Pathology with clinical correlations of primary central nervous system non-Hodgkin's lymphoma. The Massachusetts General Hospital experience 1958-1989

Predictors for the Differentiation between Glioblastoma, Primary Central Nervous System Lymphoma, and Metastasis in Patients with a Solitary Enhancing Intracranial Mass

Introduction  Differentiation between glioblastoma (GBM), primary central nervous system lymphoma (PCNSL), and metastasis is important in decision-making before surgery. However, these malignant brain tumors have overlapping features. This study aimed to identify predictors differentiating between GBM, PCNSL, and metastasis. Materials and Methods  Patients with a solitary intracranial enhancing tumor and a histopathological diagnosis of GBM, PCNSL, or metastasis were investigated. All patients with intracranial lymphoma had PCNSL without extracranial involvement. Demographic, clinical, and radiographic data were analyzed to determine their associations with the tumor types. Results  The predictors associated with GBM were functional impairment ( p  = 0.001), large tumor size ( p  < 0.001), irregular tumor margin ( p  < 0.001), heterogeneous contrast enhancement ( p  < 0.001), central necrosis ( p  < 0.001), intratumoral hemorrhage ( p  = 0.018), abnormal flow void ( p  < 0.001), and hypodensity component on noncontrast cranial computed tomography (CT) scan ( p  < 0.001). The predictors associated with PCNSL comprised functional impairment ( p  = 0.005), deep-seated tumor location ( p  = 0.006), homogeneous contrast enhancement ( p  < 0.001), absence of cystic appearance ( p  = 0.008), presence of hypointensity component on precontrast cranial T1-weighted magnetic resonance imaging (MRI; p  = 0.027), and presence of isodensity component on noncontrast cranial CT ( p  < 0.008). Finally, the predictors for metastasis were an infratentorial ( p  < 0.001) or extra-axial tumor location ( p  = 0.035), smooth tumor margin ( p  < 0.001), and presence of isointensity component on cranial fluid-attenuated inversion recovery MRI ( p  = 0.047). Conclusion  These predictors may be used to differentiate between GBM, PCNSL, and metastasis, and they are useful in clinical management.

Role of Positron Emission Tomography in Primary Central Nervous System Lymphoma

Simple Summary

Primary central nervous system lymphoma (PCNSL) is a rare but highly aggressive lymphoma with increasing incidence in immunocompetent patients. To date, the only established biomarkers for survival are age and functional status. Currently, the magnetic resonance imaging (MRI) criteria of the International Collaborative Group on Primary Central Nervous System Lymphoma are the only ones recommended for follow-up. However, early occurrence of recurrence after treatment in patients with a complete response on MRI raises the question of its performance in assessing residual disease. While the use of ¹⁸F-fluorodeoxyglucose body positron emission tomography for identification of systemic disease has been established and can be pivotal in patient treatment decisions, the role of brain PET scan is less clear. Here we review the potential role of PET in the management of patients with PCNSL, both at diagnosis and for follow-up under treatment.

Abstract

The incidence of primary central nervous system lymphoma has increased over the past two decades in immunocompetent patients and the prognosis remains poor. A diagnosis and complete evaluation of the patient is needed without delay, but histologic evaluation is not always available and PCNSL can mimic a variety of brain lesions on MRI. In this article, we review the potential role of ¹⁸F-FDG PET for the diagnosis of PCNSL in immunocompetent and immunocompromised patients. Its contribution to systemic assessment at the time of diagnosis has been well established by expert societies over the past decade. In addition, ¹⁸F-FDG provides valuable information for differential diagnosis and outcome prediction. The literature also shows the potential role of ¹⁸F-FDG as a therapeutic evaluation tool during the treatment and the end of the treatment. Finally, we present several new radiotracers that may have a potential role in the management of PCNSL in the future.

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.

Primary Central Nervous System Lymphoma: A Case of Solitary Brain Lesion

Primary central nervous system lymphoma (PCNSL) is an uncommon variant of extranodal non-Hodgkin’s lymphoma (NHL) that involves the brain, leptomeninges, eyes, or spinal cord without evidence of systemic disease.

This article presents a case of a 63-year-old Caucasian female with high-grade B-cell lymphoma who was found to have a solitary brain lesion and no distant metastasis upon diagnosis. The patient had left-sided weakness and difficulty standing on presentation and was found to have a right frontal lobe mass with surrounding mild vasogenic edema and a small focal area of hemorrhage concerning for high-grade glioma versus lymphoma on MRI. However, pathology results revealed high-grade B-cell lymphoma.

The case reinforces the importance of working up any lesion suspicious for lymphoma/glioma. Diagnosis of high-grade B-cell lymphoma can be difficult based on morphological and cytological appearance due to varying gene expression and presentation at diagnosis. It can closely mimic diffuse B-cell lymphoma. Extensive workup including HIV serology, MRI imaging, evaluation for spinal cord involvement, and lumbar puncture (LP), to rule out cerebrospinal fluid (CSF) involvement, prior to initiating treatment needs to be done. The case also addresses high-grade methotrexate (MTX)-based chemotherapy as a treatment that improves mortality in patients with primary central nervous system (CNS) lymphoma.

Positron emission tomography and magnetic resonance imaging in primary central nervous system lymphoma-a narrative review

This review addresses the challenges of primary central nervous system (CNS) lymphoma diagnosis, assessment of treatment response, and detection of recurrence. Primary CNS lymphoma is a rare form of extra-nodal non-Hodgkin lymphoma that can involve brain, spinal cord, leptomeninges, and eyes. Primary CNS lymphoma lesions are most commonly confined to the white matter or deep cerebral structures such as basal ganglia and deep periventricular regions. Contrast-enhanced magnetic resonance imaging (MRI) is the standard diagnostic modality employed by neuro-oncologists. MRI often shows common morphological features such as a single or multiple uniformly well-enhancing lesions without necrosis but with moderate surrounding edema. Other brain tumors or inflammatory processes can show similar radiological patterns, making differential diagnosis difficult. [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) has selected utility in cerebral lymphoma, especially in diagnosis. Primary CNS lymphoma can sometimes present with atypical findings on MRI and FDG PET, such as disseminated disease, non-enhancing or ring-like enhancing lesions. The complementary strengths of PET and MRI have led to the development of combined PET-MR systems, which in some cases may improve lesion characterization and detection. By highlighting active developments in this field, including advanced MRI sequences, novel radiotracers, and potential imaging biomarkers, we aim to spur interest in sophisticated imaging approaches.

Primary central nervous system lymphoma in immunocompetent patients: A regional cancer center experience

Background:

Primary central nervous system lymphoma (PCNSL) is a rare form of aggressive extranodal non-Hodgkin's lymphoma which occurs in both immunocompromised and immunocompetent patients. It has an overall poor prognosis in spite of a multimodality treatment approach including chemotherapy and radiotherapy. This study attempts to further delineate the clinicopathological, immunohistochemical, and radiological profile of PCNSL at Kidwai Memorial Institute of Oncology, Karnataka, India.

Materials and Methods:

All the pathologically confirmed PCNSL cases between January 2010 and June 2016, at our center, were analyzed retrospectively. The influence of potential prognostic parameters on overall survival (OS) was investigated by log-rank test and Cox regression analysis.

