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

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.

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.

Primary CNS Lymphomas: Challenges in Diagnosis and Monitoring

Primary Central Nervous System Lymphoma (PCNSL) is a rare neoplasm that can involve brain, eye, leptomeninges, and rarely spinal cord. PCNSL lesions most typically enhance homogeneously on T1-weighted magnetic resonance imaging (MRI) and appear T2-hypointense, but high variability in MRI features is commonly encountered. Neurological symptoms and MRI findings may mimic high grade gliomas (HGGs), tumefactive demyelinating lesions (TDLs), or infectious and granulomatous diseases. Advanced MRI techniques (MR diffusion, spectroscopy, and perfusion) and metabolic imaging, such as Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) or amino acid PET (usually employing methionine), may be useful in distinguishing these different entities and monitoring the disease course. Moreover, emerging data suggest a role for cerebrospinal fluid (CSF) markers in predicting prognosis and response to treatments. In this review, we will address the challenges in PCNSL diagnosis, assessment of response to treatments, and evaluation of potential neurotoxicity related to chemotherapy and radiotherapy.

Challenges and prospects in the diagnosis and treatment of primary central nervous system lymphoma

Introduction: Primary central nervous system lymphoma (PCNSL) retains peculiar biological and clinical characteristics and a worse prognosis with respect to other comparable lymphomas. The need for high doses of chemotherapy to achieve valid drug concentrations in cerebral tissues and/or radiotherapy results in severe treatment-related toxicities, mainly neurologic, which are frequently as disabling as the disease itself.Areas covered: Several emerging combined therapies are addressed that focus on treating PCNSL. The prognosis has improved in the last years but several questions remain unanswered and the research of more effective therapies goes on. Information and data were obtained from direct authors' experience and a PubMed search of recent peer-reviewed original articles, review articles, and clinical guidelines.Expert commentary: The substantial progress observed in PCNSL has to be ascribed to a carefully combination of standard chemotherapeutic drugs. High-dose methotrexate-based polychemotherapy followed by mainteinance therapy offers one of the best chances to control the disease. Major issues that deserve many efforts by researchers are the definition of optimal consolidation treatment and a shared management of specific conditions such as elderly population and intra-ocular localization.

The possible role of maintenance treatment for primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive brain tumor. The prognosis is poor, with high rates of relapse and disease progression after treatment. In addition, PCNSL affects a largely older population, so that a significant proportion of patients are ineligible for intensive therapies and high-dose chemotherapy. The elderly patients are also susceptible to the accelerated and detrimental cognitive side effects of whole-brain irradiation which is an alternative consolidation to high-dose chemotherapy. Maintenance therapy has been shown to be a promising strategy to prolong remission time in other hematopoietic malignancies. Herein, we discuss the place of maintenance treatment in PCNSL in view of perspective obtained from hematological malignancies and non-Hodgkin's lymphoma.

Long-term survivors of primary central nervous system lymphoma

Objective

In this study, we provide long-term outcome data of patients with primary central nervous system lymphoma.

Methods

The long-term outcomes of PCNSL patients diagnosed between 1982 and 2006 were reviewed. Neurological late neurotoxicity symptoms, neuroradiological brain atrophy and leukoencephalopathy were evaluated. Surviving patients completed the Quality of Life Questionnaire-30 and Brain Cancer Module-20. The differences in overall survival were assessed using the Kaplan-Meier method and log-rank test. The differences between groups in terms of each investigated parameter were analyzed using the Wilcoxon signed-rank test.

Results

Among 112 PCNSL patients, there were 33 (29.4%) long-term (> 5 years) survivors. The median survival of all long-term survivors was 105.7 months; of these, 8 (7.1%) were alive at the latest follow-up, with a mean survival time of 170.2 months (range, 121.8–286.4). Clinical assessment revealed severe neurotoxicity in 14 patients (42.4%), moderate neurotoxicity in 5 (15.1%), and normal status in 14 (42.4%). Correlations were seen between the neuroradiological imaging score changes and neurocognitive condition (P=0.0001), neurocognitive condition and the whole brain irradiation dose (P=0.0004), and atrophy and the whole brain irradiation dose (P=0.0035).

Conclusions

A more severe clinical condition was found to be associated with increasing age and whole brain irradiation dose in long-term survivors with PCNSL.

Therapy of primary CNS lymphoma: role of intensity, radiation, and novel agents

Primary central nervous system (CNS) lymphomas represent a subgroup of malignancies with specific characteristics, an aggressive course, and unsatisfactory outcome in contrast with other lymphomas comparable for tumor burden and histological type. Despite the high sensitivity to conventional chemotherapy and radiotherapy, remissions are frequently short lasting. Treatment efficacy is limited by several factors, including the biology and microenvironment of this malignancy and the "protective" effect of the blood-brain barrier, which limits the access of most drugs to the CNS. Patients who survive are at high risk of developing treatment-related toxicity, mainly disabling neurotoxicity, raising the question of how to balance therapy intensification with the control of side effects. Recent therapeutic progress and effective international cooperation have resulted in a significantly improved outcome over the past 2 decades, with a higher proportion of patients receiving treatment with curative intent. Actual front-line therapy consists of high-dose methotrexate-based polychemotherapy. Evidence supporting the addition of an alkylating agent and rituximab is growing, and a recent randomized trial demonstrated that the combination of methotrexate, cytarabine, thiotepa, and rituximab (MATRix regimen) is associated with a significantly better overall survival. Whole-brain irradiation and high-dose chemotherapy supported by autologous stem cell transplantation are 2 effective consolidation strategies in patients with a disease responsive to induction chemotherapy. Different strategies such as alkylating maintenance, conservative radiotherapy, and nonmyeloablative consolidation are being addressed in large randomized trials and a more accurate knowledge of the molecular and biological characteristics of this malignancy are leading to the development of target therapies in refractory/relapsing patients, with the overall aim to incorporate new active agents as part of first-line treatment. The pros and cons of these approaches together with the best candidates for each therapy are outlined in this article.

