Impact of Consolidation Radiation Therapy in Stage III-IV Diffuse Large B-cell Lymphoma With Negative Post-Chemotherapy Radiologic Imaging

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.

Efficacy and toxicity of infradiaphragmal radiotherapy fields in lymphoma patients: a single-centre experience

PURPOSE

Data on efficacy and toxicity of infradiaphragmal radiotherapy fields in lymphoma patients are scarce. We therefore performed this retrospective study to analyse our experience with radiotherapy exclusively to infradiaphragmal fields.

MATERIALS AND METHODS

we retrospectively evaluated 101 patients treated between 2003 and 2014. Median dose was 36 Gy, range 4 to 54 Gy. Medium dose per fraction was 2 Gy, range 1.5 to 7 Gy.

RESULTS

After a median follow-up of 66 months (range 1-211 months), we observed lymphoma recurrence in 38 patients (38%), five in the RT field and 33 out-of-field. Recurrences were significantly more frequent in the salvage group (17 out-of-field and 4 in-field in 31 patients) than in adjuvant group (16 out-of-field and 1 in-field in 70 patients; p < 0.001). The 2-, 5- and 10-year event-free survival (EFS) rates were 62%, 56% and 54%. The 2-, 5- and 10-year overall survival (OS) rates for the entire group of patients are 73%, 60% and 54%, respectively. Acute side effects occurred in 43 (43%) patients, most frequent gastrointestinal in 26 (26%) patients. Late side effects occurred in 12 (12%) of all patients, 6 of 23 (26%) followed up for more than 10 years. Six patients developed secondary cancers, four gastrointestinal disturbances, two diabetes mellitus and three renal failure.

CONCLUSION

Radiotherapy is an effective and safe treatment option for patients with infradiaphragmatic lymphoma providing excellent local disease control with minimal late toxicity. Infradiaphragmatic lymphoma localization should not be regarded as a contraindication for use of radiotherapy. However, patients should be monitored for a secondary malignancy.

Clinical characteristics and treatment outcomes of Chinese diffuse large B-cell lymphoma patients in the era of rituximab (2005-2018)

Background

Rituximab combined with cyclophosphamide, doxorubicin hydrochloride, vincristine, and prednisone (R-CHOP) regimen has improved the survival of diffuse large B-cell lymphoma (DLBCL) patients worldwide, compared with CHOP alone. Several limitations were seen in previous studies of Chinese DLBCL patients treated with R-CHOP or R-CHOP-like regimens. This study aimed to investigate the clinical characteristics and treatment outcomes of Chinese DLBCL patients treated with the standard first-line treatment.

Methods

Clinical data were collected from DLBCL patients who received frontline R-CHOP or R-CHOP-like regimens at the Cancer Hospital Chinese Academy of Medical Sciences & Peking Union Medical College (CHCAMS) between January 1, 2005, and December 31, 2018. The treatment outcomes were compared with those of patients diagnosed with DLBCL between 2004 and 2017 and who received immunochemotherapy from the United States Surveillance, Epidemiology, and End Results (SEER) database. Survival rates were estimated using the Kaplan-Meier method and compared using the log-rank test. Multivariate analysis of progression-free survival (PFS) and overall survival (OS) was performed using Cox proportional hazard regression.

Results

Overall, 1084 patients from the CHCAMS and 4013 patients from the SEER database were included in the study. As of April 30, 2022, the median follow-up period for the CHCAMS group was 87.3 (range: 0.5-195.4) months. For the CHCAMS group, the 5-year PFS and OS rates were 61.7% (95% confidence interval [CI]: 58.8-64.7%) and 70.6% (95% CI: 67.8-73.4%), respectively. For the SEER group, the 5-year OS rate was 66.5% (95% CI: 65.0-68.0%), which was inferior to that of the CHCAMS group (P ​< ​0.001). After adjusting for clinical factors and treatment, no significant difference was observed in the OS between the CHCAMS and SEER groups (P ​= ​0.867). In the CHCAMS group, multivariate analysis showed that an Eastern Cooperative Oncology Group performance status score ≥2, presence of B symptoms, Ann Arbor stage III-IV, elevated serum β2-microglobulin levels, and bulky mass were independent adverse prognostic factors affecting PFS and OS (P ​< ​0.05). Additionally, patients aged over 60 years, elevated lactate dehydrogenase levels, and more than two extranodal sites were independent adverse prognostic factors for OS (P ​< ​0.05). Local radiotherapy was significantly associated with better PFS (P ​< ​0.001) and OS (P ​= ​0.001).

Conclusion

After adjusting for clinical and treatment-related factors, no significant difference was observed in the 5-year OS rate between Chinese DLBCL patients treated with standard first-line treatment and those from the SEER database.

Positron Emission Tomography Molecular Imaging for Phenotyping and Management of Lymphoma

Positron emission tomography (PET) represents molecular imaging for non-invasive phenotyping of physiological and biochemical processes in various oncological diseases. PET imaging with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) for glucose metabolism evaluation is the standard imaging modality for the clinical management of lymphoma. One of the ¹⁸F-FDG PET applications is the detection and pre-treatment staging of lymphoma, which is highly sensitive. ¹⁸F-FDG PET is also applied during treatment to evaluate the individual chemo-sensitivity and accordingly guide the response-adapted therapy. At the end of the therapy regiment, a negative PET scan is indicative of a good prognosis in patients with advanced Hodgkin's lymphoma and diffuse large B-cell lymphoma. Thus, adjuvant radiotherapy may be alleviated. Future PET studies using non-¹⁸F-FDG radiotracers, such as ⁶⁸Ga-labeled pentixafor (a cyclic pentapeptide that enables sensitive and high-contrast imaging of C-X-C motif chemokine receptor 4), ⁶⁸Ga-labeled fibroblast activation protein inhibitor (FAPI) that reflects the tumor microenvironment, and ⁸⁹Zr-labeled atezolizumab that targets the programmed cell death-ligand 1 (PD-L1), may complement ¹⁸F-FDG and offer essential tools to decode lymphoma phenotypes further and identify the mechanisms of lymphoma therapy.

