Report of an international workshop to standardize baseline evaluation and response criteria for primary CNS lymphoma

CAR T-cell therapy induces a high rate of prolonged remission in relapsed primary CNS lymphoma: Real-life results of the LOC network

The prognosis of relapsed primary central nervous system lymphoma (PCNSL) remains dismal. CAR T-cells are a major contributor to systemic lymphomas, but their use in PCNSL is limited. From the LOC network database, we retrospectively selected PCNSL who had leukapheresis for CAR-T cells from the third line of treatment, and, as controls, PCNSL treated with any treatment, at least in the third line and considered not eligible for ASCT. Twenty-seven patients (median age: 68, median of three previous lines, including ASCT in 14/27) had leukapheresis, of whom 25 received CAR T-cells (tisa-cel: N = 16, axi-cel: N = 9) between 2020 and 2023. All but one received a bridging therapy. The median follow-up after leukapheresis was 20.8 months. The best response after CAR-T cells was complete response in 16 patients (64%). One-year progression-free survival from leukapheresis was 43% with a plateau afterward. One-year relapse-free survival was 79% for patients in complete or partial response at CAR T-cell infusion. The median overall survival was 21.2 months. Twenty-three patients experienced a cytokine release syndrome and 17/25 patients (68%) a neurotoxicity (five grade ≥3). The efficacy endpoints were significantly better in the CAR T-cell group than in the control group (N = 247) (median PFS: 3 months; median OS: 4.7 months; p < 0.001). This series represents the largest cohort of PCNSL treated with CAR T-cells reported worldwide. CAR T-cells are effective in relapsed PCNSL, with a high rate of long-term remission and a reassuring tolerance profile. The results seem clearly superior to those usually observed in this setting.

Pre-treatment systemic inflammation response index and systemic immune inflammation in patients with primary central nerve system lymphoma as a useful prognostic indicator

PURPOSE

The systemic inflammation response index (SIRI) and systemic immune-inflammation index (SII) are based on neutrophil, monocyte, platelet, and lymphocyte counts. The SIRI and SII are used to predict the survival of patients with malignant tumors. It is well known that the inflammatory immune response is closely related to cancer occurrence and progression. In the present study, we evaluated the potential prognostic significance of SIRI and SII in patients with primary central nervous system lymphoma (PCNSL).

METHODS

Fifty-eight consecutive patients were enrolled in this study between November 2006 and May 2022. Among the 58 patients, 47 patients with sufficient blood test data and follow-up were analyzed. The patients with steroid intake at the time point of the blood test and higher C-reactive protein were excluded.

RESULTS

The median follow-up and survival times were 31 and 36 months, respectively. The optimal cutoff SIRI value was based on the receiver operating characteristic curve (ROC) for overall survival (OS) and stratified patients into low (< 1.43 × 109/L, n = 22) and high (≥ 1.43 × 109/L, n = 25) SIRI groups. The optimal cutoff SII value based on the ROC for OS stratified patients into low (< 694.9, n = 28) and high (≥ 694.9, n = 19) SII groups. A low SIRI value was associated with longer OS (p = 0.006). Furthermore, a low SII value was associated with longer OS (p = 0.044). The prognostic factors associated with prolonged survival in univariate analysis using the Cox proportional hazard model were age < 65 years, low SIRI, and low SII. The multivariate analysis demonstrated that age < 65 years and low SIRI independently predicted longer OS.

CONCLUSION

Simple, less expensive, and routinely ordered preoperative blood count assessments such as SIRI and SII predict the OS of patients with PCNSL. This study demonstrated that PCNSL is associated with pre-treatment systemic immune-inflammation states.

Myeloablative vs nonmyeloablative consolidation for primary central nervous system lymphoma: results of Alliance 51101

ABSTRACT

Although it is evident that standard-dose whole-brain radiotherapy as consolidation is associated with significant neurotoxicity, the optimal consolidative strategy for primary central nervous system lymphoma (PCNSL) is not defined. We performed a randomized phase 2 clinical trial via the US Alliance cancer cooperative group to compare myeloablative consolidation supported by autologous stem cell transplantation with nonmyeloablative consolidation after induction therapy for PCNSL. To our knowledge, this is the first randomized trial to be initiated that eliminates whole-brain radiotherapy as a consolidative approach in newly diagnosed PCNSL. Patients aged 18 to 75 years were randomly assigned in a 1:1 manner to induction therapy (methotrexate, temozolomide, rituximab, and cytarabine) followed by consolidation with either thiotepa plus carmustine and autologous stem cell rescue vs induction followed by nonmyeloablative, infusional etoposide plus cytarabine. The primary end point was progression-free survival (PFS). A total of 113 patients were randomized, and 108 (54 in each arm) were evaluable. More patients in the nonmyeloablative arm experienced progressive disease or death during induction (28% vs 11%; P = .05). Thirty-six patients received autologous stem cell transplant, and 34 received nonmyeloablative consolidation. The estimated 2-year PFS was higher in the myeloablative vs nonmyeloablative arm (73% vs 51%; P = .02). However, a planned secondary analysis, landmarked at start of the consolidation, revealed that the estimated 2-year PFS in those who completed consolidation therapy was not significantly different between the arms (86% vs 71%; P = .21). Both consolidative strategies yielded encouraging efficacy and similar toxicity profiles. This trial was registered at www.clininicals.gov as #NCT01511562.

Prognostic Value of CSF IL-10 at Early Assessment of Induction Chemotherapy in Primary CNS Lymphomas: A LOC Network Study

OBJECTIVES

Despite a high response rate at the first evaluation during induction chemotherapy, the risk of early relapse remains high and unpredictable in primary CNS lymphomas (PCSNLs). We aimed to assess the prognostic value of early IL-10 levels in CSF (e-IL-10) after 2 months of induction chemotherapy.

METHODS

We retrospectively selected from the LOC (Lymphomes Oculo-Cérébraux) network database patients with PCSNLs who had complete or partial response at the 2-month evaluation of a high-dose methotrexate-based first-line chemotherapy for whom e-IL-10 was available.

RESULTS

Thirty patients (median age: 62 years, brain involvement in 30/30, CSF involvement in 10/30, median baseline CSF IL-10: 27.5 pg/mL) met the selection criteria. e-IL-10 was undetectable in 22 patients and detectable in 8 patients. At the end of induction treatment, 7 of 8 and 4 of 22 of the patients with detectable and undetectable e-IL-10 had experienced progressive disease, respectively (p = 0.001, OR: 26.8, 95% CI 2-1,478). The median progression-free survival times were 5.8 months (95% CI 2.8-8.8) and 28.7 months (95% CI 13.4-43.9) in the groups with detectable and undetectable e-IL-10, respectively (p < 0.001).

DISCUSSION

Our results suggest that despite an objective response, the persistence of detectable e-IL-10 is associated with a high risk of early relapse in PCNSL. A closer follow-up of such patients is warranted.

Primary central nervous system lymphomas in immunocompromised patients require specific response criteria

PURPOSE

Immunosuppression is a well-established risk factor for primary central nervous system lymphomas (PCNSLs), which present in this context distinct radiological characteristics. Our aim was to describe the radiological evolution of treated PCNSL in immunocompromised patients and suggest adapted MRI response criteria.

METHODS

We conducted a multicenter retrospective study of patients from the French LOC, K-Virogref and CANCERVIH network databases and enrolled adult immunocompromised patients with newly diagnosed PCNSL.

RESULTS

We evaluated the baseline, intermediate, end-of-treatment and follow-up MRI data of 31 patients (9 living with HIV, 16 with solid organ transplantation and 6 with an autoimmune disease under chronic immunosuppressive therapy). At baseline, 23/30 (77%) patients had necrotic lesions with ring enhancement and 28% of the lesions were hemorrhagic. At the end of the first-line treatment, 12/28 (43%) patients could not be classified according to the IPCG criteria. Thirteen of 28 (46%) patients still harbored contrast enhancement, and 11/28 (39%) patients had persistent large necrotic lesions with a median diameter of 15 mm. These aspects were not associated with a pejorative outcome and progressively diminished during follow-up. Six patients relapsed; however, we failed to identify any neuroimaging risk factors on the end-of-treatment MRI.

CONCLUSION

In immunocompromised patients, PCNSLs often harbor alarming features on end-of-treatment MRI, with persistent contrast-enhanced lesions frequently observed. However, these aspects seemed to be related to the necrotic and hemorrhagic nature of the lesions and were not predictive of a pejorative outcome. Specific response criteria for this population are thereby proposed.

