Bendamustine is safe and effective for lymphodepletion before tisagenlecleucel in patients with refractory or relapsed large B-cell lymphomas.

BACKGROUND: Anti-CD19 chimeric antigen receptor T-cell immunotherapy (CAR-T) is now a standard treatment of relapsed or refractory B-cell non-Hodgkin lymphomas; however, a significant portion of patients do not respond to CAR-T and/or experience toxicities. Lymphodepleting chemotherapy is a critical component of CAR-T that enhances CAR-T-cell engraftment, expansion, cytotoxicity, and persistence. We hypothesized that the lymphodepletion regimen might affect the safety and efficacy of CAR-T. PATIENTS AND METHODS: We compared the safety and efficacy of lymphodepletion using either fludarabine/cyclophosphamide (n = 42) or bendamustine (n = 90) before tisagenlecleucel in two cohorts of patients with relapsed or refractory large B-cell lymphomas treated consecutively at three academic institutions in the United States (University of Pennsylvania, n = 90; Oregon Health & Science University, n = 35) and Europe (University of Vienna, n = 7). Response was assessed using the Lugano 2014 criteria and toxicities were assessed by the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and, when possible, the American Society for Transplantation and Cellular Therapy (ASTCT) consensus grading. RESULTS: Fludarabine/cyclophosphamide led to more profound lymphocytopenia after tisagenlecleucel infusion compared with bendamustine, although the efficacy of tisagenlecleucel was similar between the two groups. We observed significant differences, however, in the frequency and severity of adverse events. In particular, patients treated with bendamustine had lower rates of cytokine release syndrome and neurotoxicity. In addition, higher rates of hematological toxicities were observed in patients receiving fludarabine/cyclophosphamide. Bendamustine-treated patients had higher nadir neutrophil counts, hemoglobin levels, and platelet counts, as well as a shorter time to blood count recovery, and received fewer platelet and red cell transfusions. Fewer episodes of infection, neutropenic fever, and post-infusion hospitalization were observed in the bendamustine cohort compared with patients receiving fludarabine/cyclophosphamide. CONCLUSIONS: Bendamustine for lymphodepletion before tisagenlecleucel has efficacy similar to fludarabine/cyclophosphamide with reduced toxicities, including cytokine release syndrome, neurotoxicity, infectious and hematological toxicities, as well as reduced hospital utilization.

International Working Group consensus response evaluation criteria in lymphoma (RECIL 2017).

In recent years, the number of approved and investigational agents that can be safely administered for the treatment of lymphoma patients for a prolonged period of time has substantially increased. Many of these novel agents are evaluated in early-phase clinical trials in patients with a wide range of malignancies, including solid tumors and lymphoma. Furthermore, with the advances in genome sequencing, new "basket" clinical trial designs have emerged that select patients based on the presence of specific genetic alterations across different types of solid tumors and lymphoma. The standard response criteria currently in use for lymphoma are the Lugano Criteria which are based on [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography or bidimensional tumor measurements on computerized tomography scans. These differ from the RECIST criteria used in solid tumors, which use unidimensional measurements. The RECIL group hypothesized that single-dimension measurement could be used to assess response to therapy in lymphoma patients, producing results similar to the standard criteria. We tested this hypothesis by analyzing 47 828 imaging measurements from 2983 individual adult and pediatric lymphoma patients enrolled on 10 multicenter clinical trials and developed new lymphoma response criteria (RECIL 2017). We demonstrate that assessment of tumor burden in lymphoma clinical trials can use the sum of longest diameters of a maximum of three target lesions. Furthermore, we introduced a new provisional category of a minor response. We also clarified response assessment in patients receiving novel immune therapy and targeted agents that generate unique imaging situations.

Optimal sequencing of ibrutinib, idelalisib, and venetoclax in chronic lymphocytic leukemia: results from a multicenter study of 683 patients.