Results:

Of the 26 PCNSL patients, 17 (65.3%) were males. Median age at diagnosis was 42.5 years. None of the patients had HIV or Epstein-Barr virus positivity and only four patients (15.4%) had B-symptoms. The most common location in the brain was cerebral hemispheres in 15 patients (57%) and 10 patients (38.5%) had multiple intracranial lesions. Histologically, all were diffuse large B-cell lymphomas, except one case of anaplastic large cell lymphoma. Immunohistochemically, 18 patients (69%) had MUM 1 positivity and 20 cases (77%) belonged to nongerminal center subtype. DeAngelis protocol was followed in 24 patients (92%), and among this cohort, Memorial Sloan Kettering Cancer Center Class 1 (n = 17) and Class 2 (n = 7) patients had a median OS of 25 months and 11 months, respectively.

Conclusion:

None of the potential prognostic factors had a statistically significant influence on OS in our patients. High-dose methotrexate combined with radiation is an effective therapeutic approach. However, further prospective studies with a large number of patients are needed to identify more effective primary chemotherapy regimens to further improve the treatment outcome.

Outcomes of Autologous Stem Cell Transplant Consolidation in Primary Central Nervous System Lymphoma: A Mayo Clinic Experience

A paucity of randomized phase III clinical trials in primary central nervous system lymphoma (PCNSL) has resulted in no uniform consensus on the optimal strategy for consolidation and conditioning regimens for autologous stem cell transplant (ASCT). The past 2 decades have witnessed a preference for thiotepa (TT)-based conditioning regimens due to superior central nervous system penetration. We retrospectively evaluated outcomes of patients with PCNSL who underwent ASCT at Mayo Clinic, Rochester over the past 2 decades, and the impact of TT-based conditioning regimens. Fifty-six patients underwent transplant for PCNSL, with 25 and 31 patients receiving BEAM (non-thiotepa) and carmustine (BCNU)/TT-based conditioning, respectively. All patients received high-dose methotrexate-based induction therapy. While the BCNU/TT group had higher risk disease features such as high International Extranodal Lymphoma Study Group prognostic score, elevated cerebrospinal fluid protein, and older patient population, there was no significant difference at 2 years post-transplant in progression-free survival (BEAM 68.0% [46.1% to 82.5%] versus BCNU/TT, 65.5% [45.2% to 79.8%], P = .99) or overall survival (OS) (84.0% [62.8% to 93.7%] in the BEAM group versus 81.6% [61.3% to 91.9%] in the BCNU/TT group, P = .95). Disease response status before transplant significantly affected the outcomes as those in complete remission had an OS at 2 years post-transplant of 94.7% (68.1% to 99.2%) in the BEAM group and 90.5% (67.0% to 97.5%) in the BCNU/TT group compared with those in partial response, 57.1% (17.2% to 83.7%) in BCNU/TT group and 50.0% (11.1% to 80.4%) in the BEAM group, respectively (P < .0001). Our retrospective cohort adds to the currently available literature and identifies the disease status before transplant as a significant factor affecting survival.

Lymphomatosis cerebri with cauda equina lymphoma

PURPOSE/AIM

Lymphomatosis cerebri (LC) and cauda equina lymphoma are both rare forms of primary central nervous system lymphoma (PCNSL). LC is characterized by diffuse bilateral non-enhancing (or partially enhancing) inltrative lesions without mass effect, which can be easily confused with other forms of leukoencephalopathy and, thus, lead to delays in diagnosis.

CASE REPORT

For the first time, a case of LC concomitant with cauda equina involvement confirmed by brain stereotactic biopsy is presented.

CONCLUSIONS

This case highlights the necessity of using a multimodal strategy in diagnosing PCNSL, including multimodal magnetic resonance, cerebral spinal fluid cytology, flow cytometry and fluorodeoxyglucose positron emission tomography/computed tomography.

Primary Diffuse Large B-Cell Non-Hodgkin's Lymphoma of the Thoracic Spine Presented Initially as an Epigastric Pain

Non-Hodgkin's lymphoma (NHL) compromises the vast majority of lymphomas and predominantly takes on the form of B-cell lymphomas. More specifically, 30% of all newly diagnosed cases of NHL in the United States (US) are of diffuse large B-cell lymphoma (DLBCL) type, making it the most prevalent form of NHL in the US. Arising from either nodal or extra-nodal lymphatic tissue origin, DLBCL is an aggressive tumor which is fatal if left untreated. Primary central nervous system lymphoma is rare; however, when diagnosed, it presents as a DLBCL in 90% of patients. Herein, we present an elderly male complaining initially of acute epigastric pain but soon afterward developed acute spinal cord compressive symptoms; subsequently, it was found to be caused by a primary DLBCL diagnosed in the thoracic spinal cord. This case report presents a rare condition with unexpected initial presentation, and we attempt to illustrate the importance of early detection and treatment of DLBCL in attaining more favorable prognostic and survival rates among patients. Written consent was obtained from the patient after reading a written summary of the case report. This consent was checked and approved from the Scientific Board of the University of Aleppo.

MYD88 L265P mutation and CDKN2A loss are early mutational events in primary central nervous system diffuse large B-cell lymphomas

The genetic alterations that define primary central nervous system lymphoma (PCNSL) are incompletely elucidated, and the genomic evolution from diagnosis to relapse is poorly understood. We performed whole-exome sequencing (WES) on 36 PCNSL patients and targeted MYD88 sequencing on a validation cohort of 27 PCNSL patients. We also performed WES and phylogenetic analysis of 3 matched newly diagnosed and relapsed tumor specimens and 1 synchronous intracranial and extracranial relapse. Immunohistochemistry (IHC) for programmed death-1 ligand (PD-L1) was performed on 43 patient specimens. Combined WES and targeted sequencing identified MYD88 mutation in 67% (42 of 63) of patients, CDKN2A biallelic loss in 44% (16 of 36), and CD79b mutation in 61% (22 of 36). Copy-number analysis demonstrated frequent regions of copy loss (ie, CDKN2A), with few areas of amplification. CD79b mutations were associated with improved progression-free and overall survival. We did not identify amplification at the PD-1/PD-L1 loci. IHC for PD-L1 revealed membranous expression in 30% (13 of 43) of specimens. Phylogenetic analysis of paired primary and relapsed specimens identified MYD88 mutation and CDKN2A loss as early clonal events. PCNSL is characterized by frequent mutations within the B-cell receptor and NF-κB pathways. The lack of PD-L1 amplifications, along with membranous PD-L1 expression in 30% of our cohort, suggests that PD-1/PD-L1 inhibitors may be useful in a subset of PCNSL. WES of PCNSL provides insight into the genomic landscape and evolution of this rare lymphoma subtype and potentially informs more rational treatment decisions.

Curative effect of methotrexate combined with teniposide in the treatment of primary central nervous system lymphoma

The present study aimed to investigate the curative effect of high-dose methotrexate (HD-MTX) combined with teniposide (Vm26) vs. HD-MTX alone in the treatment of primary central nervous system lymphoma (PCNSL), in order to provide data for assisting decisions associated with clinical treatment. Data from 56 patients with PCNSL admitted in Shanghai Huashan Hospital (Shanghai, China) from January 2009 to December 2014 were included into the present study. Clinical data, curative effects and prognosis of patients in these two groups were retrospectively analyzed using SPSS 20 statistical software. In the HD-MTX+Vm26 group, 12 patients (42.85%) achieved complete remission (CR) and 10 patients (35.71%) achieved partial remission (PR), while in the HD-MTX group 7 patients (25%) achieved CR and 11 patients (39.29%) achieved PR (P=0.158). The median progression-free survival (PFS) time was 22 months in the HD-MTX+Vm26 group and 12 months in the HD-MTX group (P=0.019). The median overall survival time was 57 months in the HD-MTX+Vm26 group, and 28 months in the HD-MTX group (P=0.013). Compared with HD-MTX alone, the combined treatment of HD-MTX+Vm26 had an improved curative effect in the treatment of PCNSL, effectively controlled tumor progression in patients, prolonged survival time and improved prognosis. Age was an independent prognostic factor in patients with PCNSL. Patients with an age of ≤60 years exhibited longer PFS compared with patients with an age of >60 years.

