How I treat primary CNS lymphoma

Impact of Methotrexate and 7-Hydroxymethotrexate Exposure on Renal Toxicity in Pediatric Non-Hodgkin Lymphoma

BACKGROUND

7-Hydroxymethotrexate (7-OHMTX) is the main metabolite in plasma following high-dose MTX (HD-MTX), which may result in activity and toxicity of the MTX. Moreover, 7-OHMTX could produce crystalline-like deposits within the renal tubules under acidic conditions or induce renal inflammation, oxidative stress, and cell apoptosis through various signaling pathways, ultimately leading to kidney damage. The objectives of this study were thus to explore the exposure-safety relationship of two compounds and search the most reliable marker for predicting HDMTX nephrotoxicity.

METHOD

A total of 280 plasma concentration data (140 for MTX and 140 for 7-OHMTX) for 60 pediatric patients with non-Hodgkin lymphoma (NHL) were prospectively collected. Plasma MTX and 7-OHMTX concentrations were determined using a high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method. A nonlinear mixed effect model approach was used to build a joint population pharmacokinetic (PopPK) model. After validation, the model estimated the peak concentration (Cmax) and area under the curve within the initial 48 h (AUC0-48h) of the patients after drug administration by Bayesian feedback. The receiver operating characteristic (ROC) curves were generated to identify an exposure threshold associated with nephrotoxicity.

RESULTS

A three-compartment chain model (central and peripheral compartments for MTX and central compartment 7-OHMTX) with the first-order elimination adequately characterized the in vivo process of MTX and 7-OHMTX. The covariate analysis identified that the aspartate aminotransferase (AST) was strongly associated with the peripheral volume of distribution of MTX. Moreover, the Cmax of MTX and 7-OHMTX showed significant differences (p < 0.0001, p = 0.0472, respectively) among patients with or without nephrotoxicity. Similarly, individuals with nephrotoxicity also exhibited substantially higher ratio of 7-OHMTX to MTX peak concentration and the sum of MTX + 2.25 times the concentration of 7-OHMTX (p < 0.0001, p = 0.0426, respectively). By ROC analysis, the Cmax of MTX and 7-OHMTX had the greatest area under the curve (AUC) values (0.769 and 0.771, respectively). A Cmax threshold of 9.26 μmol/L for MTX or a Cmax threshold of 0.66 μmol/L for 7-OHMTX was associated with the best sensitivity/specificity for toxicity events (MTX: sensitivity = 0.886; specificity = 0.70; 7-OHMTX: sensitivity = 0.886; specificity = 0.70).

CONCLUSIONS

We demonstrated that the Cmax of MTX and 7-OHMTX were the most reliable markers associated with nephrotoxicity and proposed a Cmax threshold of 9.26 μmol/L for MTX and 0.66 μmol/L for 7-OHMTX as the point with a high risk of nephrotoxicity. Altogether, this study may contribute to crucial insights for ensuring the safe administration of drugs in pediatric clinical practice.

Cerebrospinal fluid IL-6 and IL-10 as promising diagnostic and therapeutic prognostic biomarkers for secondary central nervous system lymphoma

BACKGROUND

Accurate diagnosis and therapeutic response to secondary central nervous system lymphoma (SCNSL) are challenges that need to be addressed. We assessed the value of cerebrospinal fluid (CSF) cytokine levels for diagnosis and post-therapeutic prognosis in patients with SCNSL.

METHODS

This retrospective study included 234 patients with non-Hodgkin lymphoma (NHL), including the SCNSL group (n = 57) and the non-SCNSL group (n = 177). The Mann-Whitney U test was used to compare the cytokine profiles between SCNSL and non-SCNSL group. Receiver operating characteristic curve was used to determine the diagnostic ability of CSF cytokine levels for SCNSL. The predictive value of CSF cytokine concentrations for progression free survival of patients with SCNSL was evaluated using a log-rank test.

RESULTS

CSF IL-6 and IL-10 levels in SCNSL group were significantly elevated compared with those in the other two groups. ROC curve showed that the cutoff values of IL-6 and IL-10 in CSF were 10.13 pg/ml and 7.82pg/ml, which yielded the diagnostic sensitivity were 62.34% and 76.23%, specificity were 87.57% and 88.31%, respectively. Furthermore, combining CSF IL-6 and IL-10 levels significantly improved the diagnostic efficacy. CSF IL-6 and IL-10 levels in SCNSL patients in complete remission under chemotherapy were significantly reduced. In addition, poor progression free survival (PFS) in patients with SCNSL was related to increased CSF IL-10 levels at diagnosis, but not with increased CSF IL-6 levels.

CONCLUSION

CSF IL-6 and IL-10 levels are promising biomarkers for diagnosis and predictors of response for SCNSL.

Comparative analyses of immune cells and alpha-smooth muscle actin-positive cells under the immunological microenvironment between with and without dense fibrosis in primary central nervous system lymphoma

Histopathologic examinations of primary central nervous system lymphoma (PCNSL) reveal concentric accumulation of lymphocytes in the perivascular area with fibrosis. However, the nature of this fibrosis in "stiff" PCNSL remains unclear. We have encountered some PCNSLs with hard masses as surgical findings. This study investigated the dense fibrous status and tumor microenvironment of PCNSLs with or without stiffness. We evaluated by silver-impregnation nine PCNSLs with stiffness and 26 PCNSLs without stiffness. Six of the nine stiff PCNSLs showed pathological features of prominent fibrosis characterized by aggregation of reticulin fibers, and collagen accumulations. Alpha-smooth muscle actin (αSMA)-positive spindle cells as a cancer-associated fibroblast, the populations of T lymphocytes, and macrophages were compared between fibrous and control PCNSLs. Fibrous PCNSLs included abundant αSMA-positive cells in both intra- and extra-tumor environments (5/6, 87% and 3/6, 50%, respectively). Conversely, only one out of the seven control PCNSL contained αSMA-positive cells in the intra-tumoral area. Furthermore, the presence of extra-tumoral αSMA-positive cells was associated with infiltration of T lymphocytes and macrophages. In conclusion, recognizing the presence of dense fibrosis in PCNSL can provide insights into the tumor microenvironment. These results may help stratify patients with PCNSL and improve immunotherapies for these patients.

