Illerhaus, Gerald

Abstract Advanced molecular and pathophysiologic characterization of primary central nervous system lymphoma (PCNSL) has revealed insights into promising targeted therapeutic approaches. Medical imaging plays a fundamental role in PCNSL diagnosis, staging, and response assessment. Institutional imaging variation and inconsistent clinical trial reporting diminishes the reliability and reproducibility of clinical response assessment. In this context, we aimed to: (1) critically review the use of advanced positron emission tomography (PET) and magnetic resonance imaging (MRI) in the setting of PCNSL; (2) provide results from an international survey of clinical sites describing the current practices for routine and advanced imaging, and (3) provide biologically based recommendations from the International PCNSL Collaborative Group (IPCG) on adaptation of standardized imaging practices. The IPCG provides PET and MRI consensus recommendations built upon previous recommendations for standardized brain tumor imaging protocols (BTIP) in primary and metastatic disease. A biologically integrated approach is provided to addresses the unique challenges associated with the imaging assessment of PCNSL. Detailed imaging parameters facilitate the adoption of these recommendations by researchers and clinicians. To enhance clinical feasibility, we have developed both “ideal” and “minimum standard” protocols at 3T and 1.5T MR systems that will facilitate widespread adoption.

Abstract Background: Isolated brain parenchyma relapse as initial site of relapse is a rare complication of NHL and carries a poor prognosis. Few large series focus on treatment characteristics and outcomes of isolated brain parenchyma relapse of NHL. Methods: The IPCG conducted a retrospective review of patient and treatment characteristics and outcomes of this complication. Following initial diagnosis and treatment of NHL (1980–2004), cases with brain parenchyma relapse as initial relapse site, with no evidence of lymphoma elsewhere in the body at the time of brain relapse, were eligible. Cases with brain, spine or leptomeningeal involvement at NHL diagnosis were not eligible. Results: 113 cases were assembled from 13 investigators in 8 countries. Preliminary data summaries are: 94 (83%) cases had diffuse large B-cell NHL, 5 (4%) follicular lymphoma, 3 (3%) Burkitt’s lymphoma, other NHL subtypes (11) . Median age at NHL diagnosis was 61yrs (16–85 yrs). 55% were male. Median ECOG at NHL diagnosis was 1. Median time from NHL diagnosis to isolated brain relapse was 1.8 yrs (3 months–15.9 yrs). 76 (67%) relapsed in brain less than 3 yrs after NHL diagnosis. Symptoms at brain relapse included mental status changes in 37%, gait/balance disturbance (27%), motor/sensory symptoms (23%). Median ECOG at brain relapse was 2. Parenchyma relapse was documented by brain imaging plus biopsy in 54 (48%), or imaging without biopsy in 58 (52%); not reported (1). 53 (48%) cases had one brain lesion; 56 (50%) had two or more lesions; not reported (4). Site of relapse was cerebral hemispheres in 53 (48%) cases, deep brain structures (brain stem/cerebellum) in 30 (27%), cerebral hemispheres and deep brain structures in 23 (21%); not reported (7). At brain relapse, CSF was positive in 11 (10%) cases, negative in 56 (50%); not reported (46[40%]). Treatment for brain relapse was chemotherapy alone in 52 (46%) cases, WBRT alone in 34 (30%), chemotherapy followed by RT in 26 (23%), and brain surgery alone (1). 78 (69%) cases are deceased. Median survival from brain parenchyma relapse to death was 1.6 yrs (95% CI: 11 months–2.6 yrs). Effect of treatment type at brain relapse on survival, will be reported. Brain lymphoma was the cause of death in 49 (63%) cases; CNS toxicity was the cause in 6 (8%) cases. Conclusion: Though a rare relapse site, prospective studies are needed to improve understanding and outcomes of isolated brain parenchyma relapse of NHL.

Abstract Abstract 3655 Background Primary central nervous system lymphoma (PCNSL) is an aggressive lymphoma with devastating prognosis. High-dose methotrexate (HD-MTX) in combination with HD-cytarabine builds the backbone of current treatments. Elderly patients constitute 45% of cases, exhibit poor outcome and frequent iatrogenic toxicity. However, research efforts to optimize therapy in this subgroup have been neglected. On this background, we conducted a systematic review (SR) and individual patient data meta-analysis (IPDMA) to provide comprehensive evidence-based management strategy for elderly patients with PCNSL. Patients and Methods SR: We searched MEDLINE and EMBASE without language restriction. Eligibility criteria were prospective/retrospective observational studies or randomized trials (RCT) (all N>=10) that exclusively focused on first-line therapy/outcomes in immunocompetent PCNSL patients ≥60 years. Eligible studies were evaluated for methodological quality and reporting of the following baseline characteristics: Age, performance status (PS), involvement of deep brain structures (IDB), serum LDH at baseline, cerebro-spinal fluid (CSF) protein concentration elevation, neurotoxicity (as reported), specific co-morbidity indices, and functional status. For the IPDMA, investigators of eligible studies were asked to provide individual patient data. Minimal eligibility criteria: Age at baseline, details about first-line therapy, and follow-up information. If no data were available, studies were included in the SR, but not in the IPDMA. To maximize statistical power and generalizability, published/unpublished data from other international collaborators were included. Impact of different first-line treatments on overall survival (OS) was investigated using time dependent mixed effects multivariable Cox regression models (age and PS as fixed effects, study/database as random effect). Results SR: We identified 13 eligible studies including 583 patients in total, median age 68–76, published from 1996–2011. Design of studies: prospective (3 multicenter [1 RCT]; 2 single center), retrospective (4 multicenter and single-center, respectively). Accrual of the RCT was recently finished, but publication is pending. From published studies, information about age and therapy was given throughout, for clinical performance in 77%, for LDH and CSF protein in 15%, and IDB in 38%. Functional status was reported in only one study. From the identified 13 studies, 261 individual patient data were available for our IPDMA and pooled with 408 patients from other databases; altogether 669 patients diagnosed from 1977–2011. Preliminary results IPDMA: 50% were male, median age 68 