The CNS Relapse in T-Cell Lymphoma Index Predicts CNS Relapse in Patients with T- and NK-Cell Lymphomas.

Little is known about risk factors for central nervous system (CNS) relapse in mature T- and NK-cell neoplasms (MTNKN). We aimed to describe the clinical epidemiology of CNS relapse in patients with MTNKN and developed the CNS relapse In T-cell lymphoma Index (CITI) to predict patients at highest risk of CNS relapse. We reviewed data from 135 patients with MTNKN and CNS relapse from 19 North American institutions. After exclusion of leukemic and most cutaneous forms of MTNKN, patients were pooled with non-CNS relapse control patients from a single institution to create a CNS relapse-enriched training set. Using a complete case analysis (N=182), of whom 91 had CNS relapse, we applied a LASSO Cox regression model to select weighted clinicopathologic variables for the CITI score, which we validated in an external cohort from the Swedish Lymphoma Registry (N=566). CNS relapse was most frequently observed in patients with PTCL, NOS (25%). Median time to CNS relapse and median overall survival after CNS relapse was 8.0 months and 4.7 months, respectively. We calculated unique CITI risk scores for individual training set patients and stratified them into risk terciles. Validation set patients with low-risk (N=158) and high-risk (N=188) CITI scores had a 10-year cumulative risk of CNS relapse of 2.2% and 13.4%, respectively (HR 5.24, 95%CI 1.50-18.26, P=0.018). We developed an open-access web-based CITI calculator (https://redcap.link/citicalc) to provide an easy tool for clinical practice. The CITI score is a validated model to predict patients with MTNKN at highest risk of developing CNS relapse.

Current and upcoming treatment approaches to common subtypes of PTCL (PTCL NOS, ALCL, TFHs).

Treatment of the common nodal peripheral T-cell lymphomas (PTCLs), which include PTCL, not otherwise specified (PTCL, NOS), anaplastic large cell lymphomas, and T-follicular helper lymphomas, is evolving. These entities are currently treated similarly with CHOP or CHOEP for CD30-negative diseases or brentuximab vedotin plus CHP for CD30-positive diseases, followed by consolidation with autologous stem cell transplant in first remission. Ongoing improvements in PTCL classification, identification of predictive biomarkers, and development of new targeted agents will lead to more specific therapies that address the unique biologic and clinical properties of each entity. For example, widespread efforts focused on molecular profiling of PTCL, NOS is likely to identify distinct subtypes that warrant different treatment approaches. New agents, such as EZH1/2 and JAK/STAT pathway inhibitors, are broadening treatment options for relapsed or refractory disease. Furthermore, promising strategies optimizing immune therapy for PTCL are currently under investigation and have potential to significantly alter the therapeutic landscape. Ongoing front-line study designs incorporate understanding of disease biology and drug sensitivities and are poised to evaluate whether newer targeted agents should be incorporated into the front-line settings for the various disease entities. Although current treatment strategies lump most disease entities together, future treatment will include distinct strategies for each disease subtype that optimizes therapy for individuals. This movement towards individualized therapy will ultimately lead to dramatic improvements in prognosis for patients with PTCL.

Few and far between: clinical management of rare extranodal subtypes of mature T-cell and NK-cell lymphomas.

While all peripheral T-cell lymphomas are uncommon, certain subtypes are truly rare, with less than a few hundred cases per year in the USA. There are often no dedicated clinical trials in these rare subtypes, and data are generally limited to case reports and retrospective case series. Therefore, clinical management is often based on this limited literature and extrapolation of data from the more common, nodal T-cell lymphomas in conjunction with personal experience. Nevertheless, thanks to tremendous pre-clinical efforts to understand these rare diseases, an increasing appreciation of the biological changes that underlie these entities is forming. In this review, we attempt to summarize the relevant literature regarding the initial management of certain rare subtypes, specifically subcutaneous panniculitis-like T-cell lymphoma, hepatosplenic T-cell lymphoma, intestinal T-cell lymphomas, and extranodal NK/T-cell lymphoma. While unequivocally established approaches in these diseases do not exist, we make cautious efforts to provide our approaches to clinical management when possible.

Advances in the treatment of mycoses fungoides and Sézary syndrome: a narrative update in skin-directed therapies and immune-based treatments.