Whole-brain radiotherapy or autologous stem-cell transplantation as consolidation strategies after high-dose methotrexate-based chemoimmunotherapy in patients with primary CNS lymphoma: results of the second randomisation of the International Extranodal Lymphoma Study Group-32 phase 2 trial

BACKGROUND

The International Extranodal Lymphoma Study Group-32 (IELSG32) trial is an international randomised phase 2 study that addresses two key clinical questions in the treatment of patients with newly diagnosed primary CNS lymphoma. Results of the first randomisation have demonstrated that methotrexate, cytarabine, thiotepa, and rituximab (called the MATRix regimen) is the induction combination associated with significantly better outcome compared with the other induction combinations tested. Here, we report the results of the second randomisation that addresses the efficacy of myeloablative chemotherapy supported by autologous stem-cell transplantation (ASCT), as an alternative to whole-brain radiotherapy (WBRT), as consolidation after high-dose-methotrexate-based chemoimmunotherapy.

METHODS

HIV-negative patients (aged 18-70 years) with newly diagnosed primary CNS lymphoma and an Eastern Cooperative Oncology Group performance status of 0-3 were randomly assigned to receive four courses of methotrexate 3·5 g/m2 on day 1 plus cytarabine 2 g/m2 twice daily on days 2 and 3 (group A); or the same combination plus two doses of rituximab 375 mg/m2 on days -5 and 0 (group B); or the same methotrexate-cytarabine-rituximab combination plus thiotepa 30 mg/m2 on day 4 (group C), with the three groups repeating treatment every 3 weeks. Patients with responsive or stable disease after induction treatment, with adequate autologous peripheral blood stem-cell collection, and without persistent iatrogenic side-effects, were eligible for the second randomisation between WBRT (photons of 4-10 MeV; five fractions per week; fraction size 180 cGy; started within 4 weeks from the last induction course; group D) and carmustine-thiotepa conditioned ASCT (carmustine 400 mg/m2 on day -6, and thiotepa 5 mg/kg every 12 h on days -5 and -4, followed by reinfusion of autologous peripheral blood stem cells; group E). A permuted block randomised design was adopted for both randomisations, and a computer-generated randomisation list was used within each stratum. No masking after assignment to intervention was adopted. The primary endpoint was 2-year progression-free survival, with induction group and response to induction chemotherapy as stratification parameters. Analyses were done on a modified intention-to-treat basis. This study is registered with ClinicalTrials.gov, number NCT01011920.

FINDINGS

Between Feb 19, 2010, and Aug 27, 2014, 227 patients were recruited from 53 centres in five countries. 219 of 227 enrolled patients were assessable. Of the 122 patients eligible for the second randomisation, 118 patients were randomly assigned to WBRT or ASCT (59 patients per group) and constitute the study population. WBRT and ASCT were both effective, and achieved the predetermined efficacy threshold of at least 40 progression-free survivors at 2 years among the first 52 patients in both groups D and E. There were no significant differences in 2-year progression-free survival between WBRT and ASCT: 80% (95% CI 70-90) in group D and 69% (59-79) in group E (hazard ratio 1·50, 95% CI 0·83-2·71; p=0·17). Both consolidation therapies were well tolerated. Grade 4 non-haematological toxicity was uncommon; as expected, haematological toxicity was more common in patients treated with ASCT than in those who received WBRT. Two toxic deaths (infections) were recorded, both in patients who received ASCT.

INTERPRETATION

WBRT and ASCT are both feasible and effective as consolidation therapies after high-dose methotrexate-based chemoimmunotherapy in patients aged 70 years or younger with primary CNS lymphoma. The risks and implications of cognitive impairment after WBRT should be considered at the time of therapeutic decision.

FUNDING

Agenzia Italiana del Farmaco, Cancer Research UK, Oncosuisse, and Swiss National Science Foundation.

Neurocognitive sparing of desktop microbeam irradiation

BACKGROUND

Normal tissue toxicity is the dose-limiting side effect of radiotherapy. Spatial fractionation irradiation techniques, like microbeam radiotherapy (MRT), have shown promising results in sparing the normal brain tissue. Most MRT studies have been conducted at synchrotron facilities. With the aim to make this promising treatment more available, we have built the first desktop image-guided MRT device based on carbon nanotube x-ray technology. In the current study, our purpose was to evaluate the effects of MRT on the rodent normal brain tissue using our device and compare it with the effect of the integrated equivalent homogenous dose.

