Addition of high-dose methotrexate to standard treatment for patients with high-risk diffuse large B-cell lymphoma contributes to improved freedom from progression and survival but does not prevent central nervous system relapse

Efficacy of intravenous high-dose methotrexate in preventing relapse to the central nervous system in R-CHOP(-like)-treated, high-risk, diffuse large B-cell lymphoma patients and its effect on mortality: a systematic review and meta-analysis

Central nervous system (CNS) relapse in patients with diffuse large B-cell lymphoma (DLBCL) carries a dismal prognosis and most clinical guidelines recommend CNS prophylaxis to patients deemed at high risk of CNS relapse. However, results from observational studies investigating the effect of CNS prophylaxis have yielded conflicting results. The aims of this study were to evaluate: (i) whether addition of prophylactic intravenous high-dose methotrexate (HD-MTX) reduces the risk of CNS relapse in high-risk DLBCL patients treated with R-CHOP or similar, and (ii) whether HD-MTX prophylaxis confers an overall survival benefit, irrespective of CNS relapse. We performed a systematic search of MEDLINE/PubMed and EMBASE for data on DLBCL patients at high risk of CNS relapse treated with R-CHOP or similar who received HD-MTX as an intervention and a comparator arm of patients who did not receive prophylaxis and/or intrathecal prophylaxis. A risk of bias was estimated using the ROBINS-I tool and the quality of the evidence was assessed by the GRADE approach. Finally, a meta- analysis based on the systematic review was conducted. A total of 1,812 studies were screened. No randomized controlled trials were identified. Seven observational studies comprising 1,661 patients met the inclusion criteria. We found a statistically non-significant relative risk of 0.54 (95% confidence interval: 0.27-1.07) of CNS relapse for patients receiving HD-MTX versus controls. The meta-analysis investigating mortality demonstrated a relative risk of death of 0.70 (95% confidence interval: 0.44-1.11) for patients treated with HD-MTX versus controls. The overall risk of bias was adjudged as "serious" and the quality of the evidence was rated as "low". In conclusion, our data indicate that HD-MTX does not prevent or, at best, only slightly reduces the risk of CNS relapse and confers no survival benefit.

Central nervous system prophylaxis in large B-cell lymphoma: A British Society for Haematology Good Practice Paper

This Good Practice Paper provides recommendations for the baseline investigation, risk stratification and use of prophylactic interventions for patients with large B-cell lymphoma at risk of central nervous system relapse. Recent evidence which has questioned the role of high-dose methotrexate in this clinical scenario is discussed in detail.

Model for Predicting Central Nervous System Relapse in Diffuse Large B-Cell Lymphoma and Discussion of Prophylaxis Measures

OBJECTIVE

Relapse of the central nervous system (CNS) is a rare but fatal complication in diffuse large B-cell lymphoma (DLBCL). The purpose of this study is to learn how to identify high-risk patients and take effective preventive measures.

METHODS

We retrospectively analyzed 1,290 adult patients with DLBCL at Peking University Cancer Hospital and Shanxi Bethune Hospital between 2010 and 2020.

RESULTS

There were 55 patients with CNS relapse who had a median follow-up of 5 years. The risk of CNS relapse was 1.58% in the low-risk group, 5.66% in the moderate-risk group, and 11.67% in the high-risk group based on CNS International Prognostic Index (CNS-IPI). We found that CNS-IPI and testicular involvement were risk factors for CNS relapse, with OR 1.913 (95% CI: 1.036∼3.531; P = 0.038) versus. OR 3.526 (95% CI: 1.335∼9.313; P = 0.011), respectively. Intrathecal MTX and/or cytarabine prophylaxis was used in 166 patients (13.94%), intravenous (IV) high-dose methotrexate (HD-MTX) prophylaxis in 8 patients (0.67%), and intrathecal plus intravenous prophylaxis in 15 patients (1.26%). There was no significant difference in CNS relapse risk between IT, HD-MTX, and no prophylaxis recipients (12.7% vs. 0% vs. 23.6%, respectively, P = 0.170). The risk of CNS relapse was similar whether or not patients accepted prophylaxis (5-year risk 4.1% vs. 2.2%, P = 0.140).

