What is the optimal management of early-stage low-grade follicular lymphoma in the modern era?

Impact of age on long-term relative survival benefit of radiotherapy for early-stage grade I-II follicular lymphoma from the SEER database (2000-2015)

The aim of this study was to investigate the effect of age on long-term mortality and net survival benefit of radiotherapy (RT) for early-stage grade I-II FL. Five thousand three hundred and five patients with early-stage grade I-II FL in the SEER database (2000-2015) were identified. Primary therapy included RT alone (RT, 20.7%), chemotherapy alone (CT, 27.6%), combined modality therapy (CMT, 5.9%), and observation (45.8%). Inverse probability of treatment weighting (IPTW) was conducted to balance the treatment arms. Relative survival (RS), the standardized mortality ratio (SMR), and transformed Cox regression were used to compare survival differences between treatments. RT with or without CT had significantly higher 10-year OS (approximately 78%) and RS (>95%), but lower SMR (1.47-1.76), compared with CT (67.8%; 86.3%; 2.35; ps < .001), observation (70.2%; 91.2%; 1.82; ps < .05). RT was an independent predictor of better OS and RS in multivariate analyses (p < .001). No significant interaction between age and RT was identified for RS (Pinteraction = .509) or OS (Pinteraction = .769), indicating similar survival benefits across all-ages patients. RT was associated with long-term OS and net survival benefits in patients with early-stage grade I-II FL, irrespective of age.HighlightsThe pattern and incidence of mortality varied by age-group as elderly patients often die of other diseases other than FL beyond 5 years.Radiotherapy was associated with higher long-term OS/RS and better SMR compared with other approaches, regardless of age.

Personalised therapy in follicular lymphoma - is the dial turning?

Follicular lymphoma is the most common indolent lymphoma accounting for approximately 20%-25% of all new non-Hodgkin lymphoma diagnoses in western countries. Whilst outcomes are mostly favorable, the spectrum of clinical phenotypes includes high-risk groups with significantly inferior outcomes. This review discusses recent updates in risk stratification and treatment approaches from upfront treatment for limited and advanced stage follicular lymphoma to the growing options for relapsed, refractory disease with perspectives on how to approach this from a personalized lens. Notable gaps remain on how one can precisely and prospectively select optimal treatment for patients based on varying risks, with an anticipation that an increased understanding of the biology of these different phenotypes and increasing refinement of imaging- and biomarker-based tools will, in time, allow these gaps to be closed.

Evaluating patterns of care for early-stage low-grade follicular lymphoma in the rituximab era

Radiotherapy (RT) utilization for early-stage, low-grade follicular lymphoma (FL) is low despite treatment guideline recommendations. We compare treatment trends for early-stage FL in the era of involved-site RT and rituximab. We identified 11,645 patients in the National Cancer Database (NCDB) with stage I-II, grade 1-2 nodal or extranodal FL diagnosed 2011-2017, with median follow-up of 44 months. From 2011 to 2017, RT utilization rates decreased from 33.4% to 22.4%, observation decreased from 65.3% to 49.7%, chemoimmunotherapy increased from 0.5% to 15.0%, immuno-monotherapy increased from 0.6% to 10.2%, and RT + systemic therapy increased from 0.6% to 2.5%. RT utilization remains low in the involved-site RT and rituximab era.

[Hematological pathologies: the most successful model of de-escalation in radiotherapy]

The proportion of patients irradiated in the context of malignant hematological pathologies decreased over the last decades. The main causes are the late side effects of the historical series and the new therapeutic strategies aiming to relay radiotherapy to the rank of option. At the same time, radiotherapy has been modernised, target volumes and total doses have been drastically reduced. Hodgkin's lymphomas, indolent follicular lymphomas and primary cerebral lymphomas are the main witnesses of this therapeutic deflation.

Is Radiotherapy Cost-effective in the PET/CT-era for Early-Stage Favorable Hodgkin's Lymphoma with Alternative Payment Models?

INTRODUCTION

Despite multiple randomized trials, there remains variation in practice regarding the most effective treatment for early-stage favorable-risk Hodgkin's lymphoma. With increasing emphasis on alternative payment models, we investigate the cost effectiveness of chemotherapy alone versus combined modality therapy (CMT).

METHODS AND MATERIALS

A Markov model was formed to compared 2 cycles of ABVD to 2 cycles of ABVD followed by 20 Gy in 10 fractions involved-site radiotherapy (CMT). Modalities were compared using the incremental cost-effectiveness ratio (ICER), with effectiveness measured in quality-adjusted life years (QALYs) and evaluated with a willingness to pay threshold of $100,000 per QALY gained.

RESULTS

Base case analysis showed that CMT is cost effective compared to ABVD alone, with an ICER of $8,028 per QALY gained, and an incremental cost of $236 gaining 0.029 QALYs. On sensitivity analyses, results were most sensitive to changes in recurrence rates, if recurrence rate differences were ≥6% CMT was cost effective.

CONCLUSION

CMT is a cost-effective strategy for early-stage favorable-risk Hodgkin's lymphoma based on currently available evidence. However, small variations in recurrence rate estimates dramatically impact strategy cost-effectiveness.