PET-guided treatment for personalised therapy of Hodgkin lymphoma and aggressive non-Hodgkin lymphoma

FDG-PET scanning has a central role in lymphoma staging and response assessment. There is a growing body of evidence that PET response assessment during and after initial systemic therapy can provide useful prognostic information, and PET response has an evolving role in guiding patient care. This review provides a perspective on the role of PET response assessment for individualised management of patients with the most common aggressive lymphomas, Hodgkin lymphoma and diffuse large B-cell lymphoma.

Improved Progression-Free Survival for Bulky and Non-Bulky Advanced Stage Diffuse Large B-Cell Lymphoma With Consolidative Radiation Therapy: A Bi-Institutional Analysis

Background The role of consolidative radiation therapy (RT) for advanced-stage diffuse large B-cell lymphoma (DLBCL) is not fully established. A growing body of data suggests a role for consolidative RT in select stage III-IV DLBCL patients and emerging data from randomized studies further address the role of RT in advanced-stage patients initially presenting with bulky disease. Methods Patients with treatment-naive stage III-IV DLBCL treated at two institutions who achieved a clinically complete response to systemic therapy were included. Patients with either bulky or non-bulky disease were included, but those with the relapsed or refractory disease were excluded. Kaplan-Meier analysis was performed to determine the impact of consolidative RT. Univariate and multivariable analyses were performed using a Cox proportional hazards model. Results One hundred eighty-eight patients received systemic therapy consisting of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; 79%), another rituximab-based regimen (9%), or chemotherapy alone (12%). Clinical response was assessed using conventional CT or PET-CT. Sixty-eight patients (36%) received consolidative RT (median dose 30 Gy). Consolidative RT conferred a 36.7% absolute benefit in five-year progression-free survival (PFS; 85.9% vs. 49.2%, log rank p < 0.0001), a 14.5% absolute benefit in five-year overall survival (OS; 87.4% vs. 72.9%, log rank p = 0.0134), and a 37.0% absolute benefit in five-year LC (91.9% vs. 54.9%, log rank p < 0.0001). On multivariable analysis, consolidative RT was associated with improved PFS (HR 0.23, 95% CI 0.10-0.52, p < 0.001) and LC (HR 0.20, 95% CI 0.07-0.59, p = 0.003). Patients receiving consolidative RT demonstrated significantly improved PFS for tumors measuring both <5 cm (log rank p = 0.0454) and ≥5 cm (log rank p = 0.0003). Conclusions For patients with stage III-IV DLBCL who achieve clinical complete response after systemic therapy, consolidative RT improves PFS for all patients, including those with the non-bulky disease. This benefit persists in the setting of rituximab-based systemic therapy.

Long-term results of PET-guided radiation in patients with advanced-stage diffuse large B-cell lymphoma treated with R-CHOP

Consolidative radiation therapy (RT) for advanced-stage diffuse large B-cell lymphoma (DLBCL) remains controversial, with routine practice continuing to include RT in patients with initial bulky disease or residual masses. Positron emission tomography (PET)-computed tomography is a sensitive modality for detecting the presence of residual disease at the end of treatment (EOT). A PET-guided approach to selectively administering RT has been the policy in British Columbia since 2005. Patients with advanced-stage DLBCL diagnosed from 1 January 2005 to 1 March 2017 and treated with at least 6 cycles of R-CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone plus rituximab), who underwent EOT PET, were included in this analysis. Those with complete metabolic response (PET-negative [PET-NEG]) were observed; those with PET-positive (PET-POS) scans were offered consolidative RT, when feasible. Of the patient records reviewed, 723 were identified, with median follow-up of 4.3 years: 517 (72%) were PET-NEG; 206 (28%) were PET-POS. Time to progression (TTP) and overall survival (OS) at 3 years were 83% vs 56% and 87% vs 64%, in patients with PET-NEG and PET-POS scans, respectively. PET-POS patients with nonprogressing disease treated with consolidative RT (109 and 206; 53%) had outcomes approaching those of PET-NEG patients, with 3-year estimates of 76% and 80% for TTP and OS. PET-NEG patients who had bulky disease (≥10 cm) at diagnosis had outcomes indistinguishable from those without bulk, despite the omission of RT. These data suggest that patients with advanced-stage DLBCL who are PET-NEG at EOT and receive no RT have excellent outcomes. 18F-fluorodeoxyglucose-PET can reliably guide selective administration of consolidative RT, even in patients with initially bulky disease.

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.

Emerging Role of Consolidative Radiotherapy After Complete Remission Following R-CHOP Immunochemotherapy in Stage III-IV Diffuse Large B-Cell Lymphoma: A Single Institutional and Case-Matched Control Study

Purpose

The role of consolidative radiotherapy (RT) after complete-remission (CR) following rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in advanced-stage diffuse large B-cell lymphoma (DLBCL) remains unclear. We retrospectively analyzed the survival outcomes and patterns of failure with our institutional experience.

Material and Methods

Between 2009 and 2018, 206 patients with stage III-IV DLBCL achieved CR after receiving R-CHOP. Propensity-score matching was used to analyze the role of consolidative RT. The consolidative RT group (n = 34) and the R-CHOP alone group (n = 68) were matched at a 1:2 ratio. After propensity-score matching, 102 patients were analyzed.