CONCLUSIONS

Central nervous system (CNS) relapse is associated with high risk CNS-IPI and testicular involvement. Therefore, it is necessary to pursue novel prophylactic strategies for CNS relapse.

Central nervous system lymphomas-Assessment and treatment and prevention of central nervous system relapse

In this review focused on lymphoma and the central nervous system (CNS), we summarize recent developments in the management of primary (PCNSL) and secondary CNS lymphoma (SCNSL), treatment of CNS lymphoma in the older population, the neuroradiological assessment of CNS lymphoma and finally highlight the ongoing debate on optimal CNS prophylaxis. The section on PCNSL focuses on the different approaches available for frontline treatment in Europe and the United States and discusses consolidation strategies. We then highlight available strategies to treat PCNSL in the elderly population, an area of unmet need. New therapies aiming at minimizing toxicity and prioritizing quality of life are emerging for these patients. Secondary CNS lymphoma, especially in the relapsed/refractory setting is another area of unmet need, and the efficacy of CAR-T cell therapy is being explored. We provide an overview of the imaging challenges in the neuroradiological assessment of CNS lymphoma. Finally, the section on CNS prophylaxis summarizes recent findings from large retrospective studies challenging the efficacy of present approaches to prophylaxis in higher-risk patients with lymphoma.

Prevention and management of secondary central nervous system lymphoma

Secondary central nervous system (CNS) lymphoma (SCNSL) is defined by the involvement of the CNS, either at the time of initial diagnosis of systemic lymphoma or in the setting of relapse, and can be either isolated or with synchronous systemic disease. The risk of CNS involvement in patients with diffuse large B-cell lymphoma is approximately 5%; however, certain clinical and biological features have been associated with a risk of up to 15%. There has been growing interest in improving the definition of patients at increased risk of CNS relapse, as well as identifying effective prophylactic strategies to prevent it. SCNSL often occurs within months of the initial diagnosis of lymphoma, suggesting the presence of occult disease at diagnosis in many cases. The differing presentations of SCNSL create the therapeutic challenge of controlling both the systemic disease and the CNS disease, which uniquely requires agents that penetrate the blood-brain barrier. Outcomes are generally poor with a median overall survival of approximately 6 months in retrospective series, particularly in those patients presenting with SCNSL after prior therapy. Prospective studies of intensive chemotherapy regimens containing high-dose methotrexate, followed by hematopoietic stem cell transplantation have shown the most favorable outcomes, especially for patients receiving thiotepa-based conditioning regimens. However, a proportion of patients will not respond to induction therapies or will subsequently relapse, indicating the need for more effective treatment strategies. In this review we focus on the identification of high-risk patients, prophylactic strategies and recent treatment approaches for SCNSL. The incorporation of novel agents in immunochemotherapy deserves further study in prospective trials.

Clinical use of HD-MTX monotherapy in a rare case of refractory primary bone diffuse large B-cell lymphoma with long-term survival after local radiotherapy: A case report

Primary bone diffuse large B-cell lymphoma (PB-DLBCL) has been rarely reported because of its low incidence. The optimal treatment plan for patients with relapsed/refractory PB-DLBCL remains controversial. In this study, we present a case of a 57-year-old patient with refractory PB-DLBCL to better understand this disease. The patient developed lumbosacral/low extremity pain. A lumbar magnetic resonance imaging (MRI) revealed skeletal lesions with osteolysis in L4-L5 and S1. With the failure of multi-line chemotherapy, the patient developed paralysis of both lower limbs. 18-Fluorinefluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and MRI showed new lesions in the femoral head, cervical and thoracic vertebrae. We tried to treat the patient with adjuvant radiotherapy and 10 courses of high-dose methotrexate (HD-MTX)-based monotherapy, after which the patient was able to walk and achieved complete remission (CR). To the best of our knowledge, this is the first attempt to use local radiotherapy combined with an HD-MTX regimen successfully for the treatment of refractory PB-DLBCL.