Diagnostics and treatment delay in primary central nervous system lymphoma: What the neurosurgeon should know

PURPOSE

The gold standard for diagnostics in primary central nervous system lymphoma (PCNSL) is histopathological diagnosis after stereotactic biopsy. Yet, PCNSL has a multidisciplinary diagnostic work up, which associated with diagnostic delay and could result in treatment delay. This article offers recommendations to neurosurgeons involved in clinical decision-making regarding (novel) diagnostics and care for patients with PCNSL with the aim to improve uniformity and timeliness of the diagnostic process for patients with PCNSL.

METHODS

We present a mini review to discuss the role of stereotactic biopsy in the context of novel developments in diagnostics for PCNSL, as well as the role for cytoreductive surgery.

RESULTS

Cerebrospinal fluid-based diagnostics are supplementary and cannot replace stereotactic biopsy-based diagnostics.

CONCLUSION

Histopathological diagnosis after stereotactic biopsy of the brain remains the gold standard for diagnosis. Additional diagnostics should not be a cause of diagnostic delay. There is currently no sufficient evidence supporting cytoreductive surgery in PCNSL, with recent studies showing contradictive data and suboptimal study designs.

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.

Clinical outcomes of etoposide and cytarabine as consolidation in elderly patients with primary CNS lymphoma

BACKGROUND

A consolidation strategy has not been established for transplant-ineligible elderly patients with primary central nervous system lymphoma (PCNSL). In this study, we aimed to retrospectively evaluate the clinical outcomes of etoposide and cytarabine (EA) as consolidation chemotherapy for transplant-ineligible patients with PCNSL following high-dose methotrexate (MTX)-based induction chemotherapy.

MATERIALS AND METHODS

Between 2015 and 2021, newly diagnosed transplant-ineligible patients with PCNSL with diffuse large B-cell lymphoma were consecutively enrolled. All enrolled patients were over 60 years old and received EA consolidation after achieving a complete or partial response following induction chemotherapy.

RESULTS

Of the 85 patients who achieved a complete or partial response to MTX-based induction chemotherapy, 51 received EA consolidation chemotherapy. Among the 25 (49.0%, 25/51) patients in partial remission before EA consolidation, 56% (n = 14) achieved complete remission after EA consolidation. The median overall survival and progression-free survival were 43 and 13 months, respectively. Hematological toxicities were most common, and all patients experienced grade 4 neutropenia and thrombocytopenia. Forty-eight patients experienced febrile neutropenia during consolidation chemotherapy, and 4 patients died owing to treatment-related complications.

CONCLUSION

EA consolidation chemotherapy for transplant-ineligible, elderly patients with PCNSL improved response rates but showed a high relapse rate and short progression-free survival. The incidences of treatment-related mortality caused by hematologic toxicities and severe infections were very high, even after dose modification. Therefore, the use of EA consolidation should be reconsidered in elderly patients with PCNSL.

Primary central nervous system lymphomas: EHA-ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up

This EHA-ESMO Clinical Practice Guideline provides key recommendations for managing primary DLBCL of the CNS.The guideline covers clinical, imaging and pathological diagnosis, staging and risk assessment, treatment and follow-up.Algorithms for first-line and salvage treatments are provided.The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe.Recommendations are based on available scientific data and the authors' collective expert opinion.

Machine learning-based pathomics signature of histology slides as a novel prognostic indicator in primary central nervous system lymphoma

PURPOSE

To develop and validate a pathomics signature for predicting the outcomes of Primary Central Nervous System Lymphoma (PCNSL).

METHODS

In this study, 132 whole-slide images (WSIs) of 114 patients with PCNSL were enrolled. Quantitative features of hematoxylin and eosin (H&E) stained slides were extracted using CellProfiler. A pathomics signature was established and validated. Cox regression analysis, receiver operating characteristic (ROC) curves, Calibration, decision curve analysis (DCA), and net reclassification improvement (NRI) were performed to assess the significance and performance.

RESULTS

In total, 802 features were extracted using a fully automated pipeline. Six machine-learning classifiers demonstrated high accuracy in distinguishing malignant neoplasms. The pathomics signature remained a significant factor of overall survival (OS) and progression-free survival (PFS) in the training cohort (OS: HR 7.423, p < 0.001; PFS: HR 2.143, p = 0.022) and independent validation cohort (OS: HR 4.204, p = 0.017; PFS: HR 3.243, p = 0.005). A significantly lower response rate to initial treatment was found in high Path-score group (19/35, 54.29%) as compared to patients in the low Path-score group (16/70, 22.86%; p < 0.001). The DCA and NRI analyses confirmed that the nomogram showed incremental performance compared with existing models. The ROC curve demonstrated a relatively sensitive and specific profile for the nomogram (1-, 2-, and 3-year AUC = 0.862, 0.932, and 0.927, respectively).

CONCLUSION

As a novel, non-invasive, and convenient approach, the newly developed pathomics signature is a powerful predictor of OS and PFS in PCNSL and might be a potential predictive indicator for therapeutic response.

Clinical characteristics and prognosis of patients with newly diagnosed primary central nervous system lymphoma: a multicentre retrospective analysis

Bruton's tyrosine kinase inhibitors (BTKi) exhibit superior efficacy in relapsed/refractory primary central nervous system lymphoma (PCNSL), but few studies have evaluated patients with newly diagnosed PCNSL, and even fewer studies have evaluated differences in efficacy between treatment with BTKi and traditional chemotherapy. This study retrospectively analyzed the clinical characteristics of 86 patients with PCNSL and identified predictors of poor prognosis for overall survival (OS). After excluding patients who only received palliative care, 82 patients were evaluated for efficacy and survival. According to the induction regimen, patients were divided into the traditional chemotherapy, BTKi combination therapy, and radiotherapy groups; the objective response rates (ORR) of the three groups were 71.4%, 96.2%, and 71.4% (P = 0.037), respectively. Both median progression-free survival and median duration of remission showed statistically significant differences (P = 0.019 and P = 0.030, respectively). The median OS of the BTKi-containing therapy group was also longer than that of the traditional chemotherapy group (not reached versus 47.8 (32.5-63.1) months, P = 0.038).Seventy-one patients who achieved an ORR were further analyzed, and achieved an ORR after four cycles of treatment and maintenance therapy had prolonged OS (P = 0.003 and P = 0.043, respectively). In conclusion, survival, and prognosis of patients with newly diagnosed PCNSL are influenced by the treatment regimen, with the BTKi-containing regimen showing great potential.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare type of non-Hodgkin lymphoma (NHL) manifesting in the brain, spinal cord, cerebrospinal fluid and/or eyes, in the absence of systemic manifestations. With an increasing incidence and a 30% 5-year overall survival if promptly treated, timely diagnosis and subsequent treatment is paramount. The typical MRI appearance for PCNSL is a solitary or multiple T2-hypointense, homogeneous gadolinium-enhancing lesion with restricted diffusion. Dexamethasone treatment might compromise and delay the diagnosis. Hallmark of treatment is induction with intravenous high-dose methotrexate consisting polychemotherapy followed by consolidation treatment. Consolidation treatment consists of either whole brain radiotherapy (WBRT) or autologous stem cell transplantation (ASCT). Given the (cognitive) side effects of WBRT, ASCT is increasingly being used as the first choice of treatment.

Diffuse large B-cell lymphoma with contemporary involvement of central and peripheral nervous system: A case report and literature review

Introduction

Simultaneous involvement of the peripheral nervous system (PNS) and central nervous system (CNS) during the same period in diffuse large B-cell lymphoma (DLBCL) is rarely documented. In this particular case, the diagnosis of diffuse large B-cell lymphoma was pathologically confirmed, with invasion into the basal ganglia, diencephalon, and several peripheral nerves. The initial clinical manifestations were dyspnoea and hyperventilation.

Case presentation

The patient presented to the hospital with fatigue, dyspnoea, and limb pain for over 7 months, accompanied by progressive breathlessness and unconsciousness in the last 6 days. Initial treatment with glucocorticoids for Guillain-Barre syndrome (GBS) proved ineffective in controlling the severe shortness of breath and hyperventilation, necessitating the use of ventilator-assisted ventilation. 18-Fluorodeoxyglucose positron emission tomography/computed tomography (18FDG PET/CT) showed that the basal ganglia, brainstem, and multiple peripheral nerves were thickened and metabolically active. There were atypical cells in the cerebrospinal fluid; the pathology indicated invasive B-cell lymphoma, demonstrating a propensity toward diffuse large B-cell lymphoma (DLBCL). After receiving chemotherapy, the patient regained consciousness and was successfully weaned off ventilator assistance but died of severe pneumonia.

Discussion

The early clinical manifestations of DLBCL lack specificity, and multifocal DLBCL complicates the diagnostic process. When a single primary disease cannot explain multiple symptoms, the possibility of DLBCL should be considered, and nervous system invasion should be considered when nervous system symptoms are present. Once nervous system involvement occurs in DLBCL, whether the central or peripheral nervous system, it indicates a poor prognosis.

