Impact of histologic subtypes and treatment modality among patients with primary central nervous system lymphoma: a SEER database analysis

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.

Primary central nervous system marginal zone lymphoma

Marginal zone lymphoma (MZL) is the most common indolent lymphoma primarily arising in the central nervous system (CNS). To date, 207 cases of primary CNS MZL (PCNSMZL) were published, mostly as single case reports or small case series. It most commonly presents as extra-axial dural-based masses, more frequently in middle-aged women, displaying an insidious onset, with a long history of symptoms preceding the diagnosis. PCNSMZL can be radiographically mistaken for meningioma. PCNSMZL consists of CD20+ , CD3- small B lymphocytes with varying degrees of plasmacytic differentiation and low proliferation index. Trisomy 3, but not MALT1 or IgH translocation, is a common genetic abnormality. Other recurrent genetic abnormalities involve TNFAIP3 and NOTCH2. Ethiopathogenesis was poorly investigated. Due to its rarity, standard of care remains to be defined; it exhibits an excellent prognosis after varied treatments, such as surgery, radiotherapy, chemotherapy or their combinations. Nevertheless, each treatment should be considered after an accurate analysis of overtreatment risk. Short follow-up is a major limitation in reported PCNSMZL cases, which restrains our knowledge on long-term results and iatrogenic sequels. This review was focussed on presentation, differential diagnoses, pathological findings, treatment options and clinical outcomes of PCNSMZL; recommendations for best clinical practice are provided.

Lymphoma of the central nervous system originating from the septum pellucidum region: Two case reports with literature review

RATIONALE

Non-Hodgkin lymphoma affecting the brain, eyes, and cerebrospinal fluid without systemic spread is known as primary central nervous system lymphoma (PCNSL). While intracerebroventricular PCNSL is commonly found in the lateral ventricles and the third and fourth ventricles, the occurrence of PCNSL originating from the septum pellucidum is extremely rare.

PATIENT CONCERNS

Two patients presented with recent memory loss and high cranial pressure.

DIAGNOSES

Magnetic resonance imaging revealed a clear enhancing lesion in the septum pellucidum region. Pathological examination confirmed that both cases were primary large B-cell lymphoma GCB (germinal center B-cell-like) subtypes located in an "immune-privileged" area.

INTERVENTIONS

Both patients underwent total tumor resection, and the procedures were successfully completed without surgical complications.

OUTCOMES

Over a 1-year period, treatment included four cycles of high-dose methotrexate combined with temozolomide. During the follow-up period (19-23 months), no recurrence of the lymphoma was observed.

LESSONS

In cases of PCNSL in the septum pellucidum, it is crucial to consider it as a potential differential diagnosis for intraventricular tumors. Surgical interventions should focus on maximizing tumor resection while ensuring the protection of critical structures like the fornix and peripheral neural components. The role of surgery compared to biopsy, as well as the long-term complications, necessitates extended follow-up. Additionally, an individualized treatment approach, considering factors such as age, Karnofsky performance score, and organ function assessment, can lead to positive outcomes.

Primary Dural Mucosa-associated Lymphoid Tissue Lymphoma Mimicking Falx Meningioma: A Case Report

An 85-year-old woman presented with ataxia and deterioration of cognitive functions. She had no history of autoimmune diseases or viral infections. Magnetic resonance imaging showed a solitary mass lesion at the cerebral falx on contrast-enhanced T1-weighted imaging. Gross total resection of the lesion involving the dura mater was performed by bifrontal craniotomy. Histological examination showed diffuse infiltration of small lymphocytes and plasma cells. There was also some proliferation of large lymphocytes with folded nuclei, high-density chromatin, and inconspicuous nucleoli. The large atypical B lymphocytes did not demonstrate diffuse dense sheet findings. Meningothelial components were not detected. Immunohistochemistry was positive for pan B-cell antigens. The analysis of the kappa/lambda ratio indicated kappa immunoglobulin light chain-restricted B-cell proliferation. The final histopathological diagnosis was mucosa-associated lymphoid tissue lymphoma. Systemic screening examinations were then performed. Histological findings of the bone marrow showed normal findings without atypical lymphocytes. A chromosomal study of the bone marrow showed 46, XX. 18F fluoro-2-deoxyglucose positron emission tomography showed high accumulations at the left pterygoid muscle and the right transverse processes of the thoracic vertebrae, and mild accumulation at the right ilium bone, which indicated disseminated lesions. One year later, thickening of the dura mater was detected. Therefore, gamma knife surgery was performed. Two years later, she was alive without neurological deterioration, and magnetic resonance imaging showed no evidence of recurrence.