Recurrence of nasal type NK/T cell lymphoma presenting as neurolymphomatosis on 18F-FDG PET/CT: A case report and literature review

INTRODUCTION

NK/T cell lymphomas seldom involve the peripheral nervous system. We report a case of recurrent nasal type NK/T cell lymphoma presenting as neurolymphomatosis and its manifestation on F-FDG PET/CT.

PATIENT CONCERNS

A 55-year old man presented with a mass in the right nasal cavity was diagnosed with extranodal NK/T cell lymphoma, nasal type. F-FDG PET/CT showed intense FDG uptake within the mass. After radiotherapy the nasal tumor was completely relieved, but the patient experienced numbness and amyosthenia in the right upper extremity one week after completion of radiotherapy.

DIAGNOSIS

PET/CT showed intense FDG uptake in the brachial plexus, axillary, suprascapular and median nerves, suggestive of recurrence of lymphoma presenting as neurolymphomatosis.

INTERVENTIONS

After 1 cycle of chemotherapy, the follow-up PET/CT showed markedly reduced FDG uptake in the previous involved nerves, demonstrating a very good response of neurolymphomatosis to chemotherapy.

OUTCOMES

The patient finally had a progression free survival of 8 months after completion of 4 cycles of chemotherapy and autologous stem cell transplantation.

LESSONS

As neurolymphomatosis is a rare neurologic manifestation in recurrence of NK/T cell lymphoma, recognition of its presentation is important for prompt diagnosis and initiating treatment approach.

Diffusion kurtosis imaging differs between primary central nervous system lymphoma and high-grade glioma and is correlated with the diverse nuclear-to-cytoplasmic ratio: a histopathologic, biopsy-based study

OBJECTIVES

To determine whether water kurtosis and diffusional metrics derived from diffusional kurtosis imaging (DKI) within primary central nervous system lymphomas (PCNSLs) and high-grade gliomas (HGGs) correlate with cellularity and/or nuclear-to-cytoplasmic (N/C) ratio.

METHODS

Forty-four and 43 pathologically confirmed high-grade glioma and primary central nervous system lymphoma specimens between May 2013 and November 2016 were retrospectively reviewed. Diffusional metrics, kurtosis metrics, cellularity, and N/C ratios in PCNSLs and HGGs were compared using the Mann-Whitney U test (significant level, p < 0.007 [0.05/7]); Bonferroni correction).

RESULTS

Mean kurtosis (MK), axial kurtosis (K_//), and radial kurtosis (K_⊥) in PCNSLs were 0.857 (0.693-0.924), 0.837 (0.660-0.941), and 0.834 (0.685-0.937), respectively; and 0.629 (0.524-0.716), 0.575 (0.511-0.689), and 0.675 (0.532-0.766), respectively, in HGGs (all p < 0.001). No significant differences in fractional anisotropy (FA), mean diffusion (MD), axial diffusion (λ_//), and radial diffusion (λ_⊥) were found between HGGs and PCNSLs. Cellularity was higher in PCNSLs than in HGGs (p = 0.125); whereas, the N/C ratio in PCNSLs was significantly higher than that in HGGs (p < 0.001). All DKI metrics (FA, MD, λ_//, λ_⊥, MK, K_//, and K_⊥) were significantly correlated with N/C ratio in PCNSLs with correlation coefficients being rho = 0.418, - 0.722, - 0.525, - 0.768, 0.704, 0.579, and 0.686, respectively. Cellularity in PCNSLs and HGGs did not correlate with any kurtosis or diffusional metrics.

CONCLUSIONS

Difference of kurtosis parameters between PCNSLs and HGGs is correlated with their diverse N/C ratio.

KEY POINTS

• DKI has considerable value in differentiating between PCNSLs and HGGs. • DKI can provide important information on nuclear-to-cytoplasmic ratio. • Difference of kurtosis parameters between PCNSLs and HGGs correlated well with their diverse N/C ratios.

High Detection Rate of MYD88 Mutations in Cerebrospinal Fluid From Patients With CNS Lymphomas

PURPOSE

Biopsy is the gold standard for the diagnosis of primary CNS lymphoma (PCNSL). However, surgical biopsy has problems of morbidity related to hemorrhagic complications and false-negative findings, so safer and more reliable diagnostic methods are required. The aim of this study is to detect the MYD88 mutation, an important driver mutation, in the cerebrospinal fluid (CSF) of patients with CNS lymphoma.

PATIENTS AND METHODS

Twenty-six patients with CNS lymphoma (20 primary CNS lymphoma and six CNS relapse from systemic lymphoma) were studied. We extracted cell-free DNA (cfDNA) from CSF by lumbar puncture. cfDNA was extracted from 1 mL of CSF, and Sanger sequencing and droplet digital polymerase chain reaction (ddPCR) were performed. Furthermore, we performed DNA sequencing of MYD88 in 21 cases with available surgically obtained formalin-fixed paraffin-embedded (FFPE) tissue and compared the results.

RESULTS

The median cfDNA amount extracted from 1 mL CSF was 219 ng/mL (25th to 75th percentile, 129 to 333 ng/mL). MYD88 mutations were detected from CSF in 76.9% (20 of 26 cases), and L265P in exon 5 was the most frequent mutation in 19 out of 20 (95.0%) cases. S219C in exon 3 was detected in one case. In four patients, MYD88 mutation was confirmed by ddPCR but not by Sanger sequencing. In all 21 cases with sufficient FFPE tissue for DNA analysis, the detection of MYD88 mutation from cfDNA was consistent with those of tumor-derived DNA from FFPE tissue.

CONCLUSION

This pilot study provided evidence that the somatic driver mutation MYD88 can be reliably detected by combination of Sanger sequencing and ddPCR in the cfDNA taken from 1 mL of CSF in patients with CNS lymphomas.

Clinicopathologic correlates of MYD88 L265P mutation and programmed cell death (PD-1) pathway in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) patients have a poorer prognosis than systemic lymphoma. Gain-of-function MYD88 c.794T > C (p. L265P) mutation and programed cell death-1 (PD-1) pathway alterations are potential targetable pathways. Our study objective was to determine the clinicopathologic correlates of MYD88 mutation and PD-1 alterations in PCNSL and the impact of Epstein-Barr virus (EBV) infection. We studied 53 cases including 13 EBV-associated (EBV^pos) PCNSL, 49% harbored MYD88 mutation, none seen in EBV^pos PCNSL. MYD88 protein expression did not correlate with MYD88 mutation. T-cell and macrophage infiltration was common. All PD-L1-positive tumors were EBV^pos. Two PD-L1 positive tumors showed 9p24.1/PD-L1 locus alterations by Fluorescence In Situ Hybridization. T cells and macrophages expressed PD-1 and/or PD-L1 in 98% and 83% cases, respectively. MYD88 mutation or protein expression and PD-1 or PD-L1 expression did not predict outcome. We hypothesize that EBV^pos PCNSL has a distinct activation mechanism, independent of genetic alterations.