METHODS

Twenty-four, 8-week-old male C57BL/6 J mice were randomly assigned to three groups: MRT, broad-beam (BB) and sham. The hippocampal region was irradiated with two parallel microbeams in the MRT group (beam width = 300 μm, center-to-center = 900 μm, 160 kVp). The BB group received the equivalent integral dose in the same area of their brain. Rotarod, marble burying and open-field activity tests were done pre- and every month post-irradiation up until 8 months to evaluate the cognitive changes and potential irradiation side effects on normal brain tissue. The open-field activity test was substituted by Barnes maze test at 8th month. A multilevel model, random coefficients approach was used to evaluate the longitudinal and temporal differences among treatment groups.

RESULTS

We found significant differences between BB group as compared to the microbeam-treated and sham mice in the number of buried marble and duration of the locomotion around the open-field arena than shams. Barnes maze revealed that BB mice had a lower capacity for spatial learning than MRT and shams. Mice in the BB group tend to gain weight at the slower pace than shams. No meaningful differences were found between MRT and sham up until 8-month follow-up using our measurements.

CONCLUSIONS

Applying MRT with our newly developed prototype compact CNT-based image-guided MRT system utilizing the current irradiation protocol can better preserve the integrity of normal brain tissue. Consequently, it enables applying higher irradiation dose that promises better tumor control. Further studies are required to evaluate the full extent effects of this novel modality.

Radiation therapy for older patients with brain tumors

The incidence of brain tumors in the elderly population has increased over the last few decades. Current treatment includes surgery, radiotherapy and chemotherapy, but the optimal management of older patients with brain tumors remains a matter of debate, since aggressive radiation treatments in this population may be associated with high risks of neurological toxicity and deterioration of quality of life. For such patients, a careful clinical status assessment is mandatory both for clinical decision making and for designing randomized trials to adequately evaluate the optimal combination of radiotherapy and chemotherapy.

Several randomized studies have demonstrated the efficacy and safety of chemotherapy for patients with glioblastoma or lymphoma; however, the use of radiotherapy given in association with chemotherapy or as salvage therapy remains an effective treatment option associated with survival benefit. Stereotactic techniques are increasingly used for the treatment of patients with brain metastases and benign tumors, including pituitary adenomas, meningiomas and acoustic neuromas. Although no randomized trials have proven the superiority of SRS over other radiation techniques in older patients with brain metastases or benign brain tumors, data extracted from recent randomized studies and large retrospective series suggest that SRS is an effective approach in such patients associated with survival advantages and toxicity profile similar to those observed in young adults. Future trials need to investigate the optimal radiation techniques and dose/fractionation schedules in older patients with brain tumors with regard to clinical outcomes, neurocognitive function, and quality of life.

The Challenge of Primary Central Nervous System Lymphoma

Primary central nervous system (CNS) lymphoma is a challenging subtypes of aggressive non-Hodgkin lymphoma. Emerging clinical data suggest that optimized outcomes are achieved with dose-intensive CNS-penetrant chemotherapy and avoiding whole brain radiotherapy. Anti-CD20 antibody-based immunotherapy as a component of high-dose methotrexate-based induction programs may contribute to improved outcomes. An accumulation of insights into the molecular and cellular basis of disease pathogenesis is providing a foundation for the generation of molecular tools to facilitate diagnosis as well as a roadmap for integration of targeted therapy within the developing therapeutic armamentarium for this challenging brain tumor.

Angiogenesis inhibitors in tackling recurrent glioblastoma

INTRODUCTION

Despite aggressive multimodality treatment of glioblastoma, outcome remains poor and patients mostly die of local recurrences. Besides reoperation and occasionally reirradiation, systemic treatment of recurrent glioblastoma consists of alkylating chemotherapy (lomustine, temozolomide), bevacizumab and combinations thereof. Unfortunately, antiangiogenic agents failed to improve survival either as a monotherapy or in combination treatments. This review provides current insights into tumor-derived escape mechanisms and other areas of treatment failure of antiangiogenic agents in glioblastoma. Areas covered: We summarize the current literature on antiangiogenic agents in the treatment of glioblastoma, with a focus on recurrent disease. A literature search was performed using the terms 'glioblastoma', 'bevacizumab', 'antiangiogenic', 'angiogenesis', 'resistance', 'radiotherapy', 'chemotherapy' and derivations thereof. Expert commentary: New insights in glioma neoangiogenesis, increasing understanding of vascular pathway escape mechanisms, and upcoming immunotherapy approaches might revitalize the therapeutic potential of antiangiogenic agents against glioblastoma, although with a different treatment intention. The combination of antiangiogenic approaches with or without radiotherapy might still hold promise to complement the therapeutic armamentarium of fighting glioblastoma.

Early whole brain radiotherapy in primary CNS lymphoma: negative impact on quality of life in the randomized G-PCNSL-SG1 trial

PURPOSE

In the randomized G-PCNSL-SG-1 trial, the addition of whole brain radiotherapy (45 Gy) to high-dose methotrexate (HD-MTX)-based chemotherapy (early WBRT arm) did not prolong overall survival (OS) as compared to HD-MTX-based chemotherapy alone (no early WBRT arm) in primary CNS lymphoma (PCNSL) patients. To determine whether WBRT might lead to quality of life (QoL)-relevant late neurotoxicity, this trial prospectively monitored QoL.