Diffuse large B-cell lymphoma: An uncommon diagnosis at the cerebellopontine angle - A case report

Primary central nervous system lymphoma (PCNSL), a rare variant of extranodal non-Hodgkin's lymphoma, has shown an increased incidence over the last 3-4 decades in both immunocompromised and immunocompetent individuals. Only <20 cases of cerebellopontine (CP) angle lymphoma have been reported so far in the literature. Hereby, we report a case of primary lymphoma of the CP angle mimicking vestibular schwannoma and other common pathologies at the CP angle. Hence, while evaluating a lesion at CP angle, PCNSL should always be considered in the differential diagnosis.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare extranodal lymphomatous malignancy that affects the brain, spinal cord, leptomeninges, or vitreoretinal space, without evidence of systemic involvement. The diagnosis of PCNSL requires a high level of suspicion because clinical presentation varies depending upon involved structures. Initiation of treatment is time sensitive for optimal neurologic recovery and disease control. In general, the prognosis of PCNSL has improved significantly over the past few decades, largely as a result of the introduction and widespread use of high-dose methotrexate (MTX) chemotherapy, which is considered the backbone of first-line polychemotherapy treatment. Upon completion of MTX-based treatment, a consolidation strategy is often required to prolong duration of response. Consolidation can consist of radiation, maintenance therapy, nonmyeloablative chemotherapy, or myeloablative treatment followed by autologous stem cell transplant. Unfortunately, even with consolidation, relapse is common, and 5-year survival rates stand at only 30% to 40%. Novel insights into the pathophysiology of PCNSL have identified key mechanisms in tumor pathogenesis, including activation of the B-cell receptor pathway, immune evasion, and a suppressed tumor immune microenvironment. These insights have led to the identification of novel small molecules targeting these aberrant pathways. The Bruton tyrosine kinase inhibitor ibrutinib and immunomodulatory drugs (lenalidomide or pomalidomide) have shown promising clinical response rates for relapsed/refractory PCNSL and are increasingly used for the treatment of recurrent disease. This review provides a discussion of the clinical presentation of PCNSL, the approach to work-up and staging, and an overview of recent advancements in the understanding of the pathophysiology and current treatment strategies for immunocompetent patients.

Chemotherapy is an efficient treatment in primary CNS MALT lymphoma

BACKGROUND

Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was to better describe these tumors, their management and their long-term prognosis.

METHODS

Patients with primary CNS MALT lymphoma (PCNSML) were retrospectively selected from the database on PCNSL of the Pitié-Salpêtrière Hospital.

RESULTS

Of 662 PCNSL, 11 (1.7%) PCNSML (9 females and 2 males, median age: 56 years) were selected. The median time from first symptoms to diagnosis was 13 months. Location was dural in 8 cases and parenchymal in 3 cases. The disease was multifocal/diffuse in 7 cases. In first line, all patients received chemotherapy (high-dose methotrexate (HD-MTX) based chemotherapy (n = 4) and non-HD-MTX-based chemotherapy (n = 7)), preceded by surgery in 4 cases. None received radiotherapy. According to the IPCG (International PCNSL Collaborative Group) criteria, the overall response rate was 7/11 (64%). At latest news, 5 patients had persistent contrast enhancement, stable with no treatment since a median of 57 months, raising the question of complete response despite persisting contrast enhancement. No patient developed neurotoxicity except for one patient who subsequently received radiotherapy. The median follow-up was 109 months. The median progression-free survival was 78.0 months and the 10-year overall survival rate was 90%.

CONCLUSION

This is the largest series demonstrating that chemotherapy is an efficient treatment in PCNSML, with an excellent long-term outcome and the absence of neurotoxicity, and calling into question the relevance of the IPCG criteria for the evaluation of response.

