Current Management of Primary Central Nervous System Lymphoma

Assessment of therapeutic effect of CD20-targeted immunoliposome in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a form of extranodal non-Hodgkin's B-cell lymphoma limited to the CNS. The treatment of PCNSL is ineffective partly due to the blood-brain barrier (BBB) restriction of delivery of many drugs including anti-CD20 (Rituximab; RTX) which is a standard treatment for systemic B-cell lymphomas. In this study, liposome with tween-80 surface modification was fabricated and conjugated with RTX for enhancing BBB penetration to target lymphoma cells in the CNS. Physicochemical characterizations of Lip/RTX were performed and spherical shape liposomes with narrow size distribution were demonstrated by TEM. An average diameter of Lip/RTX was 168.57 ± 1.57 nm with the percentage of RTX conjugation at 90.94. Cell internalization monitored by flow cytometry confirmed that conjugation of RTX promoted liposome entry into Raji cells expressing CD20. Antitumor activity of Lip/RTX was comparable to free RTX indicating that RTX moieties on liposome remained their therapeutic function. In addition, Lip/RTX inhibited tumor aggressiveness by limiting cell migration and invasion. Systemic administration of Lip/RTX significantly prolonged survival of mice harboring intracranial lymphoma xenografts. Taken together, Lip/RTX presents a new potential treatment for patients with PCNSL.

Different imaging patterns of PCNSL and IVL: a case report

Background

Primary central nervous system lymphoma (PCNSL) is a rare, malignant, non-Hodgkin’s lymphoma of the brain, leptomeninges, and rarely the spinal cord. PCNSL has characteristic magnetic resonance imaging (MRI) findings, and effective treatment strategies are available. It is characterized predominately by neurological symptoms, which are caused by tumor infiltration into the nervous system as well as ischemia. Chemotherapy is an effective treatment, if started prior to the ischemic damage.

Case presentation

A 62-year-old male patient with PCNSL presented with altered mental status. The initial brain MRI revealed high signal intensity on the T2-weighted images (T2WIs) of the putamen area of the right basal ganglia, and the clinical symptoms improved after steroid administration. However, the symptoms were later deteriorated, we considered the possibility of autoimmune encephalitis and, consequently, conducted an immunomodulatory therapy. In a follow-up brain MRI, enlargement lesions of T2WI in basal ganglia and pons were simultaneously enhanced. Subsequently, the patient’s mental status deteriorated to a semi-coma and PCNSL was diagnosed after a surgical biopsy. Chemotherapy was started immediately; however, the patient died.

Conclusions

Effective treatments are available for PCNSL and intravascular lymphoma; thus, their prognosis is generally good if they are diagnosed early. Herein, we report the case of a patient suspected with autoimmune encephalitis after brain MRI and treated with immunomodulation therapy. However, PCNSL was confirmed by a surgical biopsy. It is, therefore recommended to consider lymphoma in patients with neurological symptoms that are difficult to localize and rapidly progressive enhancing lesions showing a mass effect on brain MRI.

Diagnostic performance of DWI for differentiating primary central nervous system lymphoma from glioblastoma: a systematic review and meta-analysis

OBJECTIVE

The purpose of this meta-analysis was to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) for differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM).

MATERIALS AND METHODS

A thorough search of the databases including PubMed, EMBASE, and Cochrane Library was carried out and the data acquired were up to November 1, 2017. The quality of the studies involved was evaluated using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies, revised version). Multiple analytic values including sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the summary receiver operating characteristic (SROC) curve were calculated and pooled for the statistical analysis. The subgroup analysis was also performed to explore the heterogeneity.

RESULTS

Eight retrospective studies (461 patients with 461 lesions) were included. The pooled SEN, SPE, PLR, NLR, and DOR with 95% confidence interval (CI) were 0.82 [95% CI 0.70-0.90], 0.84 [95% CI 0.75-0.90], 4.96 [95% CI 3.20-7.69], 0.22 [95% CI 0.13-0.37], and 22.85 [95% CI 10.42-50.11], respectively. The area under the curve (AUC) given by SROC curve was 0.90 [95% CI 0.87-0.92]. The subgroup analysis indicated the slice thickness of the images (> 3 mm versus ≤ 3 mm) was a significant factor affecting the heterogeneity. No existence of significant publication bias was confirmed with Deeks' test.

CONCLUSIONS

DWI showed moderate diagnostic performance for differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM). Moreover, it is of clinical significance using DWI combined with conventional MRI to differentiate PCNSL from GBM.

