The role of radiotherapy for patients over age 60 with diffuse large B-cell lymphoma in the rituximab era

Association of overall survival benefit of radiotherapy with progression-free survival after chemotherapy for diffuse large B-cell lymphoma: A systematic review and meta-analysis

Objective

To evaluate whether improved progression-free survival (PFS) from radiotherapy (RT) translates into an overall survival (OS) benefit for diffuse large B-cell lymphoma (DLBCL).

Methods

A systematic literature search identified randomized controlled trials (RCTs) and retrospective studies that compared combined-modality therapy (CMT) with chemotherapy (CT) alone. Weighted regression analyses were used to estimate the correlation between OS and PFS benefits. Cohen's kappa statistic assessed the consistency between DLBCL risk-models and PFS patterns. Furthermore, the benefit trend of RT was analyzed by fitting a linear regression model to the pooled hazard ratio (HR) according to the PFS patterns.

Results

For both 7 RCTs and 52 retrospective studies, correlations were found between PFS HR (HRPFS) and OS HR (HROS) at trial level (r = 0.639-0.876), and between PFS and OS rates at treatment-arm level, regardless of CT regimens (r = 0.882-0.964). Incorporating RT into CT increased about 18% of PFS, and revealed a different OS benefit profile. Patients were stratified into four CT-generated PFS patterns (>80%, >60-80%, >40-60%, and ≤40%), which was consistent with risk-stratified subgroups (kappa > 0.6). Absolute gain in OS from RT ranged from ≤5% at PFS >80% to about 21% at PFS ≤40%, with pooled HROS from 0.70 (95% CI, 0.51-0.97) to 0.48 (95% CI, 0.36-0.63) after rituximab-based CT. The OS benefit of RT was predominant in intermediate- and high-risk patients with PFS ≤ 80%.

Conclusion

We demonstrated a varied OS benefit profile of RT to inform treatment decisions and clinical trial design.

Diffuse Large B-Cell Lymphoma Treated With R-CHOP in a Resource-Limited Setting in South Africa: A Real-World Study

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma worldwide and particularly in Africa, where the incidence of HIV is the highest in the world. R-CHOP is the standard of care regimen for DLBCL, but access to rituximab is limited in developing countries.

METHODS

This is a retrospective cohort study that included all HIV-negative patients with DLBCL who received R-CHOP at a single institution from January 2012 to December 2017. Clinical and demographic data were collected to assess factors that influenced survival.

RESULTS

Seventy-three patients were included. Median age was 55 (17-76), 67.1% of patients were younger than 60 years, and 60.3% were female. Most presented with stages III/IV disease (53.5%) but with good performance status (56.% PS 0 and 1). Progression-free survival at 3 and 5 years was 75% and 69%, and overall survival at 3 and 5 years was 77% and 74%, respectively. Median survival had not been reached with a median follow-up of 3.5 years(0.13-7.9). Overall survival was significantly affected by performance status (P = .04), but not by IPI or age. Survival was significantly associated with response to chemotherapy after 4-5 cycles of R-CHOP (P = 0.005).

CONCLUSIONS

Treatment of DLBCL with R-CHOP is feasible and can achieve good outcomes in resource-limited settings with rituximab-based chemotherapy. Poor performance status was the most important adverse prognostic factor in this cohort of HIV-negative patients.

Consolidative Radiotherapy after Complete Remission following R-CHOP Immunochemotherapy in Stage III-IV Diffuse Large B-Cell Lymphoma Patients: A Systematic Review and Meta-Analysis

Patients with diffuse large B-cell lymphoma (DLBCL) are treated with rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). The role of consolidative radiation therapy (RT) remains unclear among patients with advanced DLBCL who achieved complete remission (CR) after R-CHOP immunochemotherapy. The current systematic review and meta-analysis aimed to clarify the role of consolidative RT among these patients. The MEDLINE, Embase, and Cochrane Library databases were searched for studies comparing RT to no RT following CR after R-CHOP immunochemotherapy in Ann Arbor stage III-IV DLBCL patients. Overall survival (OS) was the primary endpoint, and disease-free survival (DFS) was the secondary endpoint. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to assess the primary and secondary outcomes. Review Manager (version 5.4) was used to analyze the data. Six retrospective studies involving 813 patients who received R-CHOP ± consolidative RT were identified. OS was higher in the consolidative RT group, with an HR of 2.01 and a 95% CI of 1.30 to 3.12 (p = 0.002). DFS was also higher in the RT group, with an HR of 2.18 and a 95% CI of 1.47 to 3.24 (p < 0.0001). The results suggested that consolidative RT improved OS and DFS compared to no RT among advanced-stage DLBCL patients. Further research is needed to determine the optimal radiation fields and the appropriate indications for consolidative RT for advanced-stage DLBCL patients in the rituximab era.

Radiotherapy for Non-Hodgkin Lymphomas

Radiotherapy (RT) plays a diverse and essential role in the contemporary management of non-Hodgkin lymphoma (NHL) and remains the single most powerful monotherapeutic intervention for both aggressive and indolent subtypes. Over the past decade, there have been significant advancements in radiation oncology practice, which have made modern treatments safer and more conformal. Despite this sophistication and evidence supporting a continued role for RT, numerous data suggest that utilization is on the decline. In this review, we discuss the rationale for RT in 4 commonly encountered scenarios: combined modality therapy for limited-stage aggressive NHL, consolidation therapy for advanced-stage aggressive NHL, and the changing roles of salvage RT for relapsed/refractory NHL in an era of new frontiers such as cellular therapies. We also evaluate current strategies to treat indolent histologies. We conclude with perspectives on how RT for the hematological malignancies may continue to evolve.