Targets and treatments in primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive lymphoma entirely localized in the central nervous system or vitreoretinal space. PCNSL generally initially responds to methotrexate-containing chemotherapy regimens, but progressive or relapsing disease is common, and the prognosis is poor for relapsed or refractory (R/R) patients. PCNSL is often characterized by activation of nuclear factor kappa B (NF-κB) due to mutations in the B-cell receptor (BCR) or toll-like receptor (TLR) pathways, as well as immune evasion. Targeted treatments that inhibit key PCNSL mechanisms and pathways are being evaluated; inhibition of Bruton's tyrosine kinase (BTK) downstream of BCR activation has demonstrated promising results in treating R/R disease. This review will summarize the evidence and potential for targeted therapeutic agents to improve treatment outcomes in PCNSL. This includes immunotherapeutic and immunomodulatory approaches and inhibitors of the key pathways driving PCNSL, such as aberrant BCR and TLR signaling.

Clinical and Genomic Profile of Primary Cranial Neurolymphomatosis

Primary cranial neurolymphomatosis (PCNL) is a rare subtype of primary CNS lymphoma (PCNSL) in which infiltrative lymphomatous involvement is confined to cranial nerves. Here, we report a case of PCNL with successful genomic profiling. A 57-year-old male had a lengthy prediagnostic phase spanning approximately 30 months, characterized by multiple episodes of cranial neuropathies managed by steroids. At the time of diagnosis, the patient had right-sided cranial neuropathies involving cranial nerves (CN) V, VI, and VII. Pathological findings of the right cavernous lesion biopsy were consistent with large B-cell lymphoma-infiltrating nerve fibers. The clinical course was aggressive and refractory, characterized by relentless progression with the development of cervical spinal neurolymphomatosis, cerebrospinal fluid involvement, and ependymal and intraparenchymal cerebral involvement, despite multiple lines of therapy, including chemoimmunotherapy, Bruton's tyrosine kinase inhibitor, radiation, autologous stem cell transplant, chimeric antigen receptor T-cell therapy (CAR-T), and whole-brain radiation. The patient survived for 22 months from the time of the initial diagnosis and 52 months after the first episode of cranial neuropathy. Next-generation sequencing identified mutations (MYD88, CD79b, and PIM1) that are frequently observed in PCNSL. The unusual findings included a total of 22 mutations involving PIM1, indicating a highly active aberrant somatic hypermutation and two missense CXCR4 mutations. CXCR4 mutations have never been described in PCNSL and may have implications for disease biology and therapeutic interventions. We provide a literature review to further elucidate PCNL.

Use of fluorescein sodium to obtain histological diagnosis of primary Central nervous system lymphoma ghost tumour despite disappearance on intraoperative magnetic resonance imaging: technical note and review of the literature

BACKGROUND AND IMPORTANCE

Corticosteroid pre-treatment in patients with primary central nervous system lymphoma (PCNSL) can lead to the phenomenon of ghost tumours (GhT). This affects the diagnostic yield of biopsies and potentially causes misdiagnosis of the condition. The usual strategy of neuronavigation using preoperative magnetic resonance imaging (MRI) or localisation using intraoperative MRI (iMRI) can be rendered ineffective in this situation.

CLINICAL PRESENTATION

A middle-aged Chinese male with newly diagnosed human immunodeficiency virus infection was found to have an intracranial lesion suggestive of PCNSL. Preoperatively corticosteroid led to an attenuation of the contrast enhancing lesion on iMRI. However, intraoperative use of FS allowed the successful identification, biopsy and diagnosis of the condition.

CONCLUSION

FS is useful in the biopsy of PCNSL GhT even when the lesion is not seen in subsequent MRI imaging.

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.

Absence of enhancement in a lesion does not preclude primary central nervous system T-cell lymphoma: A case report

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a non-Hodgkin lymphoma that originates in the central nervous system (CNS) and is exclusively limited to the CNS. Although most PCNSLs are diffuse large B-cell lymphomas, primary CNS T-cell lymphomas (PCNSTLs) are rare. PCNSTLs typically demonstrate some degree of enhancement on contrast-enhanced magnetic resonance imaging (MRI). To the best of our knowledge, non-enhancing PCNSTL has not been reported previously.

CASE SUMMARY

A 69-year-old male presented to the neurology department with complaints of mild cognitive impairment and gradual onset of left lower leg weakness over a span of two weeks. Initial MRI showed asymmetric T2-hyperintense lesions within the brain. No enhancement was observed on the contrast-enhanced T1 image. The initial diagnosis was neuro-Behçet's disease. Despite high-dose steroid therapy, no alterations in the lesions were identified on initial MRI. The patient's symptoms deteriorated further. An MRI performed one month after the initial scan revealed an increased lesion extent. Subsequently, brain biopsy confirmed the diagnosis of PCNSTL. The patient underwent definitive combined chemo-radiotherapy. However, the patient developed bacteremia and died of septic shock approximately three months after diagnosis.

CONCLUSION

The absence of enhancement in the lesion did not rule out PCNSTL. A biopsy approach is advisable for pathological confirmation.

Three-year follow-up analysis of phase 1/2 study on tirabrutinib in patients with relapsed or refractory primary central nervous system lymphoma

Background

The ONO-4059-02 phase 1/2 study showed favorable efficacy and acceptable safety profile of tirabrutinib, a second-generation Bruton's tyrosine kinase inhibitor, for relapsed/refractory primary central nervous system lymphoma (PCNSL). Here, we report the long-term efficacy and safety after a 3-year follow-up.

Methods

Eligible patients were aged ≥ 20 years with histologically diagnosed PCNSL and KPS of ≥ 70. Patients received oral tirabrutinib once daily at 320 or 480 mg, or 480 mg under fasted conditions.

Results

Between October 19, 2017, and June 13, 2019, 44 patients were enrolled: 33 and 9 had relapsed and refractory, respectively. The 320, 480, and 480 mg fasted groups included 20, 7, and 17 patients, respectively. The median follow-up was 37.1 months. The overall response rate was 63.6% (95% CI: 47.8-77.6) with complete response (CR), unconfirmed CR, and partial response in 9, 7, and 12 patients, respectively. The median duration of response (DOR) was 9.2 months, with a DOR rate of 19.8%; the median progression-free survival (PFS) and median overall survival (OS) were 2.9 months and not reached, respectively, with PFS and OS rates of 13.9% and 56.7%, respectively. Adverse events occurred in 38 patients (86.4%): grade ≥ 3 in 23 (52.3%) including 1 patient with grade 5 events. KPS and quality of life (QoL) scores were well maintained among patients receiving long-term treatment.

