Cognitive functions in primary CNS lymphoma after single or combined modality regimens

A Systematic Review of Cognitive Function, Anxiety, and Depression in Patients With Newly Diagnosed Primary Central Nervous System Lymphoma

OBJECTIVE

To retrospectively analyze the effects of different treatments on cognitive functioning, anxiety, and depression in patients with primary central nervous system lymphoma (PCNSL).

METHODS

A comprehensive literature search was conducted in multiple databases including the Cochrane Library, CINAHL, PubMed, Web of Science, EMBASE, Sino Med, Wei Pu, Wan Fang, CNKI, and Google Scholar. The search included studies published through June 20, 2023, focusing on cognitive function, anxiety, and depression in adult patients newly diagnosed with PCNSL. Various measurement tools and scales were used to assess the primary outcomes. Descriptive systematic reviews were conducted to integrate the literature and summarize the effects of different treatment modalities on cognitive functioning, anxiety, and depression in PCNSL patients. This review was registered with PROSPERO (CRD42022370250).

RESULTS

A total of 43 studies were included. Induction chemotherapy was associated with improved cognitive function and reduced anxiety and depression in the majority of patients. Whole-brain radiotherapy (WBRT) was found to lead to cognitive impairment, particularly in executive, attention, memory, and motor function. Low-dose WBRT, autologous stem cell transplantation (ASCT), and blood-brain barrier disruption (BBBD) treatments did not result in significant cognitive impairment. Anxiety and depression were observed to decrease over the long term.

CONCLUSIONS

Overall, the cognitive functioning, anxiety, and depression of patients with PCNSL can be improved with appropriate treatments. However, patients treated with WBRT are at a higher risk of cognitive decline compared to those receiving other treatment modalities. Therefore, special attention should be given to patients undergoing WBRT, and a comprehensive analysis should be conducted to reduce neurotoxicity and address early cognitive problems in these patients.

A phase 2 study of ibrutinib maintenance following first-line high-dose methotrexate-based chemotherapy for elderly patients with primary central nervous system lymphoma

BACKGROUND

Elderly patients account for nearly 70% of all primary central nervous system lymphoma (PCNSL) cases. They cannot tolerate aggressive treatment and have poor prognosis with a median overall survival (OS) of less than 2 years and progression-free survival (PFS) of 6-16 months. Ibrutinib penetrates the blood-brain barrier and has shown activity in PCNSL.

METHODS

This prospective study investigated whether ibrutinib maintenance is feasible, and whether it can benefit elderly PCNSL patients in terms of expected 2-year PFS. It is an open label, phase 2 study in newly diagnosed PCNSL patients 60-85 years old who responded to first-line high-dose methotrexate (HDMTX)-based treatment with partial or complete response. Ibrutinib maintenance (560 mg/d) was continued until disease progression or intolerable toxicity.

RESULTS

Twenty patients were enrolled, with a median age of 72 years (range, 61-80). Median time on ibrutinib maintenance was 12.5 (range, 2-46) months. Twelve patients stopped treatment: five due to central nervous system relapse and seven due to adverse events that were mainly grade 2. Five patients died (25%) all due to relapse. The 1- and 2-year PFS are 90% and 72.6%, respectively, and the 2-year OS is 89%.

CONCLUSIONS

The study reached its primary end points and also showed that ibrutinib maintenance is tolerated reasonably well by the elderly. Therefore, this study supports the concept that ibrutinib maintenance should be further evaluated as an optional consolidation measure in the elderly.

Evidence-based management of primary and secondary CNS lymphoma

Central nervous system (CNS) lymphoma has traditionally had very poor outcomes however advances in management have resulted in dramatic improvements and long-term survival of patients. We describe the evidence for treatment strategies for these aggressive disorders. In primary CNS lymphoma there are randomized trial data to inform treatment decisions but these are lacking to guide management in secondary CNS lymphoma. Dynamic assessment of patient fitness and frailty is key throughout treatment, alongside delivery of CNS-bioavailable therapy and enrolment in clinical trials, at each stage of the disease. Intensive high-dose methotrexate-containing induction followed by consolidation with autologous stem cell transplantation with thiotepa-based conditioning is recommended for patients who are fit. Less intensive chemoimmunotherapy, novel agents (including Bruton tyrosine kinase inhibitors, cereblon targeting immunomodulatory agents, and checkpoint inhibitors in the context of clinical trials), and whole brain radiotherapy may be reserved for less fit patients or disease which is chemoresistant. Data regarding the efficacy of chimeric antigen receptor T-cells therapy is emerging, and concerns regarding greater toxicity have not been realized. Future areas of prospective studies include the identification of those at high risk of developing CNS lymphoma, management in elderly or frail patients as well as incorporating novel agents into regimens, particularly for those with chemoresistant disease.

Long-term survival after salvage pemetrexed for refractory primary T-cell lymphoma of the CNS

Primary T-cell CNS lymphoma is a rare and aggressive malignancy. High-dose methotrexate (MTX) based chemotherapy regimens are used as standard first-line treatment, followed by consolidative strategies to improve the duration of response. Although MTX-based therapy has been shown to be efficacious, treatment options for MTX-refractory disease are not well-defined. Here, we report a case of a 38-year-old man with refractory primary T-cell CNS lymphoma who demonstrated a complete response to pemetrexed treatment. He subsequently received conditioning chemotherapy consisting of thiotepa, busulfan and cyclophosphamide followed by autologous stem cell transplantation. The patient continues to remain recurrence-free to date at 9 years post-treatment.

The mechanism of impaired delayed recall verbal memory function in Parkinson's disease with orthostatic hypotension: a multiple imaging study

Introduction

Orthostatic hypotension (OH) frequently accompanies autonomic dysfunction and is an important risk factor for cognitive impairment in Parkinson's disease (PD). However, the association between different cognitive functions and OH in PD patients is not yet fully understood.

Methods

This study aimed to evaluate the scores of different cognitive domains and multiple parameters using different imaging techniques on PD patients with or without OH. A total number of 31 PD patients with OH (n = 20) and without OH (n = 11) were recruited from the Department of Neurology, Beijing Xuanwu Hospital for this study. All patients underwent beat-to-beat non-invasive blood pressure recordings and an active standing test to evaluate neurogenic OH and a global neuropsychological test to assess cognitive function. All patients underwent dynamic cerebral autoregulation (dCA) measurement, brain magnetic resonance imaging (MRI), and brain 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT).

Results

The results showed that OH patients had poor delayed recall verbal memory when compared with the PD patients without OH (1.75 ± 1.59 vs. 3.10 ± 1.73, p = 0.042). The dCA test indicated a significant difference in the right very low-frequency (VLF) gain between two groups (1.27 ± 0.17 vs. 1.10 ± 0.26, p = 0.045) and the brain 18F-FDG PET/CT indicated a significant difference in the SUV (right medial temporal lobe) to SUV (occipital lobe) ratio (0.60 ± 0.08 vs. 0.67 ± 0.11, p = 0.049). Meanwhile, these two imaging parameters were negatively correlated (p < 0.001). Furthermore, the score of a delayed recall verbal memory in the OH group was positively correlated with the right medial temporal lobe to occipital lobe ratio (p < 0.001) and was negatively correlated with the right VLF gain (p = 0.023).

Discussion

PD with OH patients had poor delayed recall memory, which might have been caused by the decreased metabolic dysfunction of specific medial temporal lobe due to the impaired dCA ability.

Management of primary and secondary CNS lymphoma

Central nervous system (CNS) lymphoma has traditionally had very poor outcomes however advances in management have seen dramatic improvements and long-term survival of patients. In primary CNS lymphoma there are now randomised trial data to inform practice, however secondary CNS lymphoma has a lack of randomised trial data and CNS prophylaxis remains a contentious area. We describe treatment strategies in these aggressive disorders. Dynamic assessment of patient fitness and frailty is key throughout treatment alongside delivery of CNS-bioavailable therapy and enrolment in clinical trials. Intensive high-dose methotrexate-containing induction followed by autologous stem cell transplantation is preferred for patients who are fit. Less intensive chemoimmunotherapy, whole brain radiotherapy and novel therapies may be reserved for patients unfit or chemoresistant. It is essential to better define patients at increased risk of CNS relapse, as well as effective prophylactic strategies to prevent it. Future prospective studies incorporating novel agents are key.

