Evolving consolidation patterns and outcomes for a large cohort of primary CNS lymphoma patients.

Consolidation strategies for primary central nervous system lymphoma (PCNSL) after induction chemoimmunotherapy include whole-brain radiotherapy (≤24Gy reduced-dose [RD], >24Gy standard-dose [SD] WBRT) and cytarabine, non-myeloablative chemotherapy (NMC), or autologous hematopoietic cell transplantation (AHCT); however, comparative outcomes are lacking. PCNSL outcomes from 1983-2020 were stratified by decade and MSKCC recursive partitioning analysis (RPA) class. Clinicodemographic associations with consolidation were analyzed by multinomial logistic regression. Progression-free (PFS) and overall survival (OS) were analyzed by proportional hazards from consolidation. Of 559 patients, 385 (69%) were consolidated. Median follow-up and OS were 7.4 and 5.7 years, respectively. WBRT use declined (61% in 1990s vs. 12% in 2010s), while AHCT (4% in 1990s vs. 32% in 2010s) and NMC (27% in 1990s vs. 52% in 2010s) rose. Compared to RPA 1 (age<50), RPA 2 (age≥50, KPS≥70) was more likely to receive NMC. Those with partial response to induction were less likely to receive AHCT (OR 0.36, p=0.02). Among 351 with complete response to consolidation, only receipt of R-MPV induction was associated with improved PFS (HR 0.5, p=0.006). Among RPA 1, median PFS and OS were not reached for AHCT or RD-WBRT, vs. 2.5 and 13.0 years, respectively, after NMC. Among RPA class 3 (KPS<70), median PFS and OS post-RD-WBRT were 4.6 and 10 years, respectively, vs. 1.7 and 4.4 years post-NMC. No significant adjusted survival differences were seen across consolidation strategies. NMC is increasingly used in lieu of RD-WBRT despite a trend toward less favorable PFS. RD-WBRT can be considered in patients ineligible for AHCT.

A Phase II study assessing Long-Term Response to Ibrutinib Monotherapy in recurrent or refractory CNS Lymphoma.

BACKGROUND: Ibrutinib is a first-in-class inhibitor of Bruton tyrosine kinase (BTK). We previously reported the safety and short-term antitumor activity of ibrutinib in 20 patients with relapsed or refractory (r/r) primary (PCNSL) or secondary CNS lymphoma (SCNSL). PATIENTS AND METHODS: We enrolled 26 additional patients with r/r PCNSL/SCNSL into the dose-expansion cohort of the trial into a combined cohort of 46 patients (31 PCNSLs, 15 SCNSLs). Patients received ibrutinib at 560mg or 840mg daily in the dose-escalation and 840mg daily in the expansion cohort. Median follow up was 49.9 and 62.1 months for patients with PCNSL and SCNSL, respectively. We sequenced DNA from available tumor biopsies and cerebrospinal fluid (CSF) collected before and during ibrutinib therapy. RESULTS: Tumor responses were observed in 23/31 (74%) PCNSLs and 9/15 (60%) SCNSLs, including 12 complete responses in PCNSL and 7 in SCNSL. Median progression-free survival (PFS) for PCNSL was 4.5 months (95%CI: 2.8-9.2) with 1y-PFS at 23.7% (95%CI: 12.4%-45.1%). Median duration of response (DOR) in the 23 PCNSL responders was 5.5 months. Median PFS in SCNSL was 5.3 months (95%CI: 1.3-14.5) with a median DOR 8.7 months for the 9 responders. Exploratory biomarker analysis suggests that mutations in TBL1XR1 may be associated with a long-term response to ibrutinib in PCNSL (p=0.0075). Clearance of circulating tumor DNA from CSF was associated with complete and long-term ibrutinib response. CONCLUSIONS: Our study confirms single-agent activity of ibrutinib in r/r CNS lymphoma and identifies molecular determinants of response based on long-term follow up. CLINICAL TRIAL INFORMATION: NCT02315326.