Conclusions

The results demonstrated the long-term clinical benefit of tirabrutinib, with deep and durable response in a subset of patients and acceptable safety profile, while KPS and QoL scores were maintained.

Preclinical and clinical evaluation of Buparlisib (BKM120) in recurrent/refractory Central Nervous System Lymphoma

Central Nervous System (CNS) Lymphomas are aggressive brain tumors with limited treatment options. Targeting the phosphoinositide 3-kinase (PI3K) pathway yields promising responses across B-cell malignancies, but its therapeutic potential in CNS lymphomas remains unexplored. We present pre-clinical and clinical data on the pan-PI3K inhibitor Buparlisib in CNS lymphomas. In a primary CNS lymphoma-patient-derived cell line, we define the EC50. Four patients with recurrent CNS lymphoma were enrolled in a prospective trial. We evaluated Buparlisib plasma and cerebrospinal fluid pharmacokinetics, clinical outcomes, and adverse events. Treatment was well tolerated. Common toxicities include hyperglycemia, thrombocytopenia, and lymphopenia. The presence of Buparlisib in plasma and CSF was confirmed 2h post-treatment with a median CSF concentration below the EC50 defined in the cell line All four patients were evaluated for response and the median time to progression was 39 days. Buparlisib monotherapy did not lead to meaningful responses and the trial was prematurely stopped.Clinical Trial Registration: NCT02301364.

A Case of Relapsed Primary Central Nervous System Lymphoma Treated with CD19-directed Chimeric Antigen Receptor T Cell Therapy

Although high-dose methotrexate (HD-MTX) is the standard therapy for primary central nervous system lymphoma (PCNSL), the prognosis remains poor. Because 90% of PCNSL is diffuse large B-cell lymphoma (DLBCL), chimeric antigen receptor (CAR)-T cell therapy is expected to be beneficial. However, there are limited reports on CAR-T cell therapy for PCNSL because of the concern of neurotoxicity. Here, we report a case of relapsed PCNSL treated with anti-CD19 CAR-T cell therapy. A 40-year-old woman presenting with visual disturbance in her left eye was initially diagnosed with bilateral uveitis. Her histological diagnosis was DLBCL, and she was positive for CD19. Although she received chemotherapy including HD-MTX, the tumor relapsed in her right occipital lobe. She underwent remission induction therapy and then anti-CD19 CAR-T cell therapy. Cytokine release syndrome (CRS) grade 2 occurred, but there were no complications of CAR-T cell-related encephalopathy syndrome (CRES). She has achieved complete response for more than 1 year. Anti-CD19 CAR-T cell therapy is a revolutionary immunotherapy for treating relapsed or refractory (R/R) B lineage malignancies. Although there are concerns regarding CRS and CRES in central nervous system lymphoma, the use of anti-CD19 CAR-T cells to treat R/R PCNSL is safe and feasible.

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.

Systemic Relapse in a Young Adult Patient with Primary CNS Diffuse Large B-Cell Lymphoma

Primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL) is a rare form of non-Hodgkin's lymphoma, characterized by an aggressive disease course. While CNS relapse is common, systemic relapse is rare with no consensus on optimal treatment. This paper presents an unusual case of advanced PCNS-DLBCL with systemic relapse, including adrenal gland involvement. A review of the existing literature and a discussion on the management of systemic relapse in PCNS-DLBCL is also provided.

Whole-Genome/Exome Sequencing Uncovers Mutations and Copy Number Variations in Primary Diffuse Large B-Cell Lymphoma of the Central Nervous System

Background/objective: Identification of key genetic alterations is of importance in the targeted therapies of primary central nervous system lymphoma (PCNSL). However, only a small number of studies have been carried out in PCNSL. In this study, we further described the genetic mutations and copy number variations (CNVs) in PCNSL patients using whole-genome/exome sequencing (WGS/WES), as well as revealed their associations with patients’ clinicopathological features and prognosis.

Methods: Tumor specimens from 38 patients with primary diffuse large B-cell lymphoma of the central nervous system (CNS DLBCL) were enrolled to WGS (n = 24) or WES (n = 14). The CNVs and mutations of 24 samples (WGS) and 38 samples (WGS/WES) were characterized, respectively. The associations between CNVs and mutations with the overall survival rates of PCNSL patients were also evaluated.

Results: The most common mutations were identified in IGLL5 (68%), PIM1 (63%), MYD88 (55%), CD79B (42%), BTG2 (39%), PCLO (39%), KMT2D (34%), and BTG1 (29%) genes. Among the mutated genes, EP300, ETV6, and HIST1H1E mutations were exclusively detected in the elderly, while DUSP2 mutations were associated with the immune microenvironment indicators. In addition, KMT2D mutation was associated with a poor prognosis. In addition, 488 CNVs including 91 gains and 397 deletions were observed across 24 samples from WGS results. Notably, 1q31.3 amplification was closely associated with the poor prognosis of PCNSL patients.

Conclusion: This study further characterizes the genomic landscape of primary CNS DLBCL using WGS/WES, which provides insight into understanding the pathogenesis of PCNSL and fosters new ideas for the targeted treatment of PCNSL.

Role of upfront autologous stem cell transplantation in patients newly diagnosed with primary CNS lymphoma treated with R-MVP: real-world data from a retrospective single-center analysis

The role of upfront autologous stem cell transplantation (ASCT) remains unclear in patients with primary central nervous system lymphoma (PCNSL) receiving rituximab and high-dose methotrexate (MTX)-based chemotherapy. We analyzed the outcomes of upfront ASCT in 106 patients with PCNSL (median age, 64 years; range, 34-86) who received rituximab, MTX, vincristine, and prednisolone (R-MVP). The objective response rate was 88.7% (94/106) and included 46 complete responses (43.4%). Upfront ASCT was performed in 38 responders (median age, 51 years; range, 34-69), including 13 patients aged >60 years, after conditioning with busulfan (3.2 mg/kg, days 8 to 5) and thiotepa (5 mg/kg, days 4-3). For 56 responders ineligible for ASCT because of age >70 years, poor performance status, or refusal to undergo upfront ASCT, other consolidation treatments (n = 32) or observation (n = 24) were performed. With a median follow-up of 24.4 months (95% confidence interval, 20.7-28.0 months), no transplantation-related deaths occurred and seven patients relapsed after upfront ASCT. By contrast, 24 relapses occurred in patients who did not receive upfront ASCT. The progression-free and overall survival were significantly better in patients undergoing upfront ASCT (P = 0.001). Our real-world data suggest the benefit from upfront ASCT.