Primary central nervous system lymphoma: a practical guide for neurologists

Primary central nervous system lymphoma is rare, comprising 4% of intracranial neoplasms. Although haematologists or oncologists subsequently manage the condition, it is often neurologists who first make, or at least suspect, the diagnosis. This article reviews the disease, its clinical and radiological features and details the work-up needed to achieve a diagnosis (namely histological or cytological confirmation) and to prepare the patient for treatment. We note the importance of brain biopsy, the role of corticosteroids and the varied treatment options.

Blood-Brain Barrier Disruption (BBBD)-Based Immunochemotherapy for Primary Central Nervous System Lymphoma (PCNSL), Early Results of a Phase II Study

Primary central nervous system lymphoma is a rare but aggressive brain malignancy. It is associated with poor prognosis even with the current standard of care. The aim of this study was to evaluate the effect and tolerability of blood-brain barrier disruption treatment combined with high-dose treatment with autologous stem cell transplantation as consolidation on primary central nervous system lymphoma patients. We performed a prospective phase II study for 25 patients with previously untreated primary central nervous system lymphoma. The blood-brain barrier disruption treatment was initiated 3-4 weeks after the MATRix regimen using the previously optimized therapy protocol. Briefly, each chemotherapy cycle included two subsequent intra-arterial blood-brain barrier disruption treatments on days 1 and 2 via either one of the internal carotid arteries or vertebral arteries. Patients received the therapy in 3-week intervals. The treatment was continued for two more courses after achieving a maximal radiological response to the maximum of six courses. The complete treatment response was observed in 88.0% of the patients. At the median follow-up time of 30 months, median progression-free and overall survivals were not reached. The 2-year overall and progression-free survival rates were 67.1% and 70.3%, respectively. Blood-brain barrier disruption treatment is a promising option for primary central nervous system lymphoma with an acceptable toxicity profile.

Neurocognitive and radiological changes after cranial radiation therapy in humans and rodents: a systematic review

BACKGROUND

Radiation-induced brain injury is a common long-term side effect for brain cancer survivors, leading to a reduced quality of life. Although there is growing research pertaining to this topic, the relationship between cognitive and radiologically detected lesions of radiation-induced brain injury in humans remains unclear. Furthermore, clinically translatable similarities between rodent models and human findings are also undefined. The objective of this review is to then identify the current evidence of radiation-induced brain injury in humans and to compare these findings to current rodent models of radiation-induced brain injury.

METHODS

This review includes an examination of the current literature on cognitive and radiological characteristics of radiation-induced brain injury in humans and rodents. A thorough search was conducted on PubMed, Web of Science, and Scopus to identify studies that performed cognitive assessments and magnetic resonance imaging techniques on either humans or rodents after cranial radiation therapy. A qualitative synthesis of the data is herein reported.

RESULTS

A total of 153 studies pertaining to cognitively or radiologically detected radiation injury of the brain are included in this systematic review; 106 studies provided data on humans while 47 studies provided data on rodents. Cognitive deficits in humans manifest across multiple domains after brain irradiation. Radiological evidence in humans highlight various neuroimaging-detectable changes post-irradiation. It is unclear, however, whether these findings reflect ground truth or research interests. Additionally, rodent models do not comprehensively reproduce characteristics of cognitive and radiological injury currently identified in humans.

CONCLUSION

This systematic review demonstrates that associations between and within cognitive and radiological radiation-induced brain injuries often rely on the type of assessment. Well-designed studies that evaluate the spectrum of potential injury are required for a precise understanding of not only the clinical significance of radiation-induced brain injury in humans, but also how to replicate injury development in pre-clinical models.

Diagnosis and Treatment Using Autologous Stem-Cell Transplantation in Primary Central Nervous System Lymphoma: A Systematic Review

BACKGROUND

Consolidation therapy has improved the outcome of newly diagnosed PCNSL patients. Whole-brain radiotherapy (WBRT) was the first consolidation strategy used and represented the gold standard for many years, but at the expense of a high risk of neurotoxicity. Thus, alternative strategies are being investigated in order to improve disease outcomes and to spare the neurocognitive side effects due to WBRT.

METHODS

We reviewed published studies on PCNSL patients treated with HDC/ASCT, focusing on the efficacy and safety of the conditioning regimens. Prospective and retrospective studies, published in the English language from 1992 to 2022, in high-quality international journals were identified in PubMed.

RESULTS

Consolidation with HDC containing highly CNS-penetrating agents (thiotepa, busulfan or BCNU) followed by ASCT provided long-term disease control and survival in PCNSL patients. Two prospective randomized studies, comparing HDC/ASCT versus WBRT, reported similar progression-free survival (PFS) and similar results on the decline in neurocognitive functions in a substantial proportion of patients after WBRT but not after HDC-ASCT. A recent randomized study comparing HDC/ASCT versus non-myeloablative consolidation reported a longer PFS in transplanted patients.

CONCLUSION

ASCT conditioned with regimens, including highly CNS-penetrating agents, represents, to date, the best choice among the available consolidation strategies for fit newly diagnosed PCNSL patients.

European Association of Neuro-Oncology (EANO) guidelines for treatment of primary central nervous system lymphoma (PCNSL)

The management of primary central nervous system (PCNSL) is one of the most controversial topics in neuro-oncology because of the complexity of the disease and the limited number of controlled studies available. In 2021, given recent advances and the publication of practice-changing randomized trials, the European Association of Neuro-Oncology (EANO) created a multidisciplinary task force to update the previously published evidence-based guidelines for immunocompetent adult patients with PCNSL and added a section on immunosuppressed patients. The guideline provides consensus considerations and recommendations for the treatment of PCNSL, including intraocular manifestations and specific management of the elderly. The main changes from the previous guideline include strengthened evidence for the consolidation with ASCT in first-line treatment, prospectively assessed chemotherapy combinations for both young and elderly patients, clarification of the role of rituximab even though the data remain inconclusive, of the role of new agents, and the incorporation of immunosuppressed patients and primary ocular lymphoma. The guideline should aid the clinicians in everyday practice and decision making and serve as a basis for future research in the field.

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.

Treatment Options for Recurrent Primary CNS Lymphoma

OPINION STATEMENT

Primary CNS lymphoma (PCNSL) constitutes a rare extranodal variant of non-Hodgkin lymphoma (NHL) with an annual incidence of 0.45/100,000. Given the paucity of large prospective clinical trials, there is no consensus treatment for refractory or relapsed (r/r) PCNSL, and available strategies are largely based on retrospective analyses. Patient age, performance status, previously administered treatment, duration of response, and molecular characteristics guide selection of salvage therapy. Patients with a good performance status (KPS >70), particularly ≤65 years, and adequate organ function should be considered for salvage polychemotherapy. Based on its high overall response rate even in the relapsed setting, we choose high-dose (≥ 3.5g/m²) methotrexate (HD-MTX) based regimens, e.g., R-MPV (rituximab, HD-MTX, procarbazine, and vincristine), for remission re-induction as long as patients were sensitive to first line HD-MTX-based regimens, especially when duration of previous response was ≥ 1 year. Following successful remission induction, we choose myeloablative chemotherapy (e.g., thiotepa, busulfan, cyclophosphamide) and subsequent autologous stem cell transplant in curative intent whenever feasible. Alternatively, conventional chemotherapy regimens (for example, monthly HD-MTX) or low-dose whole-brain radiation therapy (WBRT) are selected for consolidation in non-transplant candidates in complete remission. In cases of HD-MTX refractory disease or contraindications, we use pemetrexed; temozolomide/rituximab; high-dose cytarabine; or whole brain radiation for remission induction. Clinical trial participation is considered as well. Emerging therapies for upfront or salvage therapy under ongoing investigation include bruton tyrosine kinase inhibition (e.g., ibrutinib), immunomodulatory drugs (e.g., lenalidomide), immune checkpoint inhibitors (ICI, e.g., nivolumab), and chimeric antigen receptor T (CAR-T) cell therapy.