METHODS

QoL measurements were performed using the EORTC-QLQ-C30 and BN20 questionnaires and combined with repeated Mini Mental State Examinations (MMSE). Exploratory data analysis included the 318 patients in the per-protocol population.

RESULTS

In year 2 after randomization, cognitive functioning and global health status were reduced in the early WBRT arm as compared to the no early WBRT arm (p = 0.004 and p = 0.022, respectively). Also, fatigue (p = 0.037), appetite loss (p = 0.006) and hair loss (p = 0.002) were more intense in the early WBRT arm. MMSE testing revealed lower values (p = 0.002) in the early WBRT arm. A mixed model analysis of longitudinal data additionally showed differences favoring the no early WBRT arm in 15 of 26 dimensions of QoL.

CONCLUSIONS

The analysis of subjective QoL questionnaires and objective MMSE testing revealed that QoL and cognition were conserved in the arm without early WBRT. Thus, even though it was an exploratory analysis, the results of G-PCNSL-SG1 challenge the place of WBRT in the primary therapy of PCNSL.

What Do We Know About Psychological Outcomes of Lymphoma in Adults?

Abstract. The goal of this review is to present the results of research on the influence of lymphoma on patients’ emotional status and cognitive functioning. A literature search was conducted to identify articles in English that investigated short- and long-term psychological outcomes of lymphoma and lymphoma treatment. Studies published prior to July 2016 were located by an electronic search using relevant databases such as ScienceDirect and PubMed. The search terms used included both medical subject headings and keywords such as “Hodgkin lymphoma,” “non-Hodgkin lymphoma,” “therapy,” “treatment,” “malignant,” “psychology,” “cognitive function,” “emotion,” “psychological adaptation,” “depression,” and “anxiety.” The retrieved publications were independently evaluated by two reviewers. Articles were selected based on the applicable titles and abstracts. The lists of eligible publications were compared and disagreements were resolved by discussion. Of the 1,418 articles identified in the search, we chose 39 publications, which in our opinion could be interesting or useful for psychologists. Studies show that lymphoma and its treatment lead to severe distress. Thirty-six percent of patients manifest symptoms of anxiety and depression, which are most often associated with the so-called “B-symptoms,” which mark poor prognosis or with side effects of chemotherapy such as nausea or vomiting. Reports also indicate that lymphoma patients may develop mild to severe cognitive decline. Its manifestations may range from benign problems with attention, thinking, and memory to severe cognitive impairment, that is, subcortical dementia. The etiology of intellectual deterioration in lymphoma has not been well described yet, but it may be related to the disease process or to the treatment. Additionally, literature demonstrates that lymphoma may lead to adverse changes in patient’s professional life such as resignation or early retirement.

PD-1 blockade with nivolumab in relapsed/refractory primary central nervous system and testicular lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) and primary testicular lymphoma (PTL) are rare extranodal large B-cell lymphomas with similar genetic signatures. There are no standard-of-care treatment options for patients with relapsed and refractory PCNSL and PTL, and the overall prognosis is poor. PCNSLs and PTLs exhibit frequent 9p24.1 copy-number alterations and infrequent translocations of 9p24.1 and associated increased expression of the programmed cell death protein 1 (PD-1) ligands, PD-L1 and PD-L2. The activity of PD-1 blockade in other lymphomas with 9p24.1 alterations prompted us to test the efficacy of the anti-PD1 antibody, nivolumab, in 4 patients with relapsed/refractory PCNSL and 1 patient with CNS relapse of PTL. All 5 patients had clinical and radiographic responses to PD-1 blockade, and 3 patients remain progression-free at 13⁺ to 17⁺ months. Our data suggest that nivolumab is active in relapsed/refractory PCNSL and PTL and support further investigation of PD-1 blockade in these diseases.

Case-based review: primary central nervous system lymphoma

Primary CNS lymphoma (PCNSL) is a rare diffuse large B-cell lymphoma originating within the central nervous system. The overall incidence of PCNSL is rising, particularly in the elderly population. Immunosuppression is a strong risk factor, but most patients with this tumor are apparently immunocompetent. Diagnosis of PCNSL can be challenging. Non-invasive or minimally invasive tests such as ophthalmological evaluation and spinal fluid analysis may be useful, but the majority of patients require tumor biopsy for definitive diagnosis. Our knowledge concerning optimum treatment of PCNSL is fragmentary due to paucity of adequately sized trials. Most patients are now initially treated with high-dose-methotrexate-based chemotherapy alone, as the addition of whole-brain radiotherapy at standard doses has not been shown to increase survival and does increase the risk of neurological toxicity. Ongoing trials are addressing issues such as the roles of reduced-dose radiotherapy, the addition of the CD20 antibody rituximab to chemotherapy, high-dose chemotherapy followed by autologous stem cell transplantation, and maintenance therapy in the primary management of PCNSL.

Cognitive function and its relationship to other psychosocial factors in lymphoma survivors

PURPOSE

The purpose of this study was to estimate the prevalence of cognitive disturbance in lymphoma survivors and to explore relationships between cognitive function and other psychosocial factors.