Differential diagnosis of posterior fossa brain tumors: Multiple discriminant analysis of Tl-SPECT and FDG-PET

This study investigated the combined capability of thallium-201 (Tl)-SPECT and fluorine-18-fluoro-deoxy-glucose (FDG)-PET for differential diagnosis of posterior fossa brain tumors using multiple discriminant analysis.This retrospective study was conducted under approval of the institutional review board. In the hospital information system, 27 patients with posterior fossa intra-axial tumor between January 2009 and June 2015 were enrolled and grouped as the following 7 entities: low grade glioma (LGG) 6, anaplastic astrocytoma (AA) 2, glioblastoma (GBM) 3, medulloblastoma (MB) 3, hemangioblastoma (HB) 6, metastatic tumor (Mets) 3, and malignant lymphoma (ML) 4. Tl and FDG uptakes were measured at the tumors and control areas, and several indexes were derived. Using indexes selected by the stepwise method, discriminant analysis was conducted with leave-one-out cross-validation.The predicted accuracy for tumor classification was 70.4% at initial analysis and 55.6% at cross-validation to differentiate 7 tumor entities. HB, LGG, and ML were well-discriminated, but AA was located next to LGG. GBM, MB, and Mets largely overlapped and could not be well distinguished even applying multiple discriminant analysis. Correct classification in the original and cross-validation analyses was 44.4% and 33.3% for Tl-SPECT and 55.6% and 48.1% for FDG-PET.

Neuroimaging in Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare aggressive high-grade type of extranodal lymphoma. PCNSL can have a variable imaging appearance and can mimic other brain disorders such as encephalitis, demyelination, and stroke. In addition to PCNSL, the CNS can be secondarily involved by systemic lymphoma. Computed tomography and conventional MRI are the initial imaging modalities to evaluate these lesions. Recently, however, advanced MRI techniques are more often used in an effort to narrow the differential diagnosis and potentially inform diagnostic and therapeutic decisions.

Value of pretherapeutic DWI in evaluating prognosis and therapeutic effect in immunocompetent patients with primary central nervous system lymphoma given high-dose methotrexate-based chemotherapy: ADC-based assessment

AIM

To investigate apparent diffusion coefficient (ADC) as a prognostic indicator in primary central nervous system lymphoma (PCNSL) by analysing patient clinical characteristics and pretherapeutic diffusion-weighted imaging (DWI).

MATERIALS AND METHODS

Clinical characteristics and pretherapeutic DWI were studied retrospectively in 28 patients receiving high-dose methotrexate (HD-MTX)-based chemotherapy. Mean (ADCmean), 95th percentile (ADC95%), and 5th percentile (ADC5%) ADC values of the enhancing tumour volume were measured. The influence of prognostic parameters on progression-free survival (PFS) was investigated by log-rank test and Cox regression analysis. Correlations between the variables and PFS or the level of Ki-67 expression were analysed. ADC and clinical features were analysed using an independent sample t-test between the complete response (CRi) and partial response (PRi) groups after initial four cycles of chemotherapy. Receiver operating characteristic (ROC) curves were constructed using ADC parameters.

RESULTS

Patients with CRi, lower Ki-67 level, higher Karnofsky performance status (KPS), ADC5%, or ADCmean showed better PFS. The level of Ki-67 expression and ADC5% were independent risk factors. There was a positive correlation between KPS, ADC5%, and PFS, and negative correlation between ADC5%, PFS, and the level of Ki-67 expression. There was a significant difference for PFS, KPS, ADCmean, and ADC5% between CRi and non-CRi; however, ADC5% outperformed ADCmean because the area under the ROC curve (AUC) using ADC5% (0.983) was higher than the AUC using ADCmean (0.822).

CONCLUSION

ADC measurements, especially ADC5%, are useful predictors for PFS and response to HD-MTX in PCNSL.

Inflammatory Demyelinating Brain Lesions Heralding Primary CNS Lymphoma

Brain biopsy plays a crucial role in the exploration of suspect white matter lesions in the differential diagnosis of primary central nervous system lymphoma (PCNSL) and inflammatory demyelination. We present the case of a previously healthy, immunocompetent woman, aged fifty-nine, who developed a histologically confirmed demyelinating white matter lesion months prior to the manifestation of a PCNSL. Similar cases of “sentinel lesions” preceding a PCNSL have been reported. In a literature review, we compared the diagnostic features that may be useful to differentiate a PCNSL from inflammatory demyelinating disease in older age. We conclude that the occurrence of large, contrast-enhancing cerebral lesions in older patients with a relapsing-remitting disease course and steroid-resistant vision disorders should lead to the consideration of a PCNSL.

Low-dose whole brain radiotherapy with tumor bed boost after methotrexate-based chemotherapy for primary central nervous system lymphoma

PURPOSE

The purpose of this study is to evaluate the outcome of low-dose whole brain radiotherapy (WBRT) with tumor bed boost after methotrexate-based chemotherapy in the management of primary central nervous system lymphoma (PCNSL).