Primary CNS Lymphoma Arising from the 4th Ventricle: A Case Report and Review of the Literature

A 65-year-old male with a history of ischemic strokes, seizures, and subarachnoid hemorrhage presented with a 4-week history of progressive diplopia, vertigo, nausea, and vomiting. Magnetic resonance imaging (MRI) revealed a 2.5 × 1.8 × 1.7 cm posterior fossa mass arising from the roof of the 4^th ventricle extending into the cerebellar vermis. Posterior fossa craniotomy with stereotactic biopsy confirmed a locally invasive diffuse large B-cell lymphoma (DLBCL). Primary central nervous system lymphoma (PCNSL) arising from the 4^th ventricle is a rare extranodal manifestation of non-Hodgkin lymphoma (NHL), with few cases documented in the literature. Review of available cases lends support that lymphoma arising from the 4^th ventricle has a variable clinical presentation, occurs most commonly in immunocompetent males, and should be on the differential of any immunocompetent adult presenting with a posterior fossa mass. Optimal treatment modalities are based largely on phase 2 clinical trials, and recommended guidelines regardless of anatomic location should be adhered to.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma: Comparison of clinical features and risk factors suggestive of underlying lymphomas

BACKGROUND

We studied patients with chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma and measured risk factors suggestive of an underlying lymphoma and follow-up outcomes.

METHODS

CLIPPERS patients associated with or without lymphoma were included into this study. Clinical presentations were documented, risk factors suggestive of an underlying lymphoma were tested, and prognostic differences in terms of death were compared.

RESULTS

Ten patients had a diagnosis of CLIPPERS associated with lymphoma, with 6 B-cell non-Hodgkin lymphoma, 2 T-cell non-Hodgkin lymphoma and 2 Hodgkin lymphoma. Using multivariate logistic analysis, the following 3 independent risk factors were found to be related to a final diagnosis of lymphoma: hyperreflexia (HR 16.56; 95% CI 1.03-265.29; p = 0.032), elevated protein in CSF (HR 11.59; 95% CI 1.24-108.39; p = 0.047), and recurrences between 2 months and 1 year after treatment (HR 29.27; 95% CI 2.09-409.58; p = 0.012). The model calibration was satisfactory (p = 0.392 with the Hosmer-Lemeshow test), and the discrimination power was good (area under the receiver operating characteristic curve 0.921; p < 0.001, 95% CI 0.826-1.000). Patients with CLIPPERS associated with lymphoma had higher mortality rate and lymphoma was a significant predictor of total mortality (HR 0.040; 95% CI 0.006-0.262; p = 0.001).

CONCLUSIONS

Hyperreflexia, elevated protein in CSF and recurrences between 2 months and 1 year after treatment are risk factors suggesting an underlying lymphoma. Relapses during high-dose steroids maintenance therapy can be indicative of lymphoma, too. Patients having CLIPPERS associated with lymphoma have a worse prognosis than those without lymphoma.

Intracranial Cell Lymphomas That Mimic Meningiomas: Case Report To Understand Complex Genetic, Radiologic, and Histopathologic Entities

BACKGROUND

We describe a patient affected by a T-cell primary central nervous system lymphoma (PCNSL) with highly aberrant specific B-cell markers (CD79a and CD20). An unusual imaging presentation leads us to misdiagnose this lesion for a meningioma and perform surgical resection.

CASE DESCRIPTION

We think that this infrequent anatomic presentation might be due to the aberrant specific B-cell markers (CD79a and CD20) genotype expression. We believe this case to be relevant in order to appreciate the diagnosis of cerebral lymphomas according to various presentations. We wonder whether it was not the aberrant genotype that contributed to this quirky presentation and ultimately if surgery in PCNSL should not be discussed?

CONCLUSIONS

Furthermore, this case calls attention to the complexity of lineage assignment, imaging diagnosis, and treatment strategy in PCNSL.

Autologous Stem-Cell Transplantation for Primary Central Nervous System Lymphoma: Systematic Review and Meta-analysis

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is an aggressive form of non-Hodgkin lymphoma. Methotrexate is first-line chemotherapy. Autologous stem-cell transplantation (ASCT) is increasingly used as an alternative consolidative treatment to whole-brain radiotherapy.

METHODS

A systematic search of several databases was conducted up through January 10, 2018. Two investigators independently assessed study eligibility and extracted the data. Studies that reported survival outcomes after ASCT were included.

RESULTS

We screened 1517 references and included 43 studies. ASCT was used as consolidative treatment or as salvage treatment/at relapse. Thiotepa, busulfan, and cyclophosphamide and carmustine/thiotepa were commonly used conditioning regimens. In the consolidation setting, 94% of patients experienced or maintained complete or partial response after ASCT. The rates of overall survival (OS) and progression-free survival (PFS) were 94%, 86%, 82%, and 70% and 79%, 70%, 64%, and 54% after 1, 2, 3, and 5 years, respectively. The overall risk of relapse at 5 years was 24%. In the salvage/relapse settings, 85% of patients experienced or maintained complete response or partial response after ASCT. The rates of OS and PFS were 75%, 63%, 56%, and 54% and 85%, 62%, 59%, and 54% after 1, 2, 3, and 5 years, respectively. The risk of relapse at 5 years was 29%. Subgroup analysis showed that the use of carmustine and thiotepa as a conditioning regimen carried the lowest risk of transplant-related mortality. The thiotepa, busulfan, and cyclophosphamide regimen, on the other hand, showed numerically superior OS and PFS rates.

CONCLUSION

This review provides estimates for response and survival to aid in decision making when considering ASCT for patients with PCNSL.

Cerebellar large B-cell lymphoma: a case report

Background

Primary central nervous system lymphoma is a rare, malignant non-Hodgkin lymphoma that can arise in the brain, spinal cord, eye, leptomeninges, or cranial nerves. Primary central nervous system lymphoma is rare, accounting for 2–6% of all primary brain neoplasms and 1–2% of all non-Hodgkin lymphomas, and it usually presents as a solitary lesion. Cerebellar involvement is present in only 9% of cases. We present an unusual case of primary central nervous system lymphoma presenting as multiple lesions in the cerebellum in an immunocompetent host.

Case presentation

A 71-year-old Caucasian man presented to our hospital with acute onset of dizziness, nausea, vomiting, and gait imbalance. Contrast-enhanced computed tomography revealed three intensely enhancing masses in the right cerebellar hemisphere. Whole-body positron emission tomography and computed tomography failed to demonstrate a primary tumor of origin outside the central nervous system. The patient underwent right suboccipital craniotomy with partial resection of the visible tumor from the right cerebellum. Histopathology revealed diffuse large B-cell lymphoma, non-germinal center type.

Conclusions

Primary central nervous system lymphoma is rare, even more so in the cerebellum. However, the overall incidence of primary central nervous system lymphoma is rising in both immunocompromised and immunocompetent patients. The highly aggressive nature of primary central nervous system lymphoma necessitates timely diagnosis and intervention. In this report, we review the available literature for a better understanding of the pathophysiology and management of primary central nervous system lymphoma. To the best of our knowledge, this is the first reported case of a patient with primary central nervous system lymphoma presenting with multiple masses in the cerebellum.

Prolonged third complete remission after busulfan, thiotepa, and autologous stem cell transplant in a primary central nervous system lymphoma patient

Primary central nervous system lymphoma (PCNSL) remains a therapeutic challenge due to impaired drugs diffusion as a result of the blood-brain barrier and high risk of relapse. Patients with good performance status, chemo-sensitive disease, and eligible for autologous stem cell transplant (ASCT) may benefit from salvage therapy and therapeutic intensification that may allow long-term remission.