METHODS

A package of standardized questionnaires was sent to 622 lymphoma patients treated at the Ottawa Hospital in the preceding 5 years. Patients with central nervous system involvement were excluded. The questionnaires addressed cognitive function, pain, insomnia, fatigue, and mood. Of the patients in the sampling frame, 54 % responded to the survey and 42 % met inclusion/exclusion criteria. Sixteen percent (99/622) agreed to undergo computerized neuropsychological testing with CNS vital signs (CNSVS). Scores on the objective and subjective cognitive measures were compared to those of a healthy female control group from a previous study.

RESULTS

The lymphoma group scored significantly lower than the controls on a cognitive rating scale (p = .018) and on CNSVS (p = .035). The difference on the CNSVS was primarily due to poorer attention and executive function scores in the lymphoma patients. The patients also had a higher frequency of impairment on both the objective (p = .009) and subjective (p < .001) cognitive measures. Among the lymphoma survivors, fatigue and anxiety were related to subjective cognitive disturbance (p < .001 for both), whereas pain was the only psychosocial measure associated with objective cognitive performance (p < .001).

CONCLUSIONS

These results suggest that cognitive disturbance may be a significant survivorship issue for lymphoma patients and should be more thoroughly investigated in this population.

What is known and unknown about chemotherapy-related cognitive impairment in patients with haematological malignancies and areas of needed research

Cancer-related cognitive impairment (CRCI) is an important clinical problem for cancer patients and survivors. In this review, we summarize studies investigating the occurrence of impaired cognition in patients with haematological malignancies. Most published studies focus on survivors of childhood acute lymphoblastic leukaemia and primary central nervous system lymphoma. We also discuss studies conducted in acute myeloid leukaemia, myelodysplastic syndromes, chronic myeloid leukaemia, Hodgkin lymphoma (HL), non-HL and chronic lymphocytic leukaemia. Although research in this area is still emerging, it appears that a subset of chemotherapy-treated haematological malignancy survivors experience CRCI. Future research should focus on expanding the literature reviewed here with larger studies appropriately powered to assess cognition via objective and subjective measures in a longitudinal fashion to tease apart the impact of disease and the various forms of cancer treatment.

Radiation Effects on Cognitive Function Among Atomic Bomb Survivors Exposed at or After Adolescence

BACKGROUND

The objective of this study was to investigate radiation effects on longitudinal pre-dementia cognitive decline among participants who developed dementia as well as on those who did not develop dementia during follow-up.

METHODS

Measuring cognitive function with the Cognitive Abilities Screening Instrument approximately every 2 years, we followed 1844 atomic bomb survivors participating in the Adult Health Study of the Radiation Effects Research Foundation from 1992 to 2011. Participants were adolescents or older when exposed to between 0 and 4 Gy. Approximately 15% and 40% of participants were exposed to ≥1 Gy and <5 mGy, respectively. At study start, participants were dementia-free and between 60 and 80 years old. Three-quarters of the participants returned after baseline, averaging 8.4 years of follow-up. During follow-up, 313 developed dementia. We used cognitive scores before dementia onset for analysis and a mixed-effects model to estimate radiation effects on longitudinal change of cognition, adjusting for dementia occurrence, age, sex, and education.

RESULTS

Cognition level was significantly associated with age, education, and dementia occurrence but not with radiation dose or sex. Cognitive decline accelerated with increasing age, especially among participants who developed dementia. Neither radiation nor education was significantly associated with the degree of deterioration with age. Radiation did not modify the different cognitive decline by dementia occurrence.

CONCLUSIONS

Radiation did not significantly affect cognition among atomic bomb survivors exposed at or after adolescence.

Fractionation Spares Mice From Radiation-Induced Reductions in Weight Gain But Does Not Prevent Late Oligodendrocyte Lineage Side Effects

PURPOSE

To determine the late effects of fractionated versus single-dose cranial radiation on murine white matter.

METHODS AND MATERIALS

Mice were exposed to 0 Gy, 6 × 6 Gy, or 1 × 20 Gy cranial irradiation at 10 to 12 weeks of age. Endpoints were assessed through 18 months from exposure using immunohistochemistry, electron microscopy, and electrophysiology.

RESULTS

Weight gain was temporarily reduced after irradiation; greater loss was seen after single versus fractionated doses. Oligodendrocyte progenitor cells were reduced early and late after both single and fractionated irradiation. Both protocols also increased myelin g-ratio, reduced the number of nodes of Ranvier, and promoted a shift in the proportion of small, unmyelinated versus large, myelinated axon fibers.

CONCLUSIONS

Fractionation does not adequately spare normal white matter from late radiation side effects.