MATERIALS AND METHODS

We retrospectively analyzed 64 patients with pathologically proven PCNSL between 2000 and 2011. Methotrexate-based chemotherapy with a median of five cycles was followed by radiotherapy to the whole brain and to the initial tumor bed. The median dose to the whole brain and to the tumor bed was 27 Gy (range, 18 to 36 Gy) and 50.4 Gy (range, 45 to 54 Gy), respectively.

RESULTS

With a median follow-up period of 27 months, 55 patients (85.9%) achieved complete response (CR). The 5-year overall survival (OS) and progression-free survival (PFS) rates were 52.6% and 39.3%, respectively. In univariate analysis, factors associated with OS were age, performance status, involvement of deep structure, and CR to sequential chemoradiotherapy (CRT). These variables remained as significant factors for OS in multivariate analysis. CR to sequential CRT was the only positive factor associated with PFS (p=0.009). Neurologic toxicity was more common in elderly patients older than 60 years (p=0.025).

CONCLUSION

Low-dose WBRT with tumor bed boost after methotrexate-based chemotherapy might be an effective method for management of PCNSL.

The role of additional radiotherapy for primary central nervous system lymphoma

BACKGROUND

Prior to the introduction of the chemotherapeutic agent methotrexate, radiotherapy was the sole, first-line option for the treatment of individuals with primary central nervous system lymphoma (PCNSL), Now that methotrexate is available, the role of radiotherapy in the treatment of PCNSL has been called into question. Although various studies suggest promising results with regard to overall and progression-free survival with the use of chemotherapeutic regimens alone as well as in combination with radiotherapy, no evidence-based standard regimen has yet been defined.

OBJECTIVES

The objective of this review was to assess and summarise the evidence available regarding the efficacy and tolerability of radiotherapy in addition to chemotherapy in the treatment of immunocompetent individuals with PCNSL.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (issue 01.2014), MEDLINE from January 1950 to February 2014 and conference proceedings from 2005 to 2013. 

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing chemotherapy plus radiotherapy with chemotherapy alone in individuals with PCNSL. Outcomes defined in this review were overall survival, progression-free survival, response to treatment, adverse events, treatment related mortality and quality of life. We excluded trials in which the chemotherapy regimen differed between treatment arms, trials in which fewer than 80% of participants had PCNSL or those recruiting immunocompromised individuals with PCNSL.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of the search strategies for eligibility for this review. Both assessed risk of bias. Where relevant data was unavailable, we contacted the investigator by email.

MAIN RESULTS

Of the 556 potentially relevant studies only two met the inclusion criteria. One of those was excluded as the trial was abandoned prematurely and reported only preliminary results. The only analysed trial enrolled 551 participants receiving first-line chemotherapy (methotrexate) followed by whole brain radiotherapy (WBR) or receiving chemotherapy only (methotrexate followed by cytarabine in case of incomplete response). In this non-inferiority trial, the intention-to-treat (ITT) population consisted of 411 participants and the per-protocol (PP) population of 318 participants. We judged the potential for risk of bias in this open-label study as moderate.The estimated effect of chemotherapy plus WBR on survival was similar to that with chemotherapy alone but due to a wide CI we could not rule out the superiority of either therapy. This applied to both the ITT population (HR 1.01, 95% CI 0.79 to 1.30; P = 0.94) and the PP population (HR 1.06, 95% CI 0.80 to 1.40; P = 0.71) (moderate-quality evidence). Due to the low number of participants and a risk of detection bias we found low-quality evidence for an improvement in progression-free survival in participants in the ITT population receiving WBR in addition to chemotherapy (HR 0.79, 95% CI 0.63 to 0.99; P = 0.041). An improvement in PFS was also observed with WBR plus chemotherapy in participants in the PP population, but the CI was slightly wider and the result not significant (HR 0.82,95% CI 0.64 to 1.07; P = 0.14). Treatment-related mortality and health-related quality of life were not evaluated. Treatment-related neurotoxicity was assessed clinically in 79 participants, revealing signs of neurotoxicity in 49% of those receiving chemotherapy plus radiotherapy and in 26% of those receiving chemotherapy only (RR 1.85, 95% CI 0.98 to 3.48; P = 0.054) (very-low-quality evidence).

AUTHORS' CONCLUSIONS

In summary, the currently available evidence (one RCT) is not sufficient to conclude that WBR plus chemotherapy and chemotherapy alone have similar effects on overall survival in people with PCNSL. The findings suggest that the addition of radiotherapy (WBR) to chemotherapy may increase progression-free survival, but may also increase the incidence of neurotoxicity compared to chemotherapy only (methotrexate monotherapy). As the role of chemoradiotherapy in the treatment of PCNSL remains unclear, further prospective, randomised trials are needed before definitive conclusions can be drawn.