Mycoses fungoides (MF) and Sézary syndrome (SS) are cutaneous T-cell lymphomas that are often challenging to manage given the absence of reliably curative therapies, at times high symptom burden with significant detriment to quality of life, and need for ongoing treatment for disease and symptom control. Recent developments in skin-directed treatments include optimizing the use of existing topical therapies, the introduction of known dermatological agents and treatment modalities for the specific treatment of MF/SS (such as mechlorethamine gel, calcineurin inhibitor creams, and photodynamic therapy), and novel local and topical agents. For advanced disease, dedicated clinical trials have translated to exciting progress, leading to the approval of brentuximab vedotin (2017) and mogamulizumab (2018) for relapsed MF/SS. Additional studies of other active systemic agents, including various cellular therapies, represent further attempts to add to the therapeutic armamentarium in treating MF/SS. In this review, we highlight these recent advancements, ranging from optimization of skin-directed therapies to the introduction of novel systemic agents. We focus on therapies approved in the preceding five years or under investigation in advanced-phase clinical trials.

Treatment of Adult T-Cell Leukemia/Lymphoma: Established Paradigms and Emerging Directions.

OPINION STATEMENT: Adult T-cell leukemia/lymphoma (ATL) is a rare, aggressive subtype of peripheral T-cell lymphoma developing after many years of chronic, asymptomatic infection with the retrovirus human T-cell lymphotropic virus type 1 (HTLV-1). HTLV-1 is endemic to certain geographic areas of the world, and primary infection generally occurs in infancy through mother-to-child transmission via breastfeeding. In less than 5% of infected individuals, a decades-long pathogenic process culminates in the development of ATL. Aggressive subtypes of ATL are life-threatening and challenging to treat, with median overall survival typically less than 1 year in the absence of allogeneic hematopoietic cell transplantation (alloHCT). Owing to the rarity of this illness, prospective large-scale clinical trials have been challenging to perform, and treatment recommendations are largely founded upon limited evidence. Herein, we review the current therapeutic options for ATL, providing a broad literature overview of the foremost clinical trials and reports of this disease. We emphasize our own treatment paradigm, which is broadly based upon disease subtype, patient fitness, and intent to perform alloHCT. Finally, we highlight recent advances in understanding ATL disease biology and important ongoing clinical trials that we foresee as informative and potentially practice-changing.

Retrospective characterization of nodal marginal zone lymphoma.

Nodal marginal zone lymphoma (NMZL) is a rare non-Hodgkin B-cell lymphoma that has historically been difficult to define, though is now formally recognized by the World Health Organization Classification. To better characterize the clinical outcomes of patients with NMZL, we reviewed a sequential cohort of 187 patients with NMZL to describe baseline characteristics, survival outcomes, and time-to-event data. Initial management strategies were classified into five categories: observation, radiation, anti-CD20 monoclonal antibody therapy, chemoimmunotherapy, or other. Baseline Follicular Lymphoma International Prognostic Index scores were calculated to evaluate prognosis. A total of 187 patients were analyzed. The five-year overall survival was 91% (95% confidence interval [CI], 87-95), with a median follow-up time of 71 months (range, 8-253) among survivors. A total of 139 patients received active treatment at any point, with a median follow-up time of 56 months (range, 13-253) among survivors who were never treated. The probability of remaining untreated at five years was 25% (95% CI, 19-33). For those initially observed, the median time to active treatment was 72 months (95% CI, 49-not reached). For those who received at least one active treatment, the cumulative incidence of receiving a second active treatment at 60 months was 37%. Transformation to large B-cell lymphoma was rare, with a cumulative incidence of 15% at 10 years. In summary, our series is a large cohort of uniformly diagnosed NMZL with detailed analyses of survival and time to event analyses. We showed that NMZL commonly presents as an indolent lymphoma for which initial observation is often a reasonable strategy.

Final results of a phase II study of CHOEP plus lenalidomide as initial therapy for patients with stage II-IV peripheral T-cell lymphoma.

There remains no one standard induction for nodal-based peripheral T-cell lymphoma (PTCL). We conducted a phase II study of lenalidomide plus CHOEP as a novel induction strategy. Patients received CHOEP at standard doses in combination with 10 mg of lenalidomide on days 1-10 of a 21-day cycle for six cycles of therapy followed by observation, high-dose therapy with autologous stem cell rescue, or maintenance lenalidomide per provider preference. Among 39 patients evaluable for efficacy, the objective response rate after six cycles was 69%, with complete response in 49%, partial response in 21%, stable disease in 0% and progressive disease in 13%. Thirty-two patients (82%) completed full induction, and seven patients (18%) discontinued for toxicity, primarily hematologic. Any grade hematologic toxicity occurred in over 50% of patients, with grade 3 or 4 febrile neutropenia occurring in 35% of patients despite mandated growth factors. With a median followup of surviving patients of 21.3 months, the estimated 2-year progression-free and overall survival were 55% (95% CI 37%-70%) and 78% (95% CI 59%-89%), respectively. In sum, six cycles of lenalidomide plus CHOEP resulted in a modest response rate primarily due to hematologic toxicity, which prevented all patients from completing planned induction.

