Primary central nervous system lymphoma: an update

Primary central nervous system lymphoma at the cerebellopontine angle mimicking a trigeminal schwannoma: A unique case report and literature review

Primary central nervous system lymphoma (PCNSL) is an uncommon extranodal manifestation of non-Hodgkin's lymphoma with those presenting at the cerebellopontine angle (CPA) being rare presentations with limited reported cases in the literature. We report a 60-year old female presenting with PCNSL of the left CPA radiologically mimicking a trigeminal schwannoma with corresponding clinical signs. Imaging showed a left CPA lesion that was biopsied and confirmed as diffuse large B-cell lymphoma. Given its rarity, PCNSL should be considered in the differential diagnosis for all CPA tumours.

Prognostic implications of tumor-infiltrating macrophages, M2 macrophages, regulatory T-cells, and indoleamine 2,3-dioxygenase-positive cells in primary diffuse large B-cell lymphoma of the central nervous system

Primary diffuse large B-cell lymphoma of the central nervous system (CNS-DLBCL) is an aggressive disease with a poor prognosis. The status of the tumor immune microenvironment in CNS-DLBCL remains unclear. We investigated the prognostic implications of tumor-associated macrophages (TAMs), regulatory T-cells (Tregs), and indoleamine 2,3-dioxygenase (IDO)⁺ cells in primary CNS-DLBCL (n = 114) by immunohistochemical analysis. The numbers of tumor-infiltrating immune cells, including CD68⁺ TAMs, CD163⁺ or CD204⁺ M2 macrophages, FOXP3⁺ Tregs, and IDO⁺ cells were all significantly lower in CNS-DLBCL versus systemic DLBCL (n = 165; all P < 0.001), but with little difference in the ratio of CD163⁺/CD68⁺ or CD204⁺/CD68⁺ cells. An increase in CD68⁺ cell numbers was significantly associated with prolonged progression-free survival (PFS) and overall survival in patients with CNS-DLBCL (P = 0.004 and 0.021, respectively). In contrast, an increase in CD204⁺ cell numbers or a higher ratio of CD204⁺/CD68⁺ cells was related to a shorter PFS (P = 0.020 and 0.063, respectively). An increase in IDO⁺ cell numbers was associated with a significantly longer PFS (P = 0.019). In combination, the status of low IDO⁺ cell numbers combined with low CD68⁺ cell numbers, high CD204⁺ cell numbers, or a high CD204⁺/CD68⁺ cell ratio all predicted poor PFS in multivariate analyses. This study showed that an increase in CD204⁺ cell numbers, suggestive of M2 macrophages, was associated with poor clinical outcome in CNS-DLBCL, whereas increased CD68⁺ or IDO⁺ cell numbers were related to a favorable prognosis. The analysis of tumor-infiltrating immune cells could help in predicting the prognosis of CNS-DLBCL patients and determining therapeutic strategies targeting tumor microenvironment.

Primary Central Nervous System Anaplastic Large T-cell Lymphoma

INTRODUCTION

Primary central nervous system lymphoma (PCNSL) of T-cell origin is an exceptionally rare, highly malignant intracranial neoplasm. Although such a tumor typically presents with a focal mass lesion.

CASE REPORT

Past medical history of a 26-year-old male patient with a PCNS lymphoma of T-cell origin was not suggestive of intracranial pathology or any disorder of other organs and organic systems. To achieve a gross total tumor resection, surgery was performed via osteoplastic craniotomy using the left frontal transcortical transventricular approach. Histological and immunohistochemical analyses of the tissue removed described tumor as anaplastic large cell lymphoma of T-cells (T-ALCL). Postoperative and neurological recovery was complete, while control imaging of the brain showed no signs of residual tumor at a six-month follow-up. The patient, who did not appear immunocompromized, was referred to a hematologist and an oncologist where corticosteroids, the particular chemotherapeutic protocol and irradiation therapy were applied.

