Primary central nervous system lymphoma: status and advances in diagnosis, molecular pathogenesis, and treatment

Bruton's Tyrosine Kinase Inhibitors in Refractory or Relapsing Primary Central Nervous System Lymphoma: A Meta-analysis and Systematic Review

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is an aggressive lymphoma that primarily affects the central nervous system. Current treatments, such as surgery, chemotherapy, and whole-brain radiotherapy, often fail to achieve satisfactory results. The prognosis for patients with refractory or relapsed (R/R) PCNSL is bleak. The optimal treatment for refractory or relapsed PCNSL is poorly defined due to a limited number of studies in this setting. Bruton's tyrosine kinase (BTK) inhibitors, as part of targeted therapy regimens, have undergone testing in several clinical trials against PCNSL and have shown promising results in the treatment of R/R PCNSL. In this meta-analysis, we aim to explore and critically appraise the evidence regarding the efficacy of BTK inhibitors in the treatment of refractory or relapsed PCNSL.

METHODS

A systematic search was conducted on multiple databases including PubMed, Embase, Cochrane library, Wanfang Data Knowledge Service Platform, and CNKI, covering the period up to November 2023. The inclusion criteria for studies were patients with R/R PCNSL who received BTK inhibitors, and reported data on overall response rate (ORR) and complete remission (CR). The pooled rates were calculated using a random-effects or fixed-effects model with a double arcsine transformation, and 95% CIs were determined for all outcomes.

RESULTS

In total, 1 studies involving 185 patients were identified and included in the meta-analysis. The pooled complete remission (CR) rate of BTK inhibitors-based treatment for R/R PCNSL was found to be 50%. Subgroup analysis revealed that the CR rates for BTK inhibitor monotherapy, BTK inhibitor combined with chemotherapy, and BTK inhibitor combined with radiotherapy for R/R PCNSL were 7%, 68%, and 80%, respectively. The ORR for BTK inhibitors-based treatment for R/R PCNSL was 70%. Subgroup analysis showed that the ORR rates for BTK inhibitor monotherapy and BTK inhibitor combined with chemotherapy for R/R PCNSL were 55% and 83%, respectively. The most common adverse events (AEs) reported were hematologic AEs, including neutropenia, anemia, and thrombocytopenia. Severe nonhematologic AEs included rash, febrile neutropenia, increased levels of aspartate aminotransferase, and increased blood bilirubin.

CONCLUSIONS

BTK inhibitors can be regarded as a safe and effective treatment option for R/R PCNSL, thereby providing a potential new avenue for R/R PCNSL treatment. However, it is important to note that further large-sample prospective randomized controlled trials are needed to validate these findings and establish their wider applicability.

A comprehensive overview of diagnosis, imaging and treatment of vitreoretinal lymphoma

Vitreoretinal lymphoma (VRL) is a rare B-cell intraocular neoplasia characterized by poor long-term prognosis and lack of effective therapies. It mainly involves the vitreous humor, the retina, and the retinal pigment epithelium (RPE), although anterior segment involvement can occur. VRL is classified as a lymphoma of immune privileged sites, along with testis lymphoma and primary central nervous system lymphoma (PCNSL). VRL and PCNSL are strictly connected indeed: 80% of VRL develop PCNSL, while 20% of patients with PCNSL present VRL during natural history of lymphoma. Due to the lack of worldwide consensus about diagnosis, therapy, and follow-up timing, VRL represents one of the most challenging ocular affections.VRL commonly masquerades as a posterior uveitis, and misdiagnosis often occurs because of partial response to topical steroids. Gold standard for diagnosis is cytological analysis of vitreous humor. However, this technique lacks sensitivity and supplemental molecular analyses can improve the diagnostic process. Multimodal imaging allows ophthalmologists to empower their clinical suspicion and a comprehensive examination can highlight typical features of VRL and justify further invasive procedures.There is no consensus about VRL therapy, and none of the therapeutical scheme has demonstrated to prevent cerebral involvement and improve patient's overall survival. Intravitreal injections of chemotherapeutics drugs, ocular radiation therapy and systemic chemotherapy can be considered in the treatment of VRL. Once cerebral involvement occurs, systemic chemotherapy must be included in the treatment as a life-saving therapy. Further multicentric studies are required to find out the best treatment of patients with VRL.