Survival, neurocognitive function, and health-related quality of life outcomes after rituximab-methotrexate, BCNU, teniposide, and prednisolone for primary CNS lymphoma: Final results of the HOVON 105/ALLG NHL 24 study

BACKGROUND

Studies on the efficacy of rituximab in primary CNS lymphoma (PCNSL) reported conflicting results. Our international randomized phase 3 study showed that the addition of rituximab to high-dose methotrexate, BCNU, teniposide, and prednisolone (MBVP) in PCNSL was not efficacious in the short term. Here we present long-term results after a median follow-up of 82.3 months.

METHODS

One hundred and ninety-nine eligible newly diagnosed, nonimmunocompromised patients with PCNSL aged 18-70 years with WHO performance status 0-3 was randomized between treatment with MBVP chemotherapy with or without rituximab, followed by high-dose cytarabine consolidation in responding patients, and reduced-dose WBRT in patients aged ≤ 60 years. Event-free survival was the primary endpoint. Overall survival rate, neurocognitive functioning (NCF), and health-related quality of life (HRQoL) were additionally assessed, with the IPCG test battery, EORTC QLQ-C30 and QLQ-BN20 questionnaires, respectively.

RESULTS

For event-free survival, the hazard ratio was 0.85, 95% CI 0.61-1.18, P = .33. Overall survival rate at 5 years for MBVP and R-MBVP was 49% (39-59) and 53% (43-63) respectively. In total, 64 patients died in the MBVP arm and 55 in the R-MBVP arm, of which 69% were due to PCNSL. At the group level, all domains of NCF and HRQoL improved to a clinically relevant extent after treatment initiation, and remained stable thereafter up to 60 months of follow-up, except for motor speed which deteriorated between 24 and 60 months. Although fatigue improved initially, high levels persisted in the long term.

CONCLUSIONS

Long-term follow-up confirms the lack of added value of rituximab in addition to MBVP and HD-cytarabine for PCNSL.

The prognostic value of CD8+ CTLs, CD163+ TAMs, and PDL1 expression in the tumor microenvironment of primary central nervous system lymphoma

To explore immune cell infiltration and PDL1 expression in the tumor microenvironment (TME) of primary central nervous system lymphoma (PCNSL), we performed immunohistochemical staining on paraffin-embedded tumor tissues from 34 patients diagnosed with PCNSL. CD8 and CD163 positive cells were manually counted, and PDL1 expression was quantified by the H-score scoring method in the tumor center and around the tumor. The Kaplan-Meier method was used to analyze the prognostic value of the TME. We found obvious infiltration of CD8+ CTLs and CD163+ TAMs in the TME of PCNSL patients. And PDL1 was expressed in the tumor center as well as around the tumor. Survival analysis showed that high CD8+ CTLs levels and high intratumoral PDL1 expression were significantly correlated with longer OS. High CD8+ CTLs and CD163+ TAMs levels were associated with longer PFS.

Relevance of different prognostic scores in primary CNS lymphoma in the era of intensified treatment regimens: A retrospective, multicenter analysis of 174 patients

OBJECTIVES

Treatment intensification (including consolidative high-dose chemotherapy with autologous stem cell transplantation [HDT-ASCT]) significantly improved outcome in primary central nervous system lymphoma (PCNSL) patients.

METHODS

We conducted a multicenter, retrospective analysis of newly diagnosed PCNSL patients, treated with intensified treatment regimens. The following scores were evaluated in terms of overall survival (OS) and progression-free survival (PFS): Memorial Sloan-Kettering Cancer Center (MSKCC), International Extranodal Lymphoma Study Group (IELSG), and three-factor (3F) prognostic score. Further, all scores were comparatively investigated for model quality and concordance.

RESULTS

Altogether, 174 PCNSL patients were included. One hundred and five patients (60.3%) underwent HDT-ASCT. Two-year OS and 2-year PFS for the entire population were 73.3% and 48.5%, respectively. The MSKCC (p = .003) and 3F score (p < .001), but not the IELSG score (p = .06), had the discriminatory power to identify different risk groups for OS. In regard to concordance, the 3F score (C-index [0.71]) outperformed both the MSKCC (C-index [0.64]) and IELSG (C-index [0.53]) score. Moreover, the superiority of the 3F score was shown for PFS, successfully stratifying patients in three risk groups, which also resulted in the highest C-index (0.66).

CONCLUSION

The comparative analysis of established PCNSL risk scores affirm the clinical utility of the 3F score stratifying the widest prognostic spectrum among PCNSL patients treated with intensified treatment approaches.

High-dose chemotherapy and autologous haematopoietic stem-cell transplantation in older, fit patients with primary diffuse large B-cell CNS lymphoma (MARTA): a single-arm, phase 2 trial

BACKGROUND

Available treatments for older patients with primary diffuse large B-cell CNS lymphoma (PCNSL) offer progression-free survival of up to 16 months. We aimed to investigate an intensified treatment of high-dose chemotherapy and autologous haematopoietic stem-cell transplantation (HSCT) in older patients with PCNSL.

METHODS

MARTA was a prospective, single-arm, phase 2 study done at 15 research hospitals in Germany. Patients aged 65 years or older with newly diagnosed, untreated PCNSL were enrolled if they had an Eastern Cooperative Oncology Group performance status of 0-2 and were fit for high-dose chemotherapy and autologous HSCT. Induction treatment consisted of two 21-day cycles of high-dose intravenous methotrexate 3·5 g/m2 (day 1), intravenous cytarabine 2 g/m2 twice daily (days 2 and 3), and intravenous rituximab 375 mg/m2 (days 0 and 4) followed by high-dose chemotherapy with intravenous rituximab 375 mg/m2 (day -8), intravenous busulfan 3·2 mg/kg (days -7 and -6), and intravenous thiotepa 5 mg/kg (days -5 and -4) plus autologous HSCT. The primary endpoint was progression-free survival at 12 months in all patients who met eligibility criteria and started treatment. The study was registered with the German clinical trial registry, DRKS00011932, and recruitment is complete.

FINDINGS

Between Nov 28, 2017, and Sept 16, 2020, 54 patients started induction treatment and 51 were included in the full analysis set. Median age was 71 years (IQR 68-75); 27 (53%) patients were female and 24 (47%) were male. At a median follow-up of 23·0 months (IQR 16·8-37·4), 23 (45%) of 51 patients progressed, relapsed, or died. 12-month progression-free survival was 58·8% (80% CI 48·9-68·2; 95% CI 44·1-70·9). During induction treatment, the most common grade 3-5 toxicities were thrombocytopenia and leukopenia (each in 52 [96%] of 54 patients). During high-dose chemotherapy and autologous HSCT, the most common grade 3-5 toxicity was leukopenia (37 [100%] of 37 patients). Treatment-related deaths were reported in three (6%) of 54 patients, all due to infectious complications.

INTERPRETATION

Although the primary efficacy threshold was not met, short induction followed by high-dose chemotherapy and autologous HSCT is active in selected older patients with PCNSL and could serve as a benchmark for comparative trials.

FUNDING

Else Kröner-Fresenius Foundation, Riemser Pharma, and Medical Center-University of Freiburg.

Entirely noninvasive outcome prediction in central nervous system lymphomas using circulating tumor DNA

ABSTRACT

State-of-the-art response assessment of central nervous system lymphoma (CNSL) by magnetic resonance imaging is challenging and an insufficient predictor of treatment outcomes. Accordingly, the development of novel risk stratification strategies in CNSL is a high unmet medical need. We applied ultrasensitive circulating tumor DNA (ctDNA) sequencing to 146 plasma and cerebrospinal fluid (CSF) samples from 67 patients, aiming to develop an entirely noninvasive dynamic risk model considering clinical and molecular features of CNSL. Our ultrasensitive method allowed for the detection of CNSL-derived mutations in plasma ctDNA with high concordance to CSF and tumor tissue. Undetectable plasma ctDNA at baseline was associated with favorable outcomes. We tracked tumor-specific mutations in plasma-derived ctDNA over time and developed a novel CNSL biomarker based on this information: peripheral residual disease (PRD). Persistence of PRD after treatment was highly predictive of relapse. Integrating established baseline clinical risk factors with assessment of radiographic response and PRD during treatment resulted in the development and independent validation of a novel tool for risk stratification: molecular prognostic index for CNSL (MOP-C). MOP-C proved to be highly predictive of outcomes in patients with CNSL (failure-free survival hazard ratio per risk group of 6.60; 95% confidence interval, 3.12-13.97; P < .0001) and is publicly available at www.mop-c.com. Our results highlight the role of ctDNA sequencing in CNSL. MOP-C has the potential to improve the current standard of clinical risk stratification and radiographic response assessment in patients with CNSL, ultimately paving the way toward individualized treatment.

