lymphoma, but no adjuvant rituximab. Adjuvant rituximab was associated with a significantly increased incidence of hypogammaglobulinaemia between 12 and 24 months post-SCT, but not neutropenia. Despite suppression of Igs, there were no late or atypical infective complications attributable to rituximab.     

B cells in rheumatoid arthritis: from hypothesis to the clinic

Rituximab (MabThera/Rituxan) is a therapeutic monoclonal antibody against CD20, an antigen expressed by B cells but not B-cell progenitor or plasma cells. It is currently approved for the treatment of relapsed or refractory B-cell non-Hodgkin's lymphoma (NHL) and is well tolerated and efficacious. A small open-label study (conducted by Edwards and Cambridge) indicated that selective depletion of B cells using rituximab led to sustained benefits for patients with active rheumatoid arthritis. A 24-week, double-blind, randomized controlled trial was carried out to confirm these initial observations. In total, 161 patients with active rheumatoid arthritis were randomized to one of four treatment groups: rituximab monotherapy; rituximab plus methotrexate (R+MTX); rituximab plus cyclophosphamide (R+CTX); or methotrexate alone (MTX). Rituximab was administered as two 1000 mg infusions on days 1 and 15. An analysis at 24 weeks showed that the proportion of patients achieving an ACR20 response was significantly greater (P < or = 0.025 for all three comparisons) in all the rituximab groups compared with the MTX control group (rituximab alone, 65%; R+CTX, 76%; R+MTX, 73%; MTX alone, 38%). Both ACR50 (43 vs 13%; P = 0.005) and ACR70 (23 vs 5%; P = 0.048) responses were also significantly higher for the R+MTX group compared with the MTX group. The rituximab groups showed no significant safety differences compared with the MTX arm. The majority of adverse events were of mild to moderate intensity. Rituximab is a novel targeted therapy for the treatment of rheumatoid arthritis and it appears to be highly effective, safe and well tolerated.     

Effect of rituximab on peripheral blood stem cell mobilization and engraftment kinetics in non-Hodgkin's lymphoma patients

Rituximab is used for in vivo tumor cell purging for non-Hodgkin's lymphoma (NHL) patients prior to autologous peripheral blood stem cell transplantation (PBSCT). However, its effects on PBSC mobilization and function are poorly understood. We compared the mobilization characteristics and engraftment kinetics of 13 NHL patients receiving and 34 NHL patients not receiving rituximab 6 months before PBSC mobilization. In the rituximab group, there was a significantly longer time to neutrophil engraftment (P=0.0466), a trend toward the need for BM harvest to supplement low-yield PBSC collections (31 vs 9%, P=0.08) and a significantly increased rate of bacteremia episodes (62 vs 26%, P=0.025). Median progression-free survival (PFS) and overall survival (OS) were significantly longer in the rituximab compared to the nonrituximab patients (P=0.049 and 0.042, respectively). However, patients in the nonrituximab group were at high risk for recurrence and expected to have shorter survival. Rituximab used within 6 months prior to collection may have a detrimental effect on PBSC mobilization and engraftment. However, rituximab is a major therapeutic breakthrough for NHL treatment and this negative effect may be offset by improved survival. Further studies are warranted in larger populations to determine the impact of rituximab on engraftment, PFS and OS.     

Chemotherapy combinations with monoclonal antibodies in non-Hodgkin's lymphoma

Although the use of monoclonal antibodies as single agents has had a tremendous impact on the care of patients with non-Hodgkin's lymphoma (NHL), the greatest benefit has been generated by the addition of monoclonal antibodies to conventional cytotoxic chemotherapy. Rituximab is the monoclonal antibody responsible for all clinical improvement noted to date. The addition of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy (R-CHOP regimen) improves the response rate, progression-free survival (PFS), and overall survival (OS) in diffuse large B-cell lymphoma (DLBCL). Adding rituximab to CHOP chemotherapy improves response rates and PFS in mantle cell lymphoma (MCL). Finally, the addition of rituximab to a variety of chemotherapy regimens improves the response rates, PFS, and OS in follicular lymphoma (FL). Several other (epratuzumab, bevacizumab, alemtuzumab) monoclonal antibody-chemotherapy combinations are currently under study in NHL. This review will summarize the data supporting the addition of rituximab to chemotherapy in NHL and discuss preliminary data regarding the use of other monoclonal antibodies in combination with chemotherapy.     