Long-term efficacy, safety and neurotolerability of MATRix regimen followed by autologous transplant in primary CNS lymphoma: 7-year results of the IELSG32 randomized trial

219 HIV-negative adults ≤70 years with primary CNS lymphoma (PCNSL) were enrolled in the randomized IELSG32 trial. Enrolled patients were randomly assigned to receive methotrexate-cytarabine (arm A), or methotrexate-cytarabine-rituximab (B), or methotrexate-cytarabine-thiotepa-rituximab (MATRix; arm C). A second randomization allocated patients with responsive/stable disease to whole-brain irradiation (WBRT) or carmustine-thiotepa-conditioned autologous transplantation (ASCT). First results, after a median follow-up of 30 months, showed that MATRix significantly improves outcome, with both WBRT and ASCT being similarly effective. However, sound assessment of overall survival (OS), efficacy of salvage therapy, late complications, secondary tumors, and cognitive impairment requires longer follow-up. Herein, we report the results of this trial at a median follow-up of 88 months. As main findings, MATRix was associated with excellent long-lasting outcome, with a 7-year OS of 21%, 37%, and 56% respectively for arms A, B, and C. Notably, patients treated with MATRix and consolidation had a 7-year OS of 70%. The superiority of arm B on arm A suggests a benefit from the addition of rituximab. Comparable efficacy of WBRT and ASCT was confirmed. Salvage therapy was ineffective; benefit was recorded only in patients with late relapse re-treated with methotrexate. Eight (4%) patients developed a second cancer. Importantly, MATRix and ASCT did not result in higher non-relapse mortality or second tumors incidence. Patients who received WBRT experienced impairment in attentiveness and executive functions, whereas patients undergoing ASCT experienced improvement in these functions as well as in memory and quality of life.

CNS Lymphoma: Clinical Pearls and Management Considerations

Primary CNS lymphoma presents unique challenges for the clinician. New evidence has emerged regarding the appropriate workup, management considerations, and treatment. In this paper, we highlight the clinical presentations, disease prognosis, and management considerations. We place specific emphasis on the decision tree for immunocompetent and immunocompromised. The key imaging characteristics are discussed. Once biopsy prove lymphoma, important management considerations are addressed. We highlight need for follow up and role for surgery verse radiation. Finally, we present emerging treatment options and pre-clinical work that will be making its way through the pipeline. This up-to-date review will serve as a key learning tool for clinicians and researchers.

Efficacy and Safety of Autologous Stem-Cell Transplantation as Part of First-Line Treatment for Newly Diagnosed Primary Central Nervous System Lymphoma: A Systematic Review and Meta-Analysis

Objective

The reviewed literature supports a treatment regimen for primary central nervous system lymphoma (PCNSL) that includes induction chemotherapy, followed by one consolidation therapy. High-dose chemotherapy supported by autologous stem-cell transplantation (ASCT) is the most studied option, but its effects are controversial. The aim of this study was to evaluate the efficacy and safety of ASCT for newly diagnosed PCNSL by means of a meta-analysis.

Methods

The PubMed, Embase, and Cochrane Library databases were systematically searched for studies published until May 20, 2021. Included studies were prospective studies of patients with newly diagnosed PCNSL treated with ASCT. The pooled rates and 95% confidence intervals (CIs) were determined for all outcomes. Subgroup analysis was conducted to compare the relative risk (RR) with 95% CIs for the complete remission (CR) rate and the hazard ratios (HRs) with 95% CIs for progression-free survival (PFS) and overall survival (OS).

Results

Thirteen prospective studies including 348 patients were analyzed. The pooled CR rate, overall response rate, and relapse rate were 80% (95% CI, 71–88%, I² = 67.06%, p = 0.00), 95% (95% CI, 87–100%, I² = 73.65%, p= 0.00), and 19% (95% CI, 15–24%, I² = 76.18%, p = 0.00), respectively. The pooled 2- and 5-year PFS and OS rates were 74% (95% CI, 68–80%, I² = 3.90%), 65% (95% CI, 51–77%, I² = 74.61%), 80% (95% CI, 72–88%, I² = 57.54%), and 69% (95% CI, 53–83%, I² = 83.89%), respectively. Hematological toxicity and infections were more common adverse events above grade 3. The pooled treatment-related mortality was 3% (95% CI, 1–6%, I² = 28.18%, p = 0.16). In the group analysis of ASCT compared with whole-brain radiotherapy, there were no significant differences in the CR rate (RR, 1.00, 95% CI, 0.88–1.14, p = 0.971), relapse rate (RR, 0.44, 95% CI, 0.06–3.10, p = 0.408), PFS (HR, 1.28, 95% CI, 0.81–2.01, p = 0.29), or OS (HR, 1.62, 95% CI, 0.97–2.69, p = 0.06). Cognitive functions were preserved or improved after ASCT.

Conclusions

ASCT is a feasible approach for consolidation with good tolerability for newly diagnosed PCNSL patients. High-quality randomized controlled trials are still needed to confirm the effects of ASCT.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021268422.

A narrative review of consolidation strategies for young and fit patients with newly-diagnosed primary central nervous system lymphoma

INTRODUCTION

The modern treatment of patients with primary central nervous system lymphoma (PCNSL) consists of two phases: induction, currently represented by a high-dose-methotrexate-based polychemotherapy, and consolidation. The optimal consolidation therapy has not been defined yet, but several strategies, such as whole-brain radiotherapy (WBRT), high-dose chemotherapy supported by autologous stem cell transplantation (HDC/ASCT) or non-myeloablative chemotherapy, have been addressed in important randomized trials.

AREAS COVERED

This review provides an overview of the current role of consolidation strategies in young and fit patients with newly-diagnosed PCNSL. Publications in English language, peer-reviewed, from high-quality international journals, edited from 2003 to 2021 were identified on PubMed.

EXPERT OPINION

Consolidation treatment significantly improved outcomes of PCNSL. Radiotherapy had represented for years the only choice in the consolidation therapy, but large randomized trials have demonstrated that HDC/ASCT is equally effective and associated with lower neurotoxicity risk in patients younger than 65-70 years. Encouraging results have been obtained using reduced-dose WBRT, while a recent randomized trial failed to demonstrate that consolidation with non-myeloablative chemotherapy is more effective than HDC/ASCT in PCNSL patients. A personalized consolidation treatment, driven also by a response prediction model based on radiological and molecular details, may improve the management of PCNSL patients.

Efficacy of Boron Neutron Capture Therapy in Primary Central Nervous System Lymphoma: In Vitro and In Vivo Evaluation

Background: Boron neutron capture therapy (BNCT) is a nuclear reaction-based tumor cell-selective particle irradiation method. High-dose methotrexate and whole-brain radiation therapy (WBRT) are the recommended treatments for primary central nervous system lymphoma (PCNSL). This tumor responds well to initial treatment but relapses even after successful treatment, and the prognosis is poor as there is no safe and effective treatment for relapse. In this study, we aimed to conduct basic research to explore the possibility of using BNCT as a treatment for PCNSL. Methods: The boron concentration in human lymphoma cells was measured. Subsequently, neutron irradiation experiments on lymphoma cells were conducted. A mouse central nervous system (CNS) lymphoma model was created to evaluate the biodistribution of boron after the administration of borono-phenylalanine as a capture agent. In the neutron irradiation study of a mouse PCNSL model, the therapeutic effect of BNCT on PCNSL was evaluated in terms of survival. Results: The boron uptake capability of human lymphoma cells was sufficiently high both in vitro and in vivo. In the neutron irradiation study, the BNCT group showed a higher cell killing effect and prolonged survival compared with the control group. Conclusions: A new therapeutic approach for PCNSL is urgently required, and BNCT may be a promising treatment for PCNSL. The results of this study, including those of neutron irradiation, suggest success in the conduct of future clinical trials to explore the possibility of BNCT as a new treatment option for PCNSL.

Preservation of neurocognitive function in the treatment of brain metastases

Neurocognitive function (NCF) deficits are common in patients with brain metastases, occurring in up to 90% of cases. NCF deficits may be caused by tumor-related factors and/or treatment for the metastasis, including surgery, radiation therapy, chemotherapy, and immunotherapy. In recent years, strategies to prevent negative impact of treatments and ameliorate cognitive deficits for patients with brain tumors have gained momentum. In this review, we report on research that has established the efficacy of preventative and rehabilitative therapies for NCF deficits in patients with brain metastases. Surgical strategies include the use of laser interstitial thermal therapy and intraoperative mapping. Radiotherapy approaches include focal treatments such as stereotactic radiosurgery and tailored approaches such as hippocampal avoidant whole-brain radiotherapy (WBRT). Pharmacologic options include use of the neuroprotectant memantine to reduce cognitive decline induced by WBRT and incorporation of medications traditionally used for attention and memory problems. Integration of neuropsychology into the care of patients with brain metastases helps characterize cognitive patterns, educate patients and families regarding their management, and guide rehabilitative therapies. These and other strategies will become even more important for long-term survivors of brain metastases as treatment options improve.