Retracted article: Adjuvant radiotherapy in patients with diffuse large B-cell lymphoma in advanced stage (III/IV) improves the outcome in the rituximab era

Statement of Retraction: Adjuvant radiotherapy in patients with diffuse large B-cell lymphoma in advanced stage (III/IV) improves the outcome in the rituximab era We, the Editor[s] and Publisher of Hematology, have retracted the following article: Avilès, A, Nambo, M-J, Calva, A, et al. Adjuvant radiotherapy in patients with diffuse large B-cell lymphoma in advanced stage (III/IV) improves the outcome in the rituximab era. Hematology. 2019;24:507-511; DOI: 10.1080/10245332.2018.1423880 The above article has been retracted as a result of concerns regarding the data upon which the presented research has been based. After re-examination and several independent expert reviews the consensus is that the data and results are not reliable and therefore the article must be retracted. The authors have agreed with this decision. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as "Retracted".

Venetoclax Synergizes with Radiotherapy for Treatment of B-cell Lymphomas

Constitutive B-cell receptor signaling leads to overexpression of the antiapoptotic BCL-2 protein and is implicated in the pathogenesis of many types of B-cell non-Hodgkin lymphoma (B-NHL). The BCL-2 small-molecule inhibitor venetoclax shows promising clinical response rates in several lymphomas, but is not curative as monotherapy. Radiotherapy is a rational candidate for combining with BCL-2 inhibition, as DNA damage caused by radiotherapy increases the activity of pro-apoptotic BCL-2 pathway proteins, and lymphomas are exquisitely sensitive to radiation. We tested B-NHL responses to venetoclax combined with either external beam radiotherapy or radioimmunotherapy (RIT), which joins the selectivity of antibody targeting with the effectiveness of irradiation. We first tested cytotoxicity of cesium-137 irradiation plus venetoclax in 14 B-NHL cell lines representing five lymphoma subtypes. Combination treatment synergistically increased cell death in 10 of 14 lines. Lack of synergy was predicted by resistance to single-agent venetoclax and high BCL-XL expression. We then assessed the efficacy of external beam radiotherapy plus venetoclax in murine xenograft models of mantle cell (MCL), germinal-center diffuse large B-cell (GCB-DLBCL), and activated B-cell (ABC-DLBCL) lymphomas. In each model, external beam radiotherapy plus venetoclax synergistically increased mouse survival time, curing up to 10%. We finally combined venetoclax treatment of MCL and ABC-DLBCL xenografts with a pretargeted RIT (PRIT) system directed against the CD20 antigen. Optimal dosing of PRIT plus venetoclax cured 100% of mice with no detectable toxicity. Venetoclax combined with radiotherapy may be a promising treatment for a wide range of lymphomas Cancer Res; 77(14); 3885-93. ©2017 AACR.

Diffuse large B-cell lymphoma in very elderly patients over 80 years old: Incorporating consolidative radiation therapy into management decisions

Purpose

The population of patients aged 80 years or older who are diagnosed with diffuse large B-cell lymphoma (DLBCL) continues to increase, but an optimal treatment strategy has not been established. We sought to examine the influence of consolidative radiation therapy (RT) on outcome and toxicity among the very elderly diagnosed with stage I-IV DLBCL.

Methods and materials

We evaluated 131 patients treated at a single institution between 2002 and 2014 who were eligible for RT after successful treatment with chemotherapy.

Results

The median age was 83 years (range, 80-96). Advanced-stage disease was present in 61.8% of patients. Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone was administered to 80% of patients (n = 108), and 23.7% of patients received consolidative RT. Among early-stage (ES) patients treated with 3 to 4 cycles of chemotherapy and RT (n = 12) versus 6 to 8 cycles of chemotherapy alone (n = 17), there were no statistically significant differences in 3-year disease-free, progression-free, or overall survival rates. The 3 year disease-free survival was 91.7% versus 88.2% among patients treated with combined modality therapy versus chemotherapy alone (P = .78). The 3-year overall survival was 82.5% versus 87.5% among patients treated with combined modality therapy compared with chemotherapy alone (P = .852). Anemia and neuropathy occurred more frequently among ES patients who received 6 to 8 cycles of chemotherapy alone. Among advanced-stage patients with bulky disease (n = 35), consolidative RT to sites of bulky disease may have improved local control (3-year local control, 100% vs 60.3%, P = .160).

Conclusions

Among patients aged 80 years or older who have with ES DLBCL, 3 to 4 cycles of chemotherapy followed by RT is at least equivalent in efficacy to chemotherapy alone and is associated with lower levels of toxicity, which suggests that it may be a better choice for therapy when trying to balance treatment efficacy and tolerability.

[Radiotherapy in localized stages of follicular and diffuse non-Hodgkin's lymphomas]

Treatment with monoclonal antibodies, especially rituximab, is more and more frequent and questions the interest of radiotherapy in limited stages of diffuse B-cell large cell and follicular non-Hodgkin's lymphomas. From a review of literature, it appears that radiotherapy is of interest in bulky disease, patients with incomplete metabolic response, elderly patients receiving short chemotherapy and those with recurrence after exclusive chemotherapy. Finally, this article gives recommendations on available techniques of radiotherapy and doses to be delivered.