Background: Ibrutinib, idelalisib, and venetoclax are approved for treating CLL patients in the United States. However, there is no guidance as to their optimal sequence. Patients and methods: We conducted a multicenter, retrospective analysis of CLL patients treated with kinase inhibitors (KIs) or venetoclax. We examined demographics, discontinuation reasons, overall response rates (ORR), survival, and post-KI salvage strategies. Primary endpoint was progression-free survival (PFS). Results: A total of 683 patients were identified. Baseline characteristics were similar in the ibrutinib and idelalisib groups. ORR to ibrutinib and idelalisib as first KI was 69% and 81%, respectively. With a median follow-up of 17 months (range 1-60), median PFS and OS for the entire cohort were 35 months and not reached. Patients treated with ibrutinib (versus idelalisib) as first KI had a significantly better PFS in all settings; front-line [hazard ratios (HR) 2.8, CI 1.3-6.3, P = 0.01], relapsed-refractory (HR 2.8, CI 1.9-4.1, P < 0.001), del17p (HR 2.0, CI 1.2-3.4, P = 0.008), and complex karyotype (HR 2.5, CI 1.2-5.2, P = 0.02). At the time of initial KI failure, use of an alternate KI or venetoclax had a superior PFS when compared with chemoimmunotherapy. Furthermore, patients who discontinued ibrutinib due to progression or toxicity had marginally improved outcomes if they received venetoclax (ORR 79%) versus idelalisib (ORR 46%) (PFS HR .6, CI.3-1.0, P = 0.06). Conclusions: In the largest real-world experience of novel agents in CLL, ibrutinib appears superior to idelalisib as first KI. Furthermore, in the setting of KI failure, alternate KI or venetoclax therapy appear superior to chemoimmunotherapy combinations. The use of venetoclax upon ibrutinib failure might be superior to idelalisib. These data support the need for trials testing sequencing strategies to optimize treatment algorithms.

Clinical experience with lenalidomide alone or in combination with rituximab in indolent B-cell and mantle cell lymphomas.

Lenalidomide is an oral immunomodulatory drug with significant activity in indolent B-cell and mantle cell lymphomas. Lenalidomide has a manageable safety profile whether administered as a single agent or in combination with rituximab. The combination of lenalidomide with rituximab, known as the 'R(2)' regimen, enhances efficacy over what has been shown with monotherapy and has demonstrated activity in patients considered resistant to rituximab. Tolerability of these regimens has been consistent among studies. Asymptomatic neutropenia is the most common grade 3/4 adverse event, typically managed by dose interruption, followed by dose reduction once neutrophils have recovered. Nonhematologic toxicities (e.g. fatigue) are generally low-grade, manageable with concomitant treatment, and/or lenalidomide dose modification. More frequent with R(2), immune-related symptoms such as rash and tumor flare are important to recognize as lenalidomide-associated treatment effects in patients with lymphoma who require supportive care and potential dose modifications. Severe tumor flare reactions with painful lymphadenopathy are not typically observed outside of chronic lymphocytic leukemia/small lymphocytic lymphoma. Venous thromboembolism is uncommon in lymphomas, though prophylaxis is recommended. The general safety profile, differences between lenalidomide monotherapy and R(2) treatment, and optimal strategies for managing adverse events are discussed here.

The Impact of EBV Status on Characteristics and Outcomes of Posttransplantation Lymphoproliferative Disorder.

We examined the associations of Epstein-Barr virus (EBV) status with characteristics and outcomes of posttransplantation lymphoproliferative disorder (PTLD) by studying 176 adult solid organ transplant recipients diagnosed with PTLD between 1990 and 2013 (58 [33%] EBV-negative; 118 [67%] EBV-positive). The proportion of EBV-negative cases increased over time from 10% (1990-1995) to 48% (2008-2013) (p < 0.001). EBV-negative PTLD had distinct characteristics (monomorphic histology, longer latency) though high-risk features (advanced stage, older age, high lactate dehydrogenase, central nervous system involvement) were not more common compared to EBV-positive PTLD. In multivariable analysis, EBV negativity was not significantly associated with worse response to initial therapy (adjusted odds ratio, 0.84; p = 0.75). The likelihood of achieving a complete remission (CR) was not significantly different for EBV-negative versus EBV-positive PTLD including when therapy was reduction of immunosuppression alone (35% vs. 43%, respectively, p = 0.60) or rituximab (43% vs. 47%, p = 1.0). EBV negativity was also not associated with worse overall survival (adjusted hazard ratio, 0.91; p = 0.71). Our findings indicate that EBV status is not prognostic or predictive of treatment response in adults with PTLD. The high proportion of EBV-negative disease diagnosed in recent years highlights the need for new strategies for prevention and management of EBV-negative PTLD.