Effectiveness and tolerability of radiotherapy for patients with indolent non-Hodgkin's lymphoma: a monocenter analysis

To analyze the effectiveness and toxicities of radiotherapy in indolent non-Hodgkin's lymphoma (iNHL) patients treated in our institution. Patients with iNHL treated with radiotherapy between 1999 and 2016 were included. The primary endpoint was progression-free survival (PFS). Secondary endpoints were local control (LC), overall survival (OS) and toxicities. PFS, LC, and OS were analyzed using Kaplan-Meier method. Log-rank test was used to investigate the differences between subgroups. Cox proportional hazard model was used for univariate continuous analysis. Seventy-five patients were identified in our institutional database between 1999 and 2016. Fifty-eight (77.3%) had stage I after Ann-Arbor and 17 patients (22.7%) had stage II. The median follow-up was 87 months (95% CI 72-102 months). Median single dose per fraction was 2.0 Gy (range 1.5-2 Gy) and median total dose was 30.6 Gy (range 16-45 Gy). Radiotherapy was performed in 2D (n = 10; 13.3%), 3D (n = 63; 84.0%) and VMAT (n = 2; 2.7%) techniques, respectively. The median PFS was 14.0 years (95% CI 8.3-19.7 years). The estimated PFS after 5 and 10 years were 73.0% and 65.5% in Kaplan-Meier analysis, respectively. The 5- and 10-year LC were 94.9% and 92.3%, respectively. The 5- and 10-year OS were 88.6% and 73.9%. In univariate analyses of PFS, younger patients (≤ 60 years old) had significantly superior PFS to those older than 60 years old (5-year PFS 81.9% vs. 65.1%, p = 0.021). Dose escalation > 36.0 Gy had no prognostic influence in term of PFS (p = 0.425). Extranodal involvement, stage and histology had no prognostic impact on PFS. Depending on the site of lymphomas, the most common acute side effects were: dermatitis CTCAE° I-II (8.0%), xerostomia CTC° I (8.0%), cataract CTC° I (12.0%) and dry eyes CTC° I-II (14.6%). No adverse event CTC° III was reported. Most acute side effects recovered at 3 to 6 months after radiotherapy except for CTC° I cataract and xerostomia. Local Radiotherapy was highly effective for treatment of early stage iNHL with no serious side effects in our cohort. The most acute CTCAE° I-II side effects recovered 3 to 6 months later. Technique advances seem to have further improved effectiveness and tolerability of radiotherapy.Trial registration: Local ethics committee of Ludwig-Maximilian-University (LMU) Munich approved this retrospective analysis on the May 7th, 2019 (Nr. 19-137).

Epidemiology of diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) in the United States and Western Europe: population-level projections for 2020-2025

Diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) treatments have been rapidly evolving for patients treated in later lines of therapy (LoT). Country-specific cancer registry data for the US and Western Europe (WE) were combined with physician survey results to project the incidence, prevalence, and number of DLBCL and FL patients eligible for and treated by LoT between 2020 and 2025. The total number of incidents and prevalent cases of DLBCL and FL is expected to increase between 2020 and 2025 in the US and WE. 56% and 53% of the third line plus (3L+) eligible DLBCL patients and 60% and 55% of eligible FL patients initiated treatment in the US and WE, respectively. Further research is warranted to understand the reasons behind the high proportion of treatment eligible patients who do not initiate treatment, and potential differences between countries, especially in the 3L + settings.

A cost-effectiveness analysis of front-line treatment strategies in early-stage follicular lymphoma

Recent data suggest the use of radiotherapy alone (RT) in Early-Stage Follicular Lymphoma is declining. Cost-effectiveness analysis of treatments has not been performed. We constructed a partitioning model (15-year horizon) to compare RT, combined-modality therapy (CMT) and immunochemotherapy with rituximab maintenance (ICT + RM) from a PET-staged cohort from the Australian Lymphoma Alliance. Lifetime direct health care costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) were calculated. AUD $75,000 was defined as the willingness-to-pay threshold (WTP). The direct healthcare costs were: RT $12,791, CMT $29,391 and ICT + RM $42,644. Compared with RT, CMT demonstrated minimal improvement in QALYs (+0.01) and an ICER well above the WTP threshold ($1,535,488). Compared with RT, ICT + RM demonstrated an improvement in QALYs (+0.41) with an ICER of $73,319. Modeling a 25% cost reduction with a rituximab biosimilar led to further ICER reductions with ICT + RM ($52,476). ICT + RM is cost-effective in early-stage FL from the Australian taxpayer perspective.

Treatments and Outcomes in Stage I Extranodal Marginal Zone Lymphoma in the United States

Simple Summary

Extranodal marginal zone lymphoma (EMZL) is a rare disease commonly diagnosed at an early stage and remains localized for prolonged periods of time. This unique characteristic makes the use of local therapies, such as radiation therapy (RT), the preferred approach. Excellent results were previously reported implementing RT; however, majority of these studies included a small number of patients, and treatment patterns in the United States are presently unknown. Furthermore, EMZL may arise in various organs, and whether the survival is similar at different locations is unclear. In the present study, we assessed the Surveillance, Epidemiology, and End Results (SEER) database aiming to examine management and survival of localized EMZL. While differences in survival were observed by primary disease location, similar survival was observed in RT-treated stage I EMZL patients and general U.S. population matched by sex, age, and calendar year.