Primary CNS lymphoma treated with radiotherapy in Japan: a survey of patients treated in 2005-2009 and a comparison with those treated in 1985-2004

BACKGROUND

The aim of our study was to analyze changes over time in the characteristics, treatment, and outcome of patients with primary central nervous system lymphoma (PCNSL).

METHODS

Data on 315 patients with histologically proven PCNSL undergoing radiotherapy between 2005 and 2009 were collected from 20 Japanese institutions using a questionnaire. These data were then compared with data on 273 patients treated during the period 1995-2004 and those on 466 patients treated during the period 1985-1994.

RESULTS

In terms of patient and tumor characteristics, we found a significant increase in mean patient age in the 2005-2009 period compared to the 1985-2004 period (63 vs. 58-59 years, respectively) and in the percentage of patients with better performance status (PS) during the 2005-2009 period compared with the 1995-2004 period (World Health Organization PS 0-2: 73 vs. 65 %, respectively). Regarding treatment, relative to the 1995-2004 period, significant changes in the 2005-2009 period were (1) decreased rate of attempting tumor resection (23 vs. 44 %); (2) increased use of chemotherapy (78 vs. 68 %), and (3) increased use of methotrexate (MTX)-containing regimens (84 vs. 53 %). The 5-year overall survival rates were 15.3, 30.1, and 36.5 % for patients seen during the 1985-1994, 1995-2004, and 2005-2009 periods, respectively, but relapse-free survival did not improve between the 1995-2004 and 2005-2009 periods (26.7 vs. 25.7 % at 5 years, respectively). Patients receiving MTX-containing chemotherapy had 5-year survival rates of 19, 50, and 44 % during these three periods, respectively.

CONCLUSIONS

Although patient backgrounds differed among the study periods, recent trends were a high patient age, better PS, avoidance of extensive tumor resection, more frequent use of chemotherapy, and improved survival. The recent improvement in survival may be due to improvements in second-line treatment and supportive care.

Primary central nervous system lymphoma: a clinicopathological and cytomorpholgical study from a tertiary care centre in Chennai, India

BACKGROUND

The aim of this study was to analyze the clinicopathological and immunohistochemical features of primary central nervous system lymphoma (PCNSL) cases occurring in Indian patients and also study the utility of the crush smear preparation in intraoperative diagnosis.

MATERIALS AND METHODS

The immune status, clinical, radiological details, immunohistochemical profile, histopathological findings and cytological features in smear preparation of 32 cases of PCNSL were analyzed. Patients with systemic NHL and skull-base lymphomas were excluded.

RESULTS

The mean age of our patients was 52 years with a male: female ratio 1:1. A periventricular location was found in 62.5% of patients. None of our PCNSL cases were associated with AIDS. All cases except one were diffuse large B-cell lymphomas. Intraoperative diagnosis using crush smears allowed correct prediction in 93% of cases.

CONCLUSIONS

Our study shows that PCNSL is seen predominantly in immunocompetent patients in India .The age of presentation is relatively young as compared to the West. Our study also stresses the utility of crush smear preparation in establishing an intraoperative diagnosis.

Role of neurosurgery and radiation therapy in the management of brain tumors

In the United States, approximately 65,000 people are diagnosed with primary brain tumors each year, with an incidence of 19.3 cases per 100,000 person-years. These numbers represent a wide spectrum of disease, from benign to malignant, and prognosis varies widely based on disease. Treatment of primary brain tumors most often uses a combination of surgery and radiation. However, over the past several generations, technological advancements have significantly altered the treatment paradigm. This article reviews the current role of neurosurgery and radiation therapy in the management of primary brain tumors.

Immune adaptive microenvironment profiles in intracerebral and intrasplenic lymphomas share common characteristics

A large body of evidence indicates that the immune microenvironment controls tumour development. Primary central nervous system lymphomas (PCNSL) are aggressive tumours growing in the central nervous system (CNS). To evaluate the role and characteristics of this immune-privileged site in anti-tumour defences, we compared the cellular and molecular immune microenvironments of growing murine lymphoma B cells injected into the brain or the spleen. In the brain, immune cells, including dendritic cells and T lymphocytes with a large proportion of CD4(+) forkhead box P3 (FoxP3(+)) regulatory T cells, rapidly infiltrated the tumour microenvironment. These populations also increased in number in the spleen. The T cell cytokine profiles in tumour-bearing mice were similar in the two sites, with predominant T helper type 1 (Th1)/Th17 polarization after polyclonal stimulation, although some interleukin (IL)-4 could also be found. We demonstrated that these T cells have anti-tumour activity in the CNS, although less than in the spleen: nude mice that received lymphoma cells intracerebrally died significantly earlier than immunocompetent animals. These results demonstrate that the brain is able to recruit all the major actors to mount a specific anti-tumour immune response against lymphoma.