Primary CNS Burkitt Lymphoma: A Case Report of a 55-Year-Old Cerebral Palsy Patient

With primary central nervous system lymphoma (PCNSL) being a rare disease, the subtype of Burkitt lymphoma (BL) presenting as a sole CNS lesion is an even more exceptional diagnosis. A case of coexistent primary CNS Burkitt lymphoma (PCNSBL) with cerebral palsy (CP) is presented. A 55-year-old Caucasian male presented with increasing bilateral lower extremity weakness above his baseline in addition to signs of increased intracranial pressure. Four abnormal enhancing masses were detected on MRI with biopsy results consistent with Burkitt lymphoma. Complete staging workup was completed with no evidence of extra-CNS disease noted on PET/CT, bone marrow biopsy, or cerebral spinal fluid analysis. The patient was treated with intravenous as well as intrathecal chemotherapy and found to be in a complete remission at six months. Recurrence in the CNS was observed four months later with treatment consisting of whole brain radiation as well as intrathecal chemotherapy. Thirty months after diagnosis, the patient remains disease-free. To our knowledge, this is the first case of PCNSBL in the setting of CP. A review of literature regarding treatment options in this controversial setting is provided.

Non-invasive detection of somatic mutations using next-generation sequencing in primary central nervous system lymphoma

Purpose

Primary central nervous system lymphomas (PCNSL) have recurrent genomic alterations. The main objective of our study was to demonstrate that targeted sequencing of circulating cell-free DNA (cfDNA) released by PCNSL at the time of diagnosis could identify somatic mutations by next-generation sequencing (NGS).

Patients and Methods

PlasmacfDNA and matched tumor DNA (tDNA) from 25 PCNSL patients were sequenced using an Ion Torrent Personal Genome Machine (Life Technologies^®). First, patient-specific targeted sequencing of identified somatic mutations in tDNA was performed. Then, a second sequencing targeting MYD88 c.T778C was performed and compared to plasma samples from 25 age-matched control patients suffering from other types of cancer.

Results

According to the patient-specific targeted sequencing, eight patients (32% [95% CI 15-54%]) had detectable somatic mutations in cfDNA. Considering MYD88 sequencing, six patients had the specific c.T778C alteration detected in plasma. Using a control group, the sensitivity was 24% [9-45%] and the specificity was 100%. Tumor volume or deep brain structure involvement did not influence the detection of somatic mutations in plasma.

Conclusion

This pilot study provided evidence that somatic mutations can be detected by NGS in the cfDNA of a subset of patients suffering from PCNSL.

Incidence and Radiographic Findings of Primary Central Nervous System Lymphoma in Immunocompetent Patients in Southern Thailand

Aims and Background

In the last two decades there have been conflicting reports concerninga rising incidence of primary central nervous system lymphoma (PCNSL) in immunocompetent patients. This study is being conducted to review the incidence and radiographic findings of PCNSL in a large tertiary care institution in southern Thailand.

Patients

A review was carried out in Songklanagarind University Hospital of the clinical records, CT and MRI images of immunocompetent patients who had histologically proven PCNSL diagnosed between January 1993 and December 2004.

Results

A total of 25 PCNSL patients were diagnosed over a 12-year period. The incidence trend was rising but not to a statistically significant extent. The median age at diagnosis was 57.4 years. Based on the Working Formulation classification, diffuse large cell was the most common subtype. All of the 20 patients with available immunohistochemical results had B-cell lymphomas. The radiographic findings in our series show that the majority of patients had a single lesion (60%) at a supratentorial location (50%). Most of the lesions were well circumscribed. Based on the density of the lesions before administration of a contrast medium, 56% of the lesions on CT images appeared hyperdense. On T1-weighted MRI images, the lesions of our patients were most frequently hypointense (67%) while the T2-weighted images were more commonly hyperintense (60%) and contrast enhancement was found in all lesions. There were 21 patients who received whole brain radiotherapy with doses ranging between 4.2 and 6.0 Gy. The median survival time was 14.4 months.

Conclusions

This study indicates that there has been no significant increase in PCNSL cases over the last 12 years. The recognition of characteristic imaging features of PCNSL may facilitate a stereotactic procedure before steroid administration. In addition, we provide evidence that radiotherapy alone is insufficient in PCNSL.

Primary central nervous system lymphoma: a new prognostic model for patients with diffuse large B-cell histology

Background

Age and performance status are important prognostic factors in primary central nervous system (CNS) lymphoma. Although several prognostic models have been proposed, there is no consensus on the optimal model for patients with diffuse large B-cell histology.

Methods

Seventy-seven patients with primary CNS diffuse large B-cell lymphoma were retrospectively analyzed to determine factors affecting survival. Three Western models were applied to our eligible patients; we devised a novel model based on our findings.

Results

The median patient age was 59 years (range, 29–77); the median event-free and overall survival (OS) durations were 35.9 and 12.6 months, respectively. Nottingham/Barcelona and Memorial Sloan Kettering Cancer Center models were applicable to our cohorts. Multivariate analysis showed that advanced age, multifocal lesions, and high cerebrospinal fluid (CSF) protein concentrations were correlated significantly. A novel model for predicting prognosis was then developed based on these variables. Each variable was assigned 1 point; patients with a total score of 0, 1, 2, and 3 were categorized into the low- (N=17), moderate- (N=26), high- (N=14), and very high-risk groups (N=4), respectively. Sixty-one patients were eligible considering our model; the median OS was 58.2, 34.8, 9.0, and 1.8 months in the low-, moderate-, high-, and very high-risk groups, respectively (P<0.01).

Conclusion

Advanced age, multifocal lesions, and high CSF protein concentration were adversely related with prognosis. Our model can be helpful in pre-treatment risk stratification for patients with primary CNS lymphoma with diffuse large B-cell histology.

18F-FDG PET/CT in primary brain lymphoma

The actual role of 18F-FDG PET/CT in evaluating primary brain lymphoma is still an open issue. Brain lymphoma usually show elevated 18F-FDG uptake, often higher than other brain tumors or inflammatory processes, but the metabolic behavior of this lymphoma is not still understood. Our aim was to investigate the particular metabolic behavior of this lymphoma. Forty six patients (21 female, 25 male) with histologically-confirmed brain lymphoma who underwent 18F-FDG PET/CT from vertex to the mid-thigh for initial staging were retrospectively evaluated. The PET images were analyzed visually and semi-quantitatively by measuring the maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio, lesion-to-blood pool SUVmax ratio and the tumor to normal brain uptake ratio (T/N ratio) and compared with epidemiological (age, sex, HIV infection) and morphological (tumor size, MRI appearance) characteristics. Thirty-eight patients (83%) had positive 18F-FDG PET/CT (average SUVmax was 15.6 ± 9.2; lesion-to-liver SUVmax ratio 5.8 ± 2.8; lesion-to-blood pool SUVmax ratio 7.1 ± 3.8, T/N ratio 3.1 ± 1.7) at the corresponding brain lesion; the remaining 8 (17%) were not 18F-FDG avid. 18F-FDG avidity was significantly associated with morphological appearance and tumor size and not correlated with other features. 18F-FDG PET/CT detected extracranial disease in two cases (4%) with negative bone marrow biopsies and CT. In conclusion, brain lymphomas are 18F-FDG avid in 83% of cases showing high 18F-FDG uptake and 18F-FDG avidity is correlated with tumor size and morphological appearance of the lesion. PET/CT helped to recognize extracranial disease in two patients.

