The role of additional radiotherapy for primary central nervous system lymphoma

Comparative efficacy and safety of neoadjuvant radiotherapy for patients with borderline resectable, and locally advanced pancreatic ductal adenocarcinoma: a systematic review and network meta-analysis protocol

INTRODUCTION

The optimal dose and treatment modality of neoadjuvant radiotherapy applied for treating borderline resectable and locally advanced pancreatic ductal adenocarcinoma (PDAC) have been debated topics in oncology. The objective of the present network meta-analysis (NMA) is to study and compare the efficacy and safety of neoadjuvant radiotherapy comprehensively using different doses in patients with borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC).

METHODS AND ANALYSIS

Four electronic databases, including PubMed, EMBASE, Cochrane library and Web of science, will be searched thoroughly to identify relevant studies published from 2006 to October 2020. Electronic searching by titles using neoadjuvant treatments for PDAC will be performed in the annual meetings of European Society of Medical Oncology and American Society of Clinical Oncology (2018-2020).

CLINICALTRIALS

gov will also be searched for grey literature. Two reviewers will perform search strategies and extract data independently. R0 resection rate and local control rate are defined as primary outcomes. Secondary outcomes include overall survival, disease-free survival and acute and late grade 3 and grade 4 toxicities. For randomised control trials, the risk of bias will be assessed using the Cochrane Risk of Bias Tool, while the risk of bias for non-randomised, observational studies will be evaluated using the Risk Of Bias In Non-randomised Studies-of Interventions. The quality of evidence will be evaluated using the version of Cochrane tool and Grades of Recommendation, Assessment, Development and Evaluation. Subgroup analysis and sensitivity analysis will be conducted in the present NMA.

ETHICS AND DISSEMINATION

This study will synthesise the evidence regarding dose schedule of neoadjuvant radiotherapy in patients with BRPC and LAPC. We hope the findings from this NMA will help clinicians and patients select the optimal modality and dose schedule of neoadjuvant radiotherapy with respect to patient-reported outcomes. As no primary data collection will be undertaken, no ethics approval is required. The results will be disseminated through peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42020222408.

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.

Efficacy and safety of new anti-CD20 monoclonal antibodies versus rituximab for induction therapy of CD20+ B-cell non-Hodgkin lymphomas: a systematic review and meta-analysis

Rituximab combined with chemotherapy is the first-line induction therapy of CD20 positive B-cell non-Hodgkin lymphomas (CD20+ B-NHL). Recently new anti-CD20 monoclonal antibodies (mAbs) have been developed, but their efficacy and safety compared with rituximab are still controversial. We searched MEDLINE, Embase, and Cochrane Library for eligible randomized controlled trials (RCTs) that compared new anti-CD20 mAbs with rituximab in induction therapy of B-NHL. The primary outcomes are progression-free survival (PFS) and overall survival (OS), additional outcomes include event-free survival (EFS), disease-free survival (DFS), overall response rate (ORR), complete response rate (CRR) and incidences of adverse events (AEs). Time-to-event data were pooled as hazard ratios (HRs) using the generic inverse-variance method and dichotomous outcomes were pooled as odds ratios (ORs) using the Mantel-Haenszel method with their respective 95% confidence interval (CI). Eleven RCTs comprising 5261 patients with CD20+ B-NHL were included. Compared with rituximab, obinutuzumab significantly prolonged PFS (HR 0.84, 95% CI 0.73-0.96, P = 0.01), had no improvement on OS, ORR, and CRR, but increased the incidences of serious AEs (OR 1.29, 95% CI 1.13-1.48, P < 0.001). Ofatumumab was inferior to rituximab in consideration of ORR (OR 0.73, 95% CI 0.55-0.96, P = 0.02), and had no significant differences with rituximab in regard to PFS, OS and CRR. 131I-tositumomab yielded similar PFS, OS, ORR and CRR with rituximab. 90Y-ibritumomab tiuxetan increased ORR (OR 3.07, 95% CI 1.47-6.43, P = 0.003), but did not improve PFS, DFS, OS and CRR compared with rituximab. In conclusion, compared with rituximab in induction therapy of CD20+ B-NHL, obinutuzumab significantly improves PFS but with higher incidence of AEs, ofatumumab decreases ORR, 90Y-ibritumomab tiuxetan increases ORR.

Optimal dose-fractionation schedule of palliative radiotherapy for patients with bone metastases: a protocol for systematic review and network meta-analysis

INTRODUCTION

The optimal dose-fractionation schedule of palliative radiotherapy has been debated in patients with bone metastases. Our objective is to comprehensively compare multiple fraction schedules with single fraction radiotherapy in terms of efficacy and toxicities by performing a systematic review and network meta-analysis.

METHODS AND ANALYSIS

Electronic searches of titles/abstracts of palliative radiotherapy for bone metastases will be performed, using PubMed, Cochrane Library, Embase, clinical trials, American Society for Therapeutic Radiology and Oncology and European Society of Radiotherapy and Oncology. The primary outcome of interest is the incidence of skeletal-related event following palliative radiotherapy for bone metastases in prospective studies. The risk of bias and quality of evidence will be evaluated based on Cochrane Collaboration's tool and Grades of Recommendation, Assessment, Development and Evaluation in the network meta-analysis. We will conduct subgroup analysis and sensitivity analysis regardless of heterogeneity estimates.