Treatment of Primary CNS Lymphoma: Maximizing Clinical Benefit, Minimizing Neurotoxicity

PURPOSE OF REVIEW

The optimal treatment for newly diagnosed and refractory or relapsed primary central nervous system lymphoma (PCNSL) is not fully defined. We review the epidemiology, clinical presentation, and current management strategies for newly diagnosed PCNSL as well as emerging treatments for refractory and relapsed disease.

RECENT FINDINGS

In recent decades, the incidence of PCNSL has increased in the elderly population. With advancements in chemotherapy for PCNSL, survival has improved. However, outcomes remain inferior when compared with other forms of extranodal lymphoma. Additionally, treatments can be associated with clinically significant neurotoxicities. Despite advances in the treatment of PCNSL, current treatment regimens remain suboptimal in terms of response rates and neurotoxicity. Well-tolerated agents, especially for the elderly, are still needed.

Neurologic complications in patients with lymphoid cancer

Neurologic complications of lymphoid cancer can be challenging to recognize and treat. The nervous system can be affected directly by hematogenous or local spread of lymphoma. Indirect neurologic effects of lymphoma include paraneoplastic syndromes and vascular complications. Lymphoma treatments can also cause neurologic complications. Early identification and treatment are crucial to stabilize or reverse neurologic deficits, prevent further nervous system injury, and to optimize overall oncologic therapy. This article provides an overview of different neurologic complications of lymphoma and its treatments, in addition to presentation of case studies that emphasize commonly encountered clinical scenarios.

Radiation therapy-associated toxicity: Etiology, management, and prevention

Radiation therapy (RT) is a curative treatment for many malignancies and provides effective palliation in patients with tumor-related symptoms. However, the biophysical effects of RT are not specific to tumor cells and may produce toxicity due to exposure of surrounding organs and tissues. In this article, the authors review the clinical context, pathophysiology, risk factors, presentation, and management of RT side effects in each human organ system. Ionizing radiation works by producing DNA damage leading to tumor death, but effects on normal tissue may result in acute and/or late toxicity. The manifestation of toxicity depends on both cellular characteristics and affected organs' anatomy and physiology. There is usually a direct relationship between the radiation dose and volume to normal tissues and the risk of toxicity, which has led to guidelines and recommended dose limits for most tissues. Side effects are multifactorial, with contributions from baseline patient characteristics and other oncologic treatments. Technological advances in recent decades have decreased RT toxicity by dramatically improving the ability to deliver RT that maximizes tumor dose and minimizes organ dose. Thus the study of RT-associated toxicity is a complex, core component of radiation oncology training that continues to evolve alongside advances in cancer management. Because RT is used in up to one-half of all patients with cancer, an understanding of its acute and late effects in different organ systems is clinically pertinent to both oncologists and nononcologists.

Role of 23.4 Gy upfront whole-brain radiation therapy following high-dose methotrexate for primary central nervous system lymphoma: a comparative analysis of whole-brain radiation therapy versus no radiation therapy

INTRODUCTION

We aimed to investigate the role of upfront whole-brain radiation therapy (RT), with a reduced dose of 23.4 Gy, following high-dose methotrexate (HD-MTX) in patients with primary central nervous system lymphoma (PCNSL).

METHODS

We retrospectively reviewed 185 patients with PCNSL treated with HD-MTX between January 2013 and January 2020; 145 patients underwent no RT and 40 patients underwent upfront RT. Using propensity score matching (PSM) to adjust for clinical factors, 40 patients were selected from each treatment group. Event-free survival (EFS) and overall survival (OS) were compared between treatment groups.

RESULTS

At baseline, patients in the upfront RT group were younger, had higher LDH levels, received less frequent rituximab and stem cell transplantation than those in the no-RT group. Patients in the upfront RT group also showed a lower response rate after initial HD-MTX than those in the no-RT group (73% vs. 88%, p = 0.038). The median follow-up was 25.1 (interquartile range 13.7-43.0) months. Comparable 2-year EFS and OS rates were observed between the upfront RT and no-RT groups (56.6% vs. 53.8%, p = 0.170; and 81.7% vs. 75.3%, p = 0.097, respectively). Upfront RT was related to improved EFS and OS in patients with stable disease or progressive disease after HD-MTX, but not in patients with complete or partial response after HD-MTX. Upfront RT was also an independent predictor of EFS and OS in the PSM cohort. The cumulative incidences of treatment-related neurotoxicity at 3 years were 20.2% and 21.2% in the upfront RT and no-RT groups, respectively (p = 0.630).

CONCLUSIONS

Upfront RT with a reduced dose of 23.4 Gy, showed favorable outcomes in patients with stable disease or progressive disease after initial HD-MTX. In addition, upfront RT appears to be an effective treatment for PCNSL when rituximab or stem cell transplantation is not feasible.

Is There an Indication for First Line Radiotherapy in Primary CNS Lymphoma?

Background: Primary CNS Lymphoma is a rare and severe but potentially curable disease. In the last thirty years treatment has changed significantly. Survival times increased due to high-dose methotrexate-based chemotherapy. With intensive regimens involving autologous stem cell transplantation (ASCT), 4-year survival rates of more than 80% can be reached. However, this treatment regimen is not feasible in all patients, and is associated with some mortality. Methods: In this review, current evidence regarding the efficacy and toxicity of radiotherapy in PCNSL shall be summarized and discussed mainly based on data of controlled trials. Results: Being the first feasible treatment whole brain radiotherapy (WBRT) was initially used alone, and later as a consolidating treatment after high-dose methotrexate-based chemotherapy. More recently, concerns regarding activity and neurotoxicity of standard dose WBRT limited its use. On the contrary, latest evidence of some phase II trials suggests efficacy of consolidating WBRT is comparable to ASCT. After complete remission reduced dose WBRT appears as a feasible concept with decreased neurotoxicity. Evidence for use of local stereotactic radiotherapy is very limited. Conclusion: Radiotherapy has a role in the treatment of PCNSL patients not suitable to ASCT, e.g., as consolidating reduced dose WBRT after complete response. Local stereotactic radiotherapy for residual disease should be examined in future trials.

Tumor Metabolism and Neurocognition in CNS Lymphoma

BACKGROUND

The mechanistic basis for neurocognitive deficits in CNS lymphoma and other brain tumors is incompletely understood. We tested the hypothesis that tumor metabolism impairs neurotransmitter pathways and neurocognitive function.

METHODS

We performed serial cerebrospinal fluid (CSF) metabolomic analyses using liquid chromatography-electrospray tandem mass spectrometry to evaluate changes in the tumor microenvironment in 14 patients with recurrent CNS lymphoma, focusing on 18 metabolites involved in neurotransmission and bioenergetics. These were paired with serial mini-mental state examinations (MMSE) and MRI studies for tumor volumetric analyses. Patients were analyzed in the setting of the phase I trial of lenalidomide/rituximab. Associations were assessed by Pearson and Spearman correlation coefficient. Generalized estimating equation (gee) models were also established, adjusting for within-subject repeated measures.

RESULTS

Of 18 metabolites, elevated CSF lactate correlated most strongly with lower MMSE score (p<8E-8, rho=-0.67). High lactate was associated with lower GABA, higher glutamate/GABA ratio and dopamine. Conversely, high succinate correlated with higher MMSE score. Serial analysis demonstrated a reproducible, time-dependent, reciprocal correlation between changes in lactate and GABA concentrations. While high lactate and low GABA correlated with tumor contrast enhancing volume, they correlated more significantly with lower MMSE scores than tumor volumes.

CONCLUSIONS

We provide evidence that lactate production and Warburg metabolism may impact neurotransmitter dysregulation and neurocognition in CNS lymphomas. We identify novel metabolomic biomarkers that may be applied in future studies of neurocognition in CNS lymphomas. Elucidation of mechanistic interactions between lymphoma metabolism, neurotransmitter imbalance and neurocognition may promote interventions that preserve cognitive function.