TP53 mutations identify high-risk events for peripheral T-cell lymphoma treated with CHOP-based chemotherapy.

Nodal peripheral T-cell lymphomas (PTCL), the most common PTCLs, are generally treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)-based curative-intent chemotherapy. Recent molecular data have assisted in prognosticating these PTCLs, but most reports lack detailed baseline clinical characteristics and treatment courses. We retrospectively evaluated cases of PTCL treated with CHOP-based chemotherapy that had tumors sequenced by the Memorial Sloan Kettering Integrated Mutational Profiling of Actionable Cancer Targets next-generation sequencing panel to identify variables correlating with inferior survival. We identified 132 patients who met these criteria. Clinical factors correlating with an increased risk of progression (by multivariate analysis) included advanced-stage disease and bone marrow involvement. The only somatic genetic aberrancies correlating with inferior progression-free survival (PFS) were TP53 mutations and TP53/17p deletions. PFS remained inferior when stratifying by TP53 mutation status, with a median PFS of 4.5 months for PTCL with a TP53 mutation (n = 21) vs 10.5 months for PTCL without a TP53 mutation (n = 111). No TP53 aberrancy correlated with inferior overall survival (OS). Although rare (n = 9), CDKN2A-deleted PTCL correlated with inferior OS, with a median of 17.6 months vs 56.7 months for patients without CDKN2A deletions. This retrospective study suggests that patients with PTCL with TP53 mutations experience inferior PFS when treated with curative-intent chemotherapy, warranting prospective confirmation.

Therapeutic Advances in Relapsed and Refractory Peripheral T-Cell Lymphoma.

Historic outcomes for patients with relapsed or refractory nodal-based T-cell lymphomas are poor, with survival generally measured in months in multiple reports from the late 20th and early 21st century. Until recently, salvage strategies have mostly been borrowed from other aggressive lymphomas. However, dedicated investigations into the pathogenesis of T-cell lymphomas have resulted in an outpouring of therapies that target these diseases in biologically rational strategies. In particular, an evolving appreciation of the multiple complex oncogenic pathways and epigenetic changes that underlie these diseases has led to numerous agents targeting these aberrancies. Moreover, large reports of salvage allogeneic stem cell transplants in T-cell lymphoma have now been published, showing that adaptive immunotherapy is a potentially curative strategy for patients with relapsed or refractory disease. This review highlights therapeutic advances for relapsed or refractory T-cell lymphomas, including cellular therapy and allogeneic stem cell transplant, and provides a framework for management.

Moving towards biologically informed treatment strategies for T-cell lymphomas.

The rarity and biological heterogeneity of the peripheral T-cell lymphomas has made subtype- and biomarker-driven approaches challenging to realize and even more challenging to evaluate in clinical practice. Out of necessity, treatment of T-cell lymphomas has historically been derivative of other aggressive lymphomas, utilizing intensive combination chemotherapy programs in the upfront setting and non-overlapping cytotoxic regimens upon relapse. However, due to tremendous work in understanding the oncogenic basis of these varied diseases, an increasing exploration of rational, targeted therapies is underway. Still, clinical successes have at times lagged behind pathobiological realizations, and there is an evolving need for biologically based, subtype-specific strategies in the clinic. Herein we propose a framework for future success that relies upon optimizing standard therapy in populations known to benefit from combination chemotherapy, building upon CHOP (or CHOP-like) induction with the CHOP + X model, exploring the use of targeted platforms in the relapsed and refractory setting, and designing biomarker-informed clinical trials that target-specific subhistologies and unique molecular subsets.

Comparative efficacy and tolerability of novel agents vs chemotherapy in relapsed and refractory T-cell lymphomas: a meta-analysis.