Results

With a median follow-up of 39.7 months, 26 patients (25.5%) showed local recurrence. Only one patient failed at the previous RT field. RT was delivered to bulky sites, head and neck lesions, testes, and bone with median dose of 30.6 Gy. The most common site of failure was head and neck lesions followed by bulky sites. The 5-year overall survival (OS), progression-free survival (PFS), and isolated-local recurrence free survival (LRFS) were 73.5, 64.0, and 79.9%. In univariate and multivariate analysis, bone marrow involvement and consolidative RT were associated with isolated LRFS (p = 0.006 and 0.032) significantly.

Conclusion

Consolidative RT improved isolated local control. Based on the pattern of failure, we carefully suggest to radiate on initially involved bulky sites or head and neck lesions. Further studies need to be done to find out the optimal radiation dose and selection of RT site.

Biomarkers and novel therapeutic approaches for diffuse large B-cell lymphoma in the era of precision medicine

Despite the great efforts for better treatment options for diffuse large B-cell lymphoma (DLBCL) (most common form of non-Hodgkin lymphoma, NHL) to treat and prevent relapse, it continues to be a challenge. Here, we present an overview of DLBCL and address the diagnostic assays and molecular techniques used in its diagnosis, role of biomarkers in detection, treatment of early and advanced stage DLBCL, and novel drug regimens. We discuss the significant biomarkers that have emerged as essential tools for stratifying patients according to risk factors and for providing insights into the use of more targeted and individualized therapeutics. We discuss techniques such as gene expression studies, including next-generation sequencing, which have enabled a more understanding of the complex pathogenesis of DLBCL and have helped determine molecular targets for novel therapeutic agents. We examine current treatment approaches, outline the findings of completed clinical trials, and provide updates for ongoing clinical trials. We highlight clinical trials relevant to the significant fraction of DLBCL patients who present with complex cases marked by high relapse rates. Supported by an increased understanding of targetable pathways in DLBCL, clinical trials involving specialized combination therapies are bringing us within reach the promise of an effective cure to DLBCL using precision medicine. Optimization of therapy remains a crucial objective, with the end goal being a balance between high survival rates through targeted and personalized treatment while reducing adverse effects in DLBCL patients of all subsets.

Role of Radiation Therapy Differs Between Stages in Primary Bone Large B-Cell Lymphoma in Rituximab Era: A Population-Based Analysis

Background: Primary bone B-cell lymphoma (PB-DLBCL) is a rare entity for which existing data is limited. Whether radiotherapy (RT) should be omitted in the modern treatment of PB-DLBCL is still under debate. We used the SEER database to compare the outcomes among adult patients treated with and without RT in rituximab era. Methods: We included adult patients with PB-DLBCL diagnosed from 2002 to 2016 from SEER 18. The effect of RT on overall survival (OS) using univariate (UVA) and multivariate (MVA) Cox proportional regression and propensity score matching (PSM) was assessed for the entire cohort and subgroups by stages. We calculated the standardized incidence ratio to estimate the short- and long-term risk for second primary malignancies (SPM) from 2002 to 2016 in SEER 18 and 1983-2016 in SEER 9. Results: A total of 1,320 patients were identified, including 856 with early-stage (ES) and 464 with advanced-stage (AS). A decreasing trend was observed in the ES cohort after 2002, while the rate of RT utilization remained stable in the AS cohort over the past three decades. Most patients in ES (63.9%) underwent RT, whereas only 42.2% of AS patients received it. RT significantly improved survival both in UVA and MVA (P < 0.001, P = 0.010, respectively). PSM analysis further validated the survival advantage of RT (P = 0.018). Moreover, a novel web-based prediction model was established to individualize the potential benefit from RT. In subgroup analyses, OS was improved with RT in those who had ES disease (p < 0.001) but not in those who had AS disease (P = 0.776). With short-term follow up in SEER 18, none of the subgroups showed a significantly elevated risk of developing SPMs. However, RT significantly elevated the late toxicities of second malignancies in ES patients diagnosed at the age of 18-39 or those with appendicular sites of bone involvement. Conclusion: This population-based analysis is the largest PB-DLBCL dataset to date and demonstrates a significant survival benefit associated with RT in early stages rather than advanced stages. In the absence of randomized controlled trials, RT should be considered in ES disease with cautions of second cancers in specific subsets of patients.

Are Higher Doses of Consolidation Radiation Therapy Necessary in Diffuse Large B-cell Lymphoma Involving Osseous Sites?

Purpose

This study aimed to evaluate whether higher doses of consolidation radiation therapy (RT), which have been traditionally recommended for osseous sites in diffuse large B-cell lymphoma (DLBCL), are still necessary.

Methods and materials

Patients with DLBCL with osseous involvement treated with first-line chemotherapy followed by consolidation RT between 1995 and 2016 were reviewed. The primary endpoint was 5-year freedom from local recurrence, estimated using the Kaplan-Meier method. Outcomes based on the RT dose received were also assessed.

Results

A total of 51 patients were identified. The most common chemotherapy regimens were rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (80%) and cyclophosphamide, doxorubicin, vincristine, and prednisone (12%) with a median of 6 cycles (range, 3-8 cycles). After chemotherapy, 82% of patients achieved a complete response (CR), and 18% achieved a partial response (PR). All patients in PR were deemed appropriate for consolidation RT. The median dose was 29 Gy (24 Gy for CR; 36 Gy for PR). After a median follow-up of 86 months, 8 patients relapsed, with 2 relapses in the RT field after consolidation RT of 30 and 39.6 Gy, respectively. Overall, the 5-year freedom from local recurrence was 96% (95% confidence interval [CI], 91%-100%), disease-free survival was 76% (95% CI, 65%-89%), and overall survival was 86% (95% CI, 76%-96%). No dose-response relationship was observed.