Partial-brain radiotherapy for primary central nervous system lymphoma: multi-institutional experience

Whole-brain radiotherapy (WBRT) has been an important component of treatment for primary central nervous system lymphoma (PCNSL), but delayed neurotoxicity has been a matter of concern. We have employed partial-brain radiotherapy (PBRT) with wide margins for PCNSL patients with a single lesion or a few lesions. In this study, we evaluated the treatment outcome in PCNSL patients undergoing PBRT. Between 2003 and 2014, 24 patients were treated with PBRT; 16 received high-dose-methotrexate (MTX) -containing chemotherapy before PBRT. Conventional fractionation with a median dose of 54 Gy was used. For reference, 15 patients undergoing MTX-based chemotherapy and WBRT were also analyzed. The 3-year overall survival rate was 60% for all 24 patients undergoing PBRT and 68% for the 16 patients undergoing MTX-based chemotherapy plus PBRT. The 3-year progression-free survival rate was 41% for all 24 patients undergoing PBRT and 36% for the 16 patients undergoing MTX-based chemotherapy. The in-field recurrence rate was 26% and the out-of-field recurrence rate was 15% at 3 years for all 24 patients undergoing PBRT. The rates for in-field recurrence and the out-of-field recurrence were 27% and 21%, respectively, for the 16 patients undergoing MTX-based chemotherapy. CNS-recurrence rates were similar in patients undergoing MTX-based chemotherapy and PBRT to the rates in those undergoing MTX-based chemotherapy and WBRT. Neurocognitive dysfunction developed in 3 of the 16 patients undergoing MTX + PBRT and in 4 of 15 patients undergoing MTX + WBRT (P = 0.68). PBRT seems to be a feasible treatment option for solitary PCNSL. Further investigations are warranted to evaluate the advantages of PBRT over WBRT.

Neurocognitive Deficits After Radiation Therapy for Brain Malignancies

Radiotherapy (RT) has proven to be an effective therapeutic tool in treatment of a wide variety of brain tumors; however, it has a negative impact on quality of life and neurocognitive function. Cognitive dysfunction associated with both the disease and adverse effects of RT is one of the most concerning complication among long-term survivors. The effects of RT to brain can be divided into acute, early delayed, and late delayed. It is, however, the late delayed effects of RT that lead to severe neurological consequences such as minor-to-severe cognitive deficits due to irreversible focal or diffuse necrosis of brain parenchyma. In this review, we discuss current and emerging data regarding the relationship between RT and neurocognitive outcomes, and therapeutic strategies to prevent/treat postradiation neurocognitive deficits.

New approaches in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) has long been associated with an inferior prognosis compared to other aggressive non-Hodgkin's lymphomas (NHLs). However, during the past 10 years an accumulation of clinical experience has demonstrated that long-term progression-free survival (PFS) can be attained in a major proportion of PCNSL patients who receive dose-intensive consolidation chemotherapy and avoid whole brain radiotherapy. One recent approach that has reproducibly demonstrated efficacy for newly diagnosed PCNSL patients is an immunochemotherapy combination regimen used during induction that consists of methotrexate, temozolomide, and rituximab followed by consolidative infusional etoposide plus high-dose cytarabine (EA), administered in first complete remission (CR). Other high-dose chemotherapy-based consolidative regimens have shown efficacy as well. Our goal in this review is to update principles of diagnosis and management as well as data regarding the molecular pathogenesis of PCNSL, information that may constitute a basis for development of more effective therapies required to make additional advances in this phenotype of aggressive NHL.

The role of high-dose myeloablative chemotherapy with haematopoietic stem cell transplantation (HSCT) in children with central nervous system (CNS) tumours: protocol for a systematic review and meta-analysis

OBJECTIVES

The objective of the study is to conduct a systematic review to compare the effects of high-dose chemotherapy (HDCT) with autologous haematopoietic stem cell transplantation (HSCT) versus standard-dose chemotherapy (SDCT) in children with malignant central nervous system (CNS) tumours.

METHODS

Standard systematic review methods aimed at minimising bias will be employed for study identification, selection and data extraction. Ten electronic databases will be searched, along with citation searching and reference checking. Studies assessing the effects of HDCT with HSCT in children with CNS tumours will be included. The outcomes are survival (overall, progression-free, event-free, disease-free), response rates, short- and long-term adverse events and health-related quality of life (HRQoL). Two reviewers will independently screen and select randomised and non-randomised controlled trials and controlled and uncontrolled observational studies for inclusion. Quality assessment will be tailored to the different study designs. Where possible data will be summarised using combined estimates of effect for the hazard ratio for survival outcomes and the risk ratio for response rates. A fixed effect model will be used; sub-group analyses and meta-regression will be used to explore potential sources of heterogeneity between studies.

DISCUSSION

Given the poor prognosis of malignant brain tumours in children in terms of survival and quality of life, this review will help guide clinical practice by summarising the current evidence on the use of high-dose myeloblative chemotherapy with stem cell support in children with CNS tumours.

Primary Diffuse Large B-Cell Lymphoma of Central Nervous System: Is Still Surgery an Unorthodox Treatment?