Rare central nervous system lymphomas

Central nervous system (CNS) lymphomas are rare malignancies characterised by lymphoid infiltration into the brain, spinal cord, cranial nerves, meninges and/or eyes in the presence or absence of previous or concurrent systemic disease. Most CNS lymphomas are of the diffuse large B-cell lymphoma (DLBCL) subtype for which treatment strategies, particularly the use of high-dose methotrexate-based protocols and consolidation with autologous stem cell transplantation, are well established. Other histopathological subtypes of CNS lymphoma are comparatively less common with published data on these rare lymphomas dominated by smaller case series and retrospective reports. Consequently, there exists little clinical consensus on the optimal methods to diagnose and manage these clinically and biologically heterogeneous CNS lymphomas. In this review article, we focus on rarer CNS lymphomas, summarising the available clinical data on incidence, context, diagnostic features, reported management strategies, and clinical outcomes.

Primary central nervous system lymphoma in the United States, 1975–2017

Background:

Primary central nervous system lymphoma (PCNSL) has received more attention because of an inferior prognosis. Less is known about the incidence rate, histological type, and survival rate of PCNSL, especially in the 2010s.

Methods:

Data of PCNSL from the Surveillance, Epidemiology, and End Results (SEER) registry database (SEER 9 registries and SEER 18 registries) were used. Incidence was estimated by age, gender, race, site, and histological type. Trends were analyzed using joinpoint regression and described as annual percent change (APC) and average annual percent change (AAPC). Five-year overall survival estimates were compared using log-rank tests.

Results:

Most PCNSL occurred in the brain, followed by the spinal cord. The most frequent histological type of PCNSL was diffuse large B-cell lymphoma, followed by marginal zone lymphoma. Incidence rate increased from 0.1/100,000 to 0.5/100,000 with an AAPC of 5.3% from 1975 to 2017. Incidence rates varied greatly between the younger and older age population. The 5-year overall survival rates in SEER 9 registries and SEER 18 registries were 30.5% and 37.4%, respectively. Even though the 5-year overall survival rate significantly increased from 27.9% for the 1975–1979 time period to 44.8% for the 2010–2017 time period, survival benefit could not be expected for patients ⩾60 years. The 5-year survival rate for elderly patients was about 30% in the 2010s.

Conclusion:

With aging, the incidence of PCNSL in the elderly is increased. Over the past decade, no advances have been made in the treatment of elderly PCNSL. Prospective trials with PCNSL are warranted to improve the survival of elderly patients.

Central nervous system ALK-negative anaplastic large cell lymphoma with IRF4/DUSP22 rearrangement

Anaplastic large cell lymphomas (ALCL) are mature T-cell neoplasms, approximately half of which harbor rearrangements of the ALK gene that confer a good prognosis. Recent studies have demonstrated that a significant proportion of ALK-negative ALCLs demonstrate rearrangements of the IRF4/DUSP22 locus that also are typically associated with a favorable prognosis. ALCL with primary involvement of the central nervous system (CNS) is extremely rare. We report what may be the first case of ALK-negative ALCL with IRF4/DUSP22 rearrangement involving the brain in a 55-year-old man. Magnetic resonance imaging demonstrated signal abnormalities in the periventricular region, corpus callosum and cingulate gyrus. Biopsy revealed a diffuse parenchymal and angiocentric infiltrate of CD30-positive cells that showed IRF4/DUSP22 rearrangement by fluorescence in situ hybridization. We also review the clinical and pathologic features of primary CNS ALK-negative ALCLs in the literature and highlight the need for awareness of this entity to optimize appropriate management.

Filtration-Histogram Based Magnetic Resonance Texture Analysis (MRTA) for the Distinction of Primary Central Nervous System Lymphoma and Glioblastoma