Conclusions

In patients with DLBCL with osseous involvement who achieved a CR after first-line chemotherapy, 20 to 30 Gy of consolidation RT led to high rates of local control. Higher doses should be reserved for patients in PR.

FDG-PET/CT in the management of lymphomas: current status and future directions

FDG-PET/CT is the current state-of-the-art imaging in lymphoma and plays a central role in treatment decisions. At diagnosis, accurate staging is crucial for appropriate therapy selection: FDG-PET/CT can identify areas of lymphoma missed by CT alone and avoid under-treatment of patients with advanced disease stage who would have been misclassified as having limited stage disease by CT. Particularly in Hodgkin lymphoma, positive interim FDG-PET/CT scans are adversely prognostic for clinical outcomes and can inform PET-adapted treatment strategies, but such data are less consistent in diffuse large B-cell lymphoma. The use of quantitative FDG-PET/CT metrics using metabolic tumour volume, possibly in combination with other biomarkers, may better define prognostic subgroups and thus facilitate better treatment selection. After chemotherapy, FDG-PET/CT response is predictive of outcome and may identify a subgroup who benefit from consolidative radiotherapy. Novel therapies, in particular immunotherapies, exhibit different response patterns than conventional chemotherapy, which has led to modified response criteria that take into account the risk of transient pseudo-progression. In relapsed lymphoma, FDG-PET/CT after second-line therapy and prior to high-dose therapy is also strongly associated with outcome and may be used to guide intensity of salvage therapy in relapsed Hodgkin lymphoma. Currently, FDG-PET/CT has no role in the routine follow-up after complete metabolic response to therapy, but it remains a powerful tool for excluding relapse if patients develop clinical features suggestive of disease relapse. In conclusion, FDG-PET/CT plays major roles in the various phases of management of lymphoma and constitutes a step towards the pursuit of personalized treatment.

INFRADIAPHRAGMAL RADIOTHERAPY IN PATIENTS WITH LYMPHOMA: VOLUME DEFINITION AND SIDE EFFECTS

SUMMARY – Lymphomas are very radiosensitive and radiotherapy (RT) was the first treatment modality that enabled cure. It is the most effective single modality for local control of lymphomas. However, as a local form of treatment, curative intention is only possible if all lymphoma tissue can be incorporated in the volume to be irradiated with the prescribed total irradiation dose. That is why RT is a single modality only in early stage of nodular lymphocyte predominance Hodgkin’s lymphoma and low grade non-Hodgkin’s lymphoma. In most patients, RT can be used as consolidation therapy after chemotherapy or as salvage after failure of chemotherapy. In the past two decades, irradiation techniques have been improved in order to spare critical tissues and reduce toxicity. Although effective, RT is a neglected modality of treatment because of the appearance of new drugs and fear of side effects after irradiation. Radiation has been shown to be effective in the treatment of all stages and forms of lymphoma. Study data are still mostly derived from patients that received supradiaphragmal RT; therefore, there is no agreement about the best management approach in patients with infradiaphragmal lymphoma.

An evidence-based review on the value of interim FDG-PET in assessing response to therapy in lymphoma

Assessing response to therapy in lymphoma is important for determining patients' prognosis, guiding subsequent treatment, and may be used as an outcome measure of prognostic and therapeutic trials. Traditionally, computed tomography was the mainstay for response assessment and was predominantly performed at the end of treatment, whereas the most recent guidelines propose ¹⁸F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) for this purpose. However, the value of FDG-PET performed during treatment (interim FDG-PET) is still a topic of debate. The purpose of this scientific communication is to provide an evidence-based overview of the value of interim FDG-PET in patients with lymphoma. The article first describes the development of imaging-based response assessment in lymphoma, the rationale and limitations of using FDG-PET for this purpose, and continues with the evidence-based clinical utility of interim FDG-PET in three major lymphoma subtypes (Hodgkin lymphoma, diffuse large B-cell lymphoma, and follicular lymphoma), and finishes with conclusions and recommendations for standard care and future research.

Impact of salvage treatment modalities in patients with positive FDG-PET/CT after R-CHOP chemotherapy for aggressive B-cell non-Hodgkin lymphoma

INTRODUCTION

To compare outcomes of different salvage treatment modalities in patients with aggressive B-cell non-Hodgkin lymphoma (NHL) who remain FDG-PET positive after R-CHOP chemotherapy. Existing data on these patients with FDG-PET primary refractory disease are limited.

METHODS

Patients with diffuse large B-cell lymphoma or grade 3 follicular lymphoma were retrospectively reviewed from the Prince of Wales Hospital databases. Eligibility criteria were: age≥18 years, treated with R-CHOP, with positive post-chemotherapy FDG-PET. Salvage treatment modalities were: radical radiotherapy (RT, dose≥30 Gy), high dose chemotherapy and autologous stem cell transplant (ASCT), or non-radical management. Survival was calculated from date of post-chemotherapy FDG-PET to last follow-up.

RESULTS

Twenty-six patients from 2003-2015 met the inclusion criteria. Median age was 60 (range 19-84). Most had adverse baseline features: 21 (81%) stage III-IV, 24 (92%) bulky disease and nine (35%) skeletal involvement. Characteristics of PET-positivity post-chemotherapy were single site in 16 (62%), sites of prior bulk in 24 of 24, skeletal sites in five of nine, and able to be encompassed by RT in 21 (81%). Salvage treatment was: radical RT in 17 (65%), ASCT in four (15%) and non-radical in five (20%). Median follow-up of surviving patients was 31 months. Kaplan-Meier estimates of 3-year PFS and OS were 41% and 52%, respectively. By salvage modality, 3-year PFS was 51% for RT, 25% for ASCT and 20% for non-radical treatment, (P = 0.453); 3-year OS was respectively 65%, 25% and 40% (P = 0.173).