Revisiting the concept of recurrence of primary CNS lymphomas after complete response to methotrexate-based therapy: Periventricular reseeding as the predominant mechanism of recurrence

Purpose

Understanding patterns of relapse for primary central nervous system lymphoma (PCNSL) may inform mechanisms of recurrence and optimal consolidation strategies. In this study, we report patterns of relapse among patients with PCNSL who achieved a complete response to high-dose methotrexate (HD-MTX)-based chemotherapy with or without consolidation radiation therapy (RT).

Methods and Materials

We conducted an institutional retrospective analysis of patients with PCNSL who received HD-MTX-based chemotherapy between November 2001 and May 2019. Relapses were characterized as in-field (within original T1 contrasted lesion), marginal (within T2 fluid-attenuated inversion recovery but not T1), local (in-field or marginal), distant brain (no overlap), or distant (distant brain, cerebrospinal fluid, vitreous or extra-axial) and further characterized with respect to periventricular location (≤10 mm of ventricles).

Results

Seventy-eight patients with PCNSL met inclusion criteria, of whom 29 (37%) underwent consolidation RT. Median progression-free survival and overall survival were 57.0 and 66.7 months, respectively. After a median follow-up of 38.9 months, a total of 32 patients (41%) experienced recurrence. Most patients (21 [65.6%]) had a periventricular failure. Surprisingly, local recurrences (n = 11) were exclusively observed within periventricular lesions, whereas distant recurrences (n = 21) were seen in both periventricular and nonperiventricular locations (P = .009). The median time to progression was shorter for locally recurrent lesions compared with distant recurrences (13.8 vs 26.1 months; P = .03).

Conclusions

After complete response to HD-MTX, few failures occurred within initial T1 contrast-enhancing lesions and many of these may have been alternatively classified as periventricular failures. These observations argue against the use of purely focal RT consolidation for patients who achieve a complete response after HD-MTX-based chemotherapy and suggest that periventricular reseeding may have a central role in PCNSL recurrence.

Central Nervous System Lymphoma: Novel Therapies

OPINION STATEMENT

Primary central nervous system lymphomas (PCNSLs) are very rare neoplasms and continue to be challenging to treat. While high-dose methotrexate (HD-MTX)-based regimens are the currently accepted standard first-line therapy for newly diagnosed patients, the optimal induction therapies are still unknown. The role of consolidation therapies continues to evolve with a variety of chemotherapy regimens, including high-dose chemotherapy with stem cell rescue and reduced or deferred whole brain radiotherapy being used. Importantly, several recent advances have been made in the treatment of PCNSL. The incorporation of targeted therapy and immune therapy remain promising strategies. Several agents, successfully used in treatment of systemic lymphomas, have shown activity in PCNSL, frequently leading to durable responses in the relapsed/refractory patients. Many ongoing studies will likely lead to a better understanding of the roles of these treatments, especially as the first line and potentially also as maintenance. In addition, the use of molecular profiling to predict disease response to targeted agents and understand relapse patterns will become increasingly important. Clinical trials in PCNSL are critical yet frequently challenging to conduct given the rarity of the condition and lack of suitable subjects. Therefore, multi-institutional and international collaboration is of utmost importance to accelerate progress in understanding the biology and design better treatments for this disease. It is critical to consider patients of all demographics in the design and study of future treatment algorithms to have the largest impact on patient care and outcomes.

Unusual primary central nervous system T-cell/histiocyte-rich large B-cell lymphoma: a case report

We report the case of a 54-year-old immunocompetent woman who presented with a primary T-cell/histiocyte-rich large B-cell lymphoma (TCHRLBCL) of the central nervous system without systemic involvement, diagnosed by means of a brain biopsy. She was treated with corticosteroids and we subsequently started chemotherapy with rituximab, methotrexate, ifosfamide and intrathecal cytarabine. The patient's symptoms gradually improved over the first weeks and we followed-up with autologous haematopoietic cell transplantation. The patient has been in complete remission for a year. Primary TCHRLBCL of the central nervous system in an immunocompetent patient is an extremely rare condition that requires a multidisciplinary approach. This case highlights the importance of undergoing a sequential work-up and establishing a treatment despite the absence of evidence-based guidelines.

R-MPV followed by high-dose chemotherapy with thiotepa-based and autologous stem cell transplantation for newly diagnosed primary central nervous system lymphoma: a single-center experience

Background

High-dose chemotherapy followed by autologous stem cell transplantation (HDC-ASCT) as a consolidation treatment is a promising approach for eligible patients with newly diagnosed primary central nervous system lymphoma (PCNSL).

Methods

In this retrospective analysis, 22 patients with newly diagnosed PCNSL received chemotherapy with rituximab, methotrexate, procarbazine, and vincristine. Those who showed complete or partial response subsequently received consolidation HDC-ASCT with a thiotepa-based conditioning regimen but did not undergo radiotherapy.

Results

The PCNSL patients had a median age of 57 years (range, 49‒67 yr); of the total patients, 9.1% had a performance status of 2 or higher, and 72.1% had multiple lesions. Approximately 82% of patients received six cycles of induction chemotherapy, which was well tolerated with excellent disease control. The rate of confirmed or unconfirmed complete response increased from 45.5% at the period of interim analysis to 81.8% prior to the initiation of HDC-ASCT. With a median follow-up of 19.6 months (range, 7.5‒56.5 mo), the 2-year progression-free survival and overall survival estimates were 84% and 88%, respectively. No treatment-related deaths occurred. Grade 3 toxicity was recorded in 90.9% of the patients after undergoing the HDC-ASCT, and the most common grade 3 adverse event was febrile neutropenia without sepsis.

Conclusion

The discussed treatment approach is feasible in patients with newly diagnosed PCNSL, yielding encouraging results.