Improved outcome with rituximab in patients with HIV-associated multicentric Castleman disease

Although HIV-associated multicentric Castleman disease (HIV-MCD) is not classified as an AIDS-defining illness, mortality is high and progression to lymphoma occurs frequently. At present, there is no widely accepted recommendation for the treatment of HIV-MCD. In this retrospective (1998-2010), multicentric analysis of 52 histologically proven cases, outcome was analyzed with respect to the use of different MCD therapies and potential prognostic factors. After a mean follow-up of 2.26 years, 19 of 52 patients died. Median estimated overall survival (OS) was 6.2 years. Potential risk factors, such as older age, previous AIDS, or lower CD4 T cells had no impact on OS. Treatment was heterogeneous, consisting of cytostatic and/or antiviral agents, rituximab, or combinations of these modalities. There were marked differences in the outcome when patients were grouped according to MCD treatment. Patients receiving rituximab-based regimens had higher complete remission rates than patients receiving chemotherapy only. The mean estimated OS in patients receiving rituximab alone or in combination with cytostatic agents was not reached, compared with 5.1 years (P = .03). Clinical outcome and overall survival of HIV-MCD have markedly improved with rituximab-based therapies, considering rituximab-based therapies (with or without cytostatic agents) to be among the preferred first-line options in patients with HIV-MCD.     

Definition of two distinct types of AIDS-associated non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) in a human immunodeficiency virus (HIV)-infected person is an AIDS-defining condition. There is both an increased incidence of NHL and a poorer prognosis for the disease in these HIV-infected persons, compared with patients who spontaneously develop NHL. A series of 41 consecutive patients with HIV-associated NHL treated at St Vincent's Hospital, Sydney, between 1984 and September 1989 was assessed. Of these, 36 had NHL proven on biopsy and NHL was diagnosed clinically in the other five. On histologic examination 11 had high-grade malignant lymphoma, small non-cleaved cell (SNCC) type, similar to Burkitt lymphoma, 18 had high-grade lymphoma large cell immunoblastic (LCI) type, and seven could not be classified due to inadequate material for assessment. The clinical features of these two groups were compared. Those patients with LCI had advanced CD4+ immunodeficiency and poor survival (median = 6 weeks). The other group with SNCC had better preserved immune function, and longer survival (median = 18 weeks). Three patients had survived longer than 3 years all of whom had SNCC lymphoma as their first AIDS-defining illness. The clinical features and prognostic factors demonstrated in this study document heterogeneity of NHL in HIV-infected patients and should be used as a guide to treatment of these patients, by reserving more intensive treatment for those persons with better prognostic features.     

Phase II multicenter study of oblimersen sodium, a Bcl-2 antisense oligonucleotide, in combination with rituximab in patients with recurrent B-cell non-Hodgkin lymphoma

Oblimersen sodium plus rituximab was evaluated in relapsed/refractory B-cell non-Hodgkin lymphoma (NHL) patients. Oblimersen was administered as a continuous intravenous infusion at a daily dose of 3 mg/kg/d for 7 d on alternate weeks for 3 weeks. Rituximab was given at a weekly dose of 375 mg/m(2) for six doses. Patients with stable disease or objective response were allowed to receive a second course of treatment. The overall response rate (ORR) was 42% with 10 complete responses (CR) and eight partial responses (PR). Twelve (28%) patients achieved a minimal response or stable disease. Among the 20 patients with follicular lymphoma the ORR was 60% (eight CR, four PR). Three of the responders were refractory to prior treatment with rituximab, and two of the responses occurred in patients who had failed an autologous stem cell transplant. Median duration of response was 12 months. Most toxicities were low grade and reversible. In conclusion, oblimersen sodium can be safely combined with rituximab. The combination appears to be most beneficial in patients with indolent NHL and warrants further investigation in a large randomized trial.     