Low-Dose Planned Glucarpidase Allows Safe Outpatient High-Dose Methotrexate Treatment for CNS Lymphoma.

PURPOSE: High-dose methotrexate (HD-MTX) is the backbone of curative therapy for CNS lymphoma. Because of toxicity, MTX is administered in the inpatient setting along with hyperhydration and monitoring until MTX clearance is documented (3-5 days). Frequent hospitalizations result in patient time away from work, home, and exposure to potential iatrogenic/nosocomial complications. Here, we aim to demonstrate feasibility of HD-MTX administration in the outpatient setting with low-dose glucarpidase facilitating clearance. METHODS: This is a prospective nonrandomized study of outpatient HD-MTX followed by glucarpidase 2000u (ClinicalTrials.gov identifier: NCT03684980). Eligible patients had CNS lymphoma, creatinine <1.3 mg/dL, and previously tolerated HD-MTX. Patients were enrolled between May 2020 December 2021 for one HD-MTX treatment. Patients could re-enroll for subsequent doses of HD-MTX as eligibility and slots permitted. MTX 3.5 g/m2 was administered once over 2 hours, preceded by standard hydration and followed by an additional 2 hours of dextrose 5% in water with NaHCO3 75 mEq at 150 cc/h. Glucarpidase 2000u was administered once in the clinic 24 hours later. The primary end point was MTX level 48 hours after HD-MTX. RESULTS: Twenty doses of outpatient HD-MTX with glucarpidase were administered to seven patients. After 20 of 20 (100%) treatments, serum MTX levels were reduced to <100 nmol/L. Treatments were well-tolerated, and no admissions were required. One patient received additional outpatient hydration for elevated creatinine. Development of antiglucarpidase antibody was rare and did not affect treatment. CONCLUSION: Outpatient HD-MTX with glucarpidase is safe and well-tolerated and has the potential to alter standard treatment for CNS lymphoma.

CNS Bridging Radiotherapy Achieves Rapid Cytoreduction Prior to CAR T Cell Therapy for Aggressive B-Cell Lymphoma.

CAR T-cell therapy (CAR T) for central nervous system lymphoma (CNSL) is a promising strategy, yet responses are frequently not durable. Bridging radiotherapy (BRT) is used for extra-cranial lymphoma where it can improve CAR T outcomes through cytoreduction of high-risk lesions. We hypothesized that BRT would achieve similar, significant cytoreduction prior to CAR T for CNSL (CNS-BRT). We identified CNSL patients with non-Hodgkin B-cell lymphoma who received CNS-BRT prior to commercial CAR T. Cytoreduction from CNS-BRT was calculated as change in lesion size prior to CAR T. Twelve patients received CNS-BRT, and the median follow up among survivors is 11.8 months (IQR: 8.5 - 21.9). Ten patients had CNSL (9 secondary, 1 primary) and 2 patients had epidural disease (evaluable for toxicity). All ten patients with CNSL had progressive disease at the time of CNS-BRT. 1/12 patients experienced grade ≥ 3 cytokine release syndrome (CRS), and 3/12 patients experienced grade ≥ 3 immune effector cell-associated neurotoxicity syndrome (ICANS). CNS-BRT achieved a 74.0% (95% confidence interval: 62.0 - 86.0) mean reduction in lesion size from baseline (p = 0.014) at a median of 12 days from BRT completion and prior to CAR T infusion. Best CNS response included 8 complete responses (CR), 1 partial response (PR), and 1 progressive disease (PD). Three patients experienced CNS relapse outside the BRT field. Preliminary data suggest CNS-BRT achieves rapid cytoreduction and is associated with a favorable CNS response and safety profile. These data support further study of BRT as a bridging modality for CNSL CAR T.

Targets and treatments in primary CNS lymphoma.