Improved early outcome prediction by MRI-based 3D tumor volume assessment in patients with CNS lymphomas

BACKGROUND

Central nervous system lymphomas (CNSL) display remarkable clinical heterogeneity, yet accurate prediction of outcomes remains challenging. The IPCG criteria are widely used in routine practice for the assessment of treatment response. However, the value of the IPCG criteria for ultimate outcome prediction is largely unclear, mainly due to the uncertainty in delineating complete from partial responses during and after treatment.

METHODS

We explored various MRI features including semi-automated 3D tumor volume measurements at different disease milestones and their association with survival in 93 CNSL patients undergoing curative-intent treatment.

RESULTS

At diagnosis, patients with more than 3 lymphoma lesions, periventricular involvement, and high 3D tumor volumes showed significantly unfavorable PFS and OS. At first interim MRI during treatment, the IPCG criteria failed to discriminate outcomes in responding patients. Therefore, we randomized these patients into training and validation cohorts to investigate whether 3D tumor volumetry could improve outcome prediction. We identified a 3D tumor volume reduction of ≥97% as the optimal threshold for risk stratification (=3D early response, 3D_ER). Applied to the validation cohort, patients achieving 3D_ER had significantly superior outcomes. In multivariate analyses, 3D_ER was independently prognostic of PFS and OS. Finally, we leveraged prognostic information from 3D MRI features and circulating biomarkers to build a composite metric that further improved outcome prediction in CNSL.

CONCLUSIONS

We developed semi-automated 3D tumor volume measurements as strong and independent early predictors of clinical outcomes in CNSL patients. These radiologic features could help improve risk stratification and help guide future treatment approaches.

Diagnostic, Pathologic, and Therapeutic Considerations for Primary CNS Lymphoma

Primary CNS lymphoma (PCNSL) is a rare lymphoma representing 3% of CNS malignancies. The diagnosis is complicated by the unique risks associated with brain biopsy, and the treatment is similarly complicated by the restriction of effective therapeutics able to cross the blood-brain barrier. Currently, the majority of individuals diagnosed with this disease are immunocompetent although immune deficiency related to HIV or immunosuppressive therapy remains an important risk factor. Improvements in both frontline therapy and consolidation options, including the use of hematopoietic stem-cell transplantation, have translated to improved survival. Unfortunately, patients experiencing relapsed or refractory disease often fare poorly. Here, we review key clinical, pathologic, and therapeutic aspects of PCNSL and highlight challenging clinical scenarios that may be encountered by the treating oncologist.

CT-defined sarcopenia predicts treatment response in primary central nervous system lymphomas

OBJECTIVE

Body composition assessment derived from cross-sectional imaging has shown promising results as a prognostic biomarker in several tumor entities. Our aim was to analyze the role of low skeletal muscle mass (LSMM) and fat areas for prognosis of dose-limiting toxicity (DLT) and treatment response in patients with primary central nervous system lymphoma (PCNSL).

METHODS

Overall, 61 patients (29 female patients, 47.5%) with a mean age of 63.8 ± 12.2 years, range 23-81 years, were identified in the data base between 2012 and 2020 with sufficient clinical and imaging data. Body composition assessment, comprising LSMM and visceral and subcutaneous fat areas, was performed on one axial slice on L3-height derived from staging computed tomography (CT) images. DLT was assessed during chemotherapy in clinical routine. Objective response rate (ORR) was measured on following magnetic resonance images of the head accordingly to the Cheson criteria.

RESULTS

Twenty-eight patients had DLT (45.9%). Regression analysis revealed that LSMM was associated with objective response, OR = 5.19 (95% CI 1.35-19.94, p = 0.02) (univariable regression), and OR = 4.23 (95% CI 1.03- 17.38, p = 0.046) (multivariable regression). None of the body composition parameters could predict DLT. Patients with normal visceral to subcutaneous ratio (VSR) could be treated with more chemotherapy cycles compared to patients with high VSR (mean, 4.25 vs 2.94, p = 0.03). Patients with ORR had higher muscle density values compared to patients with stable and/or progressive disease (34.46 ± vs 28.18 ± HU, p = 0.02).

CONCLUSIONS

LSMM is strongly associated with objective response in patients with PCNSL. Body composition parameters cannot predict DLT.

CLINICAL RELEVANCE STATEMENT

Low skeletal muscle mass on computed tomography (CT) is an independent prognostic factor of poor treatment response in central nervous system lymphoma. Analysis of the skeletal musculature on staging CT should be implemented into the clinical routine in this tumor entity.

KEY POINTS

• Low skeletal muscle mass is strongly associated with the objective response rate. • No body composition parameters could predict dose-limiting toxicity.

Utility of contrast-enhanced MRI radiomics features combined with clinical indicators for predicting induction chemotherapy response in primary central nervous system lymphoma

PURPOSE

To assess the utility of combining contrast-enhanced magnetic resonance imaging (CE-MRI) radiomics features with clinical variables in predicting the response to induction chemotherapy (IC) for primary central nervous system lymphoma (PCNSL).

METHODS

A total of 131 patients with PCNSL (101 in the training set and 30 in the testing set) who had undergone contrast-enhanced MRI scans were retrospectively analyzed. Pyradiomics was utilized to extract radiomics features, and the clinical variables of the patients were gathered. Radiomics prediction models were developed using different combinations of feature selection methods and machine learning models, and the best combination was ultimately chosen. We screened clinical variables associated with treatment outcomes and developed clinical prediction models. The predictive performance of radiomics model, clinical model, and combined model, which integrates the best radiomics model and clinical characteristics, was independently assessed and compared using Receiver Operating Characteristic (ROC) curves.

RESULTS

In total, we extracted 1598 features. The best radiomics model we selected as the best utilized T-test and Recursive Feature Elimination (RFE) for feature selection and logistic regression for model building. Serum Interleukin 2 Receptor (IL-2R) and Eastern Cooperative Oncology Group (ECOG) Score were utilized to develop a clinical predictive model for assessing the response to induction chemotherapy. The results of the testing set revealed that the combined prediction model (radiomics and IL-2R) achieved the highest area under the ROC curve at 0.868 (0.683, 0.967), followed by the radiomics model at 0.857 (0.681, 0.957), and the clinical prediction model (IL-2R and ECOG) at 0.618 (0.413, 0.797). The combined model was significantly more accurate than the clinical model, with an AUC of 0.868 compared to 0.618 (P < 0.05). While the radiomics model had slightly better predictive power than the clinical model, this difference was not statistically significant (AUC, 0.857 vs. 0.618, P > 0.05).

CONCLUSIONS

Our prediction model, which combines radiomics signatures from CE-MRI with serum IL-2R, can effectively stratify patients with PCNSL before high-dose methotrexate (HD-MTX) -based chemotherapy.

Detecting Double Expression Status in Primary Central Nervous System Lymphoma Using Multiparametric MRI Based Machine Learning

BACKGROUND

Double expression lymphoma (DEL) is a subtype of primary central nervous system lymphoma (PCNSL) that often has a poor prognosis. Currently, there are limited noninvasive ways to detect protein expression.

PURPOSE

To detect DEL in PCNSL using multiparametric MRI-based machine learning.

STUDY TYPE

Retrospective.

POPULATION

Forty PCNSL patients were enrolled in the study among whom 17 were DEL (9 males and 8 females, 61.29 ± 14.14 years) and 23 were non-DEL (14 males and 9 females, 55.57 ± 14.16 years) with 59 lesions (28 DEL and 31 non-DEL).

FIELD STRENGTH/SEQUENCE

ADC map derived from DWI (b = 0/1000 s/mm2 ), fast spin echo T2WI, T2FLAIR, and contrast-enhanced T1 weighted imaging (T1CE) were collected at 3.0 T.

ASSESSMENT

Two raters manually segmented lesions by ITK-SNAP on ADC, T2WI, T2FLAIR and T1CE. A total of 2234 radiomics features from the tumor segmentation area were extracted. The t-test was conducted to filter the features, and elastic net regression algorithm combined with recursive feature elimination was used to calculate the essential features. Finally, 12 groups with combinations of different sequences were fitted to 6 classifiers, and the optimal models were selected.

STATISTICAL TESTS

Continuous variables were assessed by the t-test, while categorical variables were assessed by the non-parametric test. Interclass correlation coefficient tested variables' consistency. Sensitivity, specificity, accuracy F1-score, and area under the curve (AUC) were used to evaluate model performance.