Re-Treatment of Relapsed Indolent B-Cell Lymphoma With Rituximab

The purpose of this study was to investigate the toxicity and the efficacy of re-treatment with rituximab, a chimeric mouse human anti-CD20 monoclonal antibody, in relapsed patients with indolent B-cell non-Hodgkin's lymphoma (NHL) who responded to rituximab in the previous phase I or phase II study. Thirteen patients with relapsed B-cell NHL, each of whom was confirmed to have Revised European-American Lymphoma Classification type II, 1-6 histology (indolent B-NHL), enrolled in this re-treatment study. All were re-treated with rituximab at 375 mg/m2 weekly for 4 consecutive weeks. Rituximab re-treatment was well tolerated with no grade 3/4 nonhematological toxicities, similar to that of the initial treatment. No patients developed detectable human anti-chimeric antibody. Partial responses were observed in 5 of 13 patients (38%; 95% confidence interval [CI], 14% to 68%); 6 patients showed stable disease and 2 showed progressive disease. Overall survival rate was 93% at 19 months of median follow-up after rituximab re-treatment. Median progression-free survival (PFS) after the re-treatment was 5.1 months (95% CI, 4.1 to 5.6 months), and the median PFS after the initial treatment was 8.2 months (95%CI, 5.9 to 11.3 months). Although rituximab re-treatment induced prolonged depletion of normal peripheral blood B cells in all patients, no significant decrease in serum immunoglobulin or complement level was observed. In conclusion, rituximab re-treatment was well tolerated, and it may produce a prolonged PFS in some patients with indolent B-cell NHL who showed initial response to rituximab.     

Rituximab in combination with CNOP chemotherapy in patients with previously untreated indolent non-Hodgkin's lymphoma

Rituximab, a chimeric monoclonal antibody, produces response rates of up to 73% in patients with previously untreated indolent non-Hodgkin's lymphoma (NHL), and has high activity when combined with chemotherapy. The purpose of this phase II study was to determine the efficacy and safety of rituximab plus cyclophosphamide, mitoxantrone, vincristine and prednisone (CNOP) chemotherapy in patients with indolent NHL. In all, 42 patients (median age 67 years) with previously untreated follicular, marginal zone or small lymphocytic/lymphoplasmacytic NHL received six infusions of rituximab (375 mg/m(2)) in combination with six cycles of CNOP. The overall response rate was 90% comprising 30 complete (71%) and eight partial (19%) responses. Although patients with marginal zone lymphoma or International Prognostic Index (IPI) score 3 had lower complete response rates, no significant difference in overall response rate was observed between the histological groups (P=0.24) or between patients stratified according to IPI score (P>0.05). Median overall survival, time-to-progression and response duration had not been reached after a median 19.5-month follow-up. In all, 31 patients (74%) are currently free from progression and 38 (90%) remain alive. Treatment was well tolerated. One patient (2%) experienced grade 3/4 infusion-related toxicity; 13 (31%) grade 3/4 leukopenia and 18 (43%) grade 3/4 neutropenia. Infection was observed in nine patients: eight (19%) grade 1/2 and one (2.4%) grade 3. This study demonstrates that combining rituximab with CNOP achieves high remission rates without significant additional toxicity in patients with previously untreated indolent NHL. Further follow-up will determine response duration and survival.     

Prognosis and outcome of non-Hodgkin lymphoma in primary Sjögren syndrome

Sj?gren syndrome (SS) has been associated with the development of non-Hodgkin lymphoma (NHL). From a cohort of 584 SS patients followed in our department from 1980 to 2010, we retrospectively analyzed 53 consecutive NHL cases. Considerations included histologic type, clinical manifestation and NHL staging, treatment, response rate and overall survival (OS), event-free survival (EFS), and standardized mortality ratio (SMR).Mucosa-associated lymphoid tissue (MALT) lymphomas constituted the majority (59%) of NHL subtypes, followed by nodal marginal zone lymphomas (NMZLs) (15%) and diffuse large B-cell lymphomas (DLBCLs) (15%). Six lymphoma patients died during the median follow-up of 40.8 months. The corresponding age/sex-adjusted SMR of SS with and without NHLs versus the general population was 3.25 (95% confidence interval [CI] 1.32-6.76) and 1.08 (95% CI, 0.79-1.45), respectively. A "watch and wait" policy was adopted for 9 patients with asymptomatic localized salivary MALT lymphomas. Eight patients with limited-stage MALT lymphomas and extraglandular manifestations were treated with rituximab. Ten MALT lymphoma patients with disseminated disease received chemotherapy with or without rituximab. The 3-year OS and EFS in patients with MALT lymphomas was 97% and 78%, respectively. Rituximab plus CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) was the chosen therapeutic intervention for patients with DLBCLs. A successful outcome was recorded for this group, with 100% OS and EFS at 3 years. Patients with NMZLs had a less favorable outcome, with a 3-year OS of 80% and EFS of 53%. Our results describe the course and prognosis of SS-associated NHL and highlight the need for a risk-stratified treatment approach.     