CONCLUSION

Patients with FDG-PET positive disease after R-CHOP for aggressive B-cell NHL are salvageable with radiotherapy.

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".

Consolidation radiotherapy for advanced-stage aggressive B-cell non-Hodgkin lymphoma: A systematic review and meta-analysis

Patients with advanced aggressive B-cell non-Hodgkin lymphomas (NHL) are usually treated with rituximab in combination with chemotherapy. However, disease relapse rates are high. Radiotherapy (RT) has been shown to be efficacious in treating early-stage NHL but its role in advanced stage diseases is unclear. We performed a systematic review of randomized controlled trials (RCTs) comparing chemotherapy with RT to chemotherapy alone in patients with newly diagnosed advanced aggressive NHL. We searched online databases and pooled similar outcome estimates. For time-to-event outcomes, we estimated hazard ratios (HR) for overall survival (OS) and event-free survival (EFS) using the fixed-effect model. Two RCTs involving 254 patients met inclusion criteria. The trials were single-centre RCTs with follow-up period of five and ten years. Both trials were conducted in the pre-rituximab era. Patients treated with consolidation RT had better OS (HR for mortality 0.61; 95 % CI 0.38 to 0.97) and EFS (HR for mortality 0.67; 95 % CI 0.46 to 0.98) compared to those who received no RT. There was an apparent benefit of RT on local control (OR 0.09; 95 % CI 0.04 to 0.20); although this was estimated as a dichotomous rather than time-to-event outcome. Limited evidence shows benefits of consolidation RT in advanced aggressive NHL. However, we were not able to estimate the effect size with confidence due to small number of trials and sample size. We cannot recommend routine consolidation RT in advanced aggressive NHL. More RCTs with the inclusion of rituximab and PET-CT monitoring are needed.

Consolidative Radiotherapy to Residual Masses After Chemotherapy Is Associated With Improved Outcome in Diffuse Large B-Cell Lymphoma. A Retrospective, Population-Based Study

BACKGROUND

The role of consolidative radiotherapy (RT) in advanced diffuse large B-cell lymphoma (DLBCL) is not established.

PATIENTS AND METHODS

In a population-based retrospective analysis of patients with DLBCL in Western Norway during 2003 to 2008, 170 consecutive patients admitted to Haukeland University Hospital (HUS) and 94 to Stavanger University Hospital (SUS) were included. The mean age was 64 years (range, 17-95 years), 147 patients (56%) were male, 80 patients (30%) had stage I/II, 126 patients (48%) stage III/IV, and 57 patients (22%) had primary extranodal disease.

RESULTS

There were no differences between hospitals in patient characteristics, use of rituximab, number of chemotherapy courses or cumulative doses, or in distribution of response categories after chemotherapy. The use of RT was significantly different: 17 patients (23%) received RT at SUS and 92 patients (65%) at HUS (P < .001). For 219 patients with International Prognostic Index (IPI) score of 0 to 3, 5-year cancer-specific survival (CSS) was 67% at SUS and 81% at HUS (P = .012). For 73 patients with complete response after chemotherapy there were no differences in survival between patients with and without RT. For 138 patients with any residual mass after chemotherapy, there were highly significant differences in favor of receiving RT (n = 81) versus no RT (n = 57): 5-year CSS 89% versus 69% (P < .001), and 5-year overall survival 82% versus 59% (P = .005). The effect of RT on residual mass was evident in most subgroups, mainly in low to intermediate risk, but not in high-risk (IPI 4-5) patients.

CONCLUSION

With the limitations of a retrospective study, these data suggest that consolidative RT might improve survival in DLBCL patients with a residual mass after chemotherapy, also in advanced disease.

Treatment outcome of diffuse large B-cell lymphoma involving the head and neck: Two-institutional study for the significance of radiotherapy after R-CHOP chemotherapy

This study was performed to analyze the treatment outcome for diffuse large B-cell lymphoma (DLBCL) involving the head and neck and to evaluate the role of radiotherapy in the rituximab era. Fifty-six patients diagnosed with DLBCL involving the head and neck were assessed. All patients were treated with 6 cycles of rituximab, cyclophosphamide, adriamycin, vincristine, and prednisolone (R-CHOP). After chemotherapy, radiation was delivered to the head and neck area in a median dose of 36 Gy. Radiation was delivered using 3-dimensional radiotherapy (n  =  25) or intensity-modulated radiotherapy (n  =  31). Primary endpoints were relapse-free survival (RFS), overall survival (OS), and local control rate. After median follow-up time of 45 months, the 5-year RFS and OS rates were 72% and 61%, respectively. Fourteen (25%) of 56 patients relapsed; 1 had a local relapse, 11 had distant relapses, and 2 had both local and distant relapses. The final local control rate after radiotherapy was 94%. Age, performance status, international prognostic index score, and radiotherapy response were significant prognostic factors for both RFS and OS in the multivariate analysis. Incidence of acute grade 3 and 4 hematologic toxicity was 9% and 4%, respectively. Grade 3 nonhematologic toxicity occurred in 2 (4%) patients, and there was no grade 4 nonhematologic toxicity for the irradiated patients. Excellent local control and survival rates can be achieved with R-CHOP followed by radiotherapy in patients with DLBCL involving the head and neck. Treatment-related toxicity after the introduction of modern radiotherapy was acceptable and limited.

Male Breast Cancer as a Second Primary Cancer: Increased Risk Following Lymphoma

BACKGROUND

Male breast cancer (MBC) as a second primary cancer (SPC) has a known association with prior MBC. However, its association with non-breast index malignancies, relative to population risk, has not been previously reported.