RESULTS

DEL status could be identified to varying degrees with 72 models based on radiomics, and model performance could be improved by combining different sequences and classifiers. Both SVMlinear and logistic regression (LR) combined with four sequence group had similar largest AUCmean (0.92 ± 0.09 vs. 0.92 ± 0.05), and SVMlinear was considered as the optimal model in this study since the F1-score of SVMlinear (0.88) was higher than that of LR (0.83).

DATA CONCLUSION

Multiparametric MRI-based machine learning is promising in DEL detection.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY STAGE: 2.

Three-year follow-up analysis of phase 1/2 study on tirabrutinib in patients with relapsed or refractory primary central nervous system lymphoma

Background

The ONO-4059-02 phase 1/2 study showed favorable efficacy and acceptable safety profile of tirabrutinib, a second-generation Bruton's tyrosine kinase inhibitor, for relapsed/refractory primary central nervous system lymphoma (PCNSL). Here, we report the long-term efficacy and safety after a 3-year follow-up.

Methods

Eligible patients were aged ≥ 20 years with histologically diagnosed PCNSL and KPS of ≥ 70. Patients received oral tirabrutinib once daily at 320 or 480 mg, or 480 mg under fasted conditions.

Results

Between October 19, 2017, and June 13, 2019, 44 patients were enrolled: 33 and 9 had relapsed and refractory, respectively. The 320, 480, and 480 mg fasted groups included 20, 7, and 17 patients, respectively. The median follow-up was 37.1 months. The overall response rate was 63.6% (95% CI: 47.8-77.6) with complete response (CR), unconfirmed CR, and partial response in 9, 7, and 12 patients, respectively. The median duration of response (DOR) was 9.2 months, with a DOR rate of 19.8%; the median progression-free survival (PFS) and median overall survival (OS) were 2.9 months and not reached, respectively, with PFS and OS rates of 13.9% and 56.7%, respectively. Adverse events occurred in 38 patients (86.4%): grade ≥ 3 in 23 (52.3%) including 1 patient with grade 5 events. KPS and quality of life (QoL) scores were well maintained among patients receiving long-term treatment.

Conclusions

The results demonstrated the long-term clinical benefit of tirabrutinib, with deep and durable response in a subset of patients and acceptable safety profile, while KPS and QoL scores were maintained.

Molecular Analysis of Liquid Vitreous Biopsy Reveals Occult Lymphoma Following Cytology-Negative Biopsies of the Brain and Vitreous

PURPOSE

Primary central nervous system lymphoma (PCNSL) is a rare but deadly malignancy that principally affects adults in the fifth and sixth decades of life. Despite diagnostic advances in analyses of cerebral spinal fluid and neuroimaging, definitive diagnosis of PCNSL requires primary brain tissue biopsy. While small neurosurgical biopsy volumes are pursued to minimize removal of normal brain tissue, the spatial margins to precisely biopsy pathologic tissue are narrow and can result in missed diagnoses. Furthermore, prior steroid treatment can significantly reduce tumor burden increasing the likelihood of a non-diagnostic biopsy.

METHODS

A retrospective case report from a tertiary referral center using a combination of neuroradiological studies, sterotactic tissue biopsy, and molecular testing for genome mutations.

RESULTS

A 72-year-old woman with strong suspicion for PCNSL clinically and radiologically, but cerebral spinal fluid and primary brain tissue biopsy were negative for tumor. However, vitreous liquid biopsy molecular testing for a MYD88 mutation as well as B-cell clonality (IGH/IGK rearrangement) were positive, indicating the presence of secondary vitreoretinal lymphoma from PCNSL. Only after autopsy of her brain was histopathological and immunohistochemical evidence of PCNSL confirmed.

CONCLUSION

This case illustrates the unique contribution of liquid biopsy neuropathology-oriented molecular testing in a challenging case with high clinical suspicion of PCNSL in which gold-standard diagnostic testing failed to yield a diagnosis.

A phase 2 study of ibrutinib maintenance following first-line high-dose methotrexate-based chemotherapy for elderly patients with primary central nervous system lymphoma

BACKGROUND

Elderly patients account for nearly 70% of all primary central nervous system lymphoma (PCNSL) cases. They cannot tolerate aggressive treatment and have poor prognosis with a median overall survival (OS) of less than 2 years and progression-free survival (PFS) of 6-16 months. Ibrutinib penetrates the blood-brain barrier and has shown activity in PCNSL.

METHODS

This prospective study investigated whether ibrutinib maintenance is feasible, and whether it can benefit elderly PCNSL patients in terms of expected 2-year PFS. It is an open label, phase 2 study in newly diagnosed PCNSL patients 60-85 years old who responded to first-line high-dose methotrexate (HDMTX)-based treatment with partial or complete response. Ibrutinib maintenance (560 mg/d) was continued until disease progression or intolerable toxicity.

RESULTS

Twenty patients were enrolled, with a median age of 72 years (range, 61-80). Median time on ibrutinib maintenance was 12.5 (range, 2-46) months. Twelve patients stopped treatment: five due to central nervous system relapse and seven due to adverse events that were mainly grade 2. Five patients died (25%) all due to relapse. The 1- and 2-year PFS are 90% and 72.6%, respectively, and the 2-year OS is 89%.

CONCLUSIONS

The study reached its primary end points and also showed that ibrutinib maintenance is tolerated reasonably well by the elderly. Therefore, this study supports the concept that ibrutinib maintenance should be further evaluated as an optional consolidation measure in the elderly.

Standardized brain tumor imaging protocols for clinical trials: current recommendations and tips for integration

Standardized MRI acquisition protocols are crucial for reducing the measurement and interpretation variability associated with response assessment in brain tumor clinical trials. The main challenge is that standardized protocols should ensure high image quality while maximizing the number of institutions meeting the acquisition requirements. In recent years, extensive effort has been made by consensus groups to propose different "ideal" and "minimum requirements" brain tumor imaging protocols (BTIPs) for gliomas, brain metastases (BM), and primary central nervous system lymphomas (PCSNL). In clinical practice, BTIPs for clinical trials can be easily integrated with additional MRI sequences that may be desired for clinical patient management at individual sites. In this review, we summarize the general concepts behind the choice and timing of sequences included in the current recommended BTIPs, we provide a comparative overview, and discuss tips and caveats to integrate additional clinical or research sequences while preserving the recommended BTIPs. Finally, we also reflect on potential future directions for brain tumor imaging in clinical trials.

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 ± 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.

Clinical efficacy and safety of chimeric antigen receptor T-cell therapy for mantle cell lymphoma with secondary central nervous system involvement

Data describing outcomes of chimeric antigen receptor (CAR) T-cell therapy in patients with secondary central nervous system (SCNS) involvement of mantle cell lymphoma (MCL) are limited. We identified 10 patients with MCL and SCNS involvement treated with anti-CD19 CAR T-cell therapy at three US academic centres. Frequent objective responses were observed in the CNS (86%) and systemically (90%), and the 1-year progression-free survival was 47%. Seven patients developed immune-effector-cell-associated-neurotoxicity-syndrome (n = 2 Grade 1, n = 5 Grade 3). Our results suggest that anti-CD19 CAR T-cell therapy in this setting is feasible and additional data regarding neurotoxicity in this population may be warranted.

Central Nervous System Lymphoma

Central nervous system lymphoma (CNSL) is a rare and aggressive malignancy that primarily affects the brain, spinal cord, and meninges. This article provides a comprehensive overview of the current understanding of CNSL encompassing its epidemiology, pathophysiology, clinical presentation, diagnosis, treatment modalities, and prognosis. Although the main focus is on primary CNS lymphoma (PCNSL), ocular lymphoma, primary leptomeningeal lymphoma, and secondary CNS lymphoma are also discussed. The pathobiology of CNSL involves the infiltration of malignant lymphocytes within the CNS parenchyma or leptomeninges. Various risk factors and immunological mechanisms contribute to its development, including immunodeficiency states, chronic inflammation, and genomic alterations. Accurate diagnosis is crucial for appropriate management, given the heterogeneous clinical presentation. The neuroimaging, systemic imaging, and other modalities for diagnosis and evaluation for extent of disease involvement will be discussed. Additionally, the importance of histopathological examination, cerebrospinal fluid (CSF) analysis, and molecular testing in confirming the diagnosis and guiding treatment decisions are highlighted. The treatment landscape for CNSL has evolved significantly. Therapeutic approaches encompass a multimodal strategy combining high-dose methotrexate-based chemotherapy, consolidation with whole-brain radiation therapy, and high-dose chemotherapy with stem cell rescue. Recent advancements in targeted therapies and immunomodulatory agents offer promising avenues for future treatment options. We review the clinical outcomes and prognostic factors influencing the survival of CNSL patients, including age, performance status, disease stage, and genetic abnormalities.