Abstract

A considerable number of patients with extranodal marginal zone lymphoma (EMZL) are diagnosed with stage I disease. Information on treatments and survival by primary location remains limited. We extracted data from the Surveillance, Epidemiology, and End Results (SEER) database to assess treatment, primary location, and survival of patients with stage I EMZL. Results show that 7961 patients met inclusion criteria. Observation (no treatment) was the most common approach (31%) followed by radiation therapy (RT, 23%). The median overall survival (OS) was 17.3 years (95%CI 16.3 to 18.3). Shorter survival was observed in patients with stage I EMZL compared to expected survival in a cohort derived from the general U.S. population matched by sex, age, and calendar year at diagnosis. However, similar survival was observed in RT-treated patients. We identified age ≥ 60 years (SHR = 4.00, 95%CI 3.10–5.15; p < 0.001), higher grade transformation (SHR = 4.63, 95%CI 3.29–6.52; p < 0.001), and primary lung EMZL (SHR = 1.44, 95%CI 1.05–1.96; p = 0.022) as factors associated with shorter lymphoma-specific survival (LSS). Conversely, primary skin location (SHR = 0.50, 95%CI 0.33–0.77; p = 0.002) was associated with longer LSS. Our results support the use of RT as the preferred approach in localized EMZL.

Stage-specific trends in primary therapy and survival in follicular lymphoma: a nationwide population-based analysis in the Netherlands, 1989-2016

We assessed stage-specific trends in primary therapy and relative survival among adult follicular lymphoma (FL) patients diagnosed in the Netherlands between 1989-2016 (N = 12,372; median age, 62 years; and 21% stage I disease). Patients were stratified by disease stage and subsequently categorized into four calendar periods (1989-1995, 1996-2002, 2003-2008, and 2009-2016) and three age groups (18-60, 61-70, and >70 years). The use of radiotherapy in stage I FL remained relatively stable over time and across the three age groups (i.e., 66%, 54%, and 49% in 2009-2016, respectively). In stage II-IV FL, the start of chemotherapy within 12 months post-diagnosis decreased over time, indicating a broader application of a watch-and-wait approach. Relative survival improved considerably over time, especially since 2003 when rituximab was introduced in the Netherlands, and for stage III-IV FL patients and older age groups. Five-year relative survival for patients with stage I-II versus stage III-IV FL in the period 2009-2016 was 96% versus 90%, 93% versus 83%, and 92% versus 68% across the three age groups, respectively. Collectively, the improvement in survival since 2003 is accounted for by advances in FL management, particularly the implementation of rituximab. There remains, however, room for improvement among elderly stage III-IV FL patients.

How to manage early-stage follicular lymphoma

INTRODUCTION

Early-stage follicular lymphoma (FL) is characterized by good prognosis and can be cured with involved-field radiotherapy (IF-RT) in most cases. PET scan is a milestone of diagnostic work-up, with the aim of identifying a truly localized disease; however, staging in most of the studies was without PET.

AREAS COVERED

We have searched in MEDLINE (inclusive dates 1994-2020) data about localized FL management. While high-quality evidence is lacking, current guidelines recommend IFRT or involved-site RT as first-line treatment in limited stages FL. Since a significant proportion of disease relapse occurred in non-irradiated areas, it has been hypothesized that occult disease could be present at diagnosis and could persist after RT, contributing to relapse. Available treatment options include watch-and-wait, chemotherapy, RT plus chemo- or chemo-immunotherapy, and RT combined with rituximab (R).

EXPERT OPINION

RT combined with chemotherapy could increase PFS, but a clear OS benefit is lacking and toxic effects could be unacceptable. A promising strategy is represented by R combined with IF-RT, with low relapse rate outside the radiation fields and without the toxicity reported with chemotherapy. The study of prognostic factors in PET-staged patients, the reduction of RT fields and doses, and a response-adapted strategy represent new perspectives to investigate.

Oncological outcome and recurrence pattern analysis after involved-field irradiation in combination with rituximab for early-stage nodal and extranodal follicular lymphoma

Purpose

Combined radioimmunotherapy (RIT) in follicular lymphomas (FL) has shown promising treatment efficacy in the Mabthera® and Involved field Radiation (MIR) study. Aim of this study was to analyze treatment efficacy and recurrence patterns after RIT in early-stage nodal and extranodal FL.

Methods

We reviewed 107 patients who were treated with combined RIT in two centers. Treatment consisted of 4 × rituximab followed by RIT with 4 × rituximab and involved field (IF) radiotherapy with 30/40 Gy. Median follow-up period was 71 months. In contrast to the MIR study, extranodal involvement and grade 3A histology were included in the analysis.