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive lymphoma entirely localized in the central nervous system or vitreoretinal space. PCNSL generally initially responds to methotrexate-containing chemotherapy regimens, but progressive or relapsing disease is common, and the prognosis is poor for relapsed or refractory (R/R) patients. PCNSL is often characterized by activation of nuclear factor kappa B (NF-κB) due to mutations in the B-cell receptor (BCR) or toll-like receptor (TLR) pathways, as well as immune evasion. Targeted treatments that inhibit key PCNSL mechanisms and pathways are being evaluated; inhibition of Bruton's tyrosine kinase (BTK) downstream of BCR activation has demonstrated promising results in treating R/R disease. This review will summarize the evidence and potential for targeted therapeutic agents to improve treatment outcomes in PCNSL. This includes immunotherapeutic and immunomodulatory approaches and inhibitors of the key pathways driving PCNSL, such as aberrant BCR and TLR signaling.

Bruton's tyrosine kinase (BTK) inhibitors for the treatment of primary central nervous system lymphoma (PCNSL): current progress and latest advances.

The incidence of primary central nervous system lymphoma (PCNSL) has steadily increased, particularly in elderly patients. Although highly responsive to first-line chemotherapy and radiotherapy, approximately 50% of patients relapse or become refractory within 1 year. Prognosis following relapse is dismal and no standard salvage therapy exists. Bruton's tyrosine kinase (BTK), a key regulator of the B-cell receptor (BCR) pathway, has emerged as a promising therapeutic target. The first BTK inhibitor ibrutinib has been evaluated in the relapsed/refractory PCNSL setting, with overall response rates of 51.9%-89.0% and median progression-free survival of 4.6-4.8 months. However, ibrutinib inhibits several kinases in addition to BTK, leading to off-target effects. Second-generation BTK inhibitors have since been developed, which afford greater selectivity for BTK and fewer off-target effects. We review current practices in the diagnosis and evaluation of PCNSL, as well as clinical trials of BTK inhibitors in PCNSL and future developments in PCNSL treatment.

Liquid biopsy for improving diagnosis and monitoring of CNS lymphomas: A RANO review.

BACKGROUND: The utility of liquid biopsies is well documented in several extracranial and intracranial (brain/leptomeningeal metastases, gliomas) tumors. METHODS: The RANO (Response Assessment in Neuro-Oncology) group has set up a multidisciplinary Task Force to critically review the role of blood and cerebrospinal fluid (CSF)-liquid biopsy in CNS lymphomas, with a main focus on primary central nervous system lymphomas (PCNSL). RESULTS: Several clinical applications are suggested: diagnosis of PCNSL in critical settings (elderly or frail patients, deep locations, and steroid responsiveness), definition of minimal residual disease, early indication of tumor response or relapse following treatments, and prediction of outcome. CONCLUSIONS: Thus far, no clinically validated circulating biomarkers for managing both primary and secondary CNS lymphomas exist. There is need of standardization of biofluid collection, choice of analytes, and type of technique to perform the molecular analysis. The various assays should be evaluated through well-organized central testing within clinical trials.

Primary central nervous system lymphoma.

Primary central nervous system lymphoma (PCNSL) is a diffuse large B cell lymphoma in which the brain, spinal cord, leptomeninges and/or eyes are exclusive sites of disease. Pathophysiology is incompletely understood, although a central role seems to comprise immunoglobulins binding to self-proteins expressed in the central nervous system (CNS) and alterations of genes involved in B cell receptor, Toll-like receptor and NF-κB signalling. Other factors such as T cells, macrophages or microglia, endothelial cells, chemokines, and interleukins, probably also have important roles. Clinical presentation varies depending on the involved regions of the CNS. Standard of care includes methotrexate-based polychemotherapy followed by age-tailored thiotepa-based conditioned autologous stem cell transplantation and, in patients unsuitable for such treatment, consolidation with whole-brain radiotherapy or single-drug maintenance. Personalized treatment, primary radiotherapy and only supportive care should be considered in unfit, frail patients. Despite available treatments, 15-25% of patients do not respond to chemotherapy and 25-50% relapse after initial response. Relapse rates are higher in older patients, although the prognosis of patients experiencing relapse is poor independent of age. Further research is needed to identify diagnostic biomarkers, treatments with higher efficacy and less neurotoxicity, strategies to improve the penetration of drugs into the CNS, and roles of other therapies such as immunotherapies and adoptive cell therapies.