Evidence-based management of primary and secondary CNS lymphoma

Central nervous system (CNS) lymphoma has traditionally had very poor outcomes however advances in management have resulted in dramatic improvements and long-term survival of patients. We describe the evidence for treatment strategies for these aggressive disorders. In primary CNS lymphoma there are randomized trial data to inform treatment decisions but these are lacking to guide management in secondary CNS lymphoma. Dynamic assessment of patient fitness and frailty is key throughout treatment, alongside delivery of CNS-bioavailable therapy and enrolment in clinical trials, at each stage of the disease. Intensive high-dose methotrexate-containing induction followed by consolidation with autologous stem cell transplantation with thiotepa-based conditioning is recommended for patients who are fit. Less intensive chemoimmunotherapy, novel agents (including Bruton tyrosine kinase inhibitors, cereblon targeting immunomodulatory agents, and checkpoint inhibitors in the context of clinical trials), and whole brain radiotherapy may be reserved for less fit patients or disease which is chemoresistant. Data regarding the efficacy of chimeric antigen receptor T-cells therapy is emerging, and concerns regarding greater toxicity have not been realized. Future areas of prospective studies include the identification of those at high risk of developing CNS lymphoma, management in elderly or frail patients as well as incorporating novel agents into regimens, particularly for those with chemoresistant disease.

Primary brain tumours in adults

The most frequent adult-type primary CNS tumours are diffuse gliomas, but a large variety of rarer CNS tumour types exists. The classification of these tumours is increasingly based on molecular diagnostics, which is reflected in the extensive molecular foundation of the recent WHO 2021 classification of CNS tumours. Resection as extensive as is safely possible is the cornerstone of treatment in most gliomas, and is now also recommended early in the treatment of patients with radiological evidence of histologically low-grade tumours. For the adult-type diffuse glioma, standard of care is a combination of radiotherapy and chemotherapy. Although treatment with curative intent is not available, combined modality treatment has resulted in long-term survival (>10-20 years) for some patients with isocitrate dehydrogenase (IDH) mutant tumours. Other rarer tumours require tailored approaches, best delivered in specialised centres. Targeted treatments based on molecular alterations still only play a minor role in the treatment landscape of adult-type diffuse glioma, and today are mainly limited to patients with tumours with BRAFV600E (ie, Val600Glu) mutations. Immunotherapy for CNS tumours is still in its infancy, and so far, trials with checkpoint inhibitors and vaccination studies have not shown improvement in patient outcomes in glioblastoma. Current research is focused on improving our understanding of the immunosuppressive tumour environment, the molecular heterogeneity of tumours, and the role of tumour microtube network connections between cells in the tumour microenvironment. These factors all appear to play a role in treatment resistance, and indicate that novel approaches are needed to further improve outcomes of patients with CNS tumours.

Evaluation of progression-free survival as a surrogate end point in primary CNS lymphoma: a systematic review and meta-analysis

Purpose: To evaluate progression-free survival (PFS) as early surrogate endpoints for overall survival (OS) in primary CNS lymphoma (PCNSL). Methods: PubMed, Embase and Cochrane Central Library were searched up to 7 June 2022. Trial-level analyses were performed by weighted linear regression of logarithmic hazard ratios for PFS and OS. Treatment arm-level analyses were performed between PFS rates and 3- or 5-year OS rates. Results: 1471 PCNSL patients in nine randomized control trials were included. PFS was associated with OS (r = 0.750; 95% CI: 0.228-0.937). Strong linear correlations existed between 1-, 2- and 3-year PFS and 3-year OS (r = 0.896-0.928), moderate or weak correlations existed between 3- to 6-month PFS and 3-year OS, 3-month to 5-year PFS and 5-year OS. Conclusion: Short-term PFS can validly substitute for long-term OS in PCNSL.

Residual diffusion-weighted imaging hyperintense signal in primary central nervous system lymphoma can predict early recurrence

BACKGROUND

The treatment response of primary central nervous system lymphomas (PCNSLs) is mainly evaluated using postcontrast T1-weighted imaging (T1WI). Because poorly enhanced lesions may contain residual tumors, the combination of evaluation methods will potentially improve the accuracy of determining treatment effectiveness. In this study, we evaluated the usefulness of diffusion-weighted imaging (DWI) in predicting recurrence among patients with PCNSL who achieved complete response (CR)/unconfirmed CR (CRu).

METHODS

Fifty-four patients newly diagnosed with PCNSL who were treated at our institution and achieved CR/CRu at the end of treatment were included in this study. The patients were divided into two groups according to the presence or absence of residual DWI hyperintense signal at the tumor site at the end of treatment. Kaplan-Meier analysis was performed to analyze the median overall survival (OS) and progression-free survival (PFS).

RESULTS

The mean age of the 54 patients was 66.4 ± 13.3 years. The induction therapies were HD-MTX in 20 patients, R-MPV in 29 patients, and other chemotherapies in five patients. Radiotherapy was performed in 35 patients, high-dose cytarabine therapy in 14 patients, and autologous hematopoietic stem cell transplantation in one patient, and of the 54 patients, 10 had no consolidation therapy. The residual DWI hyperintense signal sign was observed in 18 patients. The R-MPV regimen was statistically associated with a lower rate of residual DWI hyperintense signal (p = 0.0453). The median PFS was statistically shorter in the residual DWI hyperintense signal group than in the non-residual DWI hyperintense signal group (14.0 months vs. 85.1 months) (p < 0.0001, log-rank test).

CONCLUSION

A residual DWI hyperintense signal at the end of treatment was statistically associated with shorter PFS. Among patients who achieved CR/CRu evaluated based on postcontrast T1WI, DWI could be a valuable additional sequence to predict the early recurrence of PCNSL.

Prognostic model and treatment choices for patients with primary intracranial central nervous system lymphoma: A population-based study

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a non-Hodgkin lymphoma that occurs in the CNS. With the advancement of medical care, its prognosis and treatment have also undergone tremendous changes. This study aimed to construct a prognostic model and compare the effects of different treatments for intracranial PCNSL.

METHODS

Cases diagnosed as PCNSL between 2004 and 2015 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Data were analyzed using Kaplan-Meier method and Cox regression analysis. Nomogram was built and validated using the R program.

RESULTS

A total of 2861 PCNSL patients were included in the analysis. Age, year of diagnosis, surgery and chemotherapy were independent predictors for both overall survival (OS) and cancer-specific survival (CSS). A nomogram was established to predict 3-, 5- and 10-year OS and CSS for patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) showed the nomogram had good predictive performance and clinical application value. We also revealed that gross total resection had significantly better OS and CSS than biopsy alone (P < 0.001). Patients who received only chemotherapy had the best prognosis and did not benefit from additional radiotherapy.

CONCLUSION

We developed a nomogram to predict patient survival rates based on independent predictors. It is an effective tool to help clinicians make survival predictions. Our results showed that patients can benefit from gross total resection of tumor, if it is feasible, and chemotherapy. The role of radiotherapy remained to be further assessed.

[18F]FDG PET-MRI provides survival biomarkers in primary central nervous system lymphoma in the elderly: an ancillary study from the BLOCAGE trial of the LOC network

PURPOSE

Primary central nervous system lymphoma (PCNSL) incidence is rising among elderly patients, presenting challenges due to poor prognosis and treatment-related toxicity risks. This study explores the potential of combining [18F]fluorodeoxyglucose ([18F]FDG) PET scans and multimodal MRI for improving management in elderly patients with de novo PCNSL.

METHODS

Immunocompetent patients over 60 years with de novo PCNSL were prospectively enrolled in a multicentric study between January 2016 and April 2021. Patients underwent brain [18F]FDG PET-MRI before receiving high-dose methotrexate-based chemotherapy. Relationships between extracted PET (metabolic tumor volume (MTV), sum of MTV for up to five lesions (sumMTV), metabolic imaging lymphoma aggressiveness score (MILAS)) and MRI parameters (tumor contrast-enhancement size, cerebral blood volume (CBV), cerebral blood flow (CBF), apparent diffusion coefficient (ADC)) and treatment response and outcomes were analyzed.

RESULTS

Of 54 newly diagnosed diffuse large B-cell PCNSL patients, 52 had positive PET and MRI with highly [18F]FDG-avid and contrast-enhanced disease (SUVmax: 27.7 [22.8-36]). High [18F]FDG uptake and metabolic volume were significantly associated with low ADCmean values and high CBF at baseline. Among patients, 69% achieved an objective response at the end of induction therapy, while 17 were progressive. Higher cerebellar SUVmean and lower sumMTV at diagnosis were significant predictors of complete response: 6.4 [5.7-7.7] vs 5.4 [4.5-6.6] (p = 0.04) and 5.5 [2.1-13.3] vs 15.9 [4.2-19.5] (p = 0.01), respectively. Two-year overall survival (OS) was 71%, with a median progression-free survival (PFS) of 29.6 months and a median follow-up of 37 months. Larger tumor volumes on PET or enhanced T1-weighted MRI were significant predictors of poorer OS, while a high MILAS score at diagnosis was associated with early death (< 1 year).

