A comparative analysis of prognostic factor models for follicular lymphoma based on a phase III trial of CHOP-rituximab versus CHOP + 131iodine--tositumomab

Progression-free survival after front line, second line and third line in patients with follicular lymphoma treated in clinical practice

BACKGROUND

The modern-day therapeutic landscape for follicular lymphoma (FL) includes a number of highly effective therapies.

PATIENTS AND METHODS

We set out to determine progression-free survival (PFS) after front line, second line, and third line of therapy on the basis of relevant biological characteristics and therapeutic choices. Patients (n = 743, 51% females, median 60 years old) diagnosed with grade 1-2 FL between 1997 and 2016 in nine institutions were included.

RESULTS

The median PFS1, PFS2, and PFS3 were 8.1 years (95% confidence interval [CI]: 7-9.3 years), 4.2 years (95% CI: 2.8-5.6 years) and 2.2 years (95% CI 1.7-2.8 years). We found longer PFS1 for (1) females, (2) younger age, (3) lower-risk follicular lymphoma international prognostic index (FLIPI), (4) standard intensity (over low intensity) regimens and (5) immunochemotherapy strategies and (6) maintenance rituximab. We found a shorter PFS2 for patients who received front-line immunochemotherapy. Older age at diagnosis correlated with a shorter PFS3. Intensity of front-line chemotherapy, maintenance, or POD24 status did not correlate with PFS2 or PFS3 in this dataset.

INTERPRETATION

With current immunochemotherapy strategies, the natural course of FL is characterized by shorter-lasting remissions after each relapse. It will be interesting to see whether new therapies can alter this pattern.

Follicular lymphoma: is there an optimal way to define risk?

Follicular lymphoma (FL) has a long natural history and typically indolent behavior. In the present era, there are a plethora of prognostic factors combining clinical, biological, and genetic data to determine patient prognosis and help develop treatment strategies over the course of a patient's lifetime. The rapid pace of tumor-specific and clinical advances in FL has created a challenge in the prioritization and implementation of these factors into clinical practice. Developing a comprehensive understanding of existing prognostic markers in FL will help select optimal ways of utilization in the clinical setting and investigate opportunities to define and intervene upon risk at FL diagnosis and disease recurrence.

Follicular Lymphoma: Refining Prognostic Models and Impact of Pod-24 in Clinical Outcomes

Follicular lymphoma (FL) is the most common indolent lymphoma, accounting for 20%-25% of all non-Hodgkin's lymphomas (NHLs). It is a malignancy with variable biologic presentation and heterogeneous clinical outcomes. Several models incorporating clinical laboratory variables and molecular biomarkers are able to predict its prognosis, allowing to stratify patients into different risk groups. However, these prognostic scores should not be used to indicate first-line treatment or risk-adapted therapeutic recommendations. Over the past 5 years, progression of disease within 24 months (POD-24) of first-line chemo-immunotherapy has emerged as a robust adverse prognostic factor, capable of assessing overall survival and identifying high-risk patients with indication for more aggressive therapeutic approaches, such as consolidation based in autologous stem cell transplantation. It should be reinforced that POD-24 is not a baseline measurement, it is based on a post-treatment strategy, and is usually applied to patients with a high tumor burden. The identification of newly diagnosed patients at high risk for disease progression, particularly those with low tumor volume is still a challenge in the context of FL. Therefore, the primary purpose of this review is to provide an overview of the main prognostic models validated to date for FL. Moreover, using these scores, which incorporate clinical and genetic variables, we aim to identify individuals with newly diagnosed FL, advanced disease, and low tumor burden with a high probability of progression or relapse within 24 months of first treatment. Thus, a decision regarding risk-adapted induction therapy could be better stablished for these subset of patients.

The clinical applicability of current prognostic models in follicular lymphoma: A systematic review

The Follicular Lymphoma International Prognostic Index (FLIPI) is widely used for risk stratification of patients with follicular lymphoma (FL). Motivated by evolvement in treatment modalities, several prognostic models for FL have been proposed recently. This systematic review aimed to identify available prognostic models for newly diagnosed FL and discuss their potential limitations. A total of ten studies fulfilled the inclusion criteria. Different clinical, laboratory, radiological, and histopathological findings were combined in prognostic models. The majority of studies developed models from clinical trial cohorts, and most lacked validation in populations treated with current treatment options. Although the FLIPI is the most widely used model for prognostication in FL patients, current prognostic models, including FLIPI, are rarely used in clinical practice for treatment decision-making. Future studies should validate the existing, or develop new prognostic models, to identify which of the current standard treatment options benefit high-risk FL patients the most.