Potential prolongation of PFS in mantle cell lymphoma after R-HyperCVAD: auto-SCT consolidation or rituximab maintenance.

We retrospectively analyzed 44 patients undergoing first-line treatment for mantle cell lymphoma with R-HyperCVAD, with or without rituximab (R) maintenance or auto-SCT. The primary study end point was PFS; secondary end point was overall survival.Median follow up for all patients was 3.3 years. Median age was 54 years, and 95% (n=42) were stage III or IV at diagnosis. In all, 17 patients underwent consolidative auto-SCT and 12 patients received R maintenance. The overall response rate was 95%, with 91% achieving complete response (CR). Median PFS for all patients was 3.5 years. Median PFS was 2.3 years for patients treated with R-HyperCVAD alone vs 3.9 years (P=0.02) with R-HyperCVAD+ R maintenance and 4.5 years (P=0.01) with R-HyperCVAD+ auto-SCT. For patients who did not achieve CR at interim staging, PFS for R-HyperCVAD alone was 1.4 years vs not reached for R-HyperCVAD+ consolidation (either R maintenance or auto-SCT) (P=0.02). PFS for patients with CR at interim staging was 3.3 years vs not reached (P=0.04) after consolidation. Our data suggest potential improvement in PFS when R-HyperCVAD is consolidated with either R maintenance or auto-SCT. This benefit appears particularly significant in those patients who do not achieve CR at interim restaging.

Second auto-SCT is safe and effective salvage therapy for relapsed multiple myeloma.

Therapeutic options for patients with multiple myeloma whose disease has relapsed after a prior auto-SCT include novel biologic therapies, traditional chemotherapy or a second transplant, with no clear standard of care. Few published studies address the safety and efficacy of a second auto-SCT for relapsed disease. We reviewed the Abramson Cancer Center experience with salvage auto-SCT for relapsed multiple myeloma. Forty-one patients had received a salvage auto-SCT at our institution; the median time between transplants was 37 months (range 3-91). The overall response rate in assessable patients was 55%, and treatment-related mortality was 7%. With a median follow-up time of 15 months, the median PFS was 8.5 months and the median overall survival (OS) was 20.7 months. In a multivariate analysis of OS, independent prognostic factors were >or=5 prior lines of therapy and time to progression after initial auto-SCT of

EBV PCR in the diagnosis and monitoring of posttransplant lymphoproliferative disorder: results of a two-arm prospective trial.

While EBV PCR is used in the management of PTLD, the optimal primer set, relative importance of intracellular versus free plasma EBV, and the baseline profile in an organ transplant population remains unclear. We performed a prospective 2-arm trial utilizing an EBV PCR panel measuring LMP-1, EBER-1 and EBNA-1 in both free plasma as well as intracellular whole blood. Control Arm A consisted of 31 lung transplant patients and Arm B consisted of 35 transplant patients being evaluated for possible PTLD. In Arm A, 1/31 (3%) patients developed a transient plasma EBV load. Thirteen of 31 (42%) had detectable intracellular EBV. In Arm B, 17 (49%) patients were diagnosed with PTLD. Thirteen (76%) had EBV-positive PTLD with 12/13 (92%) having detectable EBV by PCR. The EBV PCR panel had a high sensitivity (92%), specificity (72%), positive predictive value (PPV) (71%) and negative predictive value (NPV) (93%) for diagnosing EBV-positive PTLD and followed patients' clinical course well (p < 0.001). Comparing the individual PCR assays, plasma EBNA PCR was superior with high sensitivity (77%), specificity (100%), PPV (100%) and NPV (86%). We conclude that EBV PCR is a useful test for managing PTLD patients. While plasma EBNA PCR is the best single assay for diagnosing and monitoring PTLD, the complete PCR panel is superior for ruling out its presence.