CONCLUSION

Since PCNS lymphoma is a potentially curable brain tumor, we believe that proper selection of the management options, including early radical tumor resection for solitary PCNS lymphoma, may be proposed as a major treatment of such a tumor in selected patients, resulting in a satisfactory outcome.

Primary diffuse large B-cell lymphoma of the central nervous system: A case report and literature review

The present study reports the clinical diagnosis and management of a patient with primary diffuse large B-cell lymphoma (Bcl) of the central nervous system (CNS). Making an early diagnosis of primary diffuse large Bcl is challenging due to the variable and complicated clinical manifestations of the disease. The relevant literature was reviewed, and high-dose methotrexate, whole brain radiotherapy and highly active antiretroviral therapy was recommended for the patient. The present study elucidates the role of positron emission tomography-computed tomography scans for the diagnosis and management of primary diffuse large Bcl of the CNS, and demonstrates the importance of resection surgery in the management of the disease. Specifically, the present study proposes that resection surgery may be applied in the early stages of disease for patients with a single occupied lesion and increased intracranial pressure.

A rare case of nonenhancing primary central nervous system lymphoma mimic multiple sclerosis

Primary central nervous system lymphoma (PCNSL) is reported to have increased in the last decades. Early diagnosis is crucial for proper management of this tumor. We report a case of a 48-year-old man who was initially diagnosed with multiple sclerosis. Magnetic resonance imaging of the brain revealed multiple lesions with hypersignals in the bilateral basal ganglia and brain stem in T2-weighted image and non-enhancement, while positron emission tomography showed a low uptake of ¹⁸F-fluorodeoxyglucose in the affected brain, indicative of demyelination. However, this individual was correctly diagnosed with PCNSL after biopsy and further histological analysis. Primary central nervous system lymphoma must be considered even when nonenhancing, diffuse lesions are seen on MRI. A visible tumor on imaging is essential to ensure an early brain biopsy and histological diagnosis.

Primary T cell central nervous system lymphoblastic lymphoma in a child: case report and literature review

PURPOSE

Primary central nervous system lymphoma (PCNSL) of T cell origin is rare in pediatric patients. We report a case of T cell PCNSL in a 12-year-old boy and review the literature to highlight the importance of brain biopsy to definitively establish the diagnosis when PCNSL is suspected.

CASE REPORT

A 12-year-old boy presented with worsening left-sided weakness, nausea, vomiting, headache, blurred vision, and diplopia. Magnetic resonance imaging revealed right parietal gyral thickening with faint meningeal contrast enhancement. No clear diagnosis was identified after serum testing, cerebrospinal fluid analysis, and cerebral angiography. To establish the diagnosis definitively, a right craniotomy and open, frameless stereotactic biopsy were performed, which yielded the diagnosis of lymphoblastic T cell lymphoma.

CONCLUSIONS

PCNSL of T cell origin in children remains poorly studied, with only 18 detailed cases reported over the last three decades, including this case. Establishing a definitive diagnosis of PCNSL is challenging, and a brain biopsy is often required to obtain enough tissue for pathological analysis. Increasing awareness and identification of children diagnosed with T cell PCNSL is needed to better understand the molecular biology of this disease and develop more standardized treatment regimens.

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 central nervous system lymphoma

INTRODUCTION

Primary central nervous system lymphoma is a rare subtype of extranodal non-Hodgkin lymphoma that accounts for 4% of central nervous system tumours.

PATIENTS AND METHODS

Retrospective review of 24 patients diagnosed with primary central nervous system lymphoma between 1990 and 2010. All patients were diagnosed using magnetic resonance imaging and the diagnosis was confirmed surgically.