Baseline FDG-PET/CT detects bone marrow involvement in follicular lymphoma and provides relevant prognostic information

In follicular lymphoma (FL), detection of bone marrow (BM) involvement (BMI) by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) improves the accuracy of staging vs BM biopsy (BMB) alone. Our objective was to determine the diagnostic utility of PET for BMI FL and the prognostic value of BMI by PET (positive PET result [PET+]). Records of patients (2002-2016) with PET and BMB at the time of initial treatment were reviewed. BMI was identified by positive BMB result (BMB+) and/or unifocal or multifocal BM FDG uptake on blindly reviewed PET scans with no corresponding CT abnormality (PET+). Among 261 patients, BMI was diagnosed in 78 patients (29.9%) by PET+, in 81 patients (31.0%) by BMB+, and in 113 patients (43.3%) by either PET+ or BMB+. PET+ upstaged 24 patients to stage IV, including 10 from stages I or II to stage IV. Median duration of follow-up was 6.0 years (range, 0-16.6 years). In univariate analysis, a high Follicular Lymphoma International Prognosis Index (FLIPI) score, PET+, and BMB+ correlated with shorter progression-free survival (PFS; all P ≤ .03), and high FLIPI, PET+, and combined PET+ and BMB+ with shorter overall survival (OS; all P ≤ .01). In multivariate analysis, PET+ was the only independent predictor of PFS, whereas high FLIPI score and PET+ predicted OS (P ≤ .03). Combined PET and BMB identify BMI more accurately than either BMB or PET alone, but BMB rarely adds critical information. For patients initiating treatment of FL, identification of BMI by PET is predictive of PFS and OS.

Phase 2 Study of Iodine-131 Tositumomab Plus Chemotherapy in Patients With Previously Untreated Mantle-Cell Lymphoma

BACKGROUND

Mantle-cell lymphoma (MCL) is sensitive to radiotherapy, and the CD20 antigen is relatively highly expressed in MCL. Therefore, radioimmunotherapy using radiolabeled anti-CD20 monoclonal antibodies has the potential to treat MCL. The objective of this study was to investigate the efficacy, pharmacokinetics, and safety of tositumomab (TST) and iodine-131 tositumomab (I-131 TST) followed by 6 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with previously untreated MCL (ClinicalTrials.govNCT00022945).

PATIENTS AND METHODS

In this phase 2 open-label study, patients received dosimetric (day 0: 450 mg TST, then 35 mg I-131 TST [5 mCi]) and therapeutic (between days 7 and 14: 450 mg TST, then an individualized dose of I-131 TST [65-75 cGy]) TST/I-131 TST, with CHOP treatment commencing approximately 13 weeks after the therapeutic dose. The primary end point was the MCL response rate to treatment; secondary end points included confirmed complete response rate and total body residence time.

RESULTS

Twenty-six patients were enrolled, and 25 were included in the intent-to-treat population. The overall unconfirmed response rate was 84%, and the confirmed complete response rate was 44%. The median progression free-survival was 27.6 months. The median total body residence time was 94.5 hours. No new or unexpected safety signals were identified.

CONCLUSION

Patients with previously untreated MCL who received radioimmunotherapy with TST/I-131 TST followed by CHOP had a high response rate and a long duration of response, indicating that radioimmunotherapy is a therapeutic option in this patient population.

Long-term survival and prognostic analysis of advanced stage follicular lymphoma in the rituximab era: A China single-center retrospective study

AIM

The prognosis and treatment options for follicular lymphoma (FL) remain heterogenous. This study aimed to analyze the prognostic impact of rituximab maintenance and evaluate the prognostic models in Chinese FL patients.

METHODS

We retrospectively evaluated patients with treatment-naïve advanced stage FL who were treated in Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College between January 2008 and December 2018. We compared the baseline characteristics, long-term survival outcomes, prognostic factors and the performance of four common prognostic models (i.e., FLIPI, FLIPI2, PRIMA-PI and LDH+β2M) between them.

RESULTS

A total of 158 patients were included (rituximab maintenance group, 77 patients; observation group, 81 patients). The median follow-up time was 61.0 months. The rituximab maintenance group showed significantly higher 5-year progression-free survival (PFS; 83.3% vs 52.7%, P < 0.001) and overall survival (OS; 97.8% vs 84.1%, P = 0.032) than the observation group. FLIPI2 showed a more discriminating C index than the other three models.

CONCLUSION

This study showed that rituximab maintenance after chemoimmunotherapy induction can prolong both PFS and OS in patients with advanced-stage FL, and FLIPI2 is a promising prognostic model.