Neurosurgical Management of Central Nervous System Lymphoma: Lessons Learnt from a Neuro-Oncology Multidisciplinary Team Approach

Central nervous system lymphoma (CNSL) represents one of the most aggressive forms of extranodal lymphoma. The gold standard for CNSL diagnosis remains the stereotactic biopsy, with a limited role for cytoreductive surgery that has not been supported by historical data. Our study aims to provide a comprehensive overview of neurosurgery's role in the diagnosis of systemic relapsed and primary CNSL, with an emphasis on the impact on management and survival. This is a single center retrospective cohort study with data collected between August 2012 and August 2020, including patients referred with a potential diagnosis of CNSL to the local Neuro-oncology Multidisciplinary Team (MDT). The concordance between the MDT outcome and histopathological confirmation was assessed using diagnostic statistics. A Cox regression is used for overall survival (OS) risk factor analysis, and Kaplan-Meier statistics are performed for three prognostic models. The diagnosis of lymphoma is confirmed in all cases of relapsed CNSL, and in all but two patients who underwent neurosurgery. For the relapsed CNSL group, the highest positive predictive value (PPV) is found for an MDT outcome when lymphoma had been considered as single or topmost probable diagnosis. Neuro-oncology MDT has an important role in establishing the diagnosis in CNSL, not only to plan tissue diagnosis but also to stratify the surgical candidates. The MDT outcome based on history and imaging has good predictive value for cases where lymphoma is considered the most probable diagnosis, with the best prediction for cases of relapsed CNSL, questioning the need for invasive tissue diagnosis in the latter group.

A novel inflammation-related prognostic model for predicting the overall survival of primary central nervous system lymphoma: A real-world data analysis

Background

Primary central nervous system lymphoma (PCNSL) is a type of extranodal non-Hodgkin lymphoma. Although there are widely used prognostic scores, their accuracy and practicality are insufficient. Thus, a novel prognostic prediction model was developed for risk stratification of PCNSL patients in our research.

Methods

We retrospectively collected 122 patients with PCNSL from two medical centers in China from January 2010 to June 2022. Among them, 72 patients were used as the development cohort to construct a new model, and 50 patients were used for the validation. Then, by using univariate and multivariate Cox regression analsis and Lasso analysis, the Xijing model was developed and composed of four variables, including lesion number, β2-microglobulin (β2-MG), systemic inflammation response index (SIRI) and Karnofsky performance status (KPS). Finally, we evaluated the Xijing model through internal and external validation.

Results

Compared with the original prognostic scores, the Xijing model has an overall improvement in predicting the prognosis of PCNSL according to the time-dependent area under the curve (AUC), Harrell’s concordance index (C-index), decision curve analysis (DCA), integrated discrimination improvement (IDI) and continuous net reclassification index (NRI). For overall survival (OS) and progression-free survival (PFS), the Xijing model can divide PCNSL patients into three groups, and shows more accurate stratification ability. In addition, the Xijing model can still stratify and predict prognosis similarly better in the elderly with PCNSL and subgroups received high-dose methotrexate (HD-MTX) or Bruton’s tyrosine kinase inhibitors (BTKi). Finally, external validation confirmed the above results.

Conclusions

Integrating four prognostic factors, including imaging findings, tumor burden, systemic inflammation response index, and comprehensive physical condition, we provided a novel prognostic model for PCNSL based on real-world data and evaluated its predictive capacity.