Idiopathic hypereosinophilic syndrome with skull base involvement.

Idiopathic hypereosinophilic syndrome (HES) is a heterogeneous disorder characterized by prolonged eosinophilia without an identifiable cause, ultimately resulting in organ dysfunction. Three major types of neurologic involvement have been well defined in HES; however, to our knowledge, inflammatory pseudotumor (IPT) in association with HES has not been reported. We present a case of IPT of the skull base in a patient with HES that suggests that HES may result in an exaggerated immunologic or inflammatory response leading to the formation of IPT.

Prognostic value of FDG-PET scan imaging in lymphoma patients undergoing autologous stem cell transplantation.

We conducted a retrospective analysis of 50 lymphoma patients (Hodgkin's disease and non-Hodgkin's lymphoma) who had an 18F-fluoro-deoxyglucose positron emission tomography (FDG-PET) scan after at least two cycles of salvage chemotherapy and before autologous stem cell transplantation (ASCT) at our institution. The patients were categorized into FDG-PET negative (N = 32) and positive (N = 18) groups. The median follow-up after ASCT was 19 months (range: 3-59). In the FDG-PET-negative group, the median progression-free survival (PFS) was 19 months (range: 2-59) with 15 (54%) patients without progression at 12 months after ASCT. The median overall survival (OS) for this group was not reached. In the FDG-PET-positive group, the median PFS was 5 months (range: 1-19) with only one (7%) patient without progression at 12 months after ASCT. The median OS was 19 months (range: 1-34). In the FDG-PET-negative group, chemotherapy-resistant patients by CT-based criteria had a comparable outcome to those with chemotherapy-sensitive disease. A positive FDG-PET scan after salvage chemotherapy and prior ASCT indicates an extremely poor chance of durable response after ASCT.

Treatment of PTLD with rituximab or chemotherapy.

Information regarding treatment of post-transplant lymphoproliferative disease (PTLD) beyond reduction in immunosuppression (RI) is limited. We retrospectively evaluated patients receiving rituximab and/or chemotherapy for PTLD for response, time to treatment failure (TTF) and overall survival (OS). Thirty-five patients met inclusion criteria. Twenty-two underwent rituximab treatment, with overall response rate (ORR) 68%. Median TTF was not reached at 19 months and estimated OS was 31 months. In univariable analysis, Epstein-Barr virus (EBV) positivity predicted response and TTF. LDH elevation predicted shorter OS. No patient died of rituximab toxicity and all patients who progressed underwent further treatment with chemotherapy. Twenty-three patients received chemotherapy. ORR was 74%, median TTF was 10.5 months and estimated OS was 42 months. Prognostic factors for response included stage, LDH and allograft involvement by tumor. These factors and lack of complete response (CR) predicted poor survival. Twenty-six percent of the patients receiving chemotherapy died of toxicity. Rituximab and chemotherapy are effective in patients with PTLD who fail or do not tolerate RI. While rituximab is well tolerated, toxicity of chemotherapy is marked. PTLD patients requiring therapy beyond RI should be considered for rituximab, especially with EBV-positive disease. Chemotherapy should be reserved for patients who fail rituximab, have EBV-negative tumors or need a rapid response.

Long-term event-free survivors after high-dose therapy and autologous stem-cell transplantation for low-grade follicular lymphoma.

Although follicular lymphoma (FL) is generally responsive to conventional-dose chemotherapy, improved survival in patients with this disease has been difficult to demonstrate. High-dose chemo/radiotherapy followed by autologous stem-cell transplantation (ASCT) can improve response rates, although its effects on survival remain controversial. Between 1990 and 2003, we transplanted 49 patients with low-grade FL at our institution. Twenty-two patients (45%) had undergone histologic transformation at the time of ASCT. In all, 44 patients (90%) had relapsed disease and five patients (10%) were resistant to chemotherapy at the time of transplantation. After ASCT, 30 patients (61%) were in complete remission (CR). The median overall survival (OS) has not been reached, while the median event-free survival (EFS) is 2.4 years. At a median follow-up of 5.5 years (longest 12.4 years), a plateau has been reached with 56% of patients remaining alive, and 35% event-free. ASCT was well tolerated except for two (4%) treatment-related deaths. In multivariable analysis, CR after ASCT and age less than 60 years are the best predictors of EFS and OS. ASCT is thus a safe therapeutic approach in FL, resulting in long-term EFS and OS for some patients, even with transformed disease.

