Toxicities and outcome after CD19-directed chimeric antigen receptor T-cell therapy for secondary neurolymphomatosis.

Lymphomatous infiltration of the peripheral nervous system (PNS), termed neurolymphomatosis, represents a distinct extranodal non-Hodgkin lymphoma variant with dismal outcome. CD19-directed chimeric antigen receptor (CD19-CAR) T-cell therapy has emerged as a safe and effective treatment for B-cell lymphomas. We aimed to assess toxicity and efficacy of CD19-CAR T-cells in neurolymphomatosis. Neurolymphomatosis patients treated with CD19 CAR T-cells were retrospectively identified at Massachusetts General Hospital over a six-year period. Toxicities were graded according to the ASTCT classification, management, and response rates were recorded. Eleven neurolymphomatosis patients were identified with a median of 2 lines of PNS-directed treatments (range: 1-3) prior to receiving CD19-CAR T-cells. Neurolymphomatosis localized to the nerve roots (8/11, 73%), plexus (5/11, 45%), peripheral (4/11, 36%) and cranial nerves (5/11, 45%). Low grade cytokine release syndrome (CRS) was detected in 8/11 (73%; grade 1: N = 7; grade 2: N = 1) cases. Low- and high-grade immune cell-associated neurotoxicity syndrome (ICANS) were recorded in 5/11 (45%; grade 1: N = 4; grade 2: N = 1) and 1/11 (9%; grade 4) patients, respectively. CRP levels at infusion were predictive of ICANS (area under the curve: 0.96, p = 0.01). Seven of eleven neurolymphomatosis patients (64%) responded to CD19-CAR T-cells. Complete remissions (CR) were achieved in three cases (27%), with 2 patients in sustained CR nine and 46 months after CD19-CAR infusion. Median progression-free survival (PFS) was 4 months. Collectively, CD19-CAR T-cell treatment was well tolerated and showed promising efficacy in recurrent neurolymphomatosis, a difficult to treat condition with unmet medical need. Findings suggest that CD19-CAR may sufficiently penetrate the blood-nerve barrier. Toxicity and outcomes were overall similar to CAR-T cell therapy in CNS lymphoma.

Global outcomes and prognosis for relapsed/refractory mature T-cell and NK-cell lymphomas: Results from PETAL consortium.

Variances in global access to drugs and treatment practices make it challenging to understand the benefit of contemporary therapies in patients with relapsed and refractory (R/R) mature T-cell and NK-cell lymphomas (MTCL and MNKCL). We conducted an international retrospective cohort study of 925 patients with R/R MTCL and MNKCL. In PTCL-NOS and ALK- ALCL, patients with relapsed lymphoma demonstrated a superior median overall survival (OS) relative to refractory from the time of second-line treatment. We identified several independent predictors of OS for R/R lymphoma including age >60, primary refractory disease, histological subtype other than AITL, extranodal sites >1, Ki67 ≥40%, and absolute lymphocyte count

Zanubrutinib, Obinutuzumab, and Venetoclax for First-Line Treatment of Mantle Cell Lymphoma with a TP53 Mutation.

BACKGROUND: TP53-mutant mantle cell lymphoma (MCL) is associated with poor survival outcomes with standard chemoimmunotherapy. Dual BTK and BCL2-inhibition with or without anti-CD20 monoclonal antibody therapy has shown promising activity in TP53-mutant MCL. We conducted a multi-center phase 2 study of zanubrutinib, obinutuzumab, and venetoclax (BOVen) in untreated MCL patients with TP53 mutation. Patients initially received zanubrutinib 160mg twice daily and obinutuzumab. Obinutuzumab 1000mg was given on cycle 1 day 1, 8, 15 and day 1 of cycles 2-8. After 2 cycles, venetoclax was added with weekly dose-ramp up to 400mg daily. After 24 cycles, if patients were in complete remission with undetectable minimal residual disease using an immunosequencing assay, treatment was discontinued. The primary endpoint was met if ³11 patients were progression free at 2 years. The study included 25 patients with untreated MCL with TP53 mutation. The best overall response rate was 96% (24/25) and the complete response rate was 88% (22/25). Frequency of uMRD5 and uMRD6 at cycle 13 was 95% (18/19) and 84% (16/19). With median follow up of 28.2 months, the primary endpoint was met with a 2-year progression-free survival of 72%, and the 2-year disease-specific and overall survival were 91% and 76%, respectively. Common side effects were generally low grade and included diarrhea (64%), neutropenia (32%), and infusion-related reactions (24%). BOVen was well tolerated and met its primary efficacy endpoint in TP53-mutant mantle cell lymphoma. These data support its use and further evaluation of the BOVen regimen in this high-risk population. NCT03824483.