CNS prophylaxis in aggressive B-cell lymphoma

The prevention of central nervous system (CNS) relapse in diffuse large B-cell lymphoma (DLBCL) continues to be one of the most contentious areas of lymphoma management. Outcomes for patients with secondary CNS lymphoma (SCNSL) have historically been very poor. However, in recent years improved responses have been reported with intensive immunochemotherapy approaches, and there is a growing interest in potential novel/cellular therapies. Traditional methods for selecting patients for CNS prophylaxis, including the CNS International Prognostic Index, are hampered by a lack of specificity, and there is accumulating evidence to question the efficacy of widely employed prophylactic interventions, including intrathecal and high-dose methotrexate (HD-MTX). Given the potential toxicity of HD-MTX in particular and the ongoing need to prioritize systemic disease control in high-risk patients, there is an urgent need to develop more robust methods for identifying patients at highest risk of CNS relapse, as well as investigating prophylactic interventions with greater efficacy. Here we review new evidence in this field from the last 5 years, focusing on the potential use of molecular diagnostics to improve the identification of high-risk patients, recent large data sets questioning the efficacy of HD-MTX, and the current approach to management of patients with SCNSL. We provide a suggested algorithm for approaching this very challenging clinical scenario.

The role of central nervous system (CNS) prophylaxis in preventing DLBCL patients from CNS relapse: A network meta-analysis

BACKGROUND

Secondary central nervous system (CNS) relapses are an uncommon yet devastating complication in diffuse large B cell lymphoma (DLBCL). Although several prophylaxis attempts were employed clinically in order to reduce the CNS relapse rate, the optimal management remained uncertain.

METHODS

We employed conventional meta-analysis along with Network meta-analysis to investigate an optimal prophylactic strategy. The primary outcome was CNS relapse rate.

RESULTS

A total of thirty-six studies comprising 5 RCTs, one clinical trial and 30 observational studies were included. Rituximab overall was superior in reducing CNS relapse rate, and the statistical significance exists (RR 0.79(0.68-0.93), p = 0.004). In rituximab era, none of intravenous, intrathecal administration or novel target agents could significantly decrease CNS relapse rate in high CNS risk patients. Intensive chemotherapy regimen containing HD-MTX with HD-Ara-C (SUCRA 93.4 %) was ranked as the first in reducing CNS relapse rate followed by no prophylaxis (SUCRA 57.5 %), HD-MTX (SUCRA 53.1 %), IT (SUCRA 34.5 %) and lenalidomide maintenance (SUCRA 11.5 %). In addition, intercalated HD-MTX had a trend of reducing CNS relapse but without statistical significance (RR 0.86(0.44-1.68), p = 0.67). However, i-HD-MTX was associated with increased grade 3-4 toxicities and prolonged inpatient stay. Early HD-MTX exposure also increased the treatment related death.

CONCLUSION

Our network meta-analysis provides an overview of the relative efficacy of all available CNS prophylaxis strategies in DLBCL. In rituximab era, none of intravenous, intrathecal administration or novel target agents could significantly decrease CNS relapse rate in high CNS risk patients. Further studies with prospective, randomized clinical trials as well as with more focus on novel target agents that could spread blood-brain barriers are suggested.

Predictive impact of soluble interleukin-2 receptor and number of extranodal sites for identification of patients at very high risk of CNS relapse in diffuse large B-cell lymphoma

There remains an unmet clinical need to identify which patients with diffuse large B-cell lymphoma (DLBCL) would benefit from central nervous system (CNS) prophylaxis, due to the low positive predictive value (PPV; 10%-15%) of the currently available predictive models. To stratify patients at high risk of developing CNS relapse, we retrospectively analyzed 182 patients with DLBCL initially treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), or a R-CHOP-like regimen. Among them, 17 patients relapsed with CNS involvement, and the 2-year rate of CNS relapse was 7.9%. Upon carrying out multivariate analysis, ≥3 extranodal sites and elevated soluble interleukin-2 receptor (sIL-2R) levels at diagnosis were identified as independent risk factors for CNS relapse. The 2-year and 3.5-year rates of CNS relapse were 57.1% and 78.6%, respectively, in patients with both elevated sIL-2R and ≥3 extranodal sites. Furthermore, combined use of these risk factors of both elevated sIL-2R and ≥3 extranodal sites resulted in a high PPV (71.4%), negative predictive value (93.1%), and overall accuracy (92.3%) for undergoing CNS relapse. In conclusion, we propose a simple and valuable tool to predict patients with DLBCL at very high risk of CNS relapse.