RESULTS

Of the 24 patients analysed, all except 4 were immunocompetent. Median age at diagnosis was 59.3 years (range 13-79) and the sex ratio (male to female) was 1:1.1. Cognitive decline (in 33.4%) and headache (in 25%) were the most common complaints. Diagnosis was performed In 13 cases (54%) following craniotomy and in the other 11 cases (46%) after stereotactic biopsy. Breakdown by pathology was as follows: 22 cases of B-cell lymphoma (91.6%), 1 case of anaplastic large-cell lymphoma, and 1 case of T-cell lymphoma. Mean survival time was 12.8 months with an overall 1-year survival rate of 37.5%.

CONCLUSIONS

Primary central nervous system lymphoma often presents in the sixth decade with cognitive decline, headache, and focal neurological deficits. A single intracranial lesion was present in 75% of the patients (18 cases), and the remaining 25% (6 cases) had between 2 and 4 lesions. Preoperative clinical status was the most important factor determining prognosis.

[Management of primary central nervous system lymphoma]

Primary CNS lymphoma is the malignant brain tumor whose prognosis has improved the most the two past decades. The majority of the patients achieve a complete remission with treatment and a substantial minority may hope to be cured. The treatment includes high-dose methotrexate polychemotherapy combined or not with whole brain radiotherapy (WBRT). Elderly patients who are exposed to a high risk of treatment induced neurotoxicity need a specific management avoiding or defering WBRT. In young patients, the main questions concerning the treatment are the role of consolidation WBRT and intensive chemotherapy with peripheral blood stem cell rescue in the initial treatment of PCNSL. As recently shown, national and international collaborative efforts make now possible randomized trials for this rare disease, which would contribute to better define the treatment strategy. New insights in PCNSL tumorigenesis would help to better understand the heterogeneity of outcome and to develop efficient targeted therapies.

Prophylactic intrathecal chemotherapy in primary CNS lymphoma

The role of prophylactic intrathecal chemotherapy in the treatment of primary central nervous system lymphoma remains controversial. We report a retrospective single center study of a cohort of 69 patients with primary central nervous system lymphoma who had been treated with a regimen that combined high intravenous doses of Methotrexate, CCNU, procarbazine and methylprednisolone. Before 2000, patients systematically received intrathecal prophylaxis including Methotrexate, cytarabine, and hydrocortisone delivered either by intraventricular or lumbar injection along with the systemic chemotherapy (group A, n = 39). After this date, the procedure was changed and intrathecal chemotherapy was withdrawn from the protocol (group B, n = 30). The median age and Karnofsky index were comparable in both groups. At the time of analysis, we found no significant difference between patients with and without intrathecal prophylaxis in terms of objective response rate, patterns of relapse, progression-free survival or overall survival. In our study, intrathecal prophylaxis withdrawal from a high dose intravenous Methotrexate-based chemotherapy regimen did not influence disease control and outcome of primary central nervous system lymphoma. Further studies prospectively investigating the role of intrathecal chemoprophylaxis are warranted for this disease.

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.

Chemotherapy in newly diagnosed primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) accounts for only 3% of brain tumors. It can involve the brain parenchyma, leptomeninges, eyes and the spinal cord. Unlike systemic lymphoma, durable remissions remain uncommon. Although phase III trials in this rare disease are difficult to perform, many phase II trials have attempted to define standards of care. Treatment modalities for patients with newly diagnosed PCNSL include radiation and/or chemotherapy. While the role of radiation therapy for initial management of PCNSL is controversial, clinical trials will attempt to improve the therapeutic index of this modality. Routes of chemotherapy administration include intravenous, intraocular, intraventricular or intra-arterial. Multiple trials have outlined different methotrexate-based chemotherapy regimens and have used local techniques to improve drug delivery. A major challenge in the management of patients with PCNSL remains the delivery of aggressive treatment with preservation of neurocognitive function. Because PCNSL is rare, it is important to perform multicenter clinical trials and to incorporate detailed measurements of long-term toxicities. In this review we focus on different chemotherapeutic approaches for immunocompetent patients with newly diagnosed PCNSL and discuss the role of local drug delivery in addition to systemic therapy. We also address the neurocognitive toxicity of treatment.