Frequent Gene Mutations and Their Possible Roles in the Pathogenesis, Treatment and Prognosis of Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma with poor prognosis. In recent years, the emergence of genetic subtypes of systematic diffuse large B-cell lymphoma has highlighted the importance of molecular genetics, but large-scale research on the molecular genetics of PCNSL is lacking. Herein, we summarize the frequent gene mutations and discuss the possible pathogenesis of PCNSL. Myeloid differentiation primary response gene 88 (MYD88) and CD79B mutations, which cause abnormal activation of noncanonical nuclear factor-κB, are prominent genetic abnormalities in PCNSL. They are considered to play a major role in the pathogenesis of PCNSL. Other genes, such as caspase recruitment domain family member 11 (CARD11), tumor necrosis factor alpha induced protein 3 (TNFAIP3), transducin (β)-like 1 X-linked receptor 1, cyclin dependent kinase inhibitor 2A, PR domain zinc finger protein 1, and proviral insertion in murine malignancies 1, are also frequently mutated. Notably, the pathogenesis of immune insufficiency-associated PCNSL is related to Epstein-Barr virus infection, and its progression may be affected by different signaling pathways. The different mutational patterns in different studies highlight the heterogeneity of PCNSL. However, existing research on the molecular genetics of PCNSL is still limited, and further research into PCNSL is required to clarify the genetic characteristics of PCNSL.

Novel insights into the biomarkers and therapies for primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive extranodal type of non-Hodgkin lymphoma. After the introduction and widespread use of high-dose-methotrexate (HD-MTX)-based polychemotherapy, treatment responses of PCNSL have been improved. However, long-term prognosis for patients who have failed first-line therapy and relapsed remains poor. Less invasive diagnostic markers, including the circulating tumor DNAs (ctDNAs), microRNAs, metabolomic markers, and other novel biomarkers, such as a proliferation inducing ligand (APRIL) and B-cell activating factor of the TNF family (BAFF), have shown potential to distinguish PCNSL at an early stage, and some of them are related with prognosis to a certain extent. Recent insights into novel therapies, including Bruton tyrosine kinase (BTK) inhibitors, immunomodulatory drugs, immune checkpoint inhibitors, PI3K/mTOR inhibitors, and chimeric antigen receptor (CAR) T cells, have revealed encouraging efficacy in treatment response, whereas the duration of response and long-term survival of patients with relapsed or refractory PCNSL (r/r PCNSL) need further improvement. In addition, the diagnostic efficiency of novel markers and the antitumor efficacy of novel therapies are needed to be assessed further in larger clinical trials. This review provides an overview of recent research on novel diagnostic markers and therapeutic strategies for PCNSL.

Diagnosis and analysis of primary central nervous system lymphoma based on MRI segmentation algorithm

Objective:

This paper summarizes the MRI imaging findings of primary central nervous system lymphoma (PCNSL) in the posterior cranial fossa to improve the accuracy of PCNSL diagnosis in the posterior cranial fossa.

Methods:

This study retrospectively analyzed the MRI imaging manifestations of 15 PCNSL posterior cranial fossa cases confirmed by puncture or surgical pathology from June 2017 to May 2018, including their occurrence sites, the number of lesions, MRI plain and enhanced manifestations, and diffusion-weighted imaging (DWI) and magnetic resonance spectroscopy. Imaging (MRS) performance.

Results:

A total of 15 cases were enrolled, including 10 cases of single lesion and five cases of multiple lesions. The total number of lesions was 25, which were in the cerebellar hemisphere and cerebellar vermis, midbrain, fourth ventricle, and pontine cerebellum. The lesions were round, irregular, nodular, patchy, with low or medium signals on T1WI, equal or slightly higher signals on T2WI, and enhanced with 25 meningiomas-like gray matter signals. All of them were significantly strengthened. “Acupoint sign” and “umbilical depression sign” were seen in eight lesions. There were 17 massive and nodular enhancements, four striped enhancements, three patchy enhancements, and one circular enhancement. five cases of DWI showed homogeneous high signal, two cases showed uneven high signal, and 3 cases showed medium signal. The ADC value of tumor parenchyma in 10 patients was (0.62±0.095)×10^-3mm²/s. MRS examination showed obvious Lip peak in two cases.

Conclusion:

PCNSL in posterior cranial fossa has certain characteristics. DWI, ADC value and MRS are helpful to improve the correct diagnosis rate of PCNSL.