Optimal treatment strategies for (relapsed and refractory [R/R]) peripheral T-cell lymphoma (PTCL) have not been well defined, and with the approval of several novel single agents (SA), the comparative efficacy of combination chemotherapy (CC) to single-agent strategies remains unclear. We conducted a meta-analysis to evaluate overall response rates (ORR) and toxicities of SA to CC. MEDLINE, Embase, Web of Science Core Collection, and Cochrane were systematically searched for phase I, phase II, and phase III trials investigating a defined SA or an anthracycline-, ifosfamide-, gemcitabine-, and platinum-based regimens. One hundred and fifty-one articles were included, encompassing single and combinations of 60 phase I trials involving 1075 patients, 95 phase II trials involving 3246, and 23 phase III trials involving 1888 patients. There was a high degree of heterogeneity in the trials. Using a random-effects model, the estimated ORR for SA in phase I trials were 40% (95% confidence interval [CI], 34.7%, 46.9%) relative to 41% for CC (95% CI, 27.4%, 56.1%; P = .97) and in phase II trials 34.4% (95% CI, 30.4%, 38.7%) for SA vs 55.3% (95% CI, 31%, 77.2%; P = .1) for CC. There were significant subgroup differences in ORR between histological subtypes of PTCL and drug classes. Our results highlight SA as an attractive outpatient option for R/R PTCL, and their incorporation in the development of upfront treatment paradigms merits urgent consideration. Our results underscore enrollment in clinical trials of SA as a critical strategy for R/R PTCL.

Current Treatment of Peripheral T-cell Lymphoma.

The peripheral T-cell lymphomas (PTCLs) are a notoriously diverse family of non-Hodgkin lymphomas with generally aggressive biology. Clinical management is challenging given a largely inadequate literature base comprised of few randomized trials and heterogeneous observational reports. Herein, we provide an account of our practice in the treatment of the 3 most common nodal PTCLs: PTCL, not otherwise specified, angioimmunoblastic T-cell lymphoma, and anaplastic large cell lymphoma (ALCL). In the up-front setting, we employ anthracycline-based induction, with the incorporation of brentuximab vedotin for all those with ALCL and consideration in those with other CD30-expressing PTCLs based on improved progression-free and overall survival in the absence of additional toxicity in the ECHELON-2 trial. We strongly consider high-dose therapy with autologous stem cell rescue in first complete remission. In the relapsed or refractory (R/R) setting, we often look to clinical trials or choose from 4 FDA-approved single agents-belinostat, brentuximab vedotin, romidepsin, and pralatrexate-based on tumor phenotype and side-effect profiles. Our goal in the R/R setting is achievement of complete remission followed by allogeneic transplant with curative intent in appropriate candidates or long-term disease control in others. Numerous investigational agents are advancing through trials and have potential to alter standards of care in the near future.

Comparative outcomes for mature T-cell and NK/T-cell lymphomas in people with and without HIV and to AIDS-defining lymphomas.

There are no studies comparing the prognosis for mature T-cell lymphoma (TCL) in people with HIV (PWH) to people without HIV (PWoH) and to AIDS-defining B-cell lymphomas (A-BCLs) in the modern antiretroviral therapy era. North American AIDS Cohort Collaboration on Research and Design and Comprehensive Oncology Measures for Peripheral T-cell Lymphoma Treatment are cohorts that enroll patients diagnosed with HIV and TCL, respectively. In our study, 52, 64, 101, 500, and 246 PWH with histologic confirmation of TCL, primary central nervous system lymphoma, Burkitt's lymphoma, diffuse large B-cell lymphoma (DLBCL), and Hodgkin's lymphoma (HL), respectively, and 450 TCLs without HIV were eligible for analysis. At the time of TCL diagnosis, anaplastic large-cell lymphoma (ALCL) was the most common TCL subtype within PWH. Although PWH with TCL diagnosed between 1996 and 2009 experienced a low 5-year survival probability at 0.23 (95% confidence interval [CI]: 0.13, 0.41), we observed a marked improvement in their survival when diagnosed between 2010 and 2016 (0.69; 95% CI: 0.48, 1; P = .04) in contrast to TCLs among PWoH (0.45; 95% CI: 0.41, 0.51; P = .53). Similarly, PWH with ALCLs diagnosed between 1996 and 2009 were associated with a conspicuously inferior 5-year survival probability (0.17; 95% CI: 0.07, 0.42) and consistently lagged behind A-BCL subtypes such as Burkitt's (0.43; 95% CI:0.33, 0.57; P = .09) and DLBCL (0.17; 95% CI: 0.06, 0.46; P = .11) and behind HL (0.57; 95% CI: 0.50, 0.65; P < .0001). Despite a small number, those diagnosed between 2010 and 2016 experienced a remarkable improvement in survival (0.67; 95% CI: 0.3, 1) in comparison with PWoH (0.76; 95% CI: 0.66, 0.87; P = .58). Thus, our analysis confirms improved overall survival for aggressive B- and T-cell malignancies among PWH in the last decade.