Effect of atorvastatin versus placebo on efficacy in patients with diffuse large B-cell lymphoma receiving R-CHOP.

STOP-CA was a multicenter, double-blind, randomized, placebo-controlled trial comparing atorvastatin to placebo in treatment-naïve lymphoma patients receiving anthracycline-based chemotherapy. We performed a preplanned subgroup to analyze the impact of atorvastatin on efficacy in patients with diffuse large B-cell lymphoma (DLBCL). Patients received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) at standard doses for six 21-day cycles and were randomly assigned to receive atorvastatin 40 mg daily (n = 55) or placebo (n = 47) for 12 months. The complete response (CR) rate was numerically higher in the atorvastatin arm (95% [52/55] vs. 85% [40/47], p = .18), but this was not statistically significant. Adverse event rates were similar between the atorvastatin and placebo arms. In summary, atorvastatin did not result in a statistically significant improvement in the CR rate or progression-free survival, but both were numerically improved in the atorvastatin arm. These data warrant further investigation into the potential therapeutic role of atorvastatin added to anthracycline-based chemotherapies.

KLRG1 Cell Depletion as a Novel Therapeutic Strategy in Patients with Mature T-Cell Lymphoma Subtypes.

PURPOSE: Develop a novel therapeutic strategy for patients with subtypes of mature T-cell and NK-cell neoplasms. EXPERIMENTAL DESIGN: Primary specimens, cell lines, patient-derived xenograft models, commercially available, and proprietary anti-KLRG1 antibodies were used for screening, target, and functional validation. RESULTS: Here we demonstrate that surface KLRG1 is highly expressed on tumor cells in subsets of patients with extranodal NK/T-cell lymphoma (ENKTCL), T-prolymphocytic leukemia (T-PLL), and gamma/delta T-cell lymphoma (G/D TCL). The majority of the CD8+/CD57+ or CD3-/CD56+ leukemic cells derived from patients with T- and NK-large granular lymphocytic leukemia (T-LGLL and NK-LGLL), respectively, expressed surface KLRG1. The humanized afucosylated anti-KLRG1 monoclonal antibody (mAb208) optimized for mouse in vivo use depleted KLRG1+ TCL cells by mechanisms of ADCC, ADCP, and CDC rather than apoptosis. mAb208 induced ADCC and ADCP of T-LGLL patient-derived CD8+/CD57+ cells ex vivo. mAb208 effected ADCC of subsets of healthy donor-derived KLRG1+ NK, CD4+, CD8+ Tem, and TemRA cells while sparing KLRG1- naïve and CD8+ Tcm cells. Treatment of cell line and TCL patient-derived xenografts with mAb208 or anti-CD47 mAb alone and in combination with the PI3K-δ/γ inhibitor duvelisib extended survival. The depletion of macrophages in vivo antagonized mAb208 efficacy. CONCLUSIONS: Our findings suggest the potential benefit of a broader treatment strategy combining therapeutic antibodies with PI3Ki for the treatment of patients with mature T-cell and NK-cell neoplasms. See related commentary by Varma and Diefenbach, p. 2300.

Neurotoxicity and management of primary and secondary central nervous system lymphoma after adoptive immunotherapy with CD19-directed chimeric antigen receptor T-cells.