CXCR4-Directed PET/CT with [68Ga]Pentixafor in Central Nervous System Lymphoma: A Comparison with [18F]FDG PET/CT

PURPOSE

This study aimed to evaluate the value of [⁶⁸ Ga]Pentixafor PET/CT for the detection of lesions in central nervous system lymphoma (CNSL) patients before chemotherapy, during treatment and suspected CSNL recurrence, compared with 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) positron emission tomography/computed tomography (PET/CT).

PROCEDURES

Twenty-six patients with newly or previously diagnosed CNSL who underwent [⁶⁸ Ga]Pentixafor PET/CT were included retrospectively. Histopathological results, magnetic resonance imaging (MRI), and follow-up were used as the standard reference. The accuracy of lesion detection, maximum standardized uptake value (SUV_max) of tumors, and ratio of tumor-to-normal brain (T/N) with [⁶⁸ Ga]Pentixafor PET/CT were calculated and compared to those obtained with [¹⁸F]FDG PET/CT. CXCR4 expression was analyzed through immunohistochemistry.

RESULTS

Of 26 patients, 18 were newly diagnosed with a total of 23 lesions, 4 had recurrent with 4 lesions, and 4 underwent a mid-term treatment assessment after 4 cycles of chemotherapy (3 achieved complete response (CR), 1 experienced progressive disease (PD) with a total of 8 lesions). Thirty-five lesions were all clearly detected with favorable contrast by [⁶⁸ Ga]Pentixafor PET/CT (accuracy, 100%), consistent with the results of contrast-enhanced magnetic resonance imaging (CE-MRI). The SUV_max of positive lesions in [⁶⁸ Ga]Pentixafor PET/CT was correlated with tumor size (r = 0.555, P = 0.001). In 21 patients, compared with [¹⁸F]FDG PET/CT, [⁶⁸ Ga]Pentixafor PET/CT showed a remarkably higher T/N ratio (21.93 ± 10.77 vs 4.29 ± 2.16, P = 0.000) and detected 5 more lesions in the mid-term treatment assessment of patients (P = 0.026). The CXCR4 expression of CNSL lesions was correlated with SUV_max of [⁶⁸ Ga]Pentixafor PET/CT (r = 0.772, P = 0.000).

CONCLUSIONS

CXCR4-directed PET/CT using [⁶⁸ Ga]Pentixafor, with excellent tumor-to-background contrast, might be a more promising agent for the detection of lesions in CNSL patients than [¹⁸F]FDG PET/CT.

Artesunate induces apoptosis, autophagy and ferroptosis in diffuse large B cell lymphoma cells by impairing STAT3 signaling

Artesunate (ART), a water-soluble derivative of artemisinin, has been reported to exert antineoplastic effects via diverse mechanisms in various types of cancer. Therefore, understanding the underlying mechanism of action of ART in distinct cancer types is indispensable to optimizing the therapeutic application of ART for different types of cancer. The present study aimed to investigate the cellular and molecular mechanisms responsible for the antineoplastic effects of ART in diffuse large B cell lymphoma (DLBCL) cells. Cell proliferation was measured using Cell Counting Kit-8 and colony formation assays. The levels of apoptosis and cell cycle distribution were investigated using flow cytometry. In addition, western blotting was used to analyze the expression levels of ART-induced apoptosis-, autophagy- and ferroptosis-related proteins. Monodansylcadaverine staining was performed to determine the levels of autophagy. Moreover, malondialdehyde and reactive oxygen species assays were used to determine the levels of ferroptosis. The results of the present study revealed that ART inhibited proliferation, and induced apoptosis, cell cycle arrest, autophagy and ferroptosis in DLBCL cells. Pharmacological inhibition of autophagy and ferroptosis alleviated the increased levels of apoptosis induced by ART. Notably, ART was found to exert its effects via inhibition of STAT3 activation. The genetic knockdown of STAT3 enhanced ART-induced autophagy and ferroptosis, and concomitantly upregulated the expression levels of apoptosis- and cell cycle-related proteins. In conclusion, the findings of the current study suggested that ART may induce apoptosis and cell cycle arrest to inhibit cell proliferation, and regulate autophagy and ferroptosis via impairing the STAT3 signaling pathway in DLBCL cells.

CAR T-Cells for CNS Lymphoma: Driving into New Terrain?

Primary CNS lymphomas (PCNSL) represent a group of extranodal non-Hodgkin lymphomas and secondary CNS lymphomas refer to secondary involvement of the neuroaxis by systemic disease. CNS lymphomas are associated with limited prognosis even after aggressive multimodal therapy. Chimeric antigen receptor (CAR) T-cells have proven as a promising therapeutic avenue in hematological B-cell malignancies including diffuse large B-cell lymphoma, B-cell acute lymphoblastic leukemia, and mantle-cell lymphoma. CARs endow an autologous T-cell population with MHC-unrestricted effectivity against tumor target antigens such as the pan B-cell marker CD19. In PCNSL, compelling and long-lasting anti-tumor effects of such therapy have been shown in murine immunocompromised models. In clinical studies on CAR T-cells for CNS lymphoma, only limited data are available and often include both patients with PCNSL but also patients with secondary CNS lymphoma. Several clinical trials on CAR T-cell therapy for primary and secondary CNS lymphoma are currently ongoing. Extrapolated from the available preliminary data, an overall acceptable safety profile with considerable anti-tumor effects might be expected. Whether these beneficial anti-tumor effects are as long-lasting as in animal models is currently in doubt; and the immunosuppressive tumor microenvironment of the brain may be among the most pivotal factors limiting efficacy of CAR T-cell therapy in CNS lymphoma. Based on an increasing understanding of CAR T-cell interactions with the tumor cells as well as the cerebral tissue, modifications of CAR design or the combination of CAR T-cell therapy with other therapeutic approaches may aid to release the full therapeutic efficiency of CAR T-cells. CAR T-cells may therefore emerge as a novel treatment strategy in primary and secondary CNS lymphoma.

Current and emerging therapies for primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) is a rare type of extranodal lymphoma exclusively involving the CNS at the onset, with diffuse large B-cell lymphoma (DLBCL) as the most common histological subtype. As PCNSL is a malignancy arising in an immune-privileged site, suboptimal delivery of systemic agents into tumor tissues results in poorer outcomes in PCNSL than in non-CNS DLBCLs. Commonly used regimens for PCNSL include high-dose methotrexate-based chemotherapy with rituximab for induction therapy and intensive chemotherapy followed by autologous hematopoietic stem cell transplantation or whole-brain radiotherapy for consolidation therapy. Targeted agents against the B-cell receptor signaling pathway, microenvironment immunomodulation and blood-brain barrier (BBB) permeabilization appear to be promising in treating refractory/relapsed patients. Chimeric antigen receptor-T cells (CAR-T cells) have been shown to penetrate the BBB as a potential tool to manipulate this disease entity while controlling CAR-T cell-related encephalopathy syndrome. Future approaches may stratify patients according to age, performance status, molecular biomarkers and cellular bioinformation. This review summarizes the current therapies and emerging agents in clinical development for PCNSL treatment.