The Role of Radiation Therapy in the Older Patient

PURPOSE OF REVIEW

Older patients represent a unique subgroup of the cancer patient population for which the role of radiation therapy (RT) requires special consideration. This review will discuss many of these considerations as well as various radiation treatment techniques in the context of a variety of disease sites.

RECENT FINDINGS

Several recent studies give insight into the management of older cancer patients considering their age, performance status, comorbid conditions, quality of life, genetics, cost, and individual goals. RT plays an evolving and pivotal role in providing optimal care for this population. Recent advances in RT technique allow for more precise treatment delivery and reduced toxicity. Studies evaluating the use of radiation therapy in breast, brain, lung, prostate, rectal, pancreatic, esophageal, and oligometastatic cancer are summarized and discussed in the context of treating the older patient population. Individual age, performance and functional status, comorbid conditions, and patients' objectives and goals should all be considered when presenting treatment options for older patients and age alone should not disqualify patients from curative intent treatments. When possible, hypofractionated courses should be utilized as outcomes are often equivalent and toxicities are reduced. In many cases, RT may be preferable to other treatment options due to decreased toxicity profile and acceptable disease control.

Neurotoxicity of Cancer Therapies

PURPOSE OF REVIEW

This article reviews neurologic complications associated with chemotherapy, radiation therapy, antiangiogenic therapy, and immunotherapy.

RECENT FINDINGS

Cancer therapies can cause a wide range of neurologic adverse effects and may result in significant patient morbidity and mortality. Although some treatment-associated neurologic complications manifest acutely and are often reversible and transient, others occur with delayed onset, can be progressive, and are uniquely challenging to patient management. With an increase in multimodality and combination therapies, including targeted therapies and immunotherapies, and prolonged patient survival, novel and unique patterns of neurologic complications have emerged.

SUMMARY

Both conventional and novel cancer therapies can adversely affect the nervous system, thereby producing a wide range of neurologic complications. Increased awareness among neurologists and early recognition of cancer therapy-induced neurotoxic syndromes is critically important to minimize patient morbidity, prevent permanent injury, and improve patient outcomes.

Consolidation Treatment for Primary Central Nervous System Lymphoma: Which Modality for Whom?

Primary central nervous system lymphoma is a rare aggressive disease that largely affects elderly patients and is associated with poor prognosis. The optimal treatment approach is not yet defined and it consists of induction and consolidation phases. The combination of high-dose (HD) methotrexate-based chemotherapy followed by whole-brain radiotherapy (WBRT) prolongs the median progression-free survival (PFS) and overall survival 2- to 3-fold as compared to WBRT alone but is associated with significant delayed neurotoxicity. Alternative strategies are being investigated in order to improve disease outcomes and spare patients the neurocognitive side effects. These include reduced-dose WBRT, non-myeloablative HD chemotherapy, or HD chemotherapy with autologous stem cell transplantation (HDC/ASCT). There are no randomized studies that compare all these consolidation regimens head to head but recently HDC/ASCT has been evaluated versus WBRT in prospective randomized studies. These studies proved that WBRT and HDC/ASCT yield similar 2-year PFS with preserved or improved cognitive function after HDC/ASCT. Yet, the proportion of patients treated with such intensive consolidation is low, both in real life and in specialized centers, leaving many unsettled issues. This review is appraising current dilemmas related to the choice of consolidating therapeutic modalities, their associated acute and delayed toxicity, and future prospects for alternative approaches in the elderly.

Integration of the B-Cell Receptor Antigen Neurabin-I/SAMD14 Into an Antibody Format as New Therapeutic Approach for the Treatment of Primary CNS Lymphoma

Recently, neurabin-I and SAMD14 have been described as the autoantigenic target of approximately 66% of B-cell receptors (BCRs) of primary central nervous system lymphomas (PCNSL). Neurabin-I and SAMD14 share a highly homologous SAM domain that becomes immunogenic after atypical hyper-N-glycosylation (SAMD14 at ASN339 and neurabin-I at ASN1277). This post-translational modification of neurabin-I and SAMD14 seems to lead to a chronic immune reaction with B-cell receptor activation contributing to lymphoma genesis of PCNSLs. The selective tropism of PCNSL to the CNS corresponds well to the neurabin-I and SAMD14 protein expression pattern. When conjugated to Pseudomonas Exotoxin A (ETA´), the PCNSL reactive epitope exerts cytotoxic effects on lymphoma cells expressing a SAMD14/neurabin-I reactive BCR. Thus, the reactive epitopes of SAMD14/neurabin-I might be useful to establish additional therapeutic strategies against PCNSL. To test this possibility, we integrated the PCNSL-reactive epitope of SAMD14/neurabin-I into a heavy-chain-only Fab antibody format in substitution of the variable region. Specific binding of the prokaryotically produced SAMD14/neurabin-I Fab-antibody to lymphoma cells and their internalization were determined by flow cytometry. Since no established EBV-negative PCNSL cell line exists, we used the ABC-DLBCL cell lines OCI-Ly3 and U2932, which were transfected to express a SAMD14/neurabin-I reactive BCR. The SAMD14/neurabin-I Fab antibody bound specifically to DLBCL cells expressing a BCR with reactivity to SAMD14/neurabin-I and not to unmanipulated DLBCL cell lines. Eukaryotically produced full-length IgG antibodies are well established as immunotherapy format. Therefore, the PCNSL-reactive epitope of SAMD14/neurabin-I was cloned into a full-length IgG1 format replacing the variable domains of the light and heavy chains. The IgG1-format SAMD14/neurabin-I construct was found to specifically bind to target lymphoma cells expressing a SAMD14/neurabin-I reactive B cell receptor. In addition, it induced dose-dependent relative cytotoxicity against these lymphoma cells when incubated with PBMCs. Control DLBCL cells are not affected at any tested concentration. When integrated into the Fab-format and IgG1-format, the PCNSL-reactive epitope of SAMD14/neurabin-I functions as B-cell receptor Antigen for Reverse targeting (BAR). In particular, the IgG1-format BAR-body approach represents a very attractive therapeutic format for the treatment of PCNSLs, considering its specificity against SAMD14/neurabin-I reactive BCRs and the well-known pharmacodynamic properties of IgG antibodies.

Consecutive single-institution case series of primary central nervous system lymphoma treated by R-MPV or high-dose methotrexate monotherapy

OBJECTIVE

The optimal regimen for use of high dose-methotrexate-based chemotherapy in primary central nervous system lymphoma is still under debate. We conducted a retrospective study to evaluate the treatment outcome of a combination immunochemotherapy consisting of rituximab, methotrexate, procarbazine and vincristine followed by with or without whole brain radiotherapy and consolidation cytarabine, in comparison with high dose-methotrexate monotherapy followed by full dose whole brain radiotherapy.

METHODS

Newly diagnosed primary central nervous system lymphoma patients treated with either rituximab, methotrexate, procarbazine and vincristine or high dose-methotrexate in Kyorin University Hospital were identified, and the response rates and survival were compared. Toxicities, post-treatment transition of Mini-Mental State Examination, Karnofsky performance status score, Fazekas scale and prognostic factors were analysed in the rituximab, methotrexate, procarbazine and vincristine group.

RESULTS

Ninety-five patients treated with rituximab, methotrexate, procarbazine and vincristine (n = 39) or high dose-methotrexate (n = 56) were analysed. The complete response/complete response unconfirmed rate was significantly higher in the rituximab, methotrexate, procarbazine and vincristine group (74.4 vs. 15.4%, P < 0.001). Accordingly, both median progression-free survival and overall survival were significantly longer in the rituximab, methotrexate, procarbazine and vincristine group (median progression-free survival: unreached vs. 14.75 months, P < 0.001) (median overall survival: unreached vs. 63.15 months, P = 0.005). Although the rate of grade 3/4 hematologic toxicities was high both during rituximab, methotrexate, procarbazine and vincristine and consolidation cytarabine, the rate of grade 3/4 infections was low, and no treatment related deaths were observed. Deterioration in Karnofsky performance status or Mini-Mental State Examination was rare, except on disease recurrence. Although whole brain radiotherapy was associated with Fazekas scale deterioration, its association with Karnofsky performance status or Mini-Mental State Examination deterioration was not significant.