Primary central nervous system lymphoma (PCNSL) is characterized as an extra-nodal non-Hodgkin lymphoma which develops from the neuraxis. The purpose was to report a case of a patient with a supra-tentorial tumor who underwent subtotal resection of his tumor as his biopsy was not indicative of a PCNSL tumor and had uneventful recovery until his last follow-up. A 42-year-old man was admitted to our department for generalized epileptic seizures. CT and MRI examinations revealed a tumor in his right parietal-occipital lobe that was surrounded by edema and was enhancing after gadolinium administration. The patient underwent a navigation-assisted parieto-occipital craniotomy and posterior parietal transcortical approach for tumor biopsy which was not indicative of PCNSL tumor. The surgical team decided to remove the tumor on site. Histological analysis of the resected specimen showed primary diffuse large B-cell lymphoma. Combined chemotherapy and radiation therapy was applied to the patient, and at his last follow-up (16 months), he is tumor free. In our case as in several other studies during the last decade, the outcome after the surgical resection of a PCNSL tumor in combination to radiation and chemotherapy was unexpectedly good. The role of surgery probably should be reconsidered for single lesion PCNSL tumors.

Predictive value of microRNAs as novel biomarkers in detection of lymphoma

MicroRNAs (miRNAs) have attracted many attentions in lymphoma diagnostic research. The inconsistence of diagnostic performance in these existed literatures leading us to conduct this meta-analysis. In order to have a scientific and reliable study, all related articles were screened from Medline, Embase, CNKI and other databases. The sensitivity and specificity of each involved research were used to plot the summary receiver operator characteristic (SROC) curve and calculate the area under the curve (AUC). The QUADAS-2 tool was applied to estimate the quality of included studies. In addition, Deeks' funnel plot asymmetry test was performed to estimate publication bias. Overall, 14 studies from 6 articles were included to evaluate the whole test performance. The overall pooled results were as follows: sensitivity was 0.91 (95% CI: 0.83-0.95), specificity was 0.84 (95% CI: 0.75-0.90), the AUC was 0.93 (95% CI: 0.91-0.95), positive likelihood ratio-PLR was 5.5 (95% CI: 3.5-8.8), negative likelihood ratio-NLR was 0.11 (95% CI: 0.06-0.21), and diagnostic odds ratio-DOR was 50 (95% CI: 19-128). In summary, results from meta-analysis showed that miRNAs analysis might significantly increase the diagnostic accuracy of lymphoma. Further massive prospective studies still needed to validate our conclusion before clinical application.

Standard chemoradiation for glioblastoma results in progressive brain volume loss

OBJECTIVE

To investigate the effects of chemotherapy and cranial irradiation on normal brain tissue using in vivo neuroimaging in patients with glioblastoma.

METHODS

We used longitudinal MRI to monitor structural brain changes during standard treatment in patients newly diagnosed with glioblastoma. We assessed volumetric and diffusion tensor imaging measures in 14 patients receiving 6 weeks of chemoradiation, followed by up to 6 months of temozolomide chemotherapy alone. We examined changes in whole brain, gray matter (GM), white matter (WM), anterior lateral ventricle, and hippocampal volumes. Normal-appearing GM, WM, and hippocampal analyses were conducted within the hemisphere of lowest/absent tumor burden. We examined diffusion tensor imaging measures within the subventricular zone.

RESULTS

Whole brain (F = 2.41; p = 0.016) and GM (F = 2.13; p = 0.036) volume decreased during treatment, without significant WM volume change. Anterior lateral ventricle volume increased significantly (F = 65.51; p < 0.001). In participants analyzed beyond 23 weeks, mean ventricular volume increased by 42.2% (SE: 8.8%; t = 4.94; p < 0.005). Apparent diffusion coefficient increased within the subventricular zone (F = 7.028; p < 0.001). No significant changes were identified in hippocampal volume.

CONCLUSIONS

We present evidence of significant and progressive treatment-associated structural brain changes in patients with glioblastoma treated with standard chemoradiation. Future studies using longitudinal neuropsychological evaluation are needed to characterize the functional consequences of these structural changes.

Chemotherapy, cognitive impairment and hippocampal toxicity

Cancer therapies can be associated with significant central nervous system (CNS) toxicity. While radiation-induced brain damage has been long recognized both in pediatric and adult cancer patients, CNS toxicity from chemotherapy has only recently been acknowledged. Clinical studies suggest that the most frequent neurotoxic adverse effects associated with chemotherapy include memory and learning deficits, alterations of attention, concentration, processing speed and executive function. Preclinical studies have started to shed light on how chemotherapy targets the CNS both on cellular and molecular levels to disrupt neural function and brain plasticity. Potential mechanisms include direct cellular toxicity, alterations in cellular metabolism, oxidative stress, and induction of pro-inflammatory processes with subsequent disruption of normal cellular and neurological function. Damage to neural progenitor cell populations within germinal zones of the adult CNS has been identified as one of the key mechanisms by which chemotherapy might exert long-lasting and progressive neurotoxic effects. Based on the important role of the hippocampus for maintenance of brain plasticity throughout life, several experimental studies have focused on the study of chemotherapy effects on hippocampal neurogenesis and associated learning and memory. An increasing body of literature from both animal studies and neuroimaging studies in cancer patients suggests a possible relationship between chemotherapy induced hippocampal damage and the spectrum of neurocognitive deficits and mood alterations observed in cancer patients. This review aims to briefly summarize current preclinical and neuroimaging studies that are providing a potential link between the neurotoxic effects of chemotherapy and hippocampal dysfunction, highlighting challenges and future directions in this field of investigation.