Feasibility of high-dose methotrexate administered on day 1 of (R)CHOP in aggressive non-Hodgkin lymphomas

The optimal timing for administering high-dose methotrexate (HDMTX) when combined with (R)CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone, with/without rituximab) is unclear. Recent data showed that the administration of prophylactic HDMTX before day 10 of R- CHOP may lead to fewer treatment delays. Herein, we report our experience with HDMTX administered on day 1 of (R)CHOP in patients with aggressive non-Hodgkin lymphoma (NHL). We identified 140 patients treated with ≥1 cycle of HDMTX combined with (R)CHOP for prophylaxis against (n = 84) or treatment of (n = 56) central nervous system (CNS) involvement. Overall, (R)CHOP treatment delays ≥7 days (4% of cycles, 13% of patients), doxorubicin, and/or cyclophosphamide dose reductions (1% of cycles, 6% of patients) or (R)CHOP discontinuations due to toxicity (4% of patients) were uncommon. Neutropenic fever (NF) occurred in 7% of cycles and 24% of patients and was more common during HDMTX-containing cycles. Acute kidney injury (AKI) occurred in 19% of cycles but was mostly grade ≤2. Grade ≥3 hepatotoxicity and mucositis were uncommon (each 2% of cycles). In the prophylaxis cohort, the rates of NF and grade ≥2 AKI were lower in patients who initiated HDMTX with cycle 2 or later (11% vs 30%, P = .03 and 16% vs 39%, P = .03, respectively). Our data show that HDMTX administration on day 1 of (R)CHOP may improve the deliverability of (R)CHOP and the overall safety of the regimen compared with historical data of HDMTX administration on day 10 or later of R-CHOP. Delaying prophylactic HDMTX beyond cycle 1 of (R)CHOP may reduce the risk of NF and AKI.

An Elusive Seizure

We present a case of a healthy 62-year-old woman who developed recurrent seizures preceded by subacute cognitive slowing, ataxia, night sweats, and weight loss. She was found to have cytopenias, multifocal T2/FLAIR hyperintensities on magnetic resonance imaging (MRI), and magnetic susceptibility artifact lesions on susceptibility weighted imaging (SWI). Her symptoms, imaging and laboratory abnormalities all improved with high-doses of steroids and intravenous immunoglobulin (IVIG). But recurred several weeks after completing treatment. Despite extensive work-up, she required multiple hospitalizations and repeat diagnostic studies to arrive at a diagnosis. With an expert discussant in hematology and oncology, we review the differential diagnosis and stepwise approach of unexplained neuro-inflammatory syndromes with cytopenias and systemic symptoms. Our case highlights how time, empiric treatment response, and repeated diagnostic studies refine differential diagnoses and subsequent evaluation. After revealing the diagnosis, we discuss the heterogenous clinical manifestations of this disease process.

Systemic vs. intrathecal central nervous system prophylaxis in primary adrenal/renal diffuse large b-cell LYMPHOMA: A multi-institution retrospective analysis and systematic review

Primary adrenal lymphoma (PAL) and primary renal lymphoma (PRL) are rare extranodal lymphomas, predominantly of diffuse large B-cell lymphoma subtype. Primary adrenal and renal lymphomas (PARL) exhibit a high predilection for the central nervous system (CNS). Therefore, current guidelines support the use of CNS prophylaxis in PARL, particularly in cases of high-risk Central Nervous System International Prognostic Index (CNS-IPI). However, the route of administration (i.e. systemic vs. intrathecal chemotherapy) has not been clearly elucidated. With this in mind, we initiated an international collaboration and literature review to analyze 50 patient cases, 20 of which received CNS prophylaxis. Based on our analysis, we conclude that PARL may indicate a need for CNS chemo-prophylaxis in the form of systemic high-dose methotrexate (HD-MTX) over intrathecal methotrexate (IT-MTX), although IT-MTX may still have utility in certain cases.