CONCLUSION

Baseline cerebellar metabolism and sumMTV may predict response to end of chemotherapy in PCNSL. Tumor volume and MILAS at baseline are strong prognostic factors.

Treatment of new-onset primary central nervous system lymphoma in elderly patients using RMPV chemotherapy: a single-institution experience

The prognosis of primary central nervous system lymphoma (PCNSL) in the elderly remains poor. We aimed to evaluate the outcome of rituximab, methotrexate, procarbazine, and vincristine (RMPV) chemotherapy in elderly patients with new-onset PCNSL. Twenty-eight patients aged ≥ 70 years treated for PCNSL between 2010 and 2020 were examined retrospectively. Nineteen patients received RMPV and nine did not qualify. Patients received five to seven cycles of RMPV plus response-adapted whole-brain radiotherapy (WBRT) and cytarabine. Ten of the 19 patients who received RMPV (52.6%) completed the induction, but only four patients (21.1%) completed RMPV chemotherapy, WBRT 23.4 Gy, and cytarabine. Median progression-free survival (PFS) and overall survival (OS) in the RMPV group was 54.4 and 85.0 months, respectively. Both PFS and OS were significantly longer in patients who received RMPV chemotherapy than in those who did not, and in patients who started but did not complete RMPV than in those who did not receive RMPV. Patients who received incomplete RMPV tended to have a favorable prognosis. Initial treatment with RMPV chemotherapy was effective in elderly patients with PCNSL. Adjusting the number of courses of RMPV may improve the prognosis of elderly patients with PCNSL, but further verification is necessary.

Research Progress of CXCR4-Targeting Radioligands for Oncologic Imaging

C-X-C motif chemokine receptor 4 (CXCR4) plays a key role in various physiological functions, such as immune processes and disease development, and can influence angiogenesis, proliferation, and distant metastasis in tumors. Recently, several radioligands, including peptides, small molecules, and nanoclusters, have been developed to target CXCR4 for diagnostic purposes, thereby providing new diagnostic strategies based on CXCR4. Herein, we focus on the recent research progress of CXCR4-targeting radioligands for tumor diagnosis. We discuss their application in the diagnosis of hematological tumors, such as lymphomas, multiple myelomas, chronic lymphocytic leukemias, and myeloproliferative tumors, as well as nonhematological tumors, including tumors of the esophagus, breast, and central nervous system. Additionally, we explored the theranostic applications of CXCR4-targeting radioligands in tumors. Targeting CXCR4 using nuclear medicine shows promise as a method for tumor diagnosis, and further research is warranted to enhance its clinical applicability.

First line treatments in primary central nervous system lymphomas in young patients

PURPOSE OF REVIEW

The aim of this review is to provide an update on current first-line treatments as well as on-going studies in immunocompetent patients with primary central nervous system lymphomas.

RECENT FINDINGS

High-dose methotrexate (HD-MTX)-based polychemotherapy is widely used in induction treatment (IT). Among HD-MTX-based regimens, the best association is not yet defined. IT should be followed by a consolidation or a maintenance according to patient's age and performance status. Thiotepa-based intensive chemotherapy (IC) followed by autologous stem cell transplantation (ASCT) has improved survival in eligible patients compared to a nonmyeloablative consolidation. Because of the high risk of neurotoxicity, conventional whole brain radiotherapy (WBRT; 36-40 Gy) has been abandoned. Reduced-WBRT (23.4 Gy) is an alternative option in patients under 60 years-old in complete response after IT. Its safety remains to be demonstrated in elderly patients. The benefit of maintenance strategies to reduce the risk of relapse is being assessed in several studies in patients beyond 70 years-old.

SUMMARY

HD-MTX-based polychemotherapy remains the corner stone of the IT, but the best regimen is not yet defined. Clinical trials assessing new IT regimens are ongoing. Intensive consolidation with IC + ASCT benefits patients up to 70 years-old. Predictive factors are under investigation to better define therapeutic response and guide treatment adjustment.

Age-adjusted high-dose chemotherapy followed by autologous stem cell transplantation or conventional chemotherapy with R-MP as first-line treatment in elderly primary CNS lymphoma patients - the randomized phase III PRIMA-CNS trial

BACKGROUND

Older primary central nervous system lymphoma (PCNSL) patients have an inferior prognosis compared to younger patients because available evidence on best treatment is scarce and treatment delivery is challenging due to comorbidities and reduced performance status. High-dose chemotherapy and autologous stem cell transplantation (HCT-ASCT) after high-dose methotrexate (MTX)-based immuno-chemotherapy has become an increasingly used treatment approach in eligible elderly PCNSL patients with promising feasibility and efficacy, but has not been compared with conventional chemotherapy approaches. In addition, eligibility for HCT-ASCT in elderly PCNSL is not well defined. Geriatric assessment (GA) may be helpful in selecting patients for the best individual treatment choice, but no standardized GA exists to date. A randomized controlled trial, incorporating a GA and comparing age-adapted HCT-ASCT treatment with conventional chemotherapy is needed.

METHODS

This open-label, multicenter, randomized phase III trial with two parallel arms will recruit 310 patients with newly diagnosed PCNSL > 65 years of age in 40 centers in Germany and Austria. The primary objective is to demonstrate that intensified chemotherapy followed by consolidating HCT-ASCT is superior to conventional chemotherapy with rituximab, MTX, procarbazine (R-MP) followed by maintenance with procarbazine in terms of progression free survival (PFS). Secondary endpoints include overall survival (OS), event free survival (EFS), (neuro-)toxicity and quality of life (QoL). GA will be conducted at specific time points during the course of the study. All patients will be treated with a pre-phase rituximab-MTX (R-MTX) cycle followed by re-assessment of transplant eligibility. Patients judged transplant eligible will be randomized (1:1). Patients in arm A will be treated with 3 cycles of R-MP followed by maintenance therapy with procarbazine for 6 months. Patients in arm B will be treated with 2 cycles of MARTA (R-MTX/AraC) followed by busulfan- and thiotepa-based HCT-ASCT.

DISCUSSION

The best treatment strategy for elderly PCNSL patients remains unknown. Treatments range from palliative to curative but more toxic therapies, and there is no standardized measure to select patients for the right treatment. This randomized controlled trial will create evidence for the best treatment strategy with the focus on developing a standardized GA to help define eligibility for an intensive treatment approach.

TRIAL REGISTRATION

German clinical trials registry DRKS00024085 registered March 29, 2023.

First-line induction chemotherapy with high-dose methotrexate versus teniposide in patients with newly diagnosed primary central nervous system lymphoma: a retrospective, multicenter cohort study

BACKGROUND

This study aimed to compare the efficacy and safety of high-dose methotrexate (HD-MTX) versus teniposide (TEN) in patients with newly diagnosed immunocompetent primary central nervous system lymphomas (PCNSLs).

METHODS

The study included immunocompetent, adult patients with newly diagnosed PCNSL at 22 centers in China from 2007 to 2016. The patients received HD-MTX or TEN as first-line induction therapy. The objective response rate, progression-free survival, and overall survival were analyzed for each patient cohort.

RESULTS

A total of 96 patients were eligible: 62 received HD-MTX, while 34 received teniposide. The overall response rate was 73.2% and 72.7% in the MTX and the TEN cohorts, respectively (P = 0.627). The median progression-free survival was 28.4 months [95% confidence interval (CI): 13.7-51.2] in the MTX cohort and 24.3 months (95% CI: 16.6-32.1) in the TEN cohort (P = 0.75). The median overall survival was 31 months (95% CI: 26.8-35.2) in the MTX cohort and 32 months (95% CI: 27.6-36.4) in the TEN cohort (P = 0.77). The incidence of any grade of coagulopathy/deep-vein thrombosis and gastrointestinal disorders was significantly higher in the MTX cohort than in the TEN cohort; no significant difference was found in the incidence of other adverse events between the two cohorts.

CONCLUSIONS

This was the first multicenter study using TEN as the main agent compared with HD-MTX in newly diagnosed primary CNS lymphoma. The TEN-based regimen was non-inferior to the HD-MTX-based regimen with similar overall responses.

CLASSIFICATION OF EVIDENCE

This study provided Class III evidence that the teniposide-based regimen was non-inferior to high-dose methotrexate - based regimen with similar overall responses and long-time survival in immunocompetent patients with PCNSL.