Advances in the treatment of newly diagnosed primary central nervous system lymphomas

Primary central nervous system lymphoma (PCNSL) is a type of highly invasive non-Hodgkin lymphoma. With a growing number of organ transplantation and immunosuppressant therapy, the incidence of PCNSL has been growing rapidly in recent years, which is attributed to the increased incidence of HIV/AIDS, a prominent risk factor for developing PCNSL. The rising rate of PCNSL incidence is the highest among the intracranial tumors. In the past 20 years, dozens of clinical trials related to PCNSL have been registered, but adequate therapeutics are still challenging. Currently, the chemotherapy regimens based on high-dose methotrexate and whole-brain radiotherapy are the two main therapeutic options; however, the toxicity associated with those is the main problem that challenges medical researchers. Novel agents and therapeutic strategies have been developed in recent years. In the current review, we describe advances in the treatment of PCNSL and discuss novel therapeutic approaches currently in development, such as the use of rituximab, disruption of the blood-brain barrier, and state-of-the-art radiotherapy.

A clinicopathological study of primary central nervous system lymphomas & their association with Epstein-Barr virus

Background & objectives:

Primary central nervous system lymphomas (PCNSLs) are relatively uncommon, accounting for 2-3 per cent of primary brain tumours. Majority of these are diffuse large B cell lymphomas (DLBCL) occurring both in immunocompromised and immunocompetent patients. We undertook this study to classify PCNSL into germinal centre (GC) and non-germinal centre (NGC) type based on Hans classification and to find the role of Epstein-Barr virus (EBV) in pathogenesis both by conventional immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH).

Methods:

The consecutive cases of PCNSL during a 10 years period were analysed by IHC for CD45, CD20, CD3, B-cell lymphoma 2 and 6 (Bcl-2 and Bcl-6), B-cell specific octamer binding protein-1 (BOB-1), multiple myeloma oncogene-1 (MUM-1), EBV latent-membrane protein 1 (LMP-1), cyclin-D1, CD10, CD5 and CD23, as well as by CISH for EBV.

Results:

During a period of 10 years, 65 PCNSL were diagnosed which comprised 0.69 per cent (65/9476) of all intracranial tumours. The mean age of presentation was 49 yr with sex ratio (M:F) of 1.4:1. Most common location was supratentorial region with predominant involvement of frontal lobe. Single lesions were seen in 38 (58.4%) and multifocal lesions in 27 (41.5%) patients. None of the patients were immunocompromised. All cases were B cell immunophenotype and were DLBCL except one case of follicular lymphoma. According to Hans classification, majority of them were NGC (n=51, 79.6%) and 13 (20.3%) were GC type. Bcl-2 expression was noted in 34 (52.3%) tumours. EBV was positive in three (4.6%) cases; two were detected both by IHC and CISH and one case by CISH only.

Interpretation & conclusions:

In Indian population, PCNSL occurs mainly in immunocompetent patients, and a decade earlier than in western population. Immunophenotyping revealed that all cases were DLBCL with predominance of NGC type. No prognostic difference was seen between GC and NGC DLBCL. Association of EBV was rare and this virus was possibly not involved in the pathogenesis of PCNSL in immunocompetent individuals. CISH was an easy, economical and less cumbersome method for detection of EBV in PCNSL.

Clinicopathological Features and Outcomes in Primary Central Nervous System Lymphoma: A 10-year Experience

Context

Primary central nervous system lymphoma (PCNSL) is a variant of extranodal lymphoma, accounting for 4% of primary central nervous system tumors. PCNSL was more common in immunocompetent individuals. International Extranodal Lymphoma Study Group (IELSG) scoring was used for prognostication. High-dose methotrexate regimens along with radiotherapy improved outcomes in PCNSL.

Aims

The aim of this study is to analyze the clinical and pathological features, progression-free survival (PFS), and overall survival (OS) in patients with PCNSL.

Materials and Methods

Data of patients with PCNSL between 2005 and 2016 were retrospectively analyzed. Outcome was analyzed in patients who received chemotherapy. GraphPad Prism software for Windows Version 6 was used to plot the Kaplan-Meier curves for PFS and OS. Log-rank test was used to calculate P values. P < 0.05 was considered as statistically significant.

Results

A total of 42 patients were available for analysis. Of these, 34 patients who received chemotherapy were evaluable for outcome parameters. The median age at presentation was 46 years (range, 10-75) with male-to-female ratio of 2.2:1. Only 2 (4.7%) patients were HIV positive. Diffuse large B-cell lymphoma (DLBCL) was the most common histology seen in 41 (97.6%) patients. Using IELSG risk scoring, scores of 8 (19%), 19 (45.2%), and 15 (35.8%) were stratified into low, intermediate, and high risk. The median PFS and OS were 11 months (range, 2-72) and 15.9 months (2.4-80.4), respectively. The median OS was 36.2 months (range, 8.8-72), 15.6 months (2-36), and 6.1 months (2.6-12.7) in low-, intermediate-, and high-risk groups, respectively, which was statistically significant (P = 0.0002).

Conclusions

Immunocompetent patients with PCNSL outnumber immunocompromised patients. DLBCL was the most common histology, and IELSG risk stratification significantly predicts the outcome in PCNSL.

Linfoma del sistema nervoso centrale in corso di AIDS

Il linfoma primitivo cerebrale (LPC) è la più comune delle neoplasie opportunistiche del SNC in pazienti AIDS, seguito dal linfoma di Kaposi e dai gliomi, e spesso rappresenta la patologia rivelatrice della condizione di immunodeficienza acquisita.

L'incidenza dei LPC è in costante aumento nelle ultime due decadi. Attualmente rappresentano il 6,6–15,4% di tutti i tumori cerebrali primitivi contro il 3,3% registrato prima del 1978. Nei pazienti AIDS, ha una frequenza compresa fra il 3% ed il 10%. Si tratta, peraltro, di una patologia ancora relativamente rara costituendo solo lo 0,7–0,9% di tutti i linfomi.

I LPC si localizzano in prevalenza in regione sopratentoriale (90%) specialmente nella sostanza grigia periventricolare e nella sostanza bianca; la localizzazione in fossa cranica posteriore è stimata intorno al 10%. Nel LPC l'interessamento leptomeningeo non è comune riscontrandosi in circa il 12% dei casi; più raro il coinvolgimento durale, rarissimo (circa 1%) il coinvolgimento del midollo spinale. Viceversa il linfoma secondario tende ad invadere la dura madre e le leptomeningi.

Il LPC in corso di AIDS si manifesta in forma multifocale fra il 50 ed il 75%.

Dal 1991 è stata documentata una quasi costante associazione del virus di Ebstein-Barr (EBV) con il LPC il che ha indotto a considerare la possibilità di usare l'EBV come un marker diagnostico di tale patologia.

La costante presenza del EBV nel LPC in immunodepressi è in contrasto con quanto visto negli immunocompetenti ove l'associazione è modesta.

Ad una valutazione macroscopica il LPC si manifesta come massa nodulare con consistenza molto variabile da friabile a solida e superficie granulare. La lesione è frequentemente circondata da edema, comunemente diffonde alla leptomeninge e alle regioni subpiali. È multifocale nel 11–50% dei pazienti immunocompetenti e nel 41–81% dei pazienti AIDS nei quali peraltro l'incidenza di multifocalità può raggiungere il 100%.