High-dose methotrexate is effective for prevention of isolated CNS relapse in diffuse large B cell lymphoma

The role of central nervous system (CNS) prophylaxis with high-dose methotrexate (HDMTX) in DLBCL is controversial. In this retrospective study, we evaluated the efficacy of prophylactic HDMTX on isolated CNS relapse, concomitant CNS and systemic relapse, systemic relapse, and survival outcomes in 226 patients with newly diagnosed DLBCL and high-risk CNS International Prognostic Index (CNS-IPI) score treated with RCHOP. The three-year risk of isolated CNS relapse was significantly lower in patients who received HDMTX, at 3.1% compared to 14.6% (P = 0.032) in those who did not. However, neither concomitant CNS-systemic relapse rates, systemic relapse rates, nor three-year PFS and OS were significantly different between treatment groups in multivariable analysis. Among propensity score-matched patients (N = 102), HDMTX was also associated with significantly lower isolated CNS relapse rates (HR 0.06, 95% CI 0.004–0.946, P = 0.046). HDMTX was well tolerated with manageable toxicities when given at a dose of 3 g/m² by day 3 of RCHOP chemotherapy. Using propensity score matching and multivariable regression to yield treatment groups with well-balanced covariates, we showed that prophylactic HDMTX improved isolated CNS relapse rates but did not decrease concomitant CNS-systemic relapse rates, systemic relapse rates, or improve survival outcomes.

Ineffectiveness of high-dose methotrexate for prevention of CNS relapse in diffuse large B-cell lymphoma

Central nervous system (CNS) relapse affects 5% of diffuse large B-cell lymphoma (DLBCL) patients and portends a poor prognosis. Prophylactic intravenous high-dose methotrexate (HD-MTX) is frequently employed to reduce this risk, but there is limited evidence supporting this practice. We conducted a multicenter retrospective study to determine the CNS relapse risk with HD-MTX in DLBCL patients aged 18-70 years treated in Alberta, Canada between 2012 and 2019. Provincial guidelines recommended HD-MTX for patients at high-risk of CNS relapse based upon CNS-IPI score, double-hit lymphoma, or testicular involvement. Among 906 patients with median follow-up 35.3 months (range 0.29-105.7), CNS relapse occurred in 1.9% with CNS-IPI 0-1, 4.9% with CNS-IPI 2-3, and 12.2% with CNS-IPI 4-6 (p < .001). HD-MTX was administered to 115/326 (35.3%) high-risk patients, of whom 96 (83.5%) had CNS-IPI score 4-6, 45 (39.1%) had double-hit lymphoma, and four (3.5%) had testicular lymphoma. The median number of HD-MTX doses was two (range 1-3). Central nervous system relapse risk was similar with versus without HD-MTX (11.2% vs. 12.2%, p = .82) and comparable to previous reports of high-risk patients who did not receive CNS prophylaxis (10-12%). In multivariate and propensity score analyses, HD-MTX demonstrated no association with CNS relapse, progression-free survival, or overall survival. This study did not demonstrate a benefit of prophylactic HD-MTX in this high-risk patient population. Further study is required to determine the optimal strategy to prevent CNS relapse in DLBCL.

Prophylaxis with intrathecal or high-dose methotrexate in diffuse large B-cell lymphoma and high risk of CNS relapse