Pretreatment diffusion-weighted imaging for prediction of relapsed and refractory primary central nervous system lymphoma

Objectives

A subset of primary central nervous system lymphoma (PCNSL) has been shown to undergo an early relapsed/refractory (R/R) period after first-line chemotherapy. This study investigated the pretreatment clinical and MRI features to predict R/R in PCNSL, emphasizing the apparent diffusion coefficient (ADC) values in diffusion-weighted imaging (DWI).

Methods

This retrospective study investigated the pretreatment MRI features for predicting R/R in PCNSL. Only patients who had undergone complete preoperative and postoperative MRI follow-up studies were included. From January 2006 to December 2021, 52 patients from two medical institutions with a diagnosis of PCNSL were included (median follow-up time, 26.3 months). Among these, 24 (46.2%) had developed R/R (median time to relapse, 13 months). Cox proportional hazard regression analyses were performed to determine hazard ratios for all parameters.

Results

Significant predictors of R/R in PCNSL were female sex, complete response (CR) to first-line chemotherapy, and ADC value/ratio (p < 0.05). Cut-off points of ADC values and ADC ratios for prediction of R/R were 0.68 × 10-3 mm2/s and 0.97, with AUCs of 0.78 and 0.77, respectively (p < 0.05). Multivariate Cox proportional hazards analysis showed that failure of CR to first-line chemotherapy and low ADC values (<0.68 × 10-3 mm2/s) were significant risk factors for R/R, with hazard ratios of 5.22 and 14.45, respectively (p < 0.05). Kaplan-Meier analysis showed that lower ADC values and ratios predicted significantly shorter progression-free survival (p < 0.05).

Conclusion

Pretreatment ADC values in DWI offer quantitative valuable information for the treatment planning in PCNSL.

Age, CD34+ cell dose, conditioning and pre-transplant cytopenias can help predict transfusion support in lymphoma patients undergoing autologous stem cell transplantation

BACKGROUND AND OBJECTIVES

Autologous stem cell transplant (ASCT) is a widely used therapy for lymphoma patients and can nowadays be performed on an outpatient basis. This study aimed to describe transfusion support in lymphoma patients undergoing ASCT and identify increased or prolonged transfusion requirement predictors.

MATERIALS AND METHODS

A retrospective study of all consecutive lymphoma patients undergoing ASCT between 2010 and 2020.

RESULTS

Out of 226 patients, 145 (64%) received red blood cell (RBC) transfusions, whereas all 226 (100%) required platelet transfusion (PT). Transfusions between Day +1 and +30 were higher in patients over 60 (2 [1-4] vs. 2 [0-2] RBC; p = 0.001 and 4 [2-8] vs. 3 [2-4] PT; p < 0.001); patients with pre-transplant anaemia (4 [2.5-6] vs. 2 [0-2] RBC; p < 0.001 and 5 [3-9] vs. 3 [2-4] PT; p = 0.001); pre-transplant thrombocytopenia (2 [1-4] vs. 2 [0-2] RBC; p < 0.001 and 4 [3-8.5] vs. 2 [1-3] PT; p < 0.001) or CD34+ cell dose <4 × 106 /kg (2 [0-4] vs. 2 [0-2] RBC; p = 0.024 and 4 [2-6] vs. 2 [1-3.5] PT; p < 0.001). RBC transfusion independence was reached later in patients receiving carmustine, cytarabine, etoposide and melphalan (BEAM) (hazard ratio [HR] 1.6; confidence interval [CI] 1.1-2.3) and those requiring RBC before infusion and/or with pre-transplant anaemia (HR 2.2; CI 1.4-3.4). Age above 60 (HR 1.4; CI 1.0-1.9), BEAM conditioning (HR 1.4; CI 1.0-2.0) and pre-transplant thrombocytopenia and/or requiring PT before infusion (HR 1.8; CI 1.4-2.5) entailed longer time until PT independence.

CONCLUSION

These four factors (age ≥60 years; BEAM conditioning, CD34+ dose <4 × 106 /kg and pre-transplant cytopenia and/or Day -10 to 0 transfusion) allowed dividing patients into three groups with significant differences between them regarding the time until transfusion independence.

Early MRI Predictors of Relapse in Primary Central Nervous System Lymphoma Treated with MATRix Immunochemotherapy

Primary Central Nervous System Lymphoma (PCNSL) is a highly malignant brain tumour. We investigated dynamic changes in tumour volume and apparent diffusion coefficient (ADC) measurements for predicting outcome following treatment with MATRix chemotherapy in PCNSL. Patients treated with MATRix (n = 38) underwent T1 contrast-enhanced (T1CE) and diffusion-weighted imaging (DWI) before treatment, after two cycles and after four cycles of chemotherapy. Response was assessed using the International PCNSL Collaborative Group (IPCG) imaging criteria. ADC histogram parameters and T1CE tumour volumes were compared among response groups, using one-way ANOVA testing. Logistic regression was performed to examine those imaging parameters predictive of response. Response after two cycles of chemotherapy differed from response after four cycles; of the six patients with progressive disease (PD) after four cycles of treatment, two (33%) had demonstrated a partial response (PR) or complete response (CR) after two cycles. ADC_mean at baseline, T1CE at baseline and T1CE percentage volume change differed between response groups (0.005 < p < 0.038) and were predictive of MATRix treatment response (area under the curve: 0.672-0.854). Baseline ADC and T1CE metrics are potential biomarkers for risk stratification of PCNSL patients early during remission induction therapy with MATRix. Standard interim response assessment (after two cycles) according to IPCG imaging criteria does not reliably predict early disease progression in the context of a conventional treatment approach.

Clinical applications of circulating tumor DNA in central nervous system lymphoma

Detection and characterization of circulating tumor DNA (ctDNA) in body fluids have the potential to revolutionize management of patients with lymphoma. Minimal access to malignant DNA through a simple blood draw or lumbar puncture is particularly appealing for CNS lymphomas (CNSL), which cannot be easily or repeatedly sampled without invasive surgeries. Profiling of ctDNA provides a real-time snapshot of the genetic composition in patients with CNSL and enables ultrasensitive quantification of lymphoma burden at any given time point during the course of the disease. Here, we broadly review technical challenges of ctDNA identification in CNSL, recent advances of innovative liquid biopsy technologies, potential clinical applications of ctDNA and how it may improve CNSL risk stratification, outcome prediction, and monitoring of measurable residual disease. Finally, we discuss clinical trials and scenarios in which ctDNA could be implemented to guide risk-adapted and personalized treatment decisions.

Prognostic impact of peripheral natural killer cells in primary central nervous system lymphoma

Background

Primary central nervous system lymphoma (PCNSL) is an aggressive extranodal non-Hodgkin lymphoma with a poor prognosis. We aimed to evaluate the prognostic impact of circulating NK cells in PCNSL.

Materials and methods

Patients diagnosed with PCNSL who were treated at our institution between December 2018 and December 2019 were retrospectively screened. Patient variables including age, sex, Karnofsky performance status, diagnostic methods, location of lesions, lactate dehydrogenase, cerebrospinal fluids (CSF), and vitreous fluids involvement or not were documented. NK cell count and NK cell proportion (NK cell count/lymphocyte count) in the peripheral blood were evaluated by flow cytometry. Some patients underwent two consecutive NK cell tests before and three weeks after chemotherapy (before the next chemotherapy). The fold change in NK cell proportion and NK cell counts were calculated. CD56-positive NK cells in tumor tissue were assessed by immunohistochemistry. NK cell cytotoxicity assay was performed using flow cytometry.

Results

A total of 161 patients with PCNSL were included in this study. The median NK cell count of all NK cell tests was 197.73/μL (range 13.11-1889.90 cells/μL). The median proportion of NK cells was 14.11% (range 1.68-45.15%) for all. Responders had a higher median NK cell count (p<0.0001) and NK cell proportion (p<0.0001) than non-responders. Furthermore, Responders had a higher median fold change in NK cell proportion than non-responders (p=0.019) or patients in complete remission/partial remission (p<0.0001). A higher median fold change in NK cell count was observed in responders than in non-responders (p=0.0224) or patients in complete remission/partial remission (p=0.0002). For newly diagnosed PCNSL, patients with a high NK cell count (>165 cells/μL) appeared to have a longer median overall survival than those with a low NK cell count (p=0.0054). A high fold change in the proportion of NK cells (>0.1957; p=0.0367) or NK cell count (>0.1045; p=0.0356) was associated with longer progression-free survival. Circulating NK cells from newly-diagnosed PCNSL demonstrated an impaired cytotoxicity capacity compared to those from patients with PCNSL in complete remission or healthy donors.

Conclusion

Our study indicated that circulating NK cells had some impact on the outcome of PCNSL.