Bcl-2 clearance: optimising outcomes in follicular non-Hodgkin's lymphoma

The long median survival time of patients with follicular non-Hodgkin's lymphoma (NHL), means that the efficacy of new treatments are difficult to assess in the short term. Bcl-2 is an inhibitor of apoptosis and overexpression of the bcl-2 gene in the blood or bone marrow is a feature in up to 85% of patients with follicular NHL. Levels of bcl-2(+) cells in the peripheral blood or bone marrow therefore are a useful measure of disease status in such patients and can be detected by polymerase chain reaction (PCR). Complete bcl-2 clearance from the bone marrow (molecular remission) following autologous stem cell transplant (ASCT) for follicular NHL is considered to be an important prognostic factor for disease-free survival. Tumour cell contamination of the stem cell grafts used in ASCT is commonly associated with relapse. This can be addressed by purging the stem cell harvest prior to transplantation. Various methods of in vitro purging after stem cell collection have been shown to reduce the level of contamination but yield is invariably reduced and grafts remain bcl-2 positive. However, in vivo purging with rituximab during the process of collection has been used to obtain bcl-2-negative stem cell harvests without compromising the yield. Rituximab is a monoclonal antibody licensed for treatment of relapsed and refractory low-grade or follicular NHL. Rituximab targets the CD20 antigen, which is found on cells of the B cell lineage. When used for in vivo purging it depletes the peripheral blood of CD20-positive cells and prevents contamination by lymphoma cells. Molecular remission, as measured by bone-marrow bcl-2 clearance, has been achieved in 7/7 patients with follicular NHL at 1 year after treatment with ASCT using rituximab as an 'in vivopurse', followed by rituximab maintenance. Early clinical outcomes are also encouraging.     

Delayed redistribution of CD27, CD40 and CD80 positive B cells and the impaired in vitro immunoglobulin production in patients with non-Hodgkin lymphoma after rituximab treatment as an adjuvant to autologous stem cell transplantation

Recent studies have indicated that patients who received rituximab as an adjuvant to stem cell transplantation (SCT) demonstrated an increased risk of developing severe hypogammaglobulinaemia, which was found to be a result of delayed recovery of CD27 positive memory B cells and impaired isotype expression. It appears that rituximab influences both the quantity and quality of B-cell redistribution. Precisely how the B-cell repertoire regenerates after anti-CD20-mediated transient B-cell depletion in patients with non-Hodgkin lymphoma (NHL) remains to be elucidated. This study performed a phenotypical analysis of B cells in 17 NHL patients who received rituximab as an adjuvant to autologous SCT. The median period after final administration of rituximab was 36 months (range, 12-43 months). Surface antigen expression of CD27, CD40 and CD80 in NHL patients was statistically significantly different from healthy controls (n = 14). Moreover, B cells from NHL patients showed significantly impaired IgG and IgA production upon engagement of surface immunoglobulin receptors in the presence of interleukin (IL)-2, IL-10 and CD40 ligand in comparison with samples from healthy controls. The delayed recovery of memory B cells with an abnormal cell marker expression and function demonstrates that naive B cells may fail to differentiate into plasma cells, resulting in hypogammaglobulinaemia after autologous SCT and rituximab therapy.     

Incidence and nature of CD20-negative relapses following rituximab therapy in aggressive B-cell non-Hodgkin's lymphoma: a retrospective review

Re-treatment with rituximab for B-cell non-Hodgkin's lymphoma (NHL) relapsing after previous rituximab therapy has recently been shown to be clinically efficacious. Although the mechanism of resistance to rituximab re-treatment in non-responding patients is unknown, it is possible that loss of CD20 expression in the relapsed NHL could be important in some patients. We examined the incidence and nature of CD20 negative relapses following rituximab therapy in aggressive B-cell NHL treated at our institution. Of a total of 18 patients who received rituximab, 13 have relapsed, with 10 patients subsequently undergoing repeat tissue biopsy. Six of these 10 patients (60%) were shown to have lost CD20 expression by either immunohistochemistry and/or flow cytometry. Furthermore, three of the six patients who relapsed with CD20-negative NHL also suffered relapses at unusual anatomical sites. We conclude that loss of CD20 expression in aggressive B-cell NHL relapsing post-rituximab therapy is common. As such, repeat tissue biopsy should be undertaken to document CD20 expression by both flow cytometry and immunohistochemistry prior to considering repeated courses of rituximab in relapsed aggressive lymphomas.     