Long-term Outcomes in Primary CNS Lymphoma After R-MVP and High-Dose Chemotherapy With Autologous Hematopoietic Stem Cell Transplant.

BACKGROUND AND OBJECTIVES: Primary CNS lymphoma (PCNSL), a rare CNS malignancy, is usually treated with high-dose methotrexate in the first-line setting, typically followed by consolidation therapy. Due to the broad range of currently available treatments for PCNSL, comparability in long-term follow-up studies is limited, and data are scattered across small studies. METHODS: In this study, we report the long-term survival of patients with newly diagnosed immunocompetent PCNSL, enrolled in a phase II trial from June 2005 to September 2011. Patients were treated using rituximab, methotrexate, vincristine, and procarbazine (R-MVP) chemotherapy followed by high-dose chemotherapy (HDC) and autologous stem cell transplant (ASCT) in those with partial or complete response to R-MVP. In a post hoc analysis, clinical and imaging features were evaluated in those still alive. RESULTS: 26 of 32 patients underwent HDC-ASCT consolidation. Of them, 3 patients died of treatment-related toxicity and 2 due to disease progression within 1 year of ASCT. None of the remaining 21 patients had disease progression with a median follow-up of 12.1 years and were included in the analysis. Compared with the post-HDC-ASCT assessment, at the last follow-up, there was no significant difference in the median Karnofsky Performance Status (80 [range: 60-100] vs 90 [range: 70-100]), the median Neurologic Assessment in Neuro-Oncology score (1 [range: 0-4] vs 1 [range: 0-5]), and leukoencephalopathy score (1 [range: 0-3] vs 1 [range: 1-4]). DISCUSSION: Long-term follow-up demonstrated that treatment was well tolerated in most patients enrolled in this study, with stable leukoencephalopathy on imaging and stable clinical performance status. Disease recurrence was not observed beyond 2 years after HDC-ASCT consolidation.

Preclinical and clinical evaluation of Buparlisib (BKM120) in recurrent/refractory Central Nervous System Lymphoma.

Central Nervous System (CNS) Lymphomas are aggressive brain tumors with limited treatment options. Targeting the phosphoinositide 3-kinase (PI3K) pathway yields promising responses across B-cell malignancies, but its therapeutic potential in CNS lymphomas remains unexplored. We present pre-clinical and clinical data on the pan-PI3K inhibitor Buparlisib in CNS lymphomas. In a primary CNS lymphoma-patient-derived cell line, we define the EC50. Four patients with recurrent CNS lymphoma were enrolled in a prospective trial. We evaluated Buparlisib plasma and cerebrospinal fluid pharmacokinetics, clinical outcomes, and adverse events. Treatment was well tolerated. Common toxicities include hyperglycemia, thrombocytopenia, and lymphopenia. The presence of Buparlisib in plasma and CSF was confirmed 2h post-treatment with a median CSF concentration below the EC50 defined in the cell line All four patients were evaluated for response and the median time to progression was 39 days. Buparlisib monotherapy did not lead to meaningful responses and the trial was prematurely stopped.Clinical Trial Registration: NCT02301364.

Is more better? Increased doses of high dose methotrexate and addition of rituximab is associated with improved outcomes in a large primary CNS lymphoma cohort.