All'analisi istologica il LPC mostra strati uniformi di cellule neoplastiche, strettamente stipate; il processo di infiltrazione si diffonde ben oltre i margini macroscopici della lesione. Necrosi ed emorragie sono molto più frequenti nei pazienti immunocompromessi.

Neuroradiologicamente le lesioni risultano tipicamente iperdense alla TC e questo aspetto è attribuito ad un alto rapporto nucleo-citoplasma ed ad un elevata cellularità fittamente stipata. Dopo mdc praticamente tutti i LPC mostrano impregnazione la cui intensità è peraltro variabile e talora così debole e indefinita da non essere apprezzata se non utilizzando appropriate finestre.

In RM nelle immagini T1 la lesione è tipicamente da ipo- ad isointensa relativamente alla sostanza grigia e produce un effetto massa modesto rispetto alle sue dimensioni.

Nei primi riferimenti della letteratura tali lesioni erano descritte quasi uniformemente iperintense in T2. Più recentemente, e probabilmente in rapporto ad un affinamento del software che ha consentito una maggiore evidenza di fini dettagli, le lesioni si documentano prevalentemente iso-ipointense alla sostanza grigia in T2, aspetto che, come alla TC, riflette l'alto rapporto nucleo- citoplasma e l'elevata cellularità fittamente stipata.

Nella popolazione non AIDS il LPC mostra quasi costantemente alla RM un impregnazione dopo mdc che risulta omogeneo nei 2/3 dei casi.

Nella popolazione AIDS il LPC mostra impregnazione nel 100% dei casi che risulta disomogeneo nel 54% dei casi, con un pattern anulare nel 46% ed uno irregolare nell '8%.

Uno degli aspetti caratteristici del LPC è la tendenza a diffondere lungo l'ependima, le meningi o entrambe. Questa dtffusione è documentata in percentuali variabili che raggiungono il 75% e si attestano al 28% per la contiguità con la superficie ependimale e 1′8% per la contiguità con la meninge.

Starry Sky Pattern in Hematopoietic Neoplasms: A Review of Pathophysiology and Differential Diagnosis

The starry sky pattern is a distinctive histologic feature wherein a rapidly proliferating hematolymphoid neoplasm contains scattered histiocytes with abundant pale cytoplasm in a background of monomorphic neoplastic cells. The cytoplasm of these histiocytes typically contains cellular remnants, also known as tingible bodies, incorporated through active phagocytosis. Although common and widely recognized, relatively little is known about the pathophysiological underpinnings of the starry sky pattern. Its resemblance to a similar pattern seen in the germinal centers of secondary follicles suggests a possible starting point for understanding the molecular basis of the starry sky pattern and potential routes for its exploitation for therapeutic purposes. In this review, we discuss the historical, pathophysiological, and clinical implications of the starry sky pattern.

The Influence of Corticosteroids on Diagnostic Accuracy of Biopsy for Primary Central Nervous System Lymphoma

Classical neurosurgical teaching suggests that corticosteroid administration reduces the diagnostic yield of stereotactic brain biopsy for primary central nervous system lymphoma (PCNSL). In a single-center series spanning 6 years, we reviewed 155 consecutive biopsy patients, 135 treated with prebiopsy corticosteroids. PCNSL was correctly diagnosed on initial biopsy in 15 of 16 steroid-treated patients; in the single nondiagnostic specimen, polymerase chain reaction reanalysis by an outside institution showed evidence of lymphoproliferative disease consistent with PCNSL. Our data challenge the notion that it is necessary to withhold corticosteroid therapy for cerebral edema in patients awaiting stereotactic biopsy for suspected PCNSL.

Diffusional kurtosis imaging for differentiating between high-grade glioma and primary central nervous system lymphoma

BACKGROUND

The aim of this study was to assess the diagnostic accuracy of diffusion kurtosis magnetic resonance imaging parameters for differentiating high-grade gliomas (HGGs) from primary central nervous system lymphomas (PCNSLs).

METHODS

Diffusion parameters, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ// ), radial diffusivity (λ⊥ ); and kurtosis parameters, including mean kurtosis (MK), axial kurtosis (K// ), and radial kurtosis (K⊥ ), were normalized to contralateral normal-appearing white matter (NAWMc) to decrease inter-individual and inter-regional changes across the entire brain, and then compared with the solid parts of 20 HGGs and 11 PCNSLs [median 95% confidence interval (CI), P < 0.004; 0.05/14], significance level, Kolmogorov-Smirnov test, Bonferroni correction].

RESULTS

FA, MD, λ// , and λ⊥ values were higher in HGGs than in PCNSLs, but not significantly [HGGs: 0.209 (95% CI, 0.134-0.338), 1.385 (95% CI, 1.05-1.710), 1.655 (95% CI, 1.30-2.060), 1.228 (95% CI, 0.932-1.480), respectively; PCNSLs: 0.143 (95% CI, 0.110-0.317), 1.070 (95% CI, 0.842-1.470), 1.260 (95% CI, 0.960-1.930), 1.010 (95% CI, 0.782-1.240)], respectively; P = 0.120, 0.010, 0.004, and 0.004, respectively). However, MK and K// were significantly higher in PCNSLs compared with HGGs [PCNSLs: 0.765 (95% CI, 0.697-0.890), 0.787 (95% CI, 0.615-1.030), respectively; HGGs: 0.531 (95% CI, 0.402-0.766), 0.532 (95% CI, 0.432-0.680], respectively; P = 0.001, 0.000, respectively); but not K⊥ [0.774 (95% CI, 0.681-0.899) for PCNSLs; 0.554 (95% CI, 0.389-0.954) for HGGs; P = 0.024].

CONCLUSION

There were significant differences in kurtosis parameters (MK and K// ) between HGGs and PCNSLs, while differences in diffusion parameters between them did not reach significance; hence, better separation was achieved with these parameters than with conventional diffusion imaging parameters. J. Magn. Reson. Imaging 2016;44:30-40.

Primary Central Nervous System Lymphoma: A Critical Review of the Role of Surgery for Resection

BACKGROUND

Primary central nervous system lymphomas (PCNSL) are rare CNS tumors that carry a poor prognosis, with most patients suffering recurrence. Progress has been made in the treatment of this pathology, notably with the widespread use of systemic high dose methotrexate. However, unlike most other malignant CNS neoplasms, surgery for cytoreduction is not routinely performed for this disease, mainly as a result of negative experiences decades ago. Since these studies were published, the availability of intraoperative monitoring, MR imaging and neuro-navigation as well as surgical adjuncts such as fluorescence- guided resection have greatly improved the safety of intracranial procedures. More recent data is suggestive of a potential survival benefit for resection of single PCNSL lesions when patients are subsequently treated with modern regimen high-dose methotrexate, yet this evidence is limited, and should be interpreted conservatively.

METHODS AND FINDINGS

A systematic review of the literature was performed to identify trials evaluating surgical options for the treatment of PCNSL.

CONCLUSION

In this review, we provide a critical overview of the evidence favoring and discouraging resection for PCNSL. This literature suffers from several biases and limitations that must be considered in the context of the extrapolation of this literature into clinical decision-making.

Treatment of newly diagnosed B-cell origin primary CNS lymphoma with systemic R-IDARAM chemotherapy and intrathecal immunochemotherapy

Background

Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin's lymphoma (NHL). The aim was to evaluate response rate, progression free survival (PFS), overall survival (OS), and toxicity in PCNSL after systemic R-IDARAM and intrathecal immunochemotherapy with deferred radiotherapy.