Primary central nervous system lymphoma (PCNSL) has variable imaging appearances, which overlap with those of glioblastoma (GBM), thereby necessitating invasive tissue diagnosis. We aimed to investigate whether a rapid filtration histogram analysis of clinical MRI data supports the distinction of PCNSL from GBM. Ninety tumours (PCNSL n = 48, GBM n = 42) were analysed using pre-treatment MRI sequences (T₁-weighted contrast-enhanced (T₁CE), T₂-weighted (T₂), and apparent diffusion coefficient maps (ADC)). The segmentations were completed with proprietary texture analysis software (TexRAD version 3.3). Filtered (five filter sizes SSF = 2-6 mm) and unfiltered (SSF = 0) histogram parameters were compared using Mann-Whitney U non-parametric testing, with receiver operating characteristic (ROC) derived area under the curve (AUC) analysis for significant results. Across all (n = 90) tumours, the optimal algorithm performance was achieved using an unfiltered ADC mean and the mean of positive pixels (MPP), with a sensitivity of 83.8%, specificity of 8.9%, and AUC of 0.88. For subgroup analysis with >1/3 necrosis masses, ADC permitted the identification of PCNSL with a sensitivity of 96.9% and specificity of 100%. For T₁CE-derived regions, the distinction was less accurate, with a sensitivity of 71.4%, specificity of 77.1%, and AUC of 0.779. A role may exist for cross-sectional texture analysis without complex machine learning models to differentiate PCNSL from GBM. ADC appears the most suitable sequence, especially for necrotic lesion distinction.

Primary CNS Extranodal Marginal Zone B-Cell Lymphoma: A Case Series of 2 Patients Treated with External Beam Radiation Therapy

Primary CNS extranodal marginal zone B-cell lymphoma (MZBL) is a rare low-grade non-Hodgkin lymphoma characterized predominantly by small B cells, plasma cells, monocytoid cells, and scattered large immunoblasts. As a slow-growing tumor that remains localized, primary CNS MZBL carries an excellent clinical prognosis. Here, we report two cases of primary CNS MZBL successfully treated using external beam radiation therapy along with a literature review.

Primary diffuse large B-cell lymphoma of the CNS, with a "Lymphomatosis cerebri" pattern

We describe an unusual case of lymphomatosis cerebri in a middle-aged lady presenting with rapid-onset dementia. The lymphomatous infiltrate, instead of forming mass lesions, percolated throughout the brain parenchyma, which is often missed on a stereotactic biopsy and hence warrants caution and awareness about this entity. The nonspecific symptoms at presentation and a variable picture at imaging make this entity diagnostically challenging.

Primary and secondary central nervous system mature T- and NK-cell lymphomas

Primary central nervous system (CNS) mature T- and NK-cell lymphomas are rare, only comprising 2% to 3% of all primary CNS lymphomas. Among them, peripheral T-cell lymphoma, not otherwise specified, anaplastic large cell lymphoma (ALCL), and extranodal NK/T-cell lymphoma (ENKTL) are the commonly reported histological subtypes. Secondary CNS T-cell lymphoma generally affects about 5% of patients with T- or NK-cell lymphoma, with some exceptions. Acute and lymphomatous subtypes of adult T-cell leukemia/lymphoma (ATLL) have high risk of CNS progression, may affect up to 20% of patients; ALK-positive ALCL with extranodal involvement >1 also has high risk of CNS progression. However, the impact and the optimal methodology of CNS prophylaxis remain unclear in systemic T-cell lymphomas. There are little data on the treatment strategy of primary and secondary CNS T-cell lymphoma. Treatment strategy derived from B-cell CNS primary lymphoma is generally used; this includes induction therapy with high-dose methotrexate-based regimens, followed by high-dose chemotherapy with autologous stem cell transplant in fit patients. There are unmet needs for patients who are not fit for intensive chemotherapy. The prognosis after CNS progression in T-cell lymphoma is dismal with the median overall survival of less than 1 year. New agents targeting T-cell lymphomas are emerging and should be tested in patients with mature T- and NK-cell lymphoma who suffer from CNS involvement.

Primary Central Nervous System Lymphoma: Evolving Biologic Insights and Recent Therapeutic Advances

Primary central nervous system lymphoma (PCNSL) is a rare and clinically aggressive disease entity associated with poor survival. Though high-dose methotrexate-based immunochemotherapy approaches are effective at inducing responses, few patients experience long-term durable remissions. Recently, novel insights into the biology of this unique disease have been elucidated and have paved the way for the investigation of rational approaches such as Bruton tyrosine kinase inhibition and immunomodulation. Although these strategies can induce high response rates in PCNSL, remissions are short lived, with median progression-free survivals in the range of 6 months or less. Moving forward, understanding the mechanisms of treatment resistance with these and other novel agents is key to developing optimal combinatorial strategies. New approaches such as immune checkpoint inhibition and chimeric antigen receptor T-cell therapy are under investigation for PCNSL and thus far demonstrate activity in anecdotal clinical experiences. Future trials should focus on investigating novel rational combinations designed to optimally target the biology of PCNSL and simultaneously investigate mechanisms of resistance leading to treatment failure.