Effect of rituximab on the long-term outcome after high-dose therapy for relapsed B-cell non-Hodgkin’s lymphoma

To better define the role of rituximab in salvage and high-dose therapy (HDT) for relapsed or refractory non-Hodgkin’s lymphoma (NHL), patients treated before the implementation of rituximab in salvage and HDT (n=57, control group) were compared with patients with rituximab included in this procedure (n=36, study group). All patients had been antibody-naive at this point, and analyses were performed separately for 22 and 31 patients with aggressive, and 14 and 26 patients with indolent NHL, respectively. All patients received two courses of salvage therapy, predominantly dexamethasone, BCNU, etoposide, cytosine arabinoside, melphalan. Conditioning regimens included BCNU, etoposide, cytosine arabinoside, melphalan; BCNU, etoposide, cytosine arabinoside, cyclophosphamide or total body irradiation and cyclophosphamide, with rituximab added for patients in the study group. Despite the absence of differences in stem cell collection, haematopoietic recovery was delayed in patients with aggressive NHL treated in the study group: median days to absolute neutrophil count more than 0.5×10⁹/l, 11 vs 10 (p=0.01), and platelets more than 20×10⁹/l, 14 vs 11 (p=0.0005), with an increased requirement for platelet transfusions. No similar observations were made in indolent lymphoma patients. Remission rates were superior for patients with aggressive NHL in the study group. With a median follow-up of 7.25 and 4.5 years, this resulted in an improvement in OS at 4.5 years: 67 vs 45% (95% confidence interval, 47–87% vs 28–64%; p=0.0468). For patients with indolent lymphoma, no comparable benefit was detectable. Our data support the use of rituximab in HDT for patients with aggressive NHL. For patients with indolent NHL, only longer follow-up and/or randomized trials may help to fully determine the impact of rituximab on the outcome after HDT.     

Decreasing rates of Kaposi's sarcoma and non-Hodgkin's lymphoma in the era of potent combination anti-retroviral therapy

OBJECTIVE: To describe the changing incidence of Kaposi's sarcoma (KS) and non-Hodgkin's lymphoma (NHL) in people with HIV in Australia during the time period of introduction of potent combination anti-retroviral therapy. DESIGN: A national, population-based linkage study of cancer and HIV registration data. METHODS: We calculated person-year rates of KS and NHL in people after reporting of HIV diagnosis. Trends in cancer incidence rates were examined, based on four time periods defined by the availability of specific anti-retroviral therapies. RESULTS: Linkage identified 206 cases of KS and 235 cases of NHL in 8108 people reported with HIV infection. There was an increasing trend in NHL incidence rates over the four time periods (P for trend, 0.012), but incidence for the period since the availability of the new therapies was significantly lower than that for the period immediately prior (incidence rate ratio 0.58; 95% confidence interval, 0.36-0.92). Incidence of KS had been decreasing prior to the new therapies and declined further since their widespread use (P for trend, 0.045). CONCLUSIONS: Population-based incidence rates of AIDS related KS and NHL have decreased since the widespread use of potent anti-retroviral therapies in Australia. NHL incidence decreased less than KS, and NHL is now the most common AIDS-associated cancer in Australia.     

Rituximab monoclonal antibody as initial systemic therapy for patients with low-grade non-Hodgkin lymphoma

Rituximab, a chimeric antibody that targets CD20(+) B cells, produces a 48% response rate in patients with refractory low-grade non-Hodgkin lymphoma. In this phase II trial, patients with low-grade non-Hodgkin lymphoma who had previously received no systemic therapy were treated with rituximab, 375 mg/m(2), administered by IV infusion for 4 consecutive weeks. Patients with objective response or stable disease received repeat 4-week courses of rituximab at 6-month intervals. At the time of initial reevaluation at 6 weeks, 21 of 39 patients (54%) had objective response to treatment, and an additional 14 patients (36%) had stable disease or minor response. Response rates were similar in patients with follicular and small lymphocytic (CLL-type) lymphoma (52% versus 57%, respectively). At present, follow-up is short and only 13 patients have undergone a second course of rituximab treatment. However, 4 additional responses were documented either prior to the second course of rituximab (2 patients) or following the second course (2 patients) and 4 patients improved from partial to complete response. The current response rate is 64%, with 6 complete responses (15%). Treatment with rituximab was well tolerated, with only 1 patient experiencing grade 3/4 infusion-related toxicity. Rituximab is well tolerated and highly active in patients with low-grade non-Hodgkin lymphoma previously untreated with systemic therapy. Although further follow-up is required, the demonstration of minimal toxicity and considerable activity of this new biologic agent represents an important beginning of more specific, less toxic treatment for this important group of cancer patients.     