Although methotrexate (MTX) is the most widely used therapy for central nervous system (CNS) prophylaxis in patients with diffuse large B-cell lymphoma (DLBCL), the optimal regimen remains unclear. We examined the efficacy of different prophylactic regimens in 585 patients with newly diagnosed DLBCL and high-risk for CNS relapse, treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or R-CHOP-like regimens from 2001 to 2017, of whom 295 (50%) received prophylaxis. Intrathecal (IT) MTX was given to 253 (86%) and high-dose MTX (HD-MTX) to 42 (14%). After a median follow-up of 6.8 years, 36 of 585 patients relapsed in the CNS, of whom 14 had received prophylaxis. The CNS relapse risk at 1 year was lower for patients who received prophylaxis than patients who did not: 2% vs. 7.1%. However, the difference became less significant over time (5-year risk 5.6% vs. 7.5%), indicating prophylaxis tended to delay CNS relapse rather than prevent it. Furthermore, the CNS relapse risk was similar in patients who received IT and HD-MTX (5-year risk 5.6% vs. 5.2%). Collectively, our data indicate the benefit of MTX for CNS prophylaxis is transient, highlighting the need for more effective prophylactic regimens. In addition, our results failed to demonstrate a clinical advantage for the HD-MTX regimen.

Impact of High-Dose Methotrexate on the Outcome of Patients with Diffuse Large B-Cell Lymphoma and Skeletal Involvement

Diffuse large B-cell lymphoma (DLBCL) with extra nodal skeletal involvement is rare. It is currently unclear whether these lymphomas should be treated in the same manner as those without skeletal involvement. We retrospectively analyzed the impact of combining high-dose methotrexate (HD-MTX) with an anthracycline-based regimen and rituximab as first-line treatment in a cohort of 93 patients with DLBCL and skeletal involvement with long follow-up. Fifty patients (54%) received upfront HD-MTX for prophylaxis of CNS recurrence (high IPI score and/or epidural involvement) or because of skeletal involvement. After adjusting for age, ECOG, high LDH levels, and type of skeletal involvement, HD-MTX was associated with an improved PFS and OS (HR: 0.2, 95% CI: 0.1-0.3, p < 0.001 and HR: 0.1, 95% CI: 0.04-0.3, p < 0.001, respectively). Patients who received HD-MTX had significantly better 5-year PFS and OS (77% vs. 39%, p <0.001 and 83 vs. 58%, p < 0.001). Radiotherapy was associated with an improved 5-year PFS (74 vs. 48%, p = 0.02), whereas 5-year OS was not significantly different (79% vs. 66%, p = 0.09). A landmark analysis showed that autologous stem cell transplantation was not associated with improved PFS or OS. The combination of high-dose methotrexate and an anthracycline-based immunochemotherapy is associated with an improved outcome in patients with DLBCL and skeletal involvement and should be confirmed in prospective trials.

Efficacy and safety of prophylactic high-dose MTX in high-risk DLBCL: a treatment intent-based analysis

Despite central nervous system (CNS) relapse occurring in >10% of high-risk diffuse large B-cell lymphoma (DLBCL) patients, the role of CNS-directed prophylaxis is controversial in the absence of randomized controlled trials. In this retrospective study, we aimed to evaluate the safety and efficacy of prophylactic high-dose methotrexate (HD-MTX) on CNS relapse and survival outcomes in 258 newly diagnosed R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone)-treated high-risk DLBCL patients, based on the initial treatment intent (ITT) of the physician on the use of prophylactic HD-MTX. Patients were classified into an ITT HD-MTX group (n = 128) and a non-ITT HD-MTX group (n = 130). The CNS relapse rate was not significantly different between these groups, with 2-year CNS relapse rates of 12.4% and 13.9%, respectively (P = 0.96). Three-year progression-free survival and overall survival rates in the ITT HD-MTX and non-ITT HD-MTX groups were 62.4% vs 64.5% (P = 0.94) and 71.7% vs 71.4% (P = 0.7), respectively. Also, propensity score-matched analyses showed no significant differences in the time-to-CNS-relapse, progression-free survival, or overall survival. The ITT HD-MTX group showed a higher incidence of grade ≥ 3 oral mucositis and elevated alanine aminotransferase. Prophylactic HD-MTX does not improve CNS relapse rate or survival outcomes in high-risk DLBCL patients, and it is accompanied by increased toxicities.