MATERIALS AND METHODS

Using Surveillance, Epidemiology, and End Results program (9 catchment area) data, we identified MBCs diagnosed from 1973-2012 as their SPC. Information regarding the index malignancy was also obtained. Standardized incidence ratios (SIR) of MBC as SPC were estimated, along with incidence rates and trends. Kaplan-Meier curves were used to estimate survival.

RESULTS

Over a 38-year period, 464 MBCs were identified as SPC. The most common index malignancies were breast (SIR 30.86, 95% confidence interval [CI] 21.50-42.92, p < .001), lymphoma (SIR 1.58, 95% CI 1.08-2.22, p = .014), melanoma (SIR 1.26, 95% CI 0.80-1.89), urinary (SIR 1.05, 95% CI 0.74-1.43), colorectal (SIR 0.94, 95% CI 0.69-1.24), and prostate (SIR 0.93 95% CI 0.81-1.07). Apart from the known association with prior breast cancer, the only significant association was with lymphoma as an index cancer, although not significant with a Bonferroni correction. From 1975-2012, incidence of breast cancer as a first cancer increased at an annual percentage change of 1.3% while breast cancer as a SPC increased at 4.7% (both p values < .001).

CONCLUSION

Male breast cancer as a SPC has increased markedly over 4 decades. Men with a history of lymphoma may experience higher-than-expected rates of breast SPC. These observations warrant further research, and suggest possible etiologic connections with disease biology, prior therapy, or genetics.

IMPLICATIONS FOR PRACTICE

This study reports that men are presenting more frequently to the clinic with breast cancer, both as an initial cancer and as a second cancer following an earlier malignancy. We also report the novel observation that men who survive lymphoma are at increased risk of developing a subsequent breast cancer. Further work is needed to better understand possible treatment or biologic causes of this association. More immediately, these findings suggest the need for heightened vigilance for male breast cancer overall and, in particular, for male lymphoma survivors.

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.

Analysis of prognostic value of complete response by PET-CT and further stratification by clinical and biological markers in DLBCL patients

Positron emission tomography-computed tomography (PET-CT) is performed as the standard method for response assessment of diffuse large B cell lymphoma (DLBCL) patients. However, a substantial proportion of patients experience relapse even if they have achieved complete response (CR) defined by PET-CT. We validated the prognostic value of CR by PET-CT and applied the National Comprehensive Cancer Network-International Prognostic Index (NCCN-IPI) and cell of origin (COO) to patients with CR by PET-CT to evaluate their additional predictive ability for survival outcomes. We retrospectively analyzed DLBCL patients who were treated with R-CHOP or an R-CHOP-like regimen and who achieved CR by PET-CT or CT only. A total of 185 patients were analyzed: 114 patients achieved CR by PET-CT and 71 patients by CT only. Patients with CR by PET-CT had significantly better overall survival (OS) than those with CR by CT (5-year OS, 87.5 vs. 62.4%, P = 0.003). Patients with high risk according to the NCCN-IPI had a dismal outcome despite achieving CR by PET-CT (5-year OS, 61.8%). In contrast, low-, low-intermediate-, and high-intermediate-risk patients had excellent outcomes (5-year OS, 100, 89.7, and 93.5%, respectively). Among patients with CR by PET-CT, patients with germinal center B cell (GCB) DLBCL (n = 40) had significantly better survival than those with non-GCB DLBCL (n = 57) (5-year OS, 96.9 vs. 75.5%, P = 0.039). We demonstrated that CR by PET-CT was a better predictor of survival outcomes than CR by CT only. The NCCN-IPI and COO subtypes could identify a subpopulation of poor-risk patients among those who achieved CR by PET-CT.

Radioimmunotherapy with (131)I-rituximab as consolidation therapy for patients with diffuse large B-cell lymphoma

PURPOSE

The aim of this study was to assess the clinical activity and toxicity of (131)I-rituximab as consolidation therapy for patients with diffuse large B-cell lymphoma (DLBCL) who were treated with R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin, and prednisolone).

METHODS

Patients who had been diagnosed with advanced stage (Ann Arbor III or IV) or bulky stage II DLBCL and achieved complete or partial response after six to eight cycles of R-CHOP were enrolled.

RESULTS

A total of 16 patients were enrolled and treated with a single dose of (131)I-rituximab as consolidation therapy after the completion of six or eight cycles of R-CHOP between December 2005 and June 2011. This trial was terminated before the scheduled enrollment owing to low recruitment. Among the 16 patients who were treated with consolidative (131)I-rituximab, 6 achieved complete response (CR) after three cycles of R-CHOP, and another 9 patients further achieved CR after the completion of six or eight cycles of R-CHOP. During the median follow-up period of 73 months, only four patients (25 %) experienced relapse. Two-year relapse-free survival was 88 %, and 5-year relapse-free survival was 81 %. Grade 3 or 4 treatment-related toxicity occurred in four patients and included neutropenia and thrombocytopenia.

CONCLUSIONS

(131)I-rituximab showed promising efficacy as consolidation treatment for patients with DLBCL. A future randomized phase III study to confirm our results is warranted.