Combination immunotherapy with rituximab and interleukin 2 in patients with relapsed or refractory follicular non-Hodgkin's lymphoma

Rituximab has significant activity as a single agent in the treatment of follicular non-Hodgkin's lymphoma (NHL). Interleukin 2 (IL-2) is a lymphokine that increases effector cell number. In an effort to augment antibody-dependent cell-mediated cytotoxicity (ADCC) associated with rituximab therapy, low-dose IL-2 was added to a standard rituximab regimen and patients were evaluated for safety and efficacy. Twenty patients with relapsed or refractory follicular NHL were treated with IL-2 (1.2 MIU/m(2)/d for 56 d subcutaneously) as outpatients. Rituximab (375 mg/m(2)) was given on d 15, 22, 29 and 36. The regimen was well tolerated and only three patients required dose adjustments in IL-2. Infusional toxicity associated with rituximab was not exacerbated by IL-2. Peripheral blood immunophenotyping demonstrated significant increases in circulating CD8+ and CD56+ lymphocytes in all evaluable patients (P = 0.0002). Increases in total eosinophil number were observed in all patients. Eleven patients responded to therapy, for an overall response rate of 55%. Four additional patients had stable disease. For these 15 patients, the median time to progression exceeded 13 months. We conclude concomitant cytokine therapy to enhance ADCC with monoclonal antibody therapy was well tolerated and did not exacerbate antibody-related infusional toxicity. Further studies of this rational combination are warranted and ongoing.     

Rituximab combined with DexaBEAM followed by high dose therapy as salvage therapy in patients with relapsed or refractory B‐cell lymphoma: mature results of a phase II multicentre study

Salvage therapy followed by high‐dose therapy (HDT) remains a mainstay for patients with relapsed lymphoma, however no optimal regimen has been defined. Here we report on the results of R‐DexaBEAM (rituximab, dexamethasone, carmustine, etoposide, cytarabine, melphalan) followed by HDT. Patients aged 18–65 years, Eastern Cooperative Oncology Group performance score 0–2, with relapsed/refractory B‐cell non‐Hodgkin lymphoma (NHL) were eligible. R‐Dexa‐BEAM was given for two cycles followed by stem cell mobilization and HDT. Primary endpoint of the trial was progression‐free‐survival (PFS). One hundred and three patients were included: aggressive NHL (aNHL): diffuse large B‐cell lymphoma 55, mantle cell lymphoma 7, follicular lymphoma (FL) grade 3: 5, indolent Lymphoma (iNHL): FL grade 1–2: 29, marginal zone lymphoma 6, Immunocytoma 1. The overall response rate after salvage therapy was 62% for aNHL and 78% for iNHL patients. 66% of patients with aNHL and 86% with iNHL underwent HDT. Treatment‐related mortality for HDT was 1·3%. For aNHL patients, the median PFS was 0·83 years with 44% alive at the median follow‐up of 7·3 years. Corresponding figures for iNHL were: median PFS 3·7 years and 72% alive after 8 years. The combination of rituximab with DexaBEAM followed by HDT resulted in high response rates and sustained remissions in responders. R‐DexaBEAM followed by HDT can be considered a valid salvage option for NHL.     

Current treatment strategy of diffuse large B-cell lymphomas

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin’s lymphoma, accounting for approximately 25–30% of all new patients. Rituximab, a genetically engineered chimeric monoclonal antibody that specifically binds to CD20, is the first monoclonal antibody approved for the treatment of B-cell lymphoma. Rituximab significantly improves treatment outcome in DLBCL. A large-phase III study demonstrated improved overall survival (OS) in patients with DLBCL treated with R-CHOP therapy. The Groupe d’Etude des Lymphomes de l’Adulte (GELA), Eastern Cooperative Oncology Group (ECOG) and German High-Grade Non-Hodgkin Lymphoma Study Group (DSHNHL) studies designed for patients older than 60 years have clearly shown prolonged event-free survival (EFS) and OS among patients who received rituximab and chemotherapy. For patients under 60 years, the MabThera International Trial Group (MInT) study demonstrated improved EFS and OS after the addition of rituximab to CHOP therapy. However, the R-CHOP therapy does not provide a satisfactory treatment outcome in the high-risk group according to the international prognostic index. Therefore, R-CHOP therapy is the new standard therapy in elderly and young, low-risk DLBCL patients. For young, high-risk DLBCL patients, treatment that incorporates rituximab and hematopoietic stem cell transplantation has been administered in clinical studies.