Results

Extranodal involvement and grade 3A histology were present in 21.8% and 13.1%, respectively. Overall response rate (ORR) after 4 × rituximab, after completion of RIT, and after 6 months was 78.1%, 98.8%, and 98.8%, respectively, with increasing rates of complete remissions (CR). Predictive factors associated with superior PFS were tumor size, completely excised lymphomas, and response to first 4 × rituximab. 5‑year PFS rate was 87.3%, with mostly outfield recurrences (94.1%). Second-line treatment was effective, with 53.3% CR and 46.7% partial remissions (PR). 5‑year OS was 98.1%. RIT was tolerated well, with mainly grade 1–2 acute side effects.

Conclusion

The real-world efficacy of RIT is comparable with the results of the MIR study. Additionally, this analysis shows that extranodal involvement and grade 3A histology are not associated with inferior PFS.

Controversies in the Treatment of Follicular Lymphoma

The overall prognosis of patients with follicular lymphoma has substantially improved over the last decades with a 10-year overall survival of around 80% for the majority of patients. However, for most patients follicular lymphoma it is still a relapsing and remitting disease. Furthermore, certain subsets of patients still have much shorter survival. Currently, there is no established standard how to treat high-risk follicular lymphoma. With advances in the understanding of the biology and pathogenesis of B cell malignancies, a plethora of new compounds have been investigated in FL. These compounds have the potential to increase efficacy if added to current regimens or even replace them. The implementation of these compounds in treatment algorithms is another unsolved issue. This overview highlights major controversies in the treatment of follicular lymphoma and discusses the most recent and relevant clinical trials.

Patient-level Factors Associated With the Initial Management of Older Adults Diagnosed With Follicular Lymphoma: A Surveillance, Epidemiology, and End Results-Medicare Analysis

INTRODUCTION

We evaluated patient-level factors associated with the initial management of older adults diagnosed with follicular lymphoma (FL).

MATERIALS AND METHODS

Using linked Surveillance, Epidemiology, and End Results-Medicare (SEER-Medicare) data; we identified 11,500 beneficiaries aged ≥ 66 years, diagnosed with FL between 2000 and 2013. A logistic regression model was used to estimate adjusted odds ratios (AORs) for factors associated with the receipt of active treatment versus watchful waiting (WW) as an initial management strategy. A multinomial logistic regression model was used to predict factors associated with receipt of specific active treatments, namely chemoimmunotherapy, rituximab monotherapy, chemotherapy, or radiation as compared with WW.

RESULTS

Overall, the initial management strategies adopted were WW (49%), chemoimmunotherapy (25%), radiation (10%), rituximab monotherapy (9%), and chemotherapy (7%). In reference to WW, grade III FL (AOR, 2.21; 95% confidence interval [CI], 1.99-2.46), increasing disease stage (Stage IV AOR, 1.80; 95% CI, 1.62-2.00), and use of preventive services (AOR, 1.18; 95% CI, 1.07-1.30) were associated with increased odds of active treatment receipt. Age > 80 years (AOR, 0.79; 95% CI, 0.71-0.87), Non-Hispanic African-American race (AOR, 0.64; 95% CI, 0.50-0.80), and state buy-in coverage (AOR, 0.81; 95% CI, 0.70-0.94) were associated with decreased odds of active treatment receipt. In reference to WW, the multinomial logistic regression model displayed differences in the receipt of rituximab-based therapies by age and comorbidity burden. Non-Hispanic African-American race and state buy-in coverage were associated with decreased odds of receiving rituximab-based therapies.

CONCLUSION

The present analysis identifies disparities in the initial management of older adults with FL owing to race and socioeconomic status. Future research should examine implications for subsequent treatment and health outcomes.

Outcomes of stage I/II follicular lymphoma in the PET era: an international study from the Australian Lymphoma Alliance

Management practices in early-stage (I/II) follicular lymphoma (FL) are variable and include radiation (RT), systemic therapy, or combined modality therapy (CMT). There is a paucity of data regarding maintenance rituximab in this cohort. We conducted an international retrospective study of patients with newly diagnosed early-stage FL staged with positron emission tomography (PET)-computed tomography and bone marrow biopsy. Three hundred sixty-five patients (stage I, n = 221), median age 63 years, treated from 2005-2017 were included, with a median follow-up of 45 months. Management included watchful waiting (WW; n = 85) and active treatment (n = 280). The latter consisted of RT alone (n = 171) or systemic therapy (immunochemotherapy [n = 63] or CMT [n = 46]). Forty-nine systemically treated patients received maintenance rituximab; 72.7% of stage I patients received RT alone, compared to 42.6% with stage II (P < .001). Active therapies yielded comparable overall response rates (P = .87). RT alone and systemic therapy without maintenance rituximab yielded similar progression-free survival (PFS) (hazard ratio [HR], 1.32; 95% confidence interval [CI], 0.77-2.34; P = .96). Maintenance rituximab improved PFS (HR, 0.24; 95% CI, 0.095-0.64; P = .017). The incidence of transformation was lower with systemic therapy compared to RT or WW (HR, 0.20; 95% CI, 0.070-0.61; P = .034). Overall survival was similar among all practices, including WW (P = .40). In the largest comparative assessment of management practices in the modern era, variable practices each resulted in similar excellent outcomes. Randomized studies are required to determine the optimal treatment in early-stage FL.