BACKGROUND: Chimeric antigen receptor (CAR) T-cells targeting CD19 have been established as a leading engineered T-cell therapy for B-cell lymphomas; however, data for patients with central nervous system (CNS) involvement are limited. METHODS: We retrospectively report on CNS-specific toxicities, management, and CNS response of 45 consecutive CAR T-cell transfusions for patients with active CNS lymphoma at the Massachusetts General Hospital over a 5-year period. RESULTS: Our cohort includes 17 patients with primary CNS lymphoma (PCNSL; 1 patient with 2 CAR T-cell transfusions) and 27 patients with secondary CNS lymphoma (SCNSL). Mild ICANS (grade 1-2) was observed after 19/45 transfusions (42.2%) and severe immune effector cell-associated neurotoxicity syndrome (ICANS) (grade 3-4) after 7/45 transfusions (15.6%). A larger increase in C-reactive protein (CRP) levels and higher rates of ICANS were detected in SCNSL. Early fever and baseline C-reactive protein levels were associated with ICANS occurrence. CNS response was seen in 31 cases (68.9%), including a complete response of CNS disease in 18 cases (40.0%) which lasted for a median of 11.4 ±â€…4.5 months. Dexamethasone dose at time of lymphodepletion (but not at or after CAR T-cell transfusion) was associated with an increased risk for CNS progression (hazard ratios [HR] per mg/d: 1.16, P = .031). If bridging therapy was warranted, the use of ibrutinib translated into favorable CNS-progression-free survival (5 vs. 1 month, HR 0.28, CI 0.1-0.7; P = .010). CONCLUSIONS: CAR T-cells exhibit promising antitumor effects and a favorable safety profile in CNS lymphoma. Further evaluation of the role of bridging regimens and corticosteroids is warranted.

Brentuximab vedotin plus doxorubicin and dacarbazine in nonbulky limited-stage classical Hodgkin lymphoma.

ABVD (Adriamycin, bleomycin, vinblastine, dacarbazine) with or without radiation has been the standard treatment for limited-stage Hodgkin lymphoma (HL) but carries risks of bleomycin lung injury and radiation toxicity. Brentuximab vedotin (BV) is approved with AVD for stage III-IV HL, but carries increased risks of peripheral neuropathy (PN) and neutropenic fever, likely due to overlapping toxicity between BV and vinblastine. We therefore evaluated BV in combination with AD for 4 or 6 cycles based on interim positron emission tomography response. Thirty-four patients with nonbulky stage I-II HL were enrolled. Risk was early favorable in 53% and unfavorable in 47%. The overall and complete response rates (CRRs) were 100% and 97%, respectively, with a 5-year progression-free survival (PFS) of 91%. No differences in outcome were observed based on stage (I vs II) or risk status (early favorable vs unfavorable). The most common adverse events were nausea (85%), peripheral sensory neuropathy (59%), and fatigue (56%). There were no cases of grade-4 neutropenia or neutropenic fever, and no patient received granulocyte-colony stimulating factor. Most cases of PN were grade 1, and no patient experienced grade ≥3 PN. BV-AD produced a high CRR and durable PFS with most patients requiring 4 cycles of therapy. Compared with BV-AVD, the toxicity profile appeared improved, with predominantly grade 1 reversible PN and no case of grade 4 neutropenia or neutropenic fever. This regimen warrants further study in HL and may serve as a backbone for the addition of novel agents. This trial is registered on clinicaltrials.gov (NCT02505269).

Odronextamab, a human CD20×CD3 bispecific antibody in patients with CD20-positive B-cell malignancies (ELM-1): results from the relapsed or refractory non-Hodgkin lymphoma cohort in a single-arm, multicentre, phase 1 trial.