Background: Primary central nervous system lymphoma (PCNSL) is a rare and aggressive primary brain tumor. While high dose methotrexate (HDMTX) regimens remain standard of care, it remains unclear if optimization of HDMTX doses and the addition of rituximab provide clinical benefit. Over the last 30 years, standard care given at Memorial Sloan Kettering Cancer Center (MSKCC) has evolved, allowing the comparison of patients receiving different numbers of HDMTX doses and those treated with and without rituximab. The purpose of this study was to describe outcomes based on treatment pattern changes. Methods: This single-center, retrospective, IRB-approved study at MSKCC included patients with immunocompetent PCNSL, age ≥18 years and diagnosed between 1/1983-12/2017. Overall survival (OS) was modeled from date of last HDMTX for analyses associating HDMTX and OS. Multivariable Cox regression models estimated hazard ratios (HR) and corresponding 95% confidence intervals (CI). Results: There were 546 patients identified with newly diagnosed PCNSL. Median overall survival (mOS) of the entire population was 4.7 years (95% CI: 3.8-5.7 years); 3.3 years (95% CI: 2.7-3.9 years) in patients diagnosed prior to 2006 and 8.1 years (95% CI: 6.6-11.1 years) in patients diagnosed 2006 onwards. Patients receiving ≥6 doses of HDMTX had improved survival compared to those receiving <6 doses of HDMTX (mOS: 7.8 vs. 4.3 years; P=0.001). Patients receiving induction rituximab had improved OS compared to those who did not receive rituximab (mOS: 10.5 vs. 3.2 years; P<0.0001). Patients receiving ≥6 doses of HDMTX and rituximab had greatest mOS at 13 years, with a 70% reduction in death (HR =0.30; 95% CI: 0.19-0.47) adjusting for treatment era, sex, and recursive partitioning analysis (RPA) classes comprising age and karnofsky performance score (KPS). Conclusions: OS for PCNSL has improved significantly over the last few decades. Patients seem to benefit with ≥6 doses of HDMTX and the addition of rituximab, an effect independent of treatment era, age, and KPS.

Combination Olaparib and Temozolomide for the Treatment of Glioma: A Retrospective Case Series.

OBJECTIVES: To report on the tolerability and efficacy of olaparib with temozolomide (TMZ) for glioma METHODS: Single-center retrospective series of glioma patients treated with olaparib/TMZ September 2018-December 2021 RESULTS: Twenty patients (median age: 42, median Karnofsky Performance Status: 90) received olaparib/TMZ for diagnoses of IDH-mutant oligodendroglioma (n=5), IDH-mutant astrocytoma grade 2-3 (n=4), IDH-mutant astrocytoma grade 4 (n=7), or IDH-wildtype glioma (n=4). One patient was treated upfront and 19 at recurrence (median=3). Olaparib 150mg was administered three times/week concurrent with TMZ 50-75mg/m2 daily. Fatigue, gastrointestinal symptoms, and hematologic toxicity were common. 6/20 patients required dose reduction (n=4) or discontinuation (n=2) due to toxicity. Radiographic response was evaluable in 16 and observed (complete + partial) in 4/8 with IDH-mutant grade 2-3 glioma. No responses were seen in patients with grade 4 IDH-mutant astrocytomas (0/5) or IDH-wildtype gliomas (0/3). Progression-free survival was 7.8, 1.3, and 2.0 months, respectively. DISCUSSION: Olaparib/TMZ resulted in objective radiographic response in 50% of evaluable patients with recurrent IDH-mutant grade 2-3 gliomas with encouraging PFS and manageable toxicity. This supports a prospective trial of olaparib/TMZ for this population. CLASSIFICATION OF EVIDENCE: This case series provides Class IV evidence that treatment with olaparib/TMZ may result in radiographic response in patients with glioma.

Impact of severe acute respiratory syndrome coronavirus-2 infection on the outcome of primary central nervous system lymphoma treatment: A study of the International PCNSL Collaborative Group.