Rural and urban patients with diffuse large B-cell and follicular lymphoma experience reduced overall survival: a National Cancer DataBase study

We examined 83,108 patients with diffuse large B-cell lymphoma (DLBCL) and 43,393 patients with follicular lymphoma (FL) to investigate disparities related to geographic population density, stratified as rural, urban, or metropolitan. We found that urban and rural patients less commonly had private insurance and high socioeconomic status. Urban and rural DLBCL patients were more likely to receive treatment within 14 days of diagnosis (OR 0.93, 95% confidence interval [CI] 0.89-0.98; and OR 0.81, 95% CI 0.72-0.91) while urban FL patients were more likely to have treatment >14 days after diagnosis (OR 1.08, 95% CI 1.01-1.16). Multivariable analyses demonstrated that rural and urban patients had worse overall survival with DLBCL (hazard ratio [HR] 1.09; 95% CI 1-1.19 and HR 1.08; 95% CI 1.04-1.11) and FL (HR 1.11; 95% CI 1.04-1.18 and HR 1.2; 95% CI 1.02-1.41), respectively, suggesting needs for focused study and interventions for these populations.

Additional therapy improves outcomes in completely resected, limited-stage follicular lymphoma

Patients with early-stage nodal follicular lymphoma (FL) may be rendered free of detectable disease by a diagnostic excisional biopsy. We reviewed the management and outcomes of 48 patients with FL, diagnosed from 2003-2013, treated at a single institution. The primary endpoints were local control (LC) and progression-free survival (PFS).Median age at diagnosis was 54.5 years (range 15-74 years). Forty-seven patients were stage I (97.9%); 15 patients (31.3%) had grade 3 disease. Initial management consisted of observation (12 patients; 25.0%), radiation therapy (RT) alone (12 patients; 25.0%), systemic therapy alone (9 cases; 18.8%), or both (15 patients; 31.3%). Median follow-up was 4.92 years (range 0.5-13.83 years). 4-year PFS and OS were 80.9% and 97.1%, respectively. Patients treated with additional therapy experienced significantly better 4-year LC (100% vs. 81.8%; p = .012) and 4-year PFS (86.7% vs. 63.6%; p = .006).Patients with completely resected limited-stage FL would benefit from therapy beyond excisional biopsy alone.

Limited stage grade 3 follicular lymphoma patients can experience favorable outcomes with combined modality therapy

Controversy exists regarding the optimal management of limited stage grade 3 follicular lymphoma (FL3). We assessed the treatment outcomes of 190 consecutive patients with stage I-II FL. Fifty two patients had FL3 disease, in whom the median age was 55 years. At a median follow-up of 65 months, 5-year progression-free survival (PFS) and overall survival (OS) rates were 76.6% and 87.6%, respectively. Patients receiving systemic therapy followed by radiation therapy (RT) had a significantly better PFS (p=.003) than those treated with RT alone, but similar OS (p = .476). Patients treated with RT had 100% local control. Compared to 132 patients with grade 1-2 FL, those with FL3 had similar PFS (p = .493) and OS (p  =  .330). Patients with FL3 can experience favorable outcomes when treated with a combination of systemic therapy and RT, comparable to low grade FL.

Rituximab With Involved Field Irradiation for Early-stage Nodal Follicular Lymphoma: Results of the MIR Study

The MabThera and Involved field Radiotherapy study investigated efficacy and safety of involved field (IF) radiotherapy in combination with the anti-CD20 antibody Rituximab for early-stage follicular lymphoma (FL) in a prospective, single-arm multicenter phase 2 design. Eighty-five stage I–II FL patients received 8 cycles of Rituximab (375 mg/m²) and IF irradiation (30/40 Gy). The primary endpoint was progression-free survival (PFS) 2 years from treatment start. Secondary endpoints were overall survival (OS), complete response rates, toxicity, quality of life, and minimal residual disease (MRD) response with protocol defined visits up to month 30. For the primary endpoint, PFS at 2 years was 85% for the intention-to-treat set. Long-term data were captured in selected sites and evaluated as post hoc analysis in the per protocol (PP) set: PFS and OS were 78% and 96% at 5 years with a median follow-up of 66 or 78 months, respectively. There were 17/76 recurrences in the PP set, of which 14 were outside the radiation volume only. MRD analyses revealed a clonal marker in 36% of patients at diagnosis. All but 1 marker positive patients experienced a molecular treatment response. There were 13 serious adverse events (4 related to the therapy) during the first 30 months. IF radiotherapy combined with Rituximab is well tolerated and highly efficient with low rates of recurrence in the first years in early-stage FL. The efficacy is comparable with more aggressive therapy approaches without compromising the quality of life and maintains for an extended follow-up of more than 5 years.