BACKGROUND: Odronextamab is a hinge-stabilised, fully human IgG4-based CD20 × CD3 bispecific antibody that binds CD3 on T cells and CD20 on B cells. We aimed to evaluate the safety and antitumour activity of odronextamab in patients with relapsed or refractory B-cell non-Hodgkin lymphoma. METHODS: This single-arm, multicentre, phase 1, dose-escalation and dose-expansion (ELM-1) trial was conducted at ten academic sites across the USA and Germany. Patients aged 18 years or older with CD20-positive relapsed or refractory B-cell malignancies who previously received CD20-directed antibody therapy and who had at least one measurable lesion, and an ECOG performance status of 0 or 1 were included. Patients received intravenous odronextamab, according to a step-up dosing schedule in cycle 1, followed by treatment once per week at target doses ranging from 0·1 mg to 320 mg during cycles 2-4 (each cycle was 21 days). After cycle 4, maintenance treatment occurred every 2 weeks until disease progression or unacceptable toxicity. The primary endpoint of safety was assessed by the incidence of adverse events and dose-limiting toxicities to determine the maximum tolerated dose or phase 2 dose of odronextamab, or both. Preliminary antitumour activity, as measured by objective response rate, was a secondary endpoint. This study is registered with ClinicalTrials.gov, NCT02290951. FINDINGS: From Feb 4, 2015, to Sept 25, 2021, 145 heavily pretreated patients (median of 3 (IQR 2-5] previous therapies) were enrolled (94 to the dose-escalation and 51 to the dose-expansion part of the study). The median age of patients was 67·0 years (IQR 57·0-73·0); 101 (70%) were male and 44 (30%) were female; most participants were White (119 [82%]) and not Hispanic or Latino (132 [91%]). 42 (29%) patients received previous CAR T therapy and 119 (82%) were refractory to the last line of therapy. Median duration of follow-up was 4·2 months (IQR 1·5-11·5). During dose escalation, odronextamab was administered up to the maximum dose of 320 mg once per week and no dose-limiting toxicities were observed. The recommended dose for expansion in patients with follicular lymphoma grade 1-3a was 80 mg and was 160 mg for patients with diffuse large B-cell lymphoma. Cytokine release syndrome and neurological treatment-emergent adverse events were predominantly low grade and did not result in treatment discontinuation. The most common grade 3 or worse treatment-emergent adverse events were anaemia (36 [25%]), lymphopenia (28 [19%]), hypophosphataemia (27 [19%]), neutropenia (27 [19%]), and thrombocytopenia (20 [14%]). Serious treatment-emergent adverse events occurred in 89 (61%) of 145 patients; the most frequent were cytokine release syndrome (41 [28%]), pyrexia (11 [8%]), pneumonia (nine [6%]), and infusion-related reaction (six [4%]). Four deaths were considered related to treatment (gastric perforation in a patient with gastric involvement by lymphoma, lung infection, pneumonia, and tumour-lysis syndrome). Objective response rate was 51% (95% CI 42-59; 72 of 142). In patients with follicular lymphoma who received odronextamab doses of 5 mg or higher, the objective response rate was 91% (95% CI 75-98; 29 of 32) and the complete response rate was 72% (95% CI 53-86; 23 of 32). In patients with diffuse large B-cell lymphoma without previous CAR T-cell therapy who received doses of 80 mg or higher, the objective response rate was 53% (eight of 15) and all responses were complete responses. In patients with diffuse large B-cell lymphoma who had previous CAR T-cell therapy and received doses of 80 mg or higher, the objective response rate was 33% (ten of 30) and complete response rate was 27% (eight of 30). INTERPRETATION: Odronextamab monotherapy showed a manageable safety profile and encouraging preliminary activity, including durable responses in heavily pretreated patients with B-cell non-Hodgkin lymphoma, supporting further clinical investigation in phase 2 and 3 trials. FUNDING: Regeneron Pharmaceuticals.

Humoral and cellular immunogenicity of SARS-CoV-2 vaccines in chronic lymphocytic leukemia: a prospective cohort study.

Chronic lymphocytic leukemia (CLL), the most common leukemia worldwide, is associated with increased COVID-19 mortality. Previous studies suggest only a portion of vaccinated CLL patients develop severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antibodies. Whether the elicited antibodies are functional and/or accompanied by functional T-cell responses is unknown. This prospective cohort study included patients with CLL who received SARS-CoV-2 and PCV13 vaccines (not concurrently). The primary cohort included adults with CLL off therapy. Coprimary outcomes were serologic response to SARS-CoV-2 (receptor binding domain [RBD] immunoassay) and PCV13 vaccines (23-serotype IgG assay). Characterization of SARS-CoV-2 antibodies and their functional activity and assessment of functional T-cell responses was performed. Sixty percent (18/30) of patients demonstrated serologic responses to SARS-CoV-2 vaccination, appearing more frequent among treatment-naïve patients (72%). Among treatment-naïve patients, an absolute lymphocyte count ≤24 000/µL was associated with serologic response (94% vs 14%; P < .001). On interferon-γ release assays, 80% (16/20) of patients had functional spike-specific T-cell responses, including 78% (7/9) with a negative RBD immunoassay, a group enriched for prior B-cell-depleting therapies. A bead-based multiplex immunoassay identified antibodies against wild-type and variant SARS-CoV-2 (α, ß, γ, and δ) in all tested patients and confirmed Fc-receptor binding and effector functions of these antibodies. Of 11 patients with negative RBD immunoassay after vaccination, 6 (55%) responded to an additional mRNA-based vaccine dose. The PCV13 serologic response rate was 29% (8/28). Our data demonstrate that SARS-CoV-2 vaccination induces functional T-cell and antibody responses in patients with CLL and provides the framework for investigating the molecular mechanisms and clinical benefit of these responses. This trial was registered at www.clinicaltrials.gov as #NCT05007860.