Precision medicine in follicular lymphoma: Focus on predictive biomarkers

Current care for patients with follicular lymphoma (FL) offers most of them long-term survival. Improving it further will require careful patient selection. This review focuses on predictive biomarkers (ie, those whose outcome correlations depend on the treatment strategy) in FL, because awareness of what patient subsets benefit most or least from each therapy will help in this task. The first part of this review aims to summarize what biomarkers are predictive in FL, the magnitude of the effect and the quality of the evidence. We find predictive biomarkers in the setting of (a) indication of active treatment, (b) front-line induction (use of anthracyline-based regimens, CHOP vs bendamustine, addition of rituximab), (c) post-(front-line)induction (rituximab maintenance, radioimmunotherapy), and (d) relapse (hematopoietic stem cell transplant) and targeted agents. The second part of this review discusses the challenges of precision medicine in FL, including (a) cost, (b) clinical relevance considerations, and (c) difficulties over the broad implementation of biomarkers. We then provide our view on what biomarkers may become used in the next few years. We conclude by underscoring the importance of assessing the potential predictiveness of available biomarkers to improve patient care but also that there is a long road ahead before reaching their broad implementation due to remaining scientific, technological, and economic hurdles.

Absolute B cell counts in blood predict long-term response in follicular lymphoma patients treated with rituximab without chemotherapy

Rituximab monotherapy is widely used for follicular lymphoma. However, there are no established predictors for response or response duration. We analyzed the long-term prognostic relevance of pre-treatment absolute blood counts of lymphocytes with subsets and monocytes in 265 follicular lymphoma patients, uniformly treated with rituximab without chemotherapy, in two Nordic Lymphoma Group trials. There were 265 previously untreated, stage II–IV follicular lymphoma patients with a median follow-up of over 10 years. Absolute B cell counts ≥ median (0.09 × 10⁹/L) were an independent predictor for shorter time to next treatment or death (multivariable analysis P = 0.010). In univariate analysis, absolute monocyte counts ≥ median (0.5 × 10⁹/L) did not correlate with time to next treatment or death, but with inferior overall survival (P = 0.034). Absolute T cell or T cell subset counts were not predictive for outcome. High absolute B cell counts, possibly reflecting circulating lymphoma cells, have an unfavorable impact on time to next treatment or death in patients treated with rituximab without chemotherapy.

Molecular and clinical progress in follicular lymphoma lacking the t(14;18) translocation (Review)

Although the majority of patients with follicular lymphoma (FL) harbor the t(14;18)(q32;q21) IGH/BCL2 gene rearrangement that leads to the overexpression of BCL2 protein, approximately 20% of FL cases lack t(14;18)(q32;q21). It is considered that BCL2 overexpression underscores the development of the majority of cases of FL and their transformation to more aggressive lymphoma [known as transformed FL (tFL)]. However, FL cases lacking the t(14;18)(q32;q21) translocation exhibit symptoms analogous to their t(14;18)‑positive counterparts. An important goal of recent research on FL has been to clarify the distinctions between the two different forms of FL. Numerous studies have shed light onto the genetic and molecular features of t(14;18)‑negative FL and the related clinical manifestations. In this review, we summarize the current knowledge of t(14;18)‑negative FL occurring in the lymph nodes with an emphasis on the underlying molecular and clinical features. In addition, novel treatment directions are discussed.

The α-emitter astatine-211 targeted to CD38 can eradicate multiple myeloma in a disseminated disease model

Minimal residual disease (MRD) has become an increasingly prevalent and important entity in multiple myeloma (MM). Despite deepening responses to frontline therapy, roughly 75% of MM patients never become MRD-negative to ≤10-5, which is concerning because MRD-negative status predicts significantly longer survival. MM is highly heterogeneous, and MRD persistence may reflect survival of isolated single cells and small clusters of treatment-resistant subclones. Virtually all MM clones are exquisitely sensitive to radiation, and the α-emitter astatine-211 (211At) deposits prodigious energy within 3 cell diameters, which is ideal for eliminating MRD if effectively targeted. CD38 is a proven MM target, and we conjugated 211At to an anti-CD38 monoclonal antibody to create an 211At-CD38 therapy. When examined in a bulky xenograft model of MM, single-dose 211At-CD38 at 15 to 45 µCi at least doubled median survival of mice relative to untreated controls (P < .003), but no mice achieved complete remission and all died within 75 days. In contrast, in a disseminated disease model designed to reflect low-burden MRD, 3 studies demonstrated that single-dose 211At-CD38 at 24 to 45 µCi produced sustained remission and long-term survival (>150 days) for 50% to 80% of mice, where all untreated mice died in 20 to 55 days (P < .0001). Treatment toxicities were transient and minimal. These data suggest that 211At-CD38 offers the potential to eliminate residual MM cell clones in low-disease-burden settings, including MRD. We are optimistic that, in a planned clinical trial, addition of 211At-CD38 to an autologous stem cell transplant (ASCT) conditioning regimen may improve ASCT outcomes for MM patients.