Efficacy and Safety of Ibrutinib in Central Nervous System Lymphoma: A PRISMA-Compliant Single-Arm Meta-Analysis

Background

Central nervous system lymphoma (CNSL) is an aggressive lymphoma. Studies investigating primary CNSL determined that the Bruton tyrosine kinase (BTK) played an important role in pathogenesis. Ibrutinib, an oral BTK inhibitor, is a new treatment strategy for CNSL. The purpose of this meta-analysis was to clarify the effectiveness and safety of ibrutinib in the treatment of CNSL.

Methods

A systematic search of PubMed, Embase, Cochrane library, Wanfang Data Knowledge Service Platform, and China National Knowledge Infrastructure databases was conducted through to 31 October 2019. Studies involving patients with CNSL who received ibrutinib that reported the overall response (OR), complete remission (CR), and partial response (PR) were included. The random-effects or fixed-effects model with double arcsine transformation was used for the pooled rates and 95% confidence intervals (CI) were determined for all outcomes.

Results

Eight studies including 162 patients were identified and included in the meta-analysis. The pooled OR rate after treatment with ibrutinib was 69% (95% CI, 61-79%, I² = 47.57%, p = 0.06), while the pooled CR and PR was 52% (95% CI, 35-68%, I² = 74.95%, p = 0.00) and 17% (95% CI, 7-30%, I² = 67.85%, p = 0.00), respectively. Among PCNSL patients, including new diagnoses PCNSL and R/R PCNSL, the pooled OR rate was 72% (95% CI, 63-80%, I² = 49.20%, p = 0.06) while the pooled CR and PR rates were 53% (95% CI, 33-73%, I² = 75.04%, p = 0.00) and 22% (95% CI, 14-30%, I² = 46.30%, p = 0.07), respectively. Common adverse events above grade 3 included cytopenia and infections.

Conclusions

The ibrutinib-containing therapy was well tolerated and offered incremental benefit to patients with CNSL. However, randomized-controlled studies that directly compare efficacy and adverse events of ibrutinib are still needed.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020218974.

Treatment outcome in children with central nervous system-positive Burkitt lymphoma using only intrathecal and systemic chemotherapy combined with rituximab

BACKGROUND

With current chemotherapy treatment, >90% of survival has been obtained for Burkitt lymphoma (BL). In this study, the demographic characteristics and treatment outcomes are presented for 78 children in China with central nervous system-positive (CNS+) BL.

METHODS

This retrospective study consecutively enrolled 78 CNS+ BL patients in Beijing Children's Hospital (BCH) from 2007 to 2019 who received the BCH B-cell non-Hodgkin's lymphoma regimen (modified by French-American-British mature lymphoma B-cell 96 [FAB/LMB96] C1 arm ± rituximab). Clinical characteristics, methods of disease detection in the CNS, and outcomes were evaluated. Univariate and multivariate analyses were used to assess prognostic factors.

RESULTS

The median age of 65 boys and 13 girls at the time of diagnosis was 5.7 years (ranging from 1 to 14 years). Patients were followed up for a median time of 34 months (ranging from 1 to 72 months). Bone marrow invasion was found in 38 (48.7%) patients. There were 48 (61.5%), 44 (56.4%), and 25 (32%) patients with cranial nerve palsy, intracerebral mass (ICM), and para-meningeal extension, respectively. Abnormal cerebrospinal fluid (CSF) morphology and CSF immunophenotype appeared in 15 (19.2%) and 15 (19.2%) patients, respectively. There were 69 (88.5%) patients treated with chemotherapy combined with rituximab, and nine patients were treated solely with chemotherapy. Finally, five patients died of treatment-related infection, recurrence occurred for 13, and one developed a second tumor. The 3-year overall survival and event-free survival rates were 78.9% ± 4.7% and 71.4% ± 6.0%, respectively. Treatment with chemotherapy only, ICM positivity, and >4 organs involved at diagnosis were independent risk factors.

CONCLUSIONS

Rituximab combined with a modified LMB96 regimen has greatly increased the efficacy of treatment for Chinese children with CNS+ BL, and with the continuous collection of outcome data, treatment-related complications are decreasing. For further verification, a large sample multicentre randomized controlled study should be performed to explore a treatment scheme for Chinese children with even greater efficacy.