Prognostic value of interim FDG-PET in R-CHOP-treated diffuse large B-cell lymphoma: Systematic review and meta-analysis

This study aimed to systematically review and meta-analyze the prognostic value of interim (18)F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP). MEDLINE and EMBASE were systematically searched for suitable studies. Included studies were methodologically appraised, and results were summarized both descriptively and meta-analytically. Nine studies, comprising a total of 996 R-CHOP-treated DLBCL patients, were included. Overall, studies were of moderate methodological quality. The area under the summary receiver operating curve (AUC) of interim FDG-PET in predicting treatment failure and death were 0.651 and 0.817, respectively. There was no heterogeneity in diagnostic odds ratios across available studies (I(2)=0.0%). At multivariable analysis, 2 studies reported interim FDG-PET to have independent prognostic value in addition to the International Prognostic Index (IPI) in predicting treatment failure, whereas 3 studies reported that this was not the case. One study reported interim FDG-PET to have independent prognostic value in addition to the IPI in predicting death, whereas 2 studies reported that this was not the case. In conclusion, interim FDG-PET in R-CHOP-treated DLBCL has some correlation with outcome, but its prognostic value is homogeneously suboptimal across studies and it has not consistently proven to surpass the prognostic potential of the IPI. Moreover, there is a lack of studies that compared interim FDG-PET to the recently developed and superior National Comprehensive Cancer Network-IPI. Therefore, at present there is no scientific base to support the clinical use of interim FDG-PET in R-CHOP-treated DLBCL.

Is Radiation Necessary for Treatment of Non-Hodgkin's Lymphoma of Bone? Clinical Results With Contemporary Therapy

BACKGROUND

Non-Hodgkin's lymphoma (NHL) of bone is a rare musculoskeletal malignancy accounting for fewer than 7% of bone cancers. Traditionally, we have treated patients who have NHL of bone with chemotherapy and radiation therapy, but the role of radiotherapy in disease management and patient functional outcomes after treatment have not been well studied. We investigated the survival advantage of radiotherapy in a large cohort of patients with NHL of bone and assessed associated patient complications of radiotherapy.

QUESTIONS/PURPOSES

The objective of this study was to compare patients treated for NHL of bone with and without radiation in terms of (1) overall survival; (2) pretreatment complications; (3) posttreatment complications; and (4) functional outcomes using the Musculoskeletal Tumor Society (MSTS) score.

METHODS

A retrospective analysis of all patients with biopsy-proven NHL of bone diagnosed at our institution between 1985 and 2013 was undertaken; 70 patients met our criteria for inclusion with minimum followup of 6 months (median, 55 months; range, 10-219 months). Overall survival at 5 and 10 years was estimated and compared between two groups of patients: one group treated with systemic therapy alone (chemotherapy, rituximab; 46 patients [66%]) and the other with combined modality therapy (systemic therapy and radiotherapy; 24 patients [34%]). During the period in question, indications for radiotherapy included bulky disease, an abbreviated course of systemic therapy, and an incomplete response to systemic therapy. Patients not meeting these criteria generally received systemic therapy alone. With the available sample size, it was estimated that a difference in survival of approximately 30% would have to be present for detection with 80% power (α = 0.05, β = 0.2, n = 70, Δ = 30%). Pretreatment and posttreatment complications occurring in both patient groups were retrospectively reviewed with special emphasis on fracture healing after treatment. MSTS scores were obtained for 45 patients with appendicular tumors at a median followup of 42 months (range, 10-215 months).

RESULTS

With the data available, no difference in Kaplan-Meier survivorship was observed between patients treated with and without radiation at 5 years (98%; 95% confidence interval [CI], 93%-100% versus 95%; 95% CI, 85%-100%; p = 0.281). Patients who were treated with radiation were more likely to experience problems with fracture healing (relative risk [RR], 12.8; 95% CI, 1.8-89.8; p = 0.01). Similarly, patients treated with radiation were at a higher risk for fracture in the posttreatment period (five of 24 versus no radiation zero of 46; RR, 20.7; 95% CI, 1.2-359.0; p = 0.0375). MSTS scores were poorer in patients treated with radiation (75% versus 91%; p = 0.034) attributable in part to a higher incidence of bony complications in this group after treatment.

CONCLUSIONS

Based on the numbers of patients in our study, we could not demonstrate a survival advantage with radiation use. Rather, radiotherapy may be associated with orthopaedic complications occurring during and after treatment. Larger, prospective studies are necessary to definitively establish whether radiation is necessary for the treatment of patients with lymphoma of bone.

LEVEL OF EVIDENCE

Level III, therapeutic study.

ACR Appropriateness Criteria® Diffuse Large B-Cell Lymphoma

The management of diffuse large B-cell lymphoma depends on the initial diagnosis including molecular and immunophenotypic characteristics, Ann Arbor staging, and International Prognostic Index (IPI score). Treatment approaches with different chemotherapy regimens used is discussed in detail. The role of radiation as a consolidation is discussed including: (1) the prerituximab randomized trials that challenged the role of radiation, (2) recent prospective studies (UNFOLDER/RICOVER-60), and (3) retrospective studies; the last 2 showed a potential benefit of radiation both for early and advanced stage. The document also discusses the role of positron emission tomography/computed tomography for predicting outcome and potentially guiding therapy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

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

The role of consolidative radiotherapy (RT) in patients ≥60 years old with DLBCL in the rituximab era is controversial. We examined the impact on disease control and overall survival by the addition of consolidative RT after completion of chemotherapy, while adjusting for known adverse risk factors. Retrospective chart review from 2004 to 2012 of 83 consecutive patients ≥60 years old with DLBCL treated in the rituximab era, 68 of which had a complete response to chemotherapy, was performed. Amongst patients with a complete response, consolidative RT use was associated with 100% 5-year local control, improved progression-free survival (p = 0.047), and a trend for overall survival (p = .098) on multivariate analysis. Amongst all patients, the use of consolidative RT was associated with improved overall survival (p = 0.03). The use of consolidative RT should be considered for patients ≥60 years old independent of stage and response to chemotherapy.