Yttrium-90 ibritumomab tiuxetan consolidation versus rituximab maintenance therapy after induction chemotherapy in patients with indolent non-Hodgkin lymphoma: a single-institution experience

OBJECTIVES

Indolent B-cell non-Hodgkin lymphomas (iNHLs) are considered incurable. Rituximab maintenance and yttrium-90 ibritumomab tiuxetan (⁹⁰Y-IT) consolidation are promising post-remission therapies. However, only one randomized phase II trial has compared their efficacies and adverse effects. Here, we compared the efficacy and safety of ⁹⁰Y-IT consolidation and rituximab maintenance in iNHL patients.

METHODS

We retrospectively examined 75 iNHL patients with complete or partial response after initial chemotherapy between January 2008 and December 2018. Twenty-seven patients received ⁹⁰Y-IT consolidation and 48 received rituximab maintenance (every 2 months for 2 years). Progression-free survival (PFS), overall survival (OS), and time to next treatment (TTNT) were estimated from the start of the treatment, and adverse effects were evaluated.

RESULTS

After a median 3.6-year follow-up, the 5-year PFSs of the ⁹⁰Y-IT consolidation and rituximab maintenance groups were 75.5% and 82.4%, respectively (log-rank test, p = 0.839), and the 5-year OSs were 100% and 97.8%, respectively (log-rank test, p = 0.465). The corresponding median TTNTs were not reached (log-rank test, p = 0.804). The commonest adverse effect with ⁹⁰Y-IT consolidation was hematotoxicity; lower rates and grades of cytopenia were observed in patients who received rituximab maintenance. Secondary malignancies were observed in 1 patient (4%) who received ⁹⁰Y-IT consolidation and 2 patients (4.2%) who received rituximab maintenance (Fisher's exact test, p > 0.99).

CONCLUSION

⁹⁰Y-IT consolidation and rituximab maintenance were similar with respect to PFS, OS, and TTNT. However, the features and grades of adverse effects significantly differed. Patient-specific characteristics should be considered when deciding post-remission treatments.

Detection of extranodal and spleen involvement by FDG-PET imaging predicts adverse survival in untreated follicular lymphoma

Predicting early clinical failure in patients with untreated follicular lymphoma (FL) is important but difficult. This study aimed to determine the incidence and patterns of extranodal (EN) and spleen disease using PET/CT, and assess their utility in predicting early clinical failure. PET/CT images from 613 cases of untreated FL (2003-2016) were reviewed. The location and number of EN sites, patterns of bone involvement, and splenic involvement were recorded. Outcomes were assessed using event-free survival (EFS), overall survival (OS), and early clinical failure at 24 months (EFS24). So, 49% (301/613) of patients had PET/CT-detected EN involvement, and 28% (171/613) had spleen involvement. The presence of ≥2 EN sites, spleen, bone or soft tissue involvement all predicted failure to achieve EFS24. Presence of ≥2 EN sites and bone involvement pattern were also predictive of OS in a univariate analysis. In a multivariate analysis with FLIPI-2 factors, spleen involvement, pattern of bone involvement, and soft tissue involvement independently predicted a lower EFS (HR 1.49 (1.11-2.00), P = .007; HR 1.71 (1.10-2.65), P = .017; and HR 1.67 (1.06-2.62), P = .026, respectively). When the multivariate analysis was performed using PRIMA-PI factors (marrow and B2M), the number of EN sites was an independent prognostic factor for inferior OS (HR 2.28; P = .05). Baseline PET/CT identifies EN involvement in nearly half of patients with untreated FL. The presence of ≥2 EN sites, bone, soft tissue, or splenic involvement predicts early clinical failure. These results, when combined with other factors, may better identify high-risk patients and guide therapy.

Novel treatment approaches and future perspectives in follicular lymphoma

Follicular lymphoma (FL) is a common B-cell malignancy characterized by relatively indolent growth and incurability with an expected lifetime course of serial intermittent treatment courses. Many patients with FL have lives shortened by the disease and despite a relatively favorable prognosis relative to other incurable systemic malignancies, optimal management of FL has not been achieved. This review focuses on identifying both patients for whom novel therapies might be most beneficial as well as systematically reviewing novel strategies at various levels of investigation. Prognostic markers incorporating clinical measurements and tumor genetics are discussed, yet at the time of diagnosis do not yet powerfully discriminate patients for whom specific strategies are beneficial. Reassessment of prognosis after evaluating the response to initial therapy is the most powerful identifier of those in need of novel management strategies. For initial therapy of high burden systemic disease, anti-CD20 antibody along with chemotherapy or immunomodulators all offer relatively similar effects on overall survival with subtly different effects on progression-free survival and quality of life. Several new agents currently under investigation in the upfront setting are discussed. Perhaps the best testing ground for novel therapies is in patients with early relapse following initial immunochemotherapy. Ongoing research in multiple therapy classes including, novel monoclonal antibodies, antibody drug conjugates, immunomodulatory agents, intracellular pathway inhibitors, immune checkpoint inhibitors, and epigenetic regulators are discussed herein.