Definitive radiotherapy for localized follicular lymphoma staged by 18F-FDG PET-CT: a collaborative study by ILROG

Radiotherapy (RT) can be curative in patients with localized follicular lymphoma (FL), with historical series showing a 10-year disease-free survival of 40 to 50%. As ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography with computerized tomography (PET-CT) upstages 10 to 60% of patients compared to CT, we sought to evaluate outcomes in patients staged by PET-CT, to determine if more accurate staging leads to better patient selection and results. We conducted a multicenter retrospective study under the direction of the International Lymphoma Radiation Oncology Group (ILROG). Inclusion criteria were: RT alone for untreated stage I to II FL (grade 1-3A) with dose equivalent ≥24 Gy, staged by PET-CT, age ≥18 years, and follow-up ≥3 months. End points were freedom from progression (FFP), local control, and overall survival (OS). A total of 512 patients treated between 2000 and 2017 at 16 centers were eligible for analysis; median age was 58 years (range, 20-90); 410 patients (80.1%) had stage I disease; median RT dose was 30 Gy (24-52); and median follow-up was 52 months (3.2-174.6). Five-year FFP and OS were 68.9% and 95.7%. For stage I, FFP was 74.1% vs 49.1% for stage II (P < .0001). Eight patients relapsed in-field (1.6%). Four had marginal recurrences (0.8%) resulting in local control rate of 97.6%. On multivariable analysis, stage II (hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.44-3.10) and BCL2 expression (HR, 1.62; 95% CI, 1.07-2.47) were significantly associated with less favorable FFP. Outcome after RT in PET-CT staged patients appears to be better than in earlier series, particularly in stage I disease, suggesting that the curative potential of RT for truly localized FL has been underestimated.

Cancer Immunotherapy and the Immune Response in Follicular Lymphoma

Follicular lymphoma (FL) is the most frequent indolent lymphoma in the Western world and is characterized in almost all cases by the t(14;18) translocation that results in overexpression of BCL2, an anti-apoptotic protein. The entity includes a spectrum of subentities that differ from an indolent to a very aggressive growth pattern. As a consequence, treatment can include watch & wait up to intensive chemotherapy including allogeneic stem cell transplantation. The immune cell microenvironment has been recognized as a major driver of outcome of FL patients and gene expression profiling has identified a clinically relevant gene expression signature that classifies an immune response to the lymphoma cells. It is known for some time that the immune cell composition of the lymphoma microenvironment is important because high numbers of tissue-infiltrating macrophages correlate with poor outcome in patients receiving chemotherapy but not in patients receiving the combination of chemotherapy and CD20-specific monoclonal antibody rituximab. In addition, TCR signaling of tumor-infiltrating lymphocytes is dysfunctional leading to an impaired capacity to form an intact immunologic synapse. Approaches restoring local T cell function, e.g., by usage of checkpoint inhibitors has demonstrated clinical activity (ORR 40%) and can achieve long-term remissions. Ongoing trials with re-programmed autologous CART cells achieve response rates in approximately 50% of FL patients with relapsed and even refractory disease. Responses lasting for more than 6 months might be durable, indicative for a successful restoration of a functional immune system. In summary, FL is a malignant disease where the control by the immune system ultimately decides about progression and transformation rate. The advent of monoclonal antibodies has changed the way we treat FL and new approaches restoring the individual immune control will hopefully improve results further.

Rituximab maintenance therapy of follicular lymphoma in clinical practice

Standard of care for patients with symptomatic, advanced‐stage follicular lymphoma (FL) is rituximab‐containing chemoimmunotherapy followed by rituximab maintenance. This prospective, multicenter, noninterventional study analyzed how efficacy and safety data from randomized controlled trials translate into clinical practice in Germany. Both treatment‐naïve and relapsed/refractory patients with FL, who responded to rituximab‐containing induction and were scheduled for rituximab maintenance, were observed for 24 months. Effectiveness was measured by response and Kaplan‐Meier survival analysis. In addition, treatment patterns of induction and maintenance, as well as adverse events, were documented. The evaluable study population consisted of 310 first‐line patients and 173 relapsed/refractory patients, including 116 patients with initial Ann‐Arbor stage I/II and 20 patients with FL grade 3B. Regarding first‐line induction, a shift from R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) to R‐bendamustine was observed over time, as well as a decline in radiotherapy. 2‐year progression‐free survival rates were 88.3% (95% confidence interval [CI] 84.0‐92.6) for first‐line patients and 76.0% (95% CI: 68.8‐83.3) for relapsed/refractory patients. Conversion from partial to complete remission (PR, CR) occurred in 53.4% of analyzed first‐line patients with PR, resulting in 69.4% CRs at study end (relapsed/refractory: conversion in 42.9%, final CRs 57.9%). Safety results were consistent with the known safety profile of rituximab in this setting. Both treatment‐naïve and relapsed/refractory patients with FL show favorable 2‐year PFS rates and improvements in the remission status with postinduction rituximab monotherapy as maintenance and consolidation therapy.