The importance of radiotherapy on diffuse large B cell lymphoma treatment: a current review

Diffuse large B cell lymphoma is recognized as a heterogeneous group of hematological malignancies; two main subtypes germinal center B and activated B cells are well defined although 15% of patients remain with unclassifiable disease. R-CHOP treatment has proven to provide very effective results in limited or advanced stage of the disease. However, treatment solely involving R-CHOP submits the patient to possible chemotherapy-induced toxicities, which may be avoided with the use of radiotherapy. Patients with early stage localized disease or who are particularly unresponsive to chemotherapy may be more suitable for mixed modality treatment with R-CHOP and consolidative radiotherapy. Although radiotherapy is being slowly phased out by other treatment strategies including chemotherapy and therapeutic drugs, it is still a highly important method of treatment. The different forms of radiotherapy can be used alongside these "new-age" treatment strategies to further improve prognostic outcomes and overall survival rates. The establishment of radiotherapy as a treatment strategy provides a highly beneficial prognostic advantage in early stage, localized disease.

Extranodal lymphoma of the posterior auricle

BACKGROUND

Malignant lymphoma of the head and neck represents the most common non-epithelial head and neck cancer. Approximately one third of these occur outside of lymph nodes and have been described in most sub-sites of the head and neck.

CASE

We describe a case of an elderly woman who presented with a non-healing ulcer on the posterior aspect of her right pinna. Biopsy was performed and found to be a diffuse large B-cell lymphoma. This patient was treated with chemotherapy and local radiation therapy.

CONCLUSIONS

This is the first reported case of an extranodal lymphoma affecting the auricle. We review lymphoma of the head and neck and the role of the otolaryngologist.

Predictors of local recurrence after rituximab-based chemotherapy alone in stage III and IV diffuse large B-cell lymphoma: guiding decisions for consolidative radiation

PURPOSE

The role of consolidative radiation therapy (RT) for stage III and IV diffuse large B-cell lymphoma (DLBCL) in the era of rituximab is not well defined. There is evidence that some patients with bulky disease may benefit, but patient selection criteria are not well established. We sought to identify a subset of patients who experienced a high local failure rate after receiving rituximab-based chemotherapy alone and hence may benefit from the addition of consolidative RT.

METHODS AND MATERIALS

Two hundred eleven patients with stage III and IV DLBCL treated between August 1999 and January 2012 were reviewed. Of these, 89 had a complete response to systemic therapy including rituximab and received no initial RT. Kaplan-Meier analysis and Cox proportional hazards regression were performed, with local recurrence (LR) as the primary outcome.

RESULTS

The median follow-up time was 43.9 months. Fifty percent of patients experienced LR at 5 years. In multivariate analysis, tumor ≥ 5 cm and stage III disease were associated with increased risk of LR. The 5-year LR-free survival was 47.4% for patients with ≥ 5-cm lesions versus 74.7% for patients with <5-cm lesions (P=.01). In patients with <5-cm tumors, the maximum standardized uptake value (SUVmax) was ≥ 15 in all patients with LR. The 5-year LR-free survival was 100% in SUV<15 versus 68.8% in SUV ≥ 15 (P=.10).

CONCLUSIONS

Advanced-stage DLBCL patients with stage III disease or with disease ≥ 5 cm appear to be at an increased risk for LR. Patients with <5-cm disease and SUVmax ≥ 15 may be at higher risk for LR. These patients may benefit from consolidative RT after chemoimmunotherapy.

Approach to therapy of diffuse large B-cell lymphoma in the elderly: the International Society of Geriatric Oncology (SIOG) expert position commentary

Diffuse large B-cell lymphoma (DLBCL) is a treatable and potentially curable malignancy that is increasing in prevalence in the elderly. Until recently, older patients with this malignancy were under-represented on clinical treatment trials, so optimal therapeutic approaches for these patients were generally extrapolated from the treatment of younger patients with this disorder. Because of heightened toxicity concerns, older patients were sometimes given reduced dose therapy, potentially negatively impacting outcome. Geriatric considerations including functional status and comorbidities often were not accounted for in treatment decisions. Because of these issues as well as the lack of treatment guidelines for the elderly population, the International Society of Geriatric Oncology convened an expert panel to review DLBCL treatment in the elderly and develop consensus guidelines for therapeutic approaches in this patient population. The following treatment guidelines address initial DLBCL therapy, in both limited and advanced stage disease, as well as approaches to the relapsed and refractory patient.

The Role of Consolidative Radiotherapy after a Complete Response to Chemotherapy in the Treatment of Diffuse Large B-Cell Lymphoma in the Rituximab Era: Results from a Systematic Review with a Meta-Analysis

BACKGROUND

The current standard therapy for patients with diffuse large B-cell lymphoma (DLBCL) is rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (RCHOP). The role of radiotherapy (RT) after complete response (CR) to RCHOP in patients with DLBCL remains unclear. This systematic review with a meta-analysis is an attempt to evaluate this role.

METHODS

Studies that evaluated RT versus no-RT after CR to RCHOP for DLBCL patients were searched in databases. Hazard ratios (HR) with their respective 95% confidence intervals (CI) were calculated using a random-effects model.

RESULTS

A total of 4 qualified retrospective studies (633 patients) were included in this review. The results suggested that RT improved overall survival (OS; HR 0.33, 95% CI 0.14-0.77) and progression-free/event-free survival (PFS/EFS; HR 0.24, 95% CI 0.11-0.50) in all patients compared with no-RT. In a subgroup analysis of patients with stage III-IV DLBCL, RT improved PFS/EFS (HR 0.19, 95% CI 0.07-0.51) and local control (HR 0.12, 95% CI 0.03-0.44), with a trend of improving OS (HR 0.35, 95% CI 0.12-1.05).

CONCLUSION

Consolidation RT could significantly improve outcomes of DLBCL patients who achieved a CR to RCHOP. However, the significance of these results was limited by these retrospective data. Further investigation of the role of consolidation RT in the rituximab era is needed.