Patients with high-risk DLBCL benefit from dose-dense immunochemotherapy combined with early systemic CNS prophylaxis

Survival of patients with high-risk diffuse large B-cell lymphoma (DLBCL) is suboptimal, and the risk of central nervous system (CNS) progression is relatively high. We conducted a phase 2 trial in 139 patients aged 18 to 64 years who had primary DLBCL with an age-adjusted International Prognostic Index (aaIPI) score of 2 to 3 or site-specific risk factors for CNS recurrence. The goal was to assess whether a dose-dense immunochemotherapy with early systemic CNS prophylaxis improves the outcome and reduces the incidence of CNS events. Treatment consisted of 2 courses of high-dose methotrexate in combination with biweekly rituximab (R), cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP-14), followed by 4 courses of R-CHOP-14 with etoposide (R-CHOEP) and 1 course of high-dose cytarabine with R. In addition, liposomal cytarabine was administered intrathecally at courses 1, 3, and 5. Coprimary endpoints were failure-free survival and CNS progression rates. Thirty-six (26%) patients experienced treatment failure. Progression occurred in 23 (16%) patients, including three (2.2%) CNS events. At 5 years of median follow-up, failure-free survival, overall survival, and CNS progression rates were 74%, 83%, and 2.3%, respectively. Treatment reduced the risk of progression compared with our previous trial, in which systemic CNS prophylaxis was given after 6 courses of biweekly R-CHOEP (hazard ratio, 0.49; 95% CI, 0.31-0.77; P = .002) and overcame the adverse impact of an aaIPI score of 3 on survival. In addition, outcome of the patients with BCL2/MYC double-hit lymphomas was comparable to the patients without the rearrangements. The results are encouraging, with a low toxic death rate, low number of CNS events, and favorable survival rates. This trial was registered at www.clinicaltrials.gov as #NCT01325194.

Evaluation of cerebrospinal clonal gene rearrangement in newly diagnosed non-Hodgkin's lymphoma patients

Overt central nervous system (CNS) involvement in aggressive non-Hodgkin's lymphoma (NHL) is rare at diagnosis. Much effort is put to identify risk factors for occult CNS involvement, and the risk assessment of CNS relapse. Prophylactic treatment carries risk of adverse events and its efficacy is not clear. Detection of cerebrospinal fluid molecular gene rearrangement (GRR) as a method to detect occult disease has been studied in acute leukemia and primary CNS lymphoma. To date, the capacity of a positive GRR in newly diagnosed NHL patients to predict CNS relapse has not been addressed. We retrospectively studied the prognostic value of GRR in cerebrospinal fluid samples of 148 newly diagnosed patients with high grade NHL. We demonstrate that positive GRR at diagnosis does not affect PFS or OS and did not predict CNS relapse. However, although numbers were small, repeated positive samples (≥ 2) correlated with a higher risk for CNS relapse (p = 0.048), possibly stressing the need for an aggressive preventive approach.

Systemic HD-MTX for CNS prophylaxis in high-risk DLBCL patients: a prospectively collected, single-center cohort analysis

We evaluated the efficacy of systemic high-dose methotrexate (HD-MTX) for CNS prophylaxis in a prospectively recruited cohort of DLBCL patients at high risk of CNS relapse. High-risk CNS relapse was defined as the involvement of ≥ 2 extranodal sites with elevated lactate dehydrogenase (LDH); CNS international prognostic index (CNS-IPI) ≥ 4; or involvement of high-risk extranodal sites, including bone marrow, breasts, testes, and paranasal sinuses. Overall, 130 patients who received at least two cycles of standard chemoimmunotherapy were evaluated; of these, 64 patients received additional systemic HD-MTX, either on day 15 of alternating cycles or 2-5 weeks after completion of primary therapy. Patients receiving HD-MTX showed a generally higher risk of CNS relapse than the other 66 patients not receiving prophylaxis. The estimated 2-year cumulative CNS relapse, progression-free survival and overall survival rates were 8.1%, 66.3%, and 77.5%, respectively, in patients who received systemic HD-MTX and 6.9%, 67.4%, and 71.4%, respectively, in patients without prophylaxis, with no significant between-group differences. Although this study does not show that systemic HD-MTX is definitively effective, these results may be of help to other researchers investigating the utility of HD-MTX prophylaxis in mitigating negative risk factors.