Assessing the Effectiveness of Treatment Sequences for Older Patients With High-risk Follicular Lymphoma With a Multistate Model

BACKGROUND

Disease progression within < 2 years of initial chemoimmunotherapy and patient age > 60 years have been associated with poor overall survival (OS) in follicular lymphoma (FL). No standard treatment exists for these high-risk patients, and the effectiveness of sequential therapies remains unclear.

PATIENTS AND METHODS

We studied the course of FL with first-, second-, and third-line treatment. Using large population-based data, we identified 5234 patients with FL diagnosed in 2000 to 2009. Of these patients, 71% had received second-line therapy < 2 years, and 29% had received no therapy after first-line therapy, with a median OS of < 3 years. Treatment included rituximab, R-CVP (rituximab, cyclophosphamide, vincristine), R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine), R-Other (other rituximab-containing), and other regimens. The Aalen-Johansen estimator and Cox proportional hazards models were used to quantify the outcomes and assess the effects of the clinical and sociodemographic factors.

RESULTS

R-CHOP demonstrated the most favorable 5-year OS among first- (71%), second- (55%), and third-line (61%) therapies. First-line R-CHOP improved OS (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.50-0.64) and reduced the mortality risks after first-line (HR, 0.60; 95% CI, 0.47-0.77), second-line (HR, 0.40; 95% CI, 0.29-0.53), and third-line (HR, 0.63; 95% CI, 0.53-0.76) treatments. B-symptoms, being married, and histologic grade 1/2 were associated with the use of earlier second-line therapy. Early progression from second- to third-line therapy was associated with poor OS. The repeated use of R-CHOP or R-CVP as first- and second-line treatment yielded high 2-year mortality rates (R-CHOP + R-CHOP, 17.3%; R-CVP + R-CVP, 21.1%).

CONCLUSION

Our multistate approach assessed the effect of sequential therapy on the immediate and subsequent treatment-line outcomes. We found that R-CHOP in any line improved OS for patients with high-risk FL.

Genomic alterations important for the prognosis in patients with follicular lymphoma treated in SWOG study S0016

Although recent advances in molecular genetics have enabled improved risk classification of follicular lymphoma (FL) using, for example, the m7-FLIPI score, the impact on treatment has been limited. We aimed to assess the prognostic significance of copy-number aberrations (CNAs) and copy-neutral loss of heterozygosity (cnLOH) identified by chromosome genomic-array testing (CGAT) at FL diagnosis using prospectively collected clinical trial specimens from 255 patients enrolled in the SWOG study S0016. The impact of genomic aberrations was assessed for early progression (progressed or died within 2 years after registration), progression-free survival (PFS), and overall survival (OS). We showed that increased genomic complexity (ie, the total number of aberration calls) was associated with poor outcome in FL. Certain chromosome arms were critical for clinical outcome. Prognostic CNAs/cnLOH were identified: whereas early progression was correlated with 2p gain (P = .007; odds ratio [OR] = 2.55 [1.29, 5.03]) and 2p cnLOH (P = .005; OR = 10.9 [2.08, 57.2]), 2p gain specifically encompassing VRK2 and FANCL predicted PFS (P = .01; hazard ratio = 1.80 [1.14, 2.68]) as well as OS (P = .005; 2.40 [1.30, 4.40]); CDKN2A/B (9p) deletion correlated with worse PFS (P = .004, 3.50 [1.51, 8.28]); whereas CREBBP (16p) (P < .001; 6.70 [2.52, 17.58]) and TP53 (17p) (P < .001; 3.90 [1.85, 8.31]) deletion predicted worse OS. An independent cohort from the m7-FLIPI study was explored, and the prognostic significance of aberration count, and TP53 and CDKN2A/B deletion were further validated. In conclusion, assessing genomic aberrations at FL diagnosis with CGAT improves risk stratification independent of known clinical parameters, and provides a framework for development of future rational targeted therapies.