A single-center retrospective analysis of outcome measures and consolidation strategies for relapsed and refractory primary CNS lymphoma

BACKGROUND

Relapsed or refractory primary CNS lymphoma (rrPCNSL) is a rare and challenging malignancy for which better evidence is needed to guide management.

METHODS

We present a retrospective cohort of 66 consecutive patients with rrPCNSL treated at the University of Washington between 2000 and 2020. Immunosuppressed and secondary CNS lymphoma patients were excluded.

RESULTS

During a median follow-up of 40.5 months from initial diagnosis, median OS for relapsed disease was 14.1 (0.2-88.5) months and median PFS was 11.0 (0.2-73.9) months. At diagnosis (r² = 0.85, p < 0.001), first relapse (r² = 0.69, p < 0.001), multiple relapses (r² = 0.97, p < 0.001) PFS was highly correlated with OS. In contrast, there was no correlation between the duration of subsequent progression-free intervals. No difference in PFS or OS was seen between CSF or intraocular relapse and parenchymal relapse. Patients reinduced with high-dose methotrexate-based (HD-MTX) regimens had an overall response rate (ORR) of 86.7%. Consolidation with autologous stem cell transplant (ASCT) was associated with longer PFS compared to either no consolidation (p = 0.01) and trended to longer PFS when compared to other consolidation strategies (p = 0.06). OS was similarly improved in patients consolidated with ASCT compared with no consolidation (p = 0.04), but not compared with other consolidation (p = 0.22). Although patients receiving ASCT were younger, KPS, sex, and number of recurrences were similar between consolidation groups. A multivariate analysis confirmed an independent effect of consolidation group on PFS (p = 0.01), but not OS.

CONCLUSIONS

PFS may be a useful surrogate endpoint which predicts OS in PCNSL. Consolidation with ASCT was associated with improved PFS in rrPCNSL.

Challenging lymphoid malignancy of primary central nervous system lymphoma: A case report

Introduction

Primary central nervous lymphoma is an aggressive disease without evidence of systemic spread with an annual incidence of 7 cases per 1,000,000 people in the United States.

Case presentation

A 68-year-old gentleman of Malay ethnicity presented with left sided weakness associated with reduced sensation for one month. The patient was healthy and denied any constitutional symptoms, joint pains, rash or seizures. There was no recent trauma. Physical examination revealed left upper and lower limb motor grade power of 3/5 with upper motor neurone weakness of the left facial nerve. He had brisk reflexes and an upgoing extensor plantar response. Brain imaging (Magnetic Resonance Imaging) showed two lesions: one occupying the right head of the caudate nucleus and the other seen at the right side of the body of the corpus callosum. Histomorphology and immunohistochemistry confirmed Diffuse Large B-Cell Lymphoma (DLBCL) of non-germinal center type. He was treated with De Angelis protocol which involves chemoradiotherapy consisting of high dose methotrexate and whole brain radiotherapy (WBRT), followed by high dose cytarabine. Brain imaging post chemoradiation showed complete remission.

Conclusion

Prompt detection with appropriate therapeutic protocol could significantly minimise the permanent neurological deficits in patients with this rare and challenging lymphoid malignancy.

Effectiveness of digital PCR for MYD88L265P detection in vitreous fluid for primary central nervous system lymphoma diagnosis

Primary central nervous system lymphoma (PCNSL) is a rare type of primary extranodal lymphoma (PEL). MYD88^L265P mutation has been observed in up to 75% of PCNSL cases, however, the validity and sensitivity of digital PCR in detecting this mutation remains to be elucidated. A total of 44 PCNSL patients, 15 diffuse large B-cell lymphoma not otherwise specified (DLBCL-NOS) patients and 13 other PEL patients were enrolled in the present study. The abilities of reverse transcription quantitative PCR (RT-qPCR) and droplet digital PCR (ddPCR) to detect the MYD88^L265P mutation in cerebral spinal fluid (CSF) samples were compared. The results suggested that ddPCR showed superior mutation detection sensitivity when compared with RT-qPCR (58 vs. 15%; P<0.05). The MYD88^L265P mutation was significantly associated with increased MYD88 protein overexpression in PCNSL brain tissue samples (P<0.05). Analysis of MYD88^L265P mutation status in CSF and vitreous fluid samples using ddPCR may be a promising technique for minimally invasive confirmation of PCNSL diagnosis.

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.

Brain miliary enhancement

PURPOSE

Miliary enhancement refers to the presence of multiple small, monomorphic, enhancing foci on T1-weighted post-contrast MRI images. In the absence of a clear clinical presentation, a broad differential diagnosis may result in invasive procedures and possibly brain biopsy for diagnostic purposes.

METHODS

An extensive review of the literature is provided for diseases that may present with miliary enhancement on T1-weighted brain MR images. Additional disease-specific findings, both clinical and radiological, are summarized and categorized by the presence or absence of perivascular space involvement.

RESULTS

Miliary pattern of enhancement may be due to a variety of underlying causes, including inflammatory, infectious, nutritional or neoplastic processes. The recognition of disease spread along the perivascular spaces in addition to the detection or exclusion of disease-specific features on MRI images, such as leptomeningeal enhancement, presence of haemorrhagic lesions, spinal cord involvement and specific localisation or systemic involvement, allows to narrow the potential differential diagnoses.

CONCLUSION

A systematic approach to disease-specific findings from both clinical and radiological perspectives might facilitate diagnostic work-up, and recognition of disease spread along the perivascular spaces may help narrowing down differential diagnoses and may help to minimize the use of invasive diagnostic procedures.