Treatment of localized-stage follicular lymphoma

Follicular lymphoma (FL) is the most common indolent lymphoma, and it most frequently presents in an advanced stage. Therapeutic considerations for advanced stage are different from those of localized-stage FL, in which radiotherapy (RT) is generally recommended. However, the available evidence suffers from shortcomings that are relatively specific to this clinical entity due to its rarity and long survival with all available treatment modalities, including that most of the existing evidence originated at a time when diagnostic classifications, staging procedures and radiotherapeutic standards were different from those available today and when anti-CD20 monoclonal antibodies were not available. Available treatment modalities include observation, systemic therapy only, RT only and RT in combination with systemic therapy. We review the evidence available with each of them and the data from present-day clinical practice studies as well as briefly discuss what diagnostic and therapeutic developments may take place in the next few years.

Clinical management and outcomes of completely resected stage I follicular lymphoma

Recent studies have revealed the clinical and biological features of stage I follicular lymphoma (FL), but information about patients with stage I FL who underwent total resection after tissue biopsy is limited. Among 305 FL patients diagnosed between 2001 and 2013, clinical stage I disease was observed in 36 patients. Of these, 18 patients underwent total resection after diagnostic tissue biopsy. We used ¹⁸F-fluorodeoxyglucose positron emission CT for staging assessment in 13 of 18 patients (72.2%). The median age was 56.5 years. Six patients (33.3%) were male. The soluble interleukin-2 receptor alpha concentration was significantly lower than in patients with residual disease. Among these 18 patients, 7 patients (38.9%) were treated with a "watch-and-wait" (WW) policy, 7 (38.9%) were treated with involved-field irradiation, and 4 (22.2%) received systemic chemotherapy. Patients with resected disease were treated with significantly different strategies from those with residual disease (p = 0.0026). Five patients experienced relapse during follow-up (median follow-up: 48.2 months). All relapses were distant from the primary site, irrespective of treatment strategy. Among all stage I patients, disease resection was not a significant factor for survival (p = 0.9294). Collectively, the choice of treatment strategy was significantly influenced by patient status. Resection status was not significantly associated with survival after several treatment strategies.

Radiotherapy plus rituximab as first-line regimen for localized follicular lymphoma

Early-stage follicular lymphoma (FL) can be cured with involved-field radiotherapy (IF-RT); however, many patients relapse in non-irradiated areas. A combined association with chemotherapy could increase treatment efficacy, but toxic effects could be unacceptable. In vitro synergistic effect between rituximab (R) and RT has been observed, but clinical data are limited. We retrospectively analyzed 41 early-stage FL patients receiving R and IF-RT as first-line treatment. We administered R 375mg/m² weekly for four courses, before or after IF-RT (median dose 24 Gy). Primary outcome was PFS, secondary endpoints were CR rate, OS and safety. All patients achieved CR, after a median follow-up of 46 months only three patients relapsed after 18, 26 and 42 months; estimated 5-year PFS was 90%. We suggest R in association with IF-RT could represent a feasible first-line treatment option for early-stage FL and could increase efficacy without additional toxicity compared to available data about RT alone.

Sites of extranodal involvement are prognostic in patients with stage 1 follicular lymphoma

Objectives

Follicular lymphoma (FL) is the most common indolent B cell lymphoma in the United States and a quarter of patients present with stage I disease. The objective of this study was to examine if primary site of disease influences survival in early stage lymphoma.

Results

The most common extranodal primary sites were the integumentary system (8%), followed by the GI tract (6.4%) and head & neck (5.6%). We stratified patients into a pre-rituximab era (1983-1998) and the rituximab era (1999-2011). In multivariable analysis, integumentary disease was associated with better overall survival (Hazard Ratio [HR], 0.77; Confidence Interval [CI], 0.66-0.9) while primary site FL of the nervous system (HR, 2.40; CI, 1.72-3.38) and the musculoskeletal system (HR, 2.14; CI, 1.44-3.18) were associated with worse overall survival when compared to primary nodal FL. Treatment in the pre-rituximab era, male gender and older age at diagnosis were associated with worse survival.

Methods

We queried the SEER database from 1983 to 2011. We included all adult patients (>18 years) with histologically confirmed stage I FL, active follow-up, and a single primary tumor. A total of 9,865 patients met eligibility criteria, with 2520 (25%) having an extranodal primary site. We classified the primary sites by organ or anatomic location into 11 sites.

Conclusion

Primary site of disease is a prognostic factor for patients with early stage FL and may help identify subsets of patients that could benefit from early, aggressive treatment.

[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.

Radiotherapy for Non-Hodgkin's lymphoma: still standard practice and not an outdated treatment option

Two large, recently published observational studies demonstate a clear down-trend in the use of radiotherapy (RT) over the last 15 years, both in the setting of follicular and diffuse large B-cell lymphoma. This change of practice might have a negative impact on clinical outcome. Even within the context of modern systemic therapy, omission of RT translates not only into a shorter progression-free survival (PFS), but also into a worse overall survival (OS). RT should therefore remain standard practice.

This short review is aiming to summarize current guidelines and the best evidence available in the management of non-Hodgkin’s lymphoma. Potentially practice changing, ongoing trials will be highlighted.