CONCLUSIONS

Rituximab, methotrexate, procarbazine and vincristine was apparently promising in comparison with high dose-methotrexate monotherapy with manageable toxicity in this retrospective study, and further investigation is warranted.

Vitreous levels of interleukin-35 as a prognostic factor in B-cell vitreoretinal lymphoma

Vitreoretinal lymphoma (VRL) is a rare disease of B-cell origin with poor prognosis. Regulatory cytokines promote tumor development by suppressing antitumor immunity in several cancer types, including B-cell malignancies. To identify the regulatory cytokines associated with poor prognosis in patients with B-cell VRL, we determined the regulatory cytokines profiles in the vitreous humor of patients with VRL. This retrospective study included 22 patients with VRL, 24 with non-infectious uveitis (NIU), and 20 with idiopathic epiretinal membrane (control). Vitreous concentrations of regulatory cytokines were assessed using a cytometric beads assay and association with clinical data was examined. IL-35 and soluble IL-2 receptor α levels were significantly higher in patients with VRL and NIU than those in the control group. The 5-year overall survival (OS) rates for the group with high intravitreal IL-35 was significantly poorer than those for the group with low intravitreal IL-35, who were diagnosed with VRL at the onset (P = 0.024, log-rank test). The 5-year OS rates with intravitreal IL-35 levels above and below the median were 40.0% and 83.3%, respectively. Our results suggest that high intravitreal IL-35 levels indicate poor prognosis for patients diagnosed with B-cell VRL at the onset.

Short and long-term evaluation of the impact of proton minibeam radiation therapy on motor, emotional and cognitive functions

Radiotherapy (RT) is one of the most frequently used methods for cancer treatment. Despite remarkable advancements in RT techniquesthe treatment of radioresistant tumours (i.e. high-grade gliomas) is not yet satisfactory. Finding novel approaches less damaging for normal tissues is of utmost importance. This would make it possible to increase the dose applied to tumours, resulting in an improvement in the cure rate. Along this line, proton minibeam radiation therapy (pMBRT) is a novel strategy that allows the spatial modulation of the dose, leading to minimal damage to brain structures compared to a high dose (25 Gy in one fraction) of standard proton therapy (PT). The aim of the present study was to evaluate whether pMBRT also preserves important cerebral functions. Comprehensive longitudinal behavioural studies were performed in irradiated (peak dose of 57 Gy in one fraction) and control rats to evaluate the impact of pMBRT on motor function (motor coordination, muscular tonus, and locomotor activity), emotional function (anxiety, fear, motivation, and impulsivity), and cognitive function (learning, memory, temporal processing, and decision making). The evaluations, which were conducted over a period of 10 months, showed no significant motor or emotional dysfunction in pMBRT-irradiated rats compared with control animals. Concerning cognitive functions, similar performance was observed between the groups, although some slight learning delays might be present in some of the tests in the long term after irradiation. This study shows the minimal impact of pMBRT on the normal brain at the functional level.

Complete response to therapy: why do primary central nervous system lymphoma patients not return to work?

PURPOSE

Although primary central nervous system lymphomas (PCNSL) represent extremely aggressive brain tumours, high-dose methotrexate in combination with other chemotherapeutic agents has resulted in long-term disease control in a substantial fraction of patients. Advances in treatment efficacy with longer survival resulted in a focus on additional outcome measures such as quality of life (QoL) and neurocognition. Despite recent evidence of return to work as an important aspect of patients' QoL, little is known about occupational reintegration in PCNSL long-term survivors. This study aimed to detect specific characteristics of patients who successfully resumed work after complete response to therapy.

METHODS

Patients with ongoing complete response to therapy completed a test battery capturing neurocognition, social integration, QoL and psychological burden. Of 25 patients who had been in regular employment before diagnosis only eight returned to work after treatment (32%).

RESULTS

Patients who resumed work rated important aspects of their QoL and social integration as higher and suffered less from symptoms affecting QoL than patients who did not resume work. Also, the subjective confidence in their ability to work was higher in patients who resumed work, but independent predictors of return to work were not found in logistic regression analyses.

CONCLUSION

Occupational (re)integration is of clinical relevance in PCNSL patients after complete response to therapy. Due to the small size of our cohort the present results should be considered an exploratory first step. Return to work might be a crucial aspect of QoL and (re)integration into society after cure of PCNSL.

Consolidation Therapy in Primary Central Nervous System Lymphoma

OPINION STATEMENT

Primary central nervous system lymphoma is a complex disease with no agreed-upon standard-of-care therapy. Induction therapy involves multiagent chemotherapy based on high-dose methotrexate, with several regimens available. We have a preference for a regimen using rituximab, methotrexate (3.5 g/m2), procarbazine, and vincristine (R-MPV) for initial induction therapy, given the favorable balance between toxicities and very high response rates (80-90%), which allow for decreasing disease burden and increasing the effectiveness of consolidation treatments. However, in the absence of consolidation therapies, R-MPV is not an effective regimen to achieve long-term remission.Based on high rates of long-term remission, our first choice for consolidation therapy is high-dose chemotherapy with autologous stem-cell transplant using thiotepa, busulfan, and cyclophosphamide as a myeloablative regimen, with a curative intent. This typically applies to patients with a favorable performance status at the end of induction, typically with ECOG performance status of 2 or better, adequate organ function, and age younger than 70. Patients with a high transplant-related mortality risk may still be considered for milder myeloablative regimens such as carmustine/thiotepa.For patients who are not transplant candidates, we typically offer consolidation with reduced dose whole-brain radiation therapy (WBRT) (23.4 Gy), which seems to be associated with lower risks of neurotoxicity as compared with higher doses of radiation. For patients who are not transplant candidates and that do not accept the risk of cognitive decline from the radiotherapy, we typically offer consolidation high-dose cytarabine, provided the patient understands the high risk of relapse. For these patients, a clinical trial is strongly recommended.

New Insights Into Immunological Therapy for Retinal Disorders

In the twentieth century, a conspicuous lack of effective treatment strategies existed for managing several retinal disorders, including age-related macular degeneration; diabetic retinopathy (DR); retinopathy of prematurity (ROP); retinitis pigmentosa (RP); uveitis, including Behçet's disease; and vitreoretinal lymphoma (VRL). However, in the first decade of this century, advances in biomedicine have provided new treatment strategies in the field of ophthalmology, particularly biologics that target vascular endothelial growth factor or tumor necrosis factor (TNF)-α. Furthermore, clinical trials on gene therapy specifically for patients with autosomal recessive or X-linked RP have commenced. The overall survival rates of patients with VRL have improved, owing to earlier diagnoses and better treatment strategies. However, some unresolved problems remain such as primary or secondary non-response to biologics or chemotherapy, and the lack of adequate strategies for treating most RP patients. In this review, we provide an overview of the immunological mechanisms of the eye under normal conditions and in several retinal disorders, including uveitis, DR, ROP, RP, and VRL. In addition, we discuss recent studies that describe the inflammatory responses that occur during the course of these retinal disorders to provide new insights into their diagnosis and treatment.

CXCR4-Targeted PET Imaging of Central Nervous System B-Cell Lymphoma

C-X-C chemokine receptor 4 (CXCR4) is a transmembrane chemokine receptor involved in growth, survival, and dissemination of cancer, including aggressive B-cell lymphoma. MRI is the standard imaging technology for central nervous system (CNS) involvement of B-cell lymphoma and provides high sensitivity but moderate specificity. Therefore, novel molecular and functional imaging strategies are urgently required. Methods: In this proof-of-concept study, 11 patients with lymphoma of the CNS (8 primary and 3 secondary involvement) were imaged with the CXCR4-directed PET tracer ⁶⁸Ga-pentixafor. To evaluate the predictive value of this imaging modality, treatment response, as determined by MRI, was correlated with quantification of CXCR4 expression by ⁶⁸Ga-pentixafor PET in vivo before initiation of treatment in 7 of 11 patients. Results: ⁶⁸Ga-pentixafor PET showed excellent contrast with the surrounding brain parenchyma in all patients with active disease. Furthermore, initial CXCR4 uptake determined by PET correlated with subsequent treatment response as assessed by MRI. Conclusion: ⁶⁸Ga-pentixafor PET represents a novel diagnostic tool for CNS lymphoma with potential implications for theranostic approaches as well as response and risk assessment.