Hematopoietic stem cell transplantation in primary central nervous system lymphoma: a review of the literature

Primary central nervous system lymphoma (PCNSL) is an uncommon variant of extranodal non-Hodgkin lymphoma (NHL) with an aggressive course and worse outcomes compared with other lymphomas of similar tumor burden and histologic subtype. High-dose chemotherapy supported by autologous stem cell transplantation (HDC/ASCT) is an option for therapy for this disease in both the relapse setting and as post-remission consolidation. Data are currently limited to only several single-arm phase II trials with small sample sizes, but randomized trials are now ongoing. In this review, we discuss the efficacy, feasibility, and toxicity of HDC/ASCT for PCNSL and its role in the treatment of this aggressive malignancy, both in the first-line and relapse settings. We also bring to attention the current data on allogeneic stem cell transplantation (allo-SCT) in PCNSL.

An Unusual Coexistence of Primary Central Nervous System Non-Hodgkin's Lymphoma and Acute Promyelocytic Leukemia

Acute promyelocytic leukemia and primary central nervous system lymphoma are uncommon hematological malignancies. The co-occurrence of acute myeloid leukemia with various lymphoproliferative diseases is an extremely rare condition, especially in the absence of previous chemotherapy or radiotherapy. Herein, we provide a comprehensive characterization of a patient with concomitant diagnosis of extranodal high-grade non-Hodgkin B-cell neoplasm confined to the central nervous system and acute promyelocytic leukemia. We describe the efficacy and feasibility of the consecutive use of all-trans retinoic acid and arsenic trioxide-containing regimen for the treatment of promyelocytic leukemia and high-dose methotrexate plus cytarabine to treat lymphoproliferative involvement of the central nervous system.

Staging identifies non-CNS malignancies in a large cohort with newly diagnosed lymphomatous brain lesions

Lymphomatous brain lesions can represent primary central nervous system (CNS) lymphoma or secondary involvement as part of systemic disease (SCNSL). In this study, we characterize staging evaluations in a large patient cohort with newly-diagnosed brain lymphomas, to determine the frequency of SCNSL and secondary malignancies. This retrospective review includes 262 patients with newly-diagnosed lymphomatous CNS lesions evaluated at Memorial Sloan Kettering Cancer Center between 2006 and 2018. Staging procedures included PET scans in 180 (69%) patients, CT scans of chest/abdomen/pelvis (CAP) in 195 (74%) and bone marrow biopsies (BMB) in 177 (68%). PET scans were reported as abnormal in 34 of 180 (19%), CT in 50 of 195 (26%) and BMB in 15 of 177 (8.5%). A total of 24 non-CNS malignancies were identified (11.8%; 19 systemic lymphomas and 5 secondary malignancies). Thus, in patients with new lymphomatous brain lesions, performing initial systemic staging procedures can identify systemic lymphoma and additional malignancies, highlighting the importance of staging evaluations, in particular PET and BMB.

Phase 1 study of pomalidomide and dexamethasone for relapsed/refractory primary CNS or vitreoretinal lymphoma

The combination of pomalidomide (POM) and dexamethasone (DEX) was evaluated for relapsed/refractory primary central nervous system lymphoma (PCNSL) and primary vitreoretinal lymphoma (PVRL) to determine the maximal tolerated dose (MTD) of POM as the primary objective, and overall response rate (ORR), progression-free survival (PFS), and safety profile as secondary objectives. A cohorts-of-3 study design was used with a dose-escalation schedule consisting of POM (3, 5, 7, or 10 mg) orally daily for 21 days every 28 days and DEX 40 mg orally every week. After 2 cycles, POM was continued alone until disease progression, intolerance, or subject withdrawal. Following MTD determination, the MTD cohort was expanded. Twenty-five of 29 patients with the median of 3 prior treatments were eligible for assessment as per international PCNSL collaborative group criteria. The MTD of POM was 5 mg daily for 21 days every 28 days. Whole-study ORR was 48% (12 of 25; 95% confidence interval [CI], 27.8%, 68.7%) with 6 complete response (CR), 2 complete response, unconfirmed (CRu), and 4 partial response (PR). MTD cohort ORR was 50% (8 of 16; 95% CI, 24.7%, 75.4%) with 5 CR, 1 CRu, and 2 PR. Median PFS was 5.3 months (whole study) and 9 months (for responders). One patient had pseudoprogression. Grade 3/4 hematologic toxicities included neutropenia (21%), anemia (8%), and thrombocytopenia (8%). Grade 3/4 nonhematologic toxicities included lung infection (12%), sepsis (4%), fatigue (8%), syncope (4%), dyspnea (4%), hypoxia (4%), respiratory failure (8%), and rash (4%). POM/DEX treatment is feasible with significant therapeutic activity against relapsed/refractory PCNSL and PVRL. This trial was registered at www.clinicaltrials.gov as #NCT01722305.

[Primary central nervous system methotrexate associated lymphoproliferative disorders in a patient with rheumatoid arthritis]

We report on a 52-year-old woman with rheumatoid arthritis (RA) who developed methotrexate associated lymphoproliferative disorders (MTX-LPD) in the central nervous system (CNS) in the course of immunosuppressive therapy for RA. The patient was admitted because of monoplegia in her left hand. She had been receiving methotrexate (MTX) for her RA for several years and etanercept had also been introduced because of a worsening of the arthritis six months before admission. Brain MRI revealed multiple lesions with enhancement scattered throughout both hemispheres. ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography showed abnormal accumulation suggesting malignancy in the right frontal lobe where abnormal enhancement was observed on the MRI. A brain biopsy was performed at the identified site and it confirmed diffuse large B-cell lymphoma (DLBCL). We therefore diagnosed her as MTX-LPD. According to previous reports, most MTX-LPD cases tend to show regression after the cessation of MTX. However, our case showed no regression and even needed chemotherapy. The patient had a poorer prognosis than previous cases and died 17 months after the onset. Although it is an uncommon complication, particularly in the CNS, MTX-LPD should be considered as a critical differential diagnosis if a patient receiving MTX develops central nervous system lesions. Immediate medical intervention including brain biopsy is required.

The Diagnosis and Treatment of Primary CNS Lymphoma

BACKGROUND

Primary central nervous system lymphoma is a diffuse large B-celllymphoma with exclusive manifestation in the central nervous system (CNS), leptomeninges, and eyes. Its incidence is 0.5 per 100 000 persons per year.Currently, no evidence-based standard of care exists.

METHODS

This review is based on pertinent publications (2000-2017) retrieved by aselective search in PubMed.