Sequencing of therapies in relapsed follicular lymphoma

Follicular lymphoma (FL) is an incurable but treatable disease with vast treatment options. Despite the abundance of efficacious treatment modalities, there is no universally agreed upon standard approach to treatment, particularly in the relapsed/refractory setting. There is an increasing need for more robust and clinically available tools to risk-stratify patients and identify those likely to experience early relapse, which is currently recognized as the unmet need in FL. Additionally, the use of gene-expression profiling and next-generation sequencing techniques in recent years has led to a wealth of knowledge regarding the molecular drivers of lymphomagenesis. However, much of this knowledge is not currently available in the clinic to inform treatment decisions. Future studies are needed to generate clinically relevant predictive models adept at incorporating patient-specific and molecular features to inform management strategies along the entire disease continuum as treatment decisions should not be made in a vacuum with a one-size-fits-all approach. Sequencing of therapy in the management of relapsed FL should involve personalized decision-making for care plans that balance patient characteristics, preferences, and comorbidities with treatment-related factors such as efficacy, toxicity profile, and mechanisms of action to achieve a durable, quality remission.

Radioimmunotherapy as the first line of treatment in non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy. The estimated deaths and new cases of NHL in the USA in 2018 have reached 19,910 and 74,680, respectively, with 5-year survival rate of 71%. Therapeutic interventions for NHL consist of chemotherapy, radiation therapy and immunotherapy. Radioimmunotherapy (RIT) is a potential alternative treatment for NHL that is currently used in different lines of treatment. Studies show that nuclear medicine physicians and radiation oncologists are not yet certain about the proper line for administration of RIT. Herein, we have reviewed the efficiency and toxicity of RIT as the first line of treatment, and discussed potential novel indications, and strategies such as modifying induction therapy and using rituximab maintenance to optimize the efficiency of RIT as the first line of treatment. Our review indicates that it is more logical to postpone conventional therapies to the second or third lines of treatment instead of RIT.

Unmet needs in the first-line treatment of follicular lymphoma

For the majority of patients with newly diagnosed follicular lymphoma (FL), current treatments, while not curative, allow for long remission durations. However, several important needs remain unaddressed. Studies have consistently shown that ∼20% of patients with FL experience disease progression within 2 years of first-line treatment, and consequently have a 50% risk of death in 5 years. Better characterization of this group of patients at diagnosis may provide insight into those in need of alternate or intensive therapies, facilitate a precision approach to inform clinical trials, and allow for improved patient counseling. Prognostic methods to date have employed clinical parameters, genomic methods, and a wide assortment of biological and biochemical markers, but none so far has been able to adequately identify this high-risk population. Advances in the first-line treatment of FL with chemoimmunotherapy have led to a median progression-free survival (PFS) of approximately 7 years; creating a challenge in the development of clinical trials where PFS is a primary end point. A surrogate end point that accurately predicts PFS would allow for new treatments to reach patients with FL sooner, or lessen toxicity, time, and expense to those patients requiring little to no therapy. Quality of response to treatment may predict PFS and overall survival in FL; as such complete response rates, either alone or in conjunction with PET imaging or minimal residual disease negativity, are being studied as surrogates, with complete response at 30 months after induction providing the strongest surrogacy evidence to date. A better understanding of how to optimize quality of life in the context of this chronic illness is another important focus deserving of further study. Ongoing efforts to address these important unmet needs are herein discussed.

A simplified scoring system in de novo follicular lymphoma treated initially with immunochemotherapy

In follicular lymphoma (FL), no prognostic index has been built based solely on a cohort of patients treated with initial immunochemotherapy. There is currently a need to define parsimonious clinical models for trial stratification and to add on biomolecular factors. Here, we confirmed the validity of both the follicular lymphoma international prognostic index (FLIPI) and the FLIPI2 in the large prospective PRIMA trial cohort of 1135 patients treated with initial R-chemotherapy ± R maintenance. Furthermore, we developed a new prognostic tool comprising only 2 simple parameters (bone marrow involvement and β₂-microglobulin [β₂m]) to predict progression-free survival (PFS). The final simplified score, called the PRIMA-PI (PRIMA-prognostic index), comprised 3 risk categories: high (β₂m > 3 mg/L), low (β₂m ≤ 3 mg/L without bone marrow involvement), and intermediate (β₂m ≤ 3 mg/L with bone marrow involvement). Five-year PFS rates were 69%, 55%, and 37% in the low-, intermediate-, and high-risk groups, respectively (P < .0001). In addition, achieving event-free survival (EFS) or not at 24 months (EFS24) was a strong posttreatment prognostic parameter for subsequent overall survival, and the PRIMA-PI was correlated with EFS24. The results were confirmed in a pooled external validation cohort of 479 patients from the FL2000 LYSA trial and the University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellence Molecular Epidemiology Resource. Five-year EFS in the validation cohort was 77%, 57%, and 44% in the PRIMA-PI low-, intermediate-, and high-risk groups, respectively (P < .0001). The PRIMA-PI is a novel and easy-to-compute prognostic index for patients initially treated with immunochemotherapy. This could serve as a basis for building more sophisticated and integrated biomolecular scores.