Maintenance of multi-domain neurocognitive functions in patients with newly-diagnosed primary CNS lymphoma after primary cranial radiotherapy combined with methotrexate-based chemotherapy: A preliminary case-series study

Conventional treatment for treating primary central nervous system lymphoma (PCNSL) has consisted of either whole-brain radiotherapy (WBRT) or methotrexate (MTX)-based combined modality therapy. However, delayed cognitive sequelae have emerged as a significant debilitating complication in PCNSL patients. A prospective observational case-series study with prospective assessments of neurocognitive functions (NCFs), neuroimaging, and activities of daily living in newly-diagnosed PCNSL patients was undertaken. A battery of neuropsychological measures, used to evaluate NCFs, is composed of ten standardized NCF tests, representing four domains sensitive to disease and treatment effects (executive function, attention, verbal memory, psychomotor speed), and activities of daily living. A total of 15 patients with newly-diagnosed PCNSL were consecutively enrolled in this study. Comparing the NCF scores between the baseline (before WBRT) and post-treatment (after combined chemoradiation therapy) intervals (Mean = 122.33 days, SD = 34.49, range = 77-196), neurobehavioral outcomes consistently remained improving or stable in almost each domain of NCF. Specifically, the scores on Paced Auditory Serial Addition Test-Revised (PASAT-R) were significantly improved between the baseline and post-chemoradiation assessment. Under the multidisciplinary treatment guidelines for treating patients with newly-diagnosed PCNSL, multi-domain NCF become stabilized and even improved after the course of conformal WBRT combined with or without MTX-based chemotherapy.

Surgery plus adjuvant radiotherapy for primary central nervous system lymphoma

Objective: Recent studies of primary central nervous system lymphoma (PCNSL) have found a positive association between cytoreductive surgery and survival, challenging the traditional notion that surgery is not beneficial and potentially harmful. However, no studies have examined the potential added benefits of adjuvant treatment in the post-operative setting. Here, we investigate survival in PCNSL patients treated with surgery plus radiation therapy (RT).Methods: The Surveillance, Epidemiology, and End-Results Program was used to identify patients with PCNSL from 1995-2013. We retrospectively analyzed the relationship between treatment, prognostic factors, and survival using case-control design. Treatment categories were compared to biopsy alone.Results: We identified 5417 cases. Median survival times for biopsy alone (n = 1824, 34%), biopsy + RT (n = 1460, 27%), surgery alone (n = 1222, 27%), and surgery + RT (n = 911, 17%) were 7, 8, 20, and 27 months, respectively. On multivariable analysis, surgery + RT was associated with improved survival over surgery alone (hazard ratio [HR] = 0.58 [95% confidence interval = 0.53-0.64] vs. HR = 0.71 [0.65-0.77]). Adjuvant RT was associated with improved survival, regardless of the extent of resection. HR's for subtotal resection, gross-total resection, subtotal resection + RT, and gross-total resection + RT were 0.77 (0.66-0.89), 0.66 (0.57-0.76), 0.62 (0.52-0.72), and 0.54 (0.46-0.63), respectively. Survival improved after adjuvant RT in patients under and over 60 years old. All findings were confirmed by multivariable analysis of cause-specific survival.Conclusion: Adjuvant RT was associated with improved survival in PCNSL patients who underwent surgery. Although these data are hypothesis-generating, additional information on neurotoxicity, dosing, and concurrent chemotherapy will be necessary to validate these findings. Cytoreductive surgery for PCNSL is common in the general population, and more studies are needed to assess optimal treatment in the post-operative setting.

Longitudinal cognitive assessment in patients with primary CNS lymphoma treated with induction chemotherapy followed by reduced-dose whole-brain radiotherapy or autologous stem cell transplantation

INTRODUCTION

The standard treatment for primary central nervous system lymphoma (PCNSL) involves induction methotrexate-based chemotherapy with or without consolidation whole brain radiotherapy (WBRT). As WBRT carries a substantial risk for cognitive impairment, alternative consolidation treatments have been used to reduce neurotoxicity, including reduced-dose WBRT (rdWBRT) or high-dose chemotherapy with autologous stem cell transplant (HDC-ASCT). In this study, we characterized cognitive functions in PCNSL patients achieving long-term remission following rdWBRT or HDC-ASCT.

METHODS

PCNSL patients completed cognitive evaluations at diagnosis, post-induction chemotherapy, and yearly up to 5 years following rdWBRT or HDC-ASCT. Quality of life (QoL), white matter (WM) disease, and cortical atrophy (CA) on MRI were assessed at similar intervals.

RESULTS

Performance was impaired on most cognitive tests at diagnosis. Linear mixed model analyses in each group showed statistically significant improvement from baseline up to year 3 in attention/executive functions, graphomotor speed, and memory; however, there was a decline in attention/executive functions and memory after year 3 in both groups. WM abnormalities increased over time in both groups, but more patients treated with rdWBRT developed CA and WM changes. There were no significant longitudinal group differences in cognitive performance or QoL.

CONCLUSIONS

Results indicated improvement in cognitive function up to 3 years post-treatment, but a decline at later time points and an increase in brain structure abnormalities in both groups. The findings suggest that rdWBRT and HDC-ASCT may be associated with delayed neurotoxicity in progression-free patients and underscore the need for long-term follow-up to characterize cognitive dysfunction in PCNSL patients.

Is whole-brain radiotherapy still a standard treatment for primary central nervous system lymphomas?

PURPOSE OF REVIEW

In primary central nervous system lymphomas (PCNSL), optimal therapy remains to be established, and the role of whole-brain radiotherapy (WBRT) is a matter of debate. With radiation alone, transient responses and clinical improvement are frequent, but long-term disease control is exceptional. WBRT has been considered possible consolidation therapy after high-dose methotrexate (HDMTX)-based initial chemotherapy. This strategy has been questioned due to a high risk of delayed neurotoxicity after combined treatment. This review analyses the current role of WBRT in PCNSL.

RECENT FINDINGS

Neither in retrospective analyses nor in randomized trials, an overall survival benefit with WBRT in addition to HDMTX-based initial chemotherapy could be found. On the other hand, a recent randomized trial did not show superiority of consolidation with high-dose chemotherapy followed by autologous stem-cell transplantation to consolidation WBRT after initial HDMTX-based polychemotherapy. This finding, however, is probably due to an intense initial therapy and to a small number of patients having reached consolidation and randomization to WBRT vs. high-dose chemotherapy followed by autologous stem-cell transplantation.

SUMMARY

The current role of WBRT in PCNSL is confined to patients who cannot tolerate chemotherapy or have failed it. WBRT should not routinely be used for consolidation of HDMTX-based chemotherapy due to lack of evidence of efficacy as additional treatment and due to a high risk of neurotoxicity.

Cognitive functioning and health-related quality of life in patients with newly diagnosed primary CNS lymphoma: a systematic review

Incidence of primary CNS lymphoma (PCNSL) is increasing, while prognosis is improving as treatments advance. However, declined cognitive functioning remains a major challenge in the treatment of PCNSL. This cognitive decline, in conjunction with other symptoms caused by the disease or its treatment, or both, can compromise health-related quality of life (HRQOL). The aim of this Review was to give a comprehensive overview on cognitive functioning and HRQOL for patients with PCNSL, including an evaluation of patient-related and treatment-related factors that can influence cognitive functioning and HRQOL. We reviewed the literature for studies on cognitive functioning and HRQOL in newly diagnosed adult patients with PCNSL using MEDLINE/PubMed, Embase, Web of Science, Scopus, Cochrane, PsycINFO, CINAHL EBSCO, and Google Scholar, up to Jan 4, 2018. Articles were selected using predetermined inclusion and exclusion criteria; 42 articles were eligible for inclusion. Findings show that the tumour itself has a great effect on cognitive functioning and HRQOL. Initially, induction chemotherapy results in improvement of cognition and HRQOL in most patients. In the long-term, the addition of whole-brain radiotherapy has a negative effect on cognitive functioning, but the magnitude of this effect is not always clinically relevant. HRQOL scores were worse compared with controls, and worse after combined chemotherapy and radiotherapy when compared with chemotherapy only, particularly in the long term. Therefore, combined chemotherapy and radiotherapy seems to have a negative effect on HRQOL and cognition in patients with PCNSL. Although prolonged progression-free survival is achieved with combined treatment, information on its effect on cognition and HRQOL should be included in clinical decision-making.