RESULTS

The clinical and neuroradiological presentation of primary CNS lymphoma isoften nonspecific, and histopathological confirmation is obligatory. The disease, if left un- treated, leads to death within weeks or months. If the patient's general condition permits, treatment should consist of a high-dose chemotherapy based on methotrexate (HD- MTX) combined with rituximab and other cytostatic drugs that penetrate the blood-brain barrier. Long-term survival can be achieved in patients under age 70 by adding non- myeloablative consolidation chemotherapy or high-dose chemotherapy with autologous stem cell transplantation (HD-AST) to the induction therapy. Clinical trials comparing the efficacy and toxicity of these two treatment strategies are currently underway. Con- solidation whole-brain radiotherapy is associated with the risk of severe neurotoxicity and should be reserved for patients who do not qualify for systemic treatment. Some 30% of patients are refractory to primary treatment, and at least 50% relapse. In patients who are still in good general condition, relapse can be managed with HD-AST. Re- exposure to conventional HD-MTX-based polychemotherapy is another option, if the initial response was durable. The 5-year survival rate of all treated patients is 31%,according to registry data.

CONCLUSION

Current recommendations for the treatment of primary CNS lymphomaare based on only a small number of prospective clinical trials. Patients with this disease should be treated by interdisciplinary teams in experienced centers, andpreferably as part of a controlled trial.

Combined alkylation and histone deacetylase inhibition with EDO-S101 has significant therapeutic activity against brain tumors in preclinical models

There is a clear unmet need for novel therapeutic agents for management of primary and secondary brain tumors. Novel therapeutic agents with excellent central nervous system (CNS) penetration and therapeutic activity are urgently needed. EDO-S101 is a novel alkylating and histone deacetylase inhibiting agent created by covalent fusion of bendamustine and vorinostat. We used murine models to perform CNS pharmacokinetic analysis and preclinical therapeutic evaluation of EDO-S101 for CNS lymphoma, metastatic triple-negative breast cancer of the brain, and glioblastoma multiforme. EDO-S101 has excellent CNS penetration of 13.8% and 16.5% by intravenous infusion and bolus administration respectively. It shows promising therapeutic activity against CNS lymphoma, metastatic triple-negative breast cancer of the brain, and glioblastoma multiforme with significant prolongation of survival compared to no-treatment controls. Therapeutic activity was higher with IV infusion compared to IV bolus. It should be evaluated further for therapeutic use in brain tumors.

Osteopontin is a multi-faceted pro-tumorigenic driver for central nervous system lymphoma

Osteopontin (OPN) is the most upregulated gene in primary central nervous system lymphoma (PCNSL) compared to non-CNS diffuse large B cell lymphoma (DLBCL). We show here that OPN is a key mediator of intracerebral tumor growth, invasion, and dissemination in CNS lymphoma, and that these effects depend upon activation of NF-κB. We further show that activation of NF-κB by OPN occurs through a unique mechanism in which intracellular OPN (iOPN) causes transcriptional downregulation of the NF-κB inhibitors, A20/TNFAIP3 and ABIN1/TNIP1, and secretory OPN (sOPN) promotes receptor-mediated activation of NF-κB. We also identify NF-κB-mediated induction of matrix metalloproteinase-8 (MMP-8) as a specific feature of OPN-mediated tissue invasion. These results implicate OPN as a candidate for development of targeted therapy for patients with PCNSL.

Primary diffuse large B-cell lymphoma of the CNS: a rare case of spontaneous remission

There is no consensus on the optimal therapy for primary CNS lymphoma. Conventional treatment modalities include chemotherapy and radiation therapy, which carry significant risks of morbidity and mortality. In systemic lymphomas, there are situations where non-Hodgkin lymphomas have resolved spontaneously. We now report the case of a nonimmunocompromised patient with primary CNS lymphoma who underwent a spontaneous remission with a durable response. This case suggests that not all patients with primary CNS lymphomas require aggressive treatment with chemotherapy and radiation therapy.

Natalizumab-Associated Primary Central Nervous System Lymphoma

OBJECTIVE

Natalizumab, a selective adhesion molecule inhibitor binding to an α-4 subunit of integrin, has emerged to be an effective immunomodulator, especially in the treatment of relapsing-remitting multiple sclerosis and Crohn disease. Recent reports documenting the development of primary central nervous system lymphoma (PCNSL) as a result of its administration have been concerning, and they trigger a debate about a possible causal association. In our report, we provide a comprehensive review of the literature on lymphoma development after natalizumab use, and we report an additional case of PCNSL development in a young woman who received natalizumab for her Crohn disease.

METHODS

A systematic (qualitative) review of literature on lymphoma development after natalizumab therapy was performed by use of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data on patient characteristics, indication for drug therapy, dosages, radiologic findings, potential risk factors for PCNSL, and tumor markers were synthesized. Additionally, we present the findings from the case of a young woman who received natalizumab therapy (4 doses, 300 mg each) for Crohn disease and in whom PCNSL developed.

RESULTS

Overall, 8 reports including our index case document lymphoma development after natalizumab use. Our case finding revisits the debate suggesting a remote possibility of association that warrants further evaluation and validation.

CONCLUSIONS

Evidence documenting a causal association of natalizumab and PCNSL is weak. Considering the potential benefits of using natalizumab for current indications, we recommend vigilant monitoring of patients receiving the drug for PCNSL outlook.

Hydrocephalus as the sole presentation of primary diffuse large B-cell lymphoma of the brain: Report of a case and review of literature

Background:

The most common lymphoid malignancy in adults is diffuse large B-cell lymphoma (DLBCL). The median age of occurrence of DLBCL is between 6^th and 7^th decade of life, although some other types of aggressive non-Hodgkin’s lymphomas (NHL) are present in younger age. Primary central nervous system lymphoma (PCNSL) is an uncommon type of extranodal NHL, which is either more prevalent or is diagnosed more often than before.

Case Description:

A 22-year-old man with ventriculoperitoneal shunt (VPS) performed at another center was referred with manifestations of shunt malfunction, unusual behavior, dysphasia, and hallucination. The shunt malfunction was handled appropriately several times and exploration of the enhancing cystic temporal lesion confirmed the diagnosis of DLBCL.

Conclusion:

In this communication, we intend to highlight the issue that hydrocephalus refractory to several interventions can be the sole manifestation of PCNSL and needs special clinical considerations.