ETHICS AND DISSEMINATION

This study will synthesise the evidence regarding dose-fractionation schedule of palliative radiotherapy in patients with bone metastases. We hope the findings from this study will help clinicians and patients select optimum palliative radiotherapy by identifying the optimal dose-fractionation schedule of palliative radiotherapy with the most value in terms of patient-important outcomes. The evidence obtained from network meta-analysis will help to guide head-to-head research in the future. The results will be disseminated through international conference reports and peer-reviewed manuscripts. Ethics review board is not required for this network meta-analysis.

PROSPERO REGISTRATION NUMBER

CRD42019135195.

High-dose Methotrexate plus temozolomide with or without rituximab in patients with untreated primary central nervous system lymphoma: A retrospective study from China

The purpose of this retrospective study was to compare the efficacy and toxicity of high-dose methotrexate plus temozolomide (MT regimen) and rituximab plus MT (RMT regimen) in patients with untreated primary central nervous system lymphoma (PCNSL). A total of 62 patients with untreated PCNSL were enrolled between January 2005 and December 2015, with the median age of 53.5 years (range 29-77).In this study, 32 patients received RMT as induction therapy, and 30 received MT. Objective responses were noted in 93.7% of the patients in the RMT group and in 69.0% of the patients in the MT group (P = 0.018), while complete responses were noted in 53.2% of the patients in the RMT group and 27.6% of the patients in the MT group (P < 0.001). The 2- and 5-year PFS rates were 81.3% and 53.3%, respectively, for the RMT group and 46.5% and 29.1%, respectively, for the MT group (P = 0.019). The 2- and 5-year overall survival (OS) rates were 82.3% and 82.3%, respectively, for the RMT group and 65.7% and 50.0%, respectively, for the MT group (P = 0.015). Multivariate analyses showed that therapeutic regimen (RMT vs MT) was an independent prognostic factor for PFS and OS. Our encouraging results suggest that the RMT regimen may be a feasible and safe therapeutic approach for first-line treatment of PCNSL.

Lentivirus-mediated down-regulation of CK2α inhibits proliferation and induces apoptosis of malignant lymphoma and leukemia cells

Casein kinase II subunit alpha (CK2α) is highly expressed in many malignant tumor tissues, including lymphomas and leukemia. To investigate the role of CK2α in cell proliferation and apoptosis of malignant lymphomas and leukemia, 2 lymphoma cell lines and one leukemia cell line were infected with CK2α shRNA lentivirus or negative control shRNA lentivirus, and stably infected cell lines were established. Real-time PCR and Western blot results showed that the mRNA and protein levels of CK2α were significantly reduced in CK2α knockdown cells. The tetrazolium-based colorimetric (MTT) assay found that down-regulation of CK2α inhibited the proliferation of these cells. Flow cytometry analysis showed that inhibition of CK2α induced cell cycle arrest and apoptosis of lymphoma and leukemia cells. In accordance with these, down-regulation of CK2α also reduced the protein levels of proliferating cell nuclear antigen (PCNA), cyclinD1, and bcl-2, and increased the protein expression of bax, cleaved caspase-3, cleaved caspase-9, and cleaved poly(ADP ribose) polymerase (PARP). Moreover, knockdown of CK2α impeded the growth of xenograft tumors in vivo. In summary, our study revealed that CK2α may contribute to the development of malignant lymphoma and leukemia, and serve as the therapeutic target of these malignant tumors.

TP53 hotspot mutations are predictive of survival in primary central nervous system lymphoma patients treated with combination chemotherapy

Primary central nervous system lymphoma (PCNSL) is an aggressive variant of diffuse large B-cell lymphoma (DLBCL) confined to the CNS. TP53 mutations (MUT-TP53) were investigated in the context of MIR34A/B/C- and DAPK promoter methylation status, and associated with clinical outcomes in PCNSL patients. In a total of 107 PCNSL patients clinical data were recorded, histopathology reassessed, and genetic and epigenetic aberrations of the p53-miR34-DAPK network studied. TP53 mutational status (exon 5-8), with structural classification of single nucleotide variations according to the IARC-TP53-Database, methylation status of MIR34A/B/C and DAPK, and p53-protein expression were assessed. The 57/107 (53.2 %) patients that were treated with combination chemotherapy +/- rituximab (CCT-treated) had a significantly better median overall survival (OS) (31.3 months) than patients treated with other regimens (high-dose methotrexate/whole brain radiation therapy, 6.0 months, or no therapy, 0.83 months), P < 0.0001. TP53 mutations were identified in 32/86 (37.2 %), among which 12 patients had hotspot/direct DNA contact mutations. CCT-treated patients with PCNSL harboring a hotspot/direct DNA contact MUT-TP53 (n = 9) had a significantly worse OS and progression free survival (PFS) compared to patients with non-hotspot/non-direct DNA contact MUT-TP53 or wild-type TP53 (median PFS 4.6 versus 18.2 or 45.7 months), P = 0.041 and P = 0.00076, respectively. Multivariate Cox regression analysis confirmed that hotspot/direct DNA contact MUT-TP53 was predictive of poor outcome in CCT-treated PCNSL patients, P = 0.012 and P = 0.008; HR: 1.86 and 1.95, for OS and PFS, respectively. MIR34A, MIR34B/C, and DAPK promoter methylation were detected in 53/93 (57.0 %), 80/84 (95.2 %), and 70/75 (93.3 %) of the PCNSL patients with no influence on survival. Combined MUT-TP53 and MIR34A methylation was associated with poor PFS (median 6.4 versus 38.0 months), P = 0.0070. This study suggests that disruption of the p53-pathway by MUT-TP53in hotspot/direct DNA contact codons is predictive of outcome in CCT-treated PCNSL patients, and concomitant MUT-TP53 and MIR34A methylation are associated with poor PFS.