Phase 1 investigation of lenalidomide/rituximab plus outcomes of lenalidomide maintenance in relapsed CNS lymphoma

There is an unmet need for effective biological therapies for relapsed central nervous system (CNS) lymphoma. Lenalidomide is active in activated B-cell type diffuse large B-cell lymphoma and rituximab is effective in CNS lymphoma. These observations are the basis for this first trial of an immunomodulatory drug as monotherapy in CNS lymphoma, and, in patients with inadequate responses to lenalidomide, with rituximab. In an independent cohort, we evaluated lenalidomide maintenance after salvage with high-dose methotrexate or focal irradiation in relapsed primary CNS lymphoma (PCNSL). We determined safety, efficacy, and cerebrospinal fluid (CSF) penetration of lenalidomide at 10-, 15-, and 20-mg dose levels in 14 patients with refractory CD20⁺ CNS lymphoma. Nine subjects with relapsed, refractory CNS lymphoma achieved better than partial response with lenalidomide monotherapy, 6 maintained response ≥9 months, and 4 maintained response ≥18 months. Median progression-free survival for lenalidomide/rituximab was 6 months. In the independent cohort, response duration with lenalidomide maintenance after complete responses 2 through 5 were significantly longer than response durations after standard therapy. The CSF/plasma partition coefficient of lenalidomide was ≥20% at 15- and 20-mg dose levels. Change in CSF interleukin-10 at 1 month correlated with clinical response and response duration to lenalidomide. Metabolomic profiling of CSF identified novel biomarkers, including lactate, and implicated indoleamine-2,3 dioxygenase activity with CNS lymphoma progression on lenalidomide. We conclude that lenalidomide penetrates ventricular CSF and is active as monotherapy in relapsed CNS lymphomas. We provide evidence that maintenance lenalidomide potentiates response duration after salvage in relapsed PCNSL and delays whole brain radiotherapy (WBRT). This trial was registered at www.clinicaltrials.gov as #NCT01542918.

Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients 60 Years of Age and Younger: Results of the Intergroup ANOCEF-GOELAMS Randomized Phase II PRECIS Study

PURPOSE

To determine the efficacy and toxicity of chemoimmunotherapy followed by either whole-brain radiotherapy (WBRT) or intensive chemotherapy and autologous stem-cell transplantation (ASCT) as a first-line treatment of primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

Immunocompetent patients (18 to 60 years of age) with untreated PCNSL were randomly assigned to receive WBRT or ASCT as consolidation treatment after induction chemotherapy consisting of two cycles of R-MBVP (rituximab 375 mg/m2 day (D) 1, methotrexate 3 g/m2 D1; D15, VP16 100 mg/m2 D2, BCNU 100 mg/m2 D3, prednisone 60 mg/kg/d D1-D5) followed by two cycles of R-AraC (rituximab 375 mg/m2 D1, cytarabine 3 g/m2 D1 to D2). Intensive chemotherapy consisted of thiotepa (250 mg/m2/d D9; D8; D7), busulfan (8 mg/kg D6 through D4), and cyclophosphamide (60 mg/kg/d D3; D2). WBRT delivered 40 Gy (2 Gy/fraction). The primary end point was 2-year progression-free survival. Cognitive outcome was the main secondary end point. Analysis was intention to treat in a noncomparative phase II trial.

RESULTS

Between October 2008 and February 2014, 140 patients were recruited from 23 French centers. Both WBRT and ASCT met the predetermined threshold (among the first 38 patients in each group, at least 24 patients were alive and disease free at 2 years). The 2-year progression-free survival rates were 63% (95% CI, 49% to 81%) and 87% (95% CI, 77% to 98%) in the WBRT and ASCT arms, respectively. Toxicity deaths were recorded in one and five patients after WBRT and ASCT, respectively. Cognitive impairment was observed after WBRT, whereas cognitive functions were preserved or improved after ASCT.

CONCLUSION

WBRT and ASCT are effective consolidation treatments for patients with PCNSL who are 60 years of age and younger. The efficacy end points tended to favor the ASCT arm. The specific risk of each procedure should be considered.

Primary Central Nervous System Lymphoma: Molecular Pathogenesis and Advances in Treatment

Primary central nervous system lymphoma (PCNSL) is a group of extranodal non-Hodgkin lymphoma that exhibits specific biological characteristics and clinical behavior, with an aggressive disease course and unsatisfactory patient outcomes. It is of great importance to identify aberrant genetic loci and important molecular pathways that might suggest potential targets for new therapeutics and provide prognostic information. In this review, we listed various genetic and epigenetic alterations that are involved in PCNSL pathogenesis. In the aspect of treatment, we summarized the related literatures and evaluated the efficacy of surgery, induction chemotherapy, radiotherapy, intrathecal chemotherapy, and autologous stem cell transplantation in PCNSL. We also proposed the possible new agents for recurrent and relapse PCNSL based on the result of recent clinical researches.

Characteristics and Outcomes of Primary Central Nervous System Lymphoma: A Retrospective Study of 91 Cases in a Chinese Population

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare disease affecting the brain, leptomeninges, spinal cord, cerebrospinal fluid, or vitreoretinal compartment, without evidence of systemic disease. Prognosis is still poor after intensive methotrexate-based chemotherapy.

METHODS

Clinical data of 91 patients treated in a tertiary referral center during a 13-year period were retrospectively reviewed.

RESULTS

The estimated median progression-free survival and overall survival (OS) for the entire cohort were 39.1 months (95% confidence interval [CI], 14.1-64.0 months) and 54.5 months (95% CI, 28.9-80.1 months), respectively. Estimated 5-year progression-free survival and OS were 37.0% ± 6.5% and 47.5% ± 7.5%. Survival was associated with cycles of methotrexate only in multivariate analysis. Seventy-four patients received methotrexate-based chemotherapy after diagnosis. Thirty-nine patients experienced disease progression. Patients with relapsed/refractory disease had a poor survival, with median second OS (calculated from the date of first disease progression to the time of death from any cause) being 7.2 months (95% CI, 2.5-12.00 months). Three patients responded to ibrutinib after disease progression and incurred no fungal infection.

CONCLUSIONS

The outcomes of patients with PCNSL treated in our cohort are still poor. Relapse or refractory PCNSL and those not tolerating aggressive chemotherapy urgently require new approaches to improve their still dismal prognosis. Novel agents such as ibrutinib have shown promising clinical activity. Future studies should focus on the predictive biomarkers for the treatment of PCNSL with novel agents to provide precision medicine for PCNSL.

Primary Central Nervous System Lymphoma

PURPOSE OF REVIEW

Primary central nervous system (CNS) lymphoma is a rare and aggressive extranodal non-Hodgkin lymphoma confined to the brain, eyes, spinal cord, or leptomeninges without systemic involvement. This article provides an overview of the clinical features, diagnosis, and management of primary CNS lymphoma in patients who are immunocompetent, focusing on recent advances in treatment.

RECENT FINDINGS

Primary CNS lymphoma is sensitive to radiation therapy; however, whole-brain radiation therapy inadequately controls the disease when used alone and causes delayed neurotoxicity with significant neurocognitive impairment, especially in patients who are elderly. A number of clinical trials have demonstrated durable disease control and less neurotoxicity with methotrexate-based induction chemotherapy with or without autologous stem cell transplantation or reduced-dose whole-brain radiation therapy.

SUMMARY

Prompt diagnosis and initiation of treatment are vital to improving clinical outcomes in patients with primary CNS lymphoma. The optimal treatment has yet to be defined, but high-dose methotrexate-based induction chemotherapy is considered standard for newly diagnosed primary CNS lymphoma. Ongoing randomized trials will attempt to address the roles of rituximab and consolidative treatment using autologous stem cell transplantation or reduced-dose whole-brain radiation therapy. Despite high tumor response rates to initial treatment, many patients will relapse. The choice of salvage treatment will depend on age, previous treatment and response, performance status, and comorbidities at the time of relapse.