Results

The response rate was 94% with 17 (89%) complete responses and 1 (5%) partial responses. Follow-up time is from 5 to 63 months (median, 39 months). Median survival has not been reached. 3-year overall survival and progression-free survival rates were 84.2% (CI 72.6% to 99.8%) and 63.2% (CI 41.4% to 73.8%). Systemic toxicity was mainly hematologic. Neurocognitive and neuromotor deterioration as a result of treatment occurred in only one patient (5%).

Patients and Methods

From September 2010 to June 2015, 19 consecutive patients with PCNSL (median age, 54 years) were enrolled into a pilot phase II study evaluating immunochemotherapy without radiotherapy. The patients were accrued to a chemotherapy regimen that incorporated rituximab, idarubicin, dexamethasone, cytarabine (Ara-c) and methotrexate (MTX) combined with intrathecal rituximab, MTX, dexamethasone and Ara-c.

Conclusions

The results indicate that R-IDARAM regimen with intrathecal immunochemotherapy is generally well tolerated and produces a high complete response rate and survival rate.

Primary CNS T-cell Lymphomas: A Clinical, Morphologic, Immunophenotypic, and Molecular Analysis

Primary central nervous system (CNS) lymphomas are relatively rare with the most common subtype being diffuse large B-cell lymphoma. Primary CNS T-cell lymphomas (PCNSTL) account for <5% of CNS lymphomas. We report the clinical, morphologic, immunophenotypic, and molecular characteristics of 18 PCNSTLs. Fifteen cases were classified as peripheral T-cell lymphoma, not otherwise specified, 2 of which were of γδ T-cell derivation and 1 was TCR silent; there was 1 anaplastic large cell lymphoma, ALK-positive and 2 anaplastic large cell lymphoma, ALK-negative. Median age was 58.5 years (range, 21 to 81 y), with an M:F ratio of 11:7. Imaging results showed that 15 patients had supratentorial lesions. Regardless of subtype, necrosis and perivascular cuffing of tumor cells were frequently observed (11/18 cases). CD3 was positive in all cases but 1; 10/17 were CD8-positive, and 5/17 were CD4-positive. Most cases studied had a cytotoxic phenotype with expression of TIA1 (13/15) and granzyme-B (9/13). Polymerase chain reaction analysis of T-cell receptor γ rearrangement confirmed a T-cell clone in 14 cases with adequate DNA quality. Next-generation sequencing showed somatic mutations in 36% of cases studied; 2 had >1 mutation, and none showed overlapping mutations. These included mutations in DNMT3A, KRAS, JAK3, STAT3, STAT5B, GNB1, and TET2 genes, genes implicated previously in other T-cell neoplasms. The outcome was heterogenous; 2 patients are alive without disease, 4 are alive with disease, and 6 died of disease. In conclusion, PCNSTLs are histologically and genomically heterogenous with frequent phenotypic aberrancy and a cytotoxic phenotype in most cases.

The influence of rituximab, high-dose therapy followed by autologous stem cell transplantation, and age in patients with primary CNS lymphoma

For patients with diffuse large B cell lymphoma without the involvement of the CNS, the addition of rituximab to standard chemotherapy has significantly improved survival. In this single-center, retrospective analysis, a total of 81 primary CNS lymphoma (PCNSL) patients treated in our institution between 2000 and 2011 were included. Beside first-line chemotherapy with or without rituximab, we evaluated the impact of age (≤/>60 years), autologous stem cell transplantation (ASCT +/-), and other factors upon overall survival (OS) and progression-free survival (PFS). In patients treated with rituximab (n = 27), 3-year OS was 77.8 % (95 % confidence interval (CI) 62-93 %). In contrast, in patients treated without rituximab (n = 52), 3-year OS was only 39.9 % (CI 27-53 %, Fig. 1). The difference in OS was significant in the univariate (p = 0.002) as well as in the multivariate analysis (p = 0.049, hazard ratio (HR) = 0.248). Patients ≤60 years of age (n = 28) had a 3-year OS of 78.2 % (CI 63-94 %); in patients >60 years (n = 51), 3-year OS was 38.7 % (CI 25-52 %). Patients who received high-dose therapy and ASCT had a 3-year OS of 85.2 % (CI 72-99 %), and 65.1 % were alive up to the time of analysis (range 9-131 months). Without ASCT, median OS was only 16 months (CI 11-21) and 3-year OS was 35.2 % (CI 22-48 %). Age and ASCT were significantly associated with better OS in univariate (p = 0.002 and p < 0.001) as well in multivariate analysis (p = 0.004, HR = 0.023 and p = 0.001, HR = 0.014). Rituximab treatment, ASCT, and age are independent prognostic factors for OS in the first-line treatment of PCNSL.

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.

Sino-nasal T-cell lymphoma invading the brain: A case study

Lesions occupying the anterior cranial fossa may arise de novo or are extensions from the sino-nasal areas with a handful of differentials in either group. The imaging findings, though to a large extent standardized are not full proof. Primary central nervous system lymphoma and sino-nasal lymphoma are uncommon variants of extranodal non-Hodgkin's lymphoma (NHL). We encountered a 35-year-old lady presenting with headache and seizures with a mass lesion involving the ethmoids with invasion into the anterior cranial fossa diagnosed as T-cell extranodal NHL. Gross total resection and reconstruction of the skull base were done. She was treated with chemotherapy and radiotherapy and is doing well at 6 months follow-up. This is the first report of a sino-nasal T-cell lymphoma invading the brain-parenchyma in an immuno-competent person. Sino-nasal primary T-cell lymphoma presenting as skull base pathology should form an essential differential diagnosis along with other routine lesions of anterior cranial fossa. Since these lesions have a good response to chemo and radiotherapy, a trans-nasal biopsy may obviate the need of a craniotomy if neurosurgeons are aware of this rare entity.

Disseminated encephalomyelitis-like central nervous system neoplasm in childhood

A malignant neoplasm in the central nervous system with diffuse white matter changes on magnetic resonance imaging (MRI) is rare in children. It could be misdiagnosed as acute disseminated encephalomyelitis. This report presents our experience based on 4 patients (3 male, 1 female; aged 7-13 years) whose MRI showed diffuse lesions in white matter and who were initially diagnosed with acute disseminated encephalomyelitis. All of the patients received corticosteroid therapy. After brain biopsy, the patients were diagnosed with gliomatosis cerebri, primitive neuroectodermal tumor and central nervous system lymphoma. We also provide literature reviews and discuss the differentiation of central nervous system neoplasm from acute disseminated encephalomyelitis.

[Leptomeningeal infiltlation of primary CNS B-cell lymphoma diagnosed by the biopsy of cauda equina: a case report]

A 49-year-old man was admitted to our hospital with progressive gait disturbance. Our examination revealed a low grade fever, weight loss derived muscle weakness, sensory disturbance and loss of deep tendon reflex of the lower extremities. Magnetic resonance imaging (MRI) detected an abnormal intensity and gadolinium enhancement in the cauda equina. Two weeks after admission, disturbance of consciousness and bladder appeared. Cerebrospinal fluid examination showed pleocytosis, elevated protein and soluble IL-2R, but cytological examination was class II negative. We performed a cauda equina biopsy urgently and diagnosed malignant lymphoma, of a diffuse large B-cell type. We selected combined MTX-based chemoradiotherapy and his symptoms significantly improved after a month. He achieved complete remission and remains recurrence-free after 10 months post treatment although he remains with light paraparesis and sensory disturbance of the lower extremities. He has already gone back to a normal life. An examination of cauda equina biopsy led to quick diagnosis and treatment.