Disparities in Receipt of Radiotherapy and Survival by Age, Sex, and Ethnicity among Patient with Stage I Follicular Lymphoma

Background

Radiotherapy (RT) is a first-line treatment option for stage I follicular lymphoma (FL). We studied disparities in receipt of RT and survival among patients with stage I FL.

Methods

Adult patients (age ≥18 years) with stage I FL, as the first primary cancer, diagnosed between 1992 and 2007 were identified using Surveillance, Epidemiology, and End Results (SEER) 18 database. Study population was divided into various subgroups based on age, sex, race, and marital status. Factors associated with receipt of RT and survival, among patients receiving RT, was evaluated using regression analysis and Cox PH modeling, respectively. SEER*Stat was used to compute 1- and 5-year RS for various subgroups and compared using Z score.

Results

Of the total 7315 patients (median age: 64 years), 2671 (36.5%) received RT. African-Americans, older age group, and single and separated/divorced/widow marital status predicted omission of RT. The 1- and 5-year RS were significantly better in patients receiving RT. In multivariate analysis, male sex, age <60 years, Caucasian race, and married marital status were found to be independent predictor of better RS among patients receiving RT (P < 0.0001).

Conclusion

This study showed that 36.5% patients with stage I FL received RT. Survival rates were significantly better for patients who received RT.

Underutilization of radiation therapy in early-stage marginal zone lymphoma negatively impacts overall survival

PURPOSE

Multiple population-based studies have suggested increasing omission of radiation therapy in favor of alternative treatment strategies in lymphomas, with an associated negative impact on survival. Radiation therapy has long been considered the standard management for many mucosa-associated lymphoid tissue lymphomas. Thus, we aimed to evaluate patterns of treatment utilization and survival.

METHODS AND MATERIALS

A retrospective analysis based on the National Cancer Database was performed on 22,378 patients with splenic, nodal, or extranodal stage I-II marginal zone lymphoma diagnosed between 1998 and 2012. A logistic regression model was used to assess the association between sociodemographic, tumor, and treatment characteristics and the utilization of radiation therapy. Multivariate propensity score-adjusted Cox proportional hazards models were performed to identify factors independently associated with overall survival (OS).

RESULTS

Of 22,378 patients, 82% had stage I disease, 77% had extranodal mucosa-associated lymphoid tissue lymphoma, 5% had splenic marginal zone lymphoma, and 64% were older than 60 years. Radiation therapy utilization decreased from a peak of 39% in 2007 to 33% in 2011 (P < .001), with a corresponding significant increase in systemic therapy utilization. Radiation therapy was associated with a 5- and 10-year OS of 86.7% and 68.8% compared with 78.3% and 54.3% for no radiation therapy (P < .001). On multivariate propensity score-adjusted survival analysis, radiation therapy remained independently associated with improved OS (hazard of death, 0.75; 95% confidence interval, 0.65-0.85; P < .001).

CONCLUSIONS

Although clinical guidelines endorse radiation therapy as the preferred initial therapy for early-stage nongastric and Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma, radiation therapy is underused. Radiation therapy with or without systemic therapy was associated with a significant improvement in OS and should remain standard of care.

Management Trends and Outcomes for Stage I to II Mantle Cell Lymphoma Using the National Cancer Data Base: Ascertaining the Ideal Treatment Paradigm

PURPOSE

Mantle cell lymphoma (MCL) is a rare, albeit aggressive subset of non-Hodgkin lymphoma, resulting in varied treatment approaches. Given the paucity of data defining the optimal management for early-stage MCL, we conducted an analysis using the National Cancer Data Base (NCDB) to identify practice patterns and outcomes.

METHODS AND MATERIALS

The NCDB was queried for patients with stage I to II MCL diagnosed from 1998 to 2012 receiving chemotherapy (CT) or radiation therapy (RT), or both (CT+RT). Univariate and multivariable analyses for factors associated with treatment selection were completed using logistic regression. Propensity scores with inverse probability treatment weighting (IPTW) were calculated based on the conditional probability of receiving CT+RT. The log-rank test and Cox proportional hazards modeling with IPTW adjustment were conducted for the survival analyses.

RESULTS

In total, 2539 patients were identified. The key characteristics were as follows: 69% were male, 71% were aged ≥60 years, 28% had extranodal involvement, and 51% had stage I disease. Of the 2539 patients, 70% underwent CT, 11% underwent RT, and 19% underwent CT+RT. The use of CT+RT decreased from 23.1% to 14.1% in 1998 to 2002 and 2010 to 2012 (P<.001). CT+RT usage was lower for patients with the following characteristics: age ≥60 years, female sex, stage II disease, and the presence of B symptoms. With a median follow-up period of 42.8 months, the unadjusted 3-year overall survival estimates for patients receiving CT, RT, or CT+RT were 67.8%, 72.4%, and 79.8%, respectively (P<.001). After correcting for indication bias through IPTW-adjusted modeling, CT+RT reduced the risk of overall mortality compared with monotherapy (hazard ratio 0.65, P=.029).

CONCLUSIONS

Although uncommon, patients with stage I-II MCL can have favorable outcomes. Despite a continued decline in the usage of consolidative RT, combined modality therapy improves survival in this cohort compared with monotherapy.