Nonmyeloablative allogeneic stem cell transplantation for refractory Hodgkin's lymphoma complicated by interleukin-2 responsive progressive multifocal leukoencephalopathy.

Nonmyeloablative allogeneic stem cell transplantation (NMASCT) can be used to exploit the graft-versus-tumor (GVT) potential of allogeneic donor cells in the setting of reduced conditioning regimen toxicity. This approach is particularly attractive for patients who have received extensive prior therapy and are poor candidates for traditional allogeneic stem cell transplantation. However, toxicity in heavily pretreated patients remains uncertain. Additional immunosuppression in already immunocompromised patients may result in unexpected toxicity. We report a case of probable progressive multifocal leukoencephalopathy (PML) responsive to interleukin-2 (IL-2) following a NMASCT in a 29-year-old woman with relapsed Hodgkin's lymphoma. The patient developed severe neurological symptoms approximately 6 weeks following NMASCT associated with low CD4+ cell counts and magnetic resonance imaging (MRI) was consistent with PML. IL-2 therapy resulted in increasing CD4+ counts and progressive resolution of neurological symptoms. Disruption of IL-2 therapy led to neurological deterioration, which responded to reinstitution of IL-2 therapy. The patient's lymphoma initially progressed following NMASCT, but has responded to donor leukocyte infusions (DLI). This case reiterates the potent GVT potential of NMASCT in patients with Hodgkin's disease. However, it demonstrates the potential for severe complications related to immunosuppression, especially in heavily pretreated patients. The toxicity after NMASCT should not be understated and will need to be explored further.

Gemtuzumab ozogamicin (Mylotarg) monotherapy for relapsed AML after hematopoietic stem cell transplant: efficacy and incidence of hepatic veno-occlusive disease.

Gemtuzumab ozogamicin (GO) (Mylotarg, CMA-676) is a novel chemotherapeutic agent consisting of an anti-CD33 monoclonal antibody linked to calicheamicin, and is associated with a 30% response rate in patients with CD33-positive acute myeloid leukemia (AML) in first relapse. GO therapy has a 20% incidence of grade 3 or 4 hepatotoxicity, and has recently been associated with hepatic veno-occlusive disease (VOD). The efficacy and toxicity of GO in patients with AML who have relapsed after hematopoietic stem cell transplant (HSCT) is unknown, as this population was largely excluded from phase II studies. We reviewed the outcomes of eight consecutive patients with AML who received GO following relapse after HSCT. Two (25%) had responses to GO. One patient, who had had two previous HSCT and prior hyperbilirubinemia, developed severe VOD and died 14 days after GO therapy. The other seven patients did not meet diagnostic criteria for VOD. We conclude that GO can be safe and effective in patients who relapse following HSCT, but that caution is warranted in patients with multiple risk factors for VOD.

Staging and monitoring response to treatment in primary non-Hodgkin's lymphoma of bone marrow using (18)F-fluorodeoxyglucose positron emission tomography.

Bone marrow involvement can be found in patients with low-, intermediate-, or high-grade non-Hodgkin's lymphoma. A 40-year-old woman experienced onset of low back pain radiating into her entire right lower extremity. Plain x-rays of her right leg and computed tomography of chest, abdomen, and pelvis were unremarkable. Magnetic resonance imaging of pelvis and thighs revealed diffusely abnormal marrow signal (low T1 and high T2 weighted) in the pelvis and femora. The patient underwent (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan to evaluate the extent of her disease. The scan revealed diffuse scattered foci of abnormal FDG uptake in the bone/bone marrow, which was particularly intense in the axial bones. Bone marrow biopsy confirmed extensive involvement of the bone marrow with diffuse large B-cell lymphoma. This case report highlights the utility of FDG-PET in the detection of bone marrow involvement by aggressive lymphoma.