Zanubrutinib, obinutuzumab, and venetoclax with minimal residual disease-driven discontinuation in previously untreated patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma: a multicentre, single-arm, phase 2 trial.

BACKGROUND: We hypothesised that combining zanubrutinib with obinutuzumab and venetoclax (BOVen) as an initial therapy for chronic lymphocytic leukaemia and small lymphocytic lymphoma would lead to high rates of undetectable minimal residual disease (MRD), and we explored MRD as a biomarker for directing treatment duration. METHODS: This multicenter, investigator-initiated, single-arm, phase 2 trial took place at two two academic medical centres in the USA. Patients were eligible for the primary cohort if they had treatment-naive chronic lymphocytic leukaemia or small lymphocytic lymphoma, required therapy, and were at least 18 years of age with an Eastern Cooperative Oncology Group performance status up to 2. BOVen was administered in 28 day cycles (oral zanubrutinib at 160 mg twice per day starting in cycle 1 on day 1; intravenous obinutuzumab at 1000 mg on day 1 [split over day 1 with 100 mg and day 2 with 900 mg for an absolute lymphocyte count >25 000 cells per µL or lymph nodes >5 cm in diameter], day 8, and day 15 of cycle 1, and day 1 of cycles 2-8; and oral venetoclax ramp up to 400 mg per day starting in cycle 3 on day 1) and discontinued after 8-24 cycles when prespecified undetectable MRD criteria were met in the peripheral blood and bone marrow. The primary endpoint was the proportion of patients that reached undetectable MRD in both the peripheral blood and bone marrow (flow cytometry cutoff less than one chronic lymphocytic leukaemia cell per 10 000 leukocytes [<10-4]) assessed per protocol. This trial is registered at clinicaltrials.gov (NCT03824483). The primary cohort is closed to recruitment, and recruitment continues in the TP53-mutated mantle cell lymphoma cohort. FINDINGS: Between March 14, 2019, and Oct 10, 2019, 47 patients were screened for eligibility, and 39 patients were enrolled and treated. Median age was 62 years (IQR 52-70) with 30 (77%) of 39 male participants and nine (23%) of 39 female participants. 28 (72%) of 39 patients had unmutated immunoglobulin heavy-chain variable-region and five (13%) of 39 had 17p deletion or TP53 mutation. After a median follow-up of 25·8 months (IQR 24·0-27·3), 33 (89%) of 37 patients (95% CI 75-97) had undetectable MRD in both blood and bone marrow, meeting the prespecified undetectable MRD criteria to stop therapy after a median of ten cycles (IQR 8-12), which includes two cycles of zanubrutinib and obinutuzumab before starting venetoclax. After median surveillance after treatment of 15·8 months (IQR 13·0-18·6), 31 (94%) of 33 patients had undetectable MRD. The most common adverse events were thrombocytopenia (23 [59%] of 39), fatigue (21 [54%]), neutropenia (20 [51%]), and bruising (20 [51%]), and the most common adverse event at grade 3 or worse was neutropenia (seven [18%]) in the intention-to-treat population. One death occurred in a patient with intracranial haemorrhage on day 1 of cycle 1 after initiating intravenous heparin for pulmonary emboli. INTERPRETATION: BOVen was well tolerated and met its primary endpoint, with 33 (89%) of 37 previously untreated patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma reaching undetectable MRD in both peripheral blood and bone marrow despite a median treatment duration of only 10 months, owing to our undetectable MRD-driven treatment discontinuation design. These data support further evaluation of the BOVen regimen in chronic lymphocytic leukaemia and small lymphocytic lymphoma with treatment duration guided by early MRD response kinetics. FUNDING: Beigene, Genentech (Roche), Grais-Cutler Fund, Lymphoma Research Fund, Lymphoma Research Foundation, American Cancer Society, Farmer Family Foundation, and the National Instititutes of Health and National Cancer Institute.

Brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine for nonbulky limited-stage classical Hodgkin lymphoma.

Doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) with or without radiation is standard therapy for limited-stage Hodgkin lymphoma (HL) but carries risks of bleomycin-induced lung injury and radiation toxicity. Brentuximab vedotin is highly active in relapsed HL and was recently approved with doxorubicin, vinblastine, and dacarbazine (AVD) for previously untreated stage III/IV HL. We evaluated brentuximab-AVD for nonbulky stage I/II HL in a multicenter phase 2 study. Patients received a lead-in cycle of brentuximab vedotin monotherapy on days 1 and 15, followed by an exploratory positron emission tomography/computed tomography scan. Patients then received brentuximab-AVD for 4 to 6 cycles based on interim positron emission tomography/computed tomography scanning after cycle 2. Thirty-four patients were enrolled with a median age of 36 years (range, 20-75 years). Risk was early favorable in 62% and unfavorable in 38%. The best complete response rate was 100%. At a median follow-up of 38 months, the progression-free survival and overall survival were 94% and 97%, respectively. The most common adverse events were peripheral sensory neuropathy (79%), neutropenia (76%), fatigue (74%), and nausea (71%). The most common grade 3/4 toxicities were neutropenia (62%), febrile neutropenia (35%), and peripheral sensory neuropathy (24%). One elderly patient died of neutropenic sepsis in the first brentuximab-AVD cycle. Brentuximab dose reductions were required in 38% of patients, most for peripheral neuropathy. In conclusion, brentuximab-AVD without bleomycin or radiation produced a high complete response rate, with most patients requiring only 4 total cycles of therapy. Because toxicity was higher than would be expected from AVD alone, this method may not be appropriate for early-stage patients with a highly favorable prognosis. This trial was registered at www.clinicaltrials.gov as #NCT01534078.

Clinical presentation, management, and biomarkers of neurotoxicity after adoptive immunotherapy with CAR T cells.

Chimeric antigen receptor (CAR) T cells have emerged as a promising class of cell-based immunotherapy in refractory malignancies. Neurotoxicity represents a common and potentially life-threatening adverse effect of CAR T cells, and clinical experience is limited. Here, we describe the clinical presentation and management of 25 adult patients who presented with neurotoxic syndromes after CAR T-cell therapy at the Massachusetts General Hospital. This cohort includes 24 patients treated with CD19-directed CAR T cells for non-Hodgkin lymphoma (n = 23) and acute lymphoblastic leukemia (n = 1), and 1 patient treated with α-fetoprotein-directed CAR T cells for hepatocellular carcinoma (n = 1). Twelve of the 25 patients (48%) developed grade 1-2 neurotoxicity and 13 patients (52%) presented with grade 3-4 neurotoxicity. We found that lower platelet counts at time of CAR T-cell infusion were associated with more severe neurotoxicity (P = .030). Cytokine release syndrome occurred in 24 of 25 patients (96%). Serum levels of ferritin peaked with onset of neurologic symptoms, and higher ferritin levels were associated with higher neurotoxicity grade. Grade 3-4 neurotoxicity correlated negatively with overall survival (OS) (P = .013). Median OS of the entire cohort was 54.7 weeks. Eight patients (32%) with grade 3-4 neurotoxicity were deceased at database closure, whereas none died with neurotoxicity grade 1-2. High pretreatment lactate dehydrogenase was frequently encountered in lymphoma patients with grade 3-4 neurotoxicity and correlated negatively with progression-free survival (P = .048). We did not find evidence that steroid use ≥7 days altered the patient's outcome when compared with <7 days of steroids. Management of CAR T cell-mediated neurotoxicity warrants evaluation in prospective clinical trials.

Panobinostat in combination with rituximab in heavily pretreated diffuse large B-cell lymphoma: Results of a phase II study.