Central Nervous System Lymphomas

PURPOSE OF REVIEW

Primary central nervous system (CNS) lymphoma is a rare, aggressive extranodal non-Hodgkin lymphoma confined to the brain, eyes, CSF, or spinal cord without systemic, non-CNS involvement. This article reviews the clinical presentation, imaging characteristics, diagnostic workup, novel pathophysiologic insights, and treatment of immunocompetent patients with primary CNS lymphoma.

RECENT FINDINGS

The prognosis of primary CNS lymphoma has significantly improved over the past few decades because of the introduction of and widespread use of high-dose methotrexate, which is now the backbone of all first-line combination chemotherapy treatments. Despite this progress, durable remission is still observed in only approximately 50% of patients. Novel insights into the pathophysiology of primary CNS lymphoma have identified the B-cell receptor pathway as well as the suppressed tumor immune microenvironment and immune evasion as key mechanisms in the pathogenesis of primary CNS lymphoma. Novel, small molecules and agents targeting these aberrant pathways have been introduced into clinical trials of recurrent/refractory primary CNS lymphomas. Agents such as the Bruton tyrosine kinase (BTK) inhibitor ibrutinib or immunomodulatory drugs such as lenalidomide and pomalidomide have shown promising response rates in the relapsed setting.

SUMMARY

Diagnosis of primary CNS lymphoma requires a high level of suspicion because clinical signs and deficits can vary and depend on the involved CNS compartments. Rapid initiation of therapy is essential for recovery and prognosis. The optimal treatment regimen has not been defined, but methotrexate-based chemotherapy regimens are considered the standard treatment approach for induction treatment. Novel, targeted agents have recently been introduced into the therapeutic arsenal.

Risk Factors for Early Mortality in Patients with Primary Central Nervous System Lymphoma: A Large-Cohort Retrospective Study

OBJECTIVE

The present study assessed early mortality (within 1 and 3 months) in patients with primary central nervous system lymphoma (PCNSL) and identified the risk factors associated with early mortality.

METHODS

We extracted the data for patients with PCNSL from the Surveillance, Epidemiology, and End Results dataset using the SEER∗Stat, version 8.3.5, software.

RESULTS

A total of 8091 patients with PCNSL were enrolled in the present study. Of the 8091 patients, 57.94% were men and 42.06% were women. The mean age was 59.50 ± 16.11 years. The rate of death within 1 and 3 months was 10.67% and 29.16%, respectively. During the past 20 years, early mortality declined significantly. The common causes of early death were non-Hodgkin lymphoma and other infectious and parasitic diseases, including human immunodeficiency virus. Our results showed that gender, age at diagnosis, ethnicity, histological subtype, marital status, tumor location, surgery, radiotherapy, and chemotherapy were associated with early mortality within 1 or 3 months.

CONCLUSION

The rate of early mortality has declined significantly during the past 20 years. The risk factors for early mortality within 1 or 3 months after a PCNSL diagnosis included advanced age, male gender, black race, frontal lobe location, unmarried, diffuse large B-cell lymphoma, no surgery, no chemotherapy, and no radiotherapy.

An international multicenter retrospective analysis of patients with extranodal marginal zone lymphoma and histologically confirmed central nervous system and dural involvement

Marginal zone lymphoma of the central nervous system (CNS MZL) is rare. The clinical features, treatment, and prognosis are not well characterized. We performed a multicenter retrospective study of CNS MZL. Twenty-six patients were identified: half with primary and half with secondary CNS involvement. The median age was 59 years (range 26-78), 62% female and 79% with ECOG performance status ≤ 1. The most common disease site was the dura (50%). Treatment was determined by the treating physician and varied substantially. After a median follow up of 1.9 years, the estimated 2-year progression-free (PFS) and overall survival (OS) rates were 59% and 80%, respectively. Secondary CNS MZL was associated with 2-year OS of 58%. CNS MZL is rare, but relative to other forms of CNS lymphoma, outcomes appear favorable, particularly among the subset of patients with dural presentation and primary CNS presentation.