Primary CNS lymphoma

Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system is an aggressive malignancy that exhibits unique biological features and characteristic clinical behaviour, with overall long-term survival rates of around 20–40 %. Clinical outcome has improved following the advent of chemoradiation protocols incorporating high-dose methotrexate in the mid-1980s, but disease relapse and adverse neurocognitive sequelae remain major clinical challenges. To address this, investigators have focused on improving drug therapy with novel cytotoxic combinations, monoclonal antibody therapy, and intensive chemotherapy consolidation approaches, in an attempt to improve disease control whilst reducing the requirement for whole-brain radiotherapy. Outcomes for patients that are older, immunocompromised, or have relapsed/refractory disease remain unsatisfactory and there is a paucity of clinical trial data to guide treatment of these groups. This review highlights recent advances in pathobiology, imaging, and clinical management of PCNSL and looks ahead to research priorities for this rare and challenging lymphoid malignancy.

[Primary CNS lymphoma. Progress in the diagnostics and therapy]

BACKGROUND

Some important knowledge has recently been gained on primary central nervous system lymphomas (PCNSL) despite its rarity.

GOAL

This article summarizes the most relevant progress in the diagnostics and therapy of PCNSL and discusses future directions.

MATERIAL AND METHODS

Reference articles in the English language literature were studied with respect to future approaches in PCNSL.

RESULTS

New diagnostic methods in cerebrospinal fluid have been developed to facilitate lymphoma diagnosis; however, their value still has to be validated. A better immunohistological and molecular characterization of PCNSL will probably result in identification of new therapeutic targets. The only phase III trial for PCNSL completed so far did not demonstrate a survival advantage with whole brain irradiation after high-dose methotrexate (HDMTX)-based chemotherapy as compared to chemotherapy alone. The optimal primary chemotherapy has not yet been established due to a lack of results from randomized trials. Non-comparative studies suggest a superiority of combined polychemotherapy over HDMTX monotherapy. Future therapeutic developments are directed towards consolidation of HDMTX-based induction chemotherapy with noncross-resistant conventional chemotherapy or high-dose chemotherapy with autologous stem cell transplantation. An important goal of all therapies for PCNSL is to avoid delayed neurotoxicity.

DISCUSSION

Further improvement of diagnostics and well-designed comparative studies, including new drugs when possible are still needed to define the optimal management of this still frequently prognostically unfavorable disease.

Stereotactic radiosurgery in combination with up-front high-dose methotrexate as a first-line treatment for newly diagnosed primary central nervous system lymphoma

The efficacy of stereotactic radiosurgery (SRS) instead of whole brain radiotherapy (WBRT) following high-dose methotrexate (HD-MTX) for primary central nervous system lymphoma (PCNSL) is unclear. To clarify whether SRS in combination with up-front HD-MTX supplements the effect of HD-MTX in remaining or refractory lesions after initial HD-MTX treatment. The authors conducted a retrospective review for newly diagnosed PCNSL patients who underwent SRS after HD-MTX as a first-line treatment. The local control (LC), the progression-free survival (PFS), the recurrence patterns, the salvage treatments, the overall survival (OS), the Karnofsky Performance Status (KPS), the activities of daily living (ADL) were analyzed as well as radiosurgical parameters. Twenty patients underwent SRS for 51 lesions with the median volume of 0.45 cm(3). The median age at SRS was 67 (range 37-82). The median KPS at SRS was 90. The LC rate at 2 years was 86.0 %, the median PFS after SRS was 17 months, necessitating additional SRS and chemotherapy. The median OS was 52 months. No significant side effects related to SRS were observed. During follow-up period, the good ADL preservation was achieved for 13 months from SRS. Patients with KPS ≥ 90 at SRS demonstrated longer ADL preservation (32 months from SRS). SRS following up-front HD-MTX without WBRT provided excellent LC, acceptable OS and the long ADL preservation period. These benefits may be more emphasized especially in patients with good KPS, but should be validated in a large patient population.

Diagnosis and treatment of primary central nervous system lymphoma: A report of nine cases and literature review

Primary central nervous system lymphoma (PCNSL) is a rare, highly malignant tumor type of the nervous system and is associated with poor prognosis. To investigate the efficacy of current treatment strategies for PCNSL, the present study retrospectively analyzed the clinical and pathological features, imaging results, clinical management, and prognoses of nine patients with PCNSL. Postoperative pathological examination confirmed a diagnosis of lymphoma in all the patients and the adopted treatment regimens were as follows: Stereotactic biopsy in combination with methylprednisolone (MP) and methotrexate (MTX) and/or radiotherapy; craniotomy in combination with dexamethasone or MP and/or radiotherapy; and neuroendoscopic surgery in combination with MP and MTX. The follow-up period was 5-27 months with an average duration of 10.1 months. After the initial three months of follow-up, the clinical symptoms of all the patients were significantly improved, with the tumor disappearing in seven patients and evidently reducing in size in two patients. However, six patients exhibited tumor recurrence, three of whom eventually succumbed to the disease during the follow-up period. Currently, comprehensive treatment strategies based on a combination of stereotactic biopsy, chemotherapy and radiotherapy are recommended for the treatment of PCNSL. However, the effectiveness of these treatments remains unsatisfactory. Thus, future studies are required to investigate methods for improving the efficacy of PCNSL treatment strategies.