This is a phase II study of panobinostat, an oral pan-HDAC inhibitor, combined with rituximab in patients with relapsed diffuse large B cell lymphoma. Panobinostat was administered orally 3 times a week every other week on a 28-day cycle. Rituximab was administered weekly during the first cycle, then on Day 1 of cycles 2 to 6. Patients without disease progression after 6 cycles continued panobinostat monotherapy for up to 6 additional cycles in the absence of disease progression. Eighteen eligible subjects were enrolled, and 18 were evaluable for response. The overall response rate was 11% (90% CI [2%-34%]) with 2 subjects having a partial response. The duration of response in these subjects was 51 and 60 days. Five additional subjects had stable disease with 3 subjects having tumor reduction between 27 and 44%, not meeting criteria for partial response. One subject with stable disease remained on therapy a total of 12 cycles. The most common toxicities while on study were thrombocytopenia (14 patients, 78%); fatigue (11, 61%); anemia (10, 56%); diarrhea (8, 44%); and nausea, lymphopenia, anorexia, and hypophosphatemia (5 each, 28% of patients), the majority of which was grade 2 or less. These data indicate that the combination of panobinostat with rituximab is able to induce responses in a limited number of subjects with relapsed diffuse large B cell lymphoma.

Projected Effects of Radiation-Induced Cancers on Life Expectancy in Patients Undergoing CT Surveillance for Limited-Stage Hodgkin Lymphoma: A Markov Model.

OBJECTIVE: Patients with limited-stage Hodgkin lymphoma (HL) undergo frequent posttreatment surveillance CT examinations, raising concerns about the cumulative magnitude of radiation exposure. The purpose of this study was to project radiation-induced cancer risks relative to competing risks of HL and account for the differential timing of each. MATERIALS AND METHODS: We adapted a previously developed Markov model to project lifetime mortality risks and life expectancy losses due to HL versus radiation-induced cancers in HL patients undergoing surveillance CT. In the base case, we modeled 35-year-old men and women undergoing seven CT examinations of the chest, abdomen, and pelvis over 5 years. Radiation-induced cancer risks and deaths for 17 organ systems were modeled using an organ-specific approach, accounting for specific anatomy exposed at CT. Cohorts of 20-, 50-, and 65-year-old men and women were evaluated in secondary analyses. Markov chain Monte Carlo methods were used to estimate the uncertainty of radiation risk projections. RESULTS: For 35-year-old adults, we projected 3324/100,000 (men) and 3345/100,000 (women) deaths from recurrent lymphoma and 245/100,000 (men, 95% uncertainty interval [UI]: 121-369) and 317/100,000 (women, 95% UI: 202-432) radiation-induced cancer deaths. Discrepancies in life expectancy losses between HL (428 days in men, 482 days in women) and radiation-induced cancers (11.6 days in men, [95% UI: 5.7-17.5], 15.6 days in women [95% UI: 9.8-21.4]) were proportionately greater because of the delayed timing of radiation-induced cancers relative to recurrent HL. Deaths and life expectancy losses from radiation-induced cancers were highest in the youngest cohorts. CONCLUSION: Given the low rate of radiation-induced cancer deaths associated with CT surveillance, modest CT benefits would justify its use in patients with limited-stage HL.

Treatment of primary mediastinal B-cell lymphoma with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone is associated with a high rate of primary refractory disease.

The optimal therapy for primary mediastinal B-cell lymphoma is a subject of ongoing debate, with no accepted standard of care. We performed a retrospective analysis of 63 patients in the modern era treated with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP), with or without radiation. Median age was 37 years (range 20-82). Eighty percent had limited stage disease and 71% were bulky. By age-adjusted International Prognostic Index (IPI), 15% were low-risk, 52% low-intermediate, 27% high-intermediate and 6% high-risk. Some 77% of responding patients received consolidative radiotherapy. Overall and complete response rates were 79% and 71%. Primary induction failure occurred in 13 (21%) patients. Five-year PFS and OS were 68% and 79%, respectively. Adverse prognostic features included increased IPI, advanced stage, advanced age and multiple extranodal sites. These data demonstrate an unacceptably high rate of primary refractory disease on R-CHOP, particularly among patients with high-risk features. Novel treatment approaches are needed that reduce primary refractory disease and reliance on mediastinal radiation in young people.