To optimise management of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection identifying high-risk patients and maintaining treatment dose intensity is an important issue in patients with aggressive lymphomas. In the present study, we report on the presentation, management, and outcome of an international series of 91 patients with primary central nervous system lymphoma and SARS-CoV-2 infection. SARS-CoV-2 was diagnosed before/during first-line treatment in 64 patients, during follow-up in 21, and during salvage therapy in six. Among the 64 patients infected before/during first-line chemotherapy, 38 (59%) developed pneumonia and 26 (41%) did not clear the virus. Prolonged exposure to steroids before viral infection and/or treatment with high-dose cytarabine favoured pneumonia development and virus persistence and were associated with poorer survival; 81% of patients who did not clear virus died early from coronavirus disease 2019 (COVID-19). Vaccination was associated with lower pneumonia incidence and in-hospital mortality. Chemotherapy was initiated/resumed in 43 (67%) patients, more commonly among patients who did not develop pneumonia, cleared the virus, or did not receive steroids during infection. Chemotherapy resumption in patients with viral persistence should be indicated cautiously as it was associated with a poorer survival (6-month, 70% and 87%, p = 0.07). None of the 21 patients infected during follow-up died from COVID-19, requiring similar measures as infected subjects in the general population.

Routine use of low-dose glucarpidase following high-dose methotrexate in adult patients with CNS lymphoma: an open-label, multi-center phase I study.

BACKGROUND: High-dose methotrexate (HD-MTX) has broad use in the treatment of central nervous system (CNS) malignancies but confers significant toxicity without inpatient hydration and monitoring. Glucarpidase is a bacterial recombinant enzyme dosed at 50 units (u)/kg, resulting in rapid systemic MTX clearance. The aim of this study was to demonstrate feasibility of low-dose glucarpidase to facilitate MTX clearance in patients with CNS lymphoma (CNSL). METHODS: Eight CNSL patients received HD-MTX 3 or 6 g/m2 and glucarpidase 2000 or 1000u 24 h later. Treatments repeated every 2 weeks up to 8 cycles. RESULTS: Fifty-five treatments were administered. Glucarpidase 2000u yielded > 95% reduction in plasma MTX within 15 min following 33/34 doses (97.1%) and glucarpidase 1000u yielded > 95% reduction following 15/20 doses (75%). Anti-glucarpidase antibodies developed in 4 patients and were associated with MTX rebound. In CSF, glucarpidase was not detected and MTX levels remained cytotoxic after 1 (3299.5 nmol/L, n = 8) and 6 h (1254.7 nmol/L, n = 7). Treatment was safe and well-tolerated. Radiographic responses in 6 of 8 patients (75%) were as expected following MTX-based therapy. CONCLUSIONS: This study demonstrates feasibility of planned-use low-dose glucarpidase for MTX clearance and supports the hypothesis that glucarpidase does not impact MTX efficacy in the CNS. CLINICAL TRIAL REGISTRATION: NCT03684980 (Registration date 26/09/2018).

Unilateral panuveitis secondary to JAK2 mutation-associated lymphoproliferative disease.

A woman in her 70s experienced painless vision loss in the right eye for 1 month. Acute retinal necrosis-induced panuveitis was the referral diagnosis. With dense vitreous haze, a vitrectomy was performed for vitreous biopsy followed by multimodal imaging. Vitreous biopsy yielded negative PCR results for herpes viruses and only inflammatory cells. Post-vitrectomy imaging showed involuted but pervasive pigmentary foci in the outer retina and the retinal pigment epithelium. Concurrently, peripheral blood showed pancytosis with giant platelets and a Janus kinase 2 (JAK2) mutation, which prompted a haematological evaluation. CT and MRI revealed a right frontal lobe intra-axial mass, diagnosed as diffuse large B cell lymphoma (DLBCL). Subsequently, bone marrow aspirate confirmed the pathogenic V617F JAK2 mutation. Following chemotherapy, the patient achieved lymphoma regression and uveitic quiescence. This is the first case report of acute unilateral panuveitis in a patient with JAK2 mutation and DLBCL but without evidence of intraocular involvement.