Whither Radioimmunotherapy: To Be or Not To Be?

Therapy of cancer with radiolabeled monoclonal antibodies has produced impressive results in preclinical experiments and in clinical trials conducted in radiosensitive malignancies, particularly B-cell lymphomas. Two "first-generation," directly radiolabeled anti-CD20 antibodies, ¹³¹iodine-tositumomab and ⁹⁰yttrium-ibritumomab tiuxetan, were FDA-approved more than a decade ago but have been little utilized because of a variety of medical, financial, and logistic obstacles. Newer technologies employing multistep "pretargeting" methods, particularly those utilizing bispecific antibodies, have greatly enhanced the therapeutic efficacy of radioimmunotherapy and diminished its toxicities. The dramatically improved therapeutic index of bispecific antibody pretargeting appears to be sufficiently compelling to justify human clinical trials and reinvigorate enthusiasm for radioimmunotherapy in the treatment of malignancies, particularly lymphomas. Cancer Res; 77(9); 2191-6. ©2017 AACR.

Recommendations for Clinical Trial Development in Follicular Lymphoma

Follicular lymphoma (FL) is the second most common lymphoid malignancy, representing 20% to 25% of all cases of non-Hodgkin's lymphoma (NHL), and the most common of the indolent NHLs. FL is considered incurable in the majority of patients with the current standard therapeutic approaches, although outcomes have improved in the last few decades with our current therapies, with a median overall survival that now exceeds 18 years. While the majority of patients with FL have improved outcomes with our current therapeutic approaches, there are patients with high-risk disease features that have inferior outcomes to these therapies. There is an urgent need to integrate novel therapeutic agents into the treatment regimens for these patients to improve outcomes with continued evaluation of biomarkers indicative of prognosis and effects of these regimens on quality of life.

A pioneer experience in Malaysia on In-house Radio-labelling of (131)I-rituximab in the treatment of Non-Hodgkin's Lymphoma and a case report of high dose (131)I-rituximab-BEAM conditioning autologous transplant

Radioimmunotherapy is an established treatment modality in Non-Hodgkin's lymphoma. The only two commercially available radioimmunotherapies - (90)Y-ibritumomab tiuxetan is expensive and (131)I-tositumomab has been discontinued from commercial production. In resource limited environment, self-labelling (131)I-rituximab might be the only viable practical option. We reported our pioneer experience in Malaysia on self-labelling (131)I-rituximab, substituting autologous haematopoietic stem cell transplantation (HSCT) and a patient, the first reported case, received high dose (131)I-rituximab (6000MBq/163mCi) combined with BEAM conditioning for autologous HSCT.

Beta-2 microglobulin as a significant prognostic factor and a new risk model for patients with diffuse large B-cell lymphoma

Previous reports have evaluated the prognostic value of serum beta-2 microglobulin (B2MG) level in patients with non-Hodgkin lymphoma. However, its role in predicting clinical outcome of patients with diffuse large B-cell lymphoma (DLBCL) in the rituximab era has not been extensively investigated. Here, we evaluated the prognostic value of B2MG and proposed a new prognostic model including B2MG for patients with DLBCL. A total of 274 patients with newly diagnosed de novo DLBCL were retrospectively analyzed. We defined the best cutoff value as 3.2 mg/L by using a receiver operating characteristic curve. Patients with a B2MG level ≥3.2 mg/L had significantly lower overall survival (OS) and progression-free survival than those with a B2MG level <3.2 mg/L (3-year OS, 50.9% vs. 89.4%, p < 0.001; 3-year progression-free survival, 45.3% vs. 79.7%, p < 0.001). Multivariate analysis showed that B2MG, age, performance status, and Ann Arbor stage were independent prognostic factors for OS. We developed a new prognostic model consisting of these four significant factors. We stratified patients into four-risk groups: low (L, 0 factor), low-intermediate (LI, 1-2 factors), high-intermediate (HI, 3 factors), high (H, 4 factors). This new prognostic model showed better risk discrimination compared with the National Comprehensive Cancer Network-International Prognostic Index (5-year OS: 100% and 23.4% vs. 100% and 27.1%, in L and H risk groups, respectively). Our study suggested that B2MG level is a significant prognostic factor in patients with DLBCL. A new prognostic index composed of age, performance status, stage, and B2MG could stratify the outcomes of patients with DLBCL effectively and appears to be a valuable risk model for these patients. Copyright © 2016 John Wiley & Sons, Ltd.

Targeted Radionuclide Therapy of Human Tumors

Targeted radionuclide therapy is one of the most intensively developing directions of nuclear medicine. Unlike conventional external beam therapy, the targeted radionuclide therapy causes less collateral damage to normal tissues and allows targeted drug delivery to a clinically diagnosed neoplastic malformations, as well as metastasized cells and cellular clusters, thus providing systemic therapy of cancer. The methods of targeted radionuclide therapy are based on the use of molecular carriers of radionuclides with high affinity to antigens on the surface of tumor cells. The potential of targeted radionuclide therapy has markedly grown nowadays due to the expanded knowledge base in cancer biology, bioengineering, and radiochemistry. In this review, progress in the radionuclide therapy of hematological malignancies and approaches for treatment of solid tumors is addressed.

Lymphoma incidence, survival and prevalence 2004-2014: sub-type analyses from the UK's Haematological Malignancy Research Network

BACKGROUND

Population-based information about cancer occurrence and survival are required to inform clinical practice and research; but for most lymphomas data are lacking.

METHODS

Set within a socio-demographically representative UK population of nearly 4 million, lymphoma data (N=5796) are from an established patient cohort.

RESULTS

Incidence, survival (overall and relative) and prevalence estimates for >20 subtypes are presented. With few exceptions, males tended to be diagnosed at younger ages and have significantly (P<0.05) higher incidence rates. Differences were greatest at younger ages: the <15 year male/female rate ratio for all subtypes combined being 2.2 (95% CI 1.3-3.4). These gender differences impacted on prevalence; most subtype estimates being significantly (P<0.05) higher in males than females. Outcome varied widely by subtype; survival of patients with nodular lymphocyte predominant Hodgkin lymphoma approached that of the general population, whereas less than a third of those with other B-cell (e.g., mantle cell) or T-cell (e.g., peripheral-T) lymphomas survived for ≥5 years. No males/female survival differences were detected.

CONCLUSIONS

Major strengths of our study include completeness of ascertainment, world-class diagnostics and generalisability. The marked variations demonstrated confirm the requirement for 'real-world' data to inform aetiological hypotheses, health-care planning and the future monitoring of therapeutic changes.

Low Serum Vitamin D Levels Are Associated With Inferior Survival in Follicular Lymphoma: A Prospective Evaluation in SWOG and LYSA Studies

PURPOSE

Recent literature reports a potential association between high vitamin D and improved lymphoma prognosis. We evaluated the impact of pretreatment vitamin D on follicular lymphoma (FL) outcome.

PATIENTS AND METHODS

SWOG participants were previously untreated patients with FL enrolled onto SWOG clinical trials (S9800, S9911, or S0016) involving CHOP chemotherapy plus an anti-CD20 antibody (rituximab or iodine-131 tositumomab) between 1998 and 2008. Participants included in our second independent cohort were also previously untreated patients with FL enrolled onto the Lymphoma Study Association (LYSA) PRIMA trial of rituximab plus chemotherapy (randomly assigned to rituximab maintenance v observation) between 2004 and 2007. Using the gold-standard liquid chromatography-tandem mass spectrometry method, 25-hydroxyvitamin D was measured in stored baseline serum samples. The primary end point was progression-free survival (PFS).

RESULTS

After a median follow-up of 5.4 years, the adjusted PFS and overall survival hazard ratios for the SWOG cohort were 1.97 (95% CI, 1.10 to 3.53) and 4.16 (95% CI, 1.66 to 10.44), respectively, for those who were vitamin D deficient (< 20 ng/mL; 15% of cohort). After a median follow-up of 6.6 years, the adjusted PFS and overall survival hazard ratios for the LYSA cohort were 1.50 (95% CI, 0.93 to 2.42) and 1.92 (95% CI, 0.72 to 5.13), respectively, for those who were vitamin D deficient (< 10 ng/mL; 25% of cohort).

CONCLUSION

Although statistical significance was not reached in the LYSA cohort, the consistent estimates of association between low vitamin D levels and FL outcomes in two independent cohorts suggests that serum vitamin D might be the first potentially modifiable factor to be associated with FL survival. Further investigation is needed to determine the effects of vitamin D supplementation in this clinical setting.

Serum beta-2 microglobulin in malignant lymphomas: an old but powerful prognostic factor

Beta-2 microglobulin is synthesized in all nucleated cells and forms the light chain subunit of the major histocompatibility complex class I antigen. Despite its potential role as a convenient and non-invasive prognostic indicator in malignant lymphomas, the influence of serum β2 microglobulin is currently underestimated, and therapeutic decision making is rarely affected by this marker. Recent studies that included relatively large numbers of patients with specific histologic subtypes showed that serum β2 microglobulin is a potent prognostic marker in malignant lymphomas. In follicular lymphoma, this effort led to the incorporation of serum β2 microglobulin as an indicator in a new prognostic model. In this review, we summarize the current evidence supporting the role of serum β2 microglobulin as a prognostic factor in patients with malignant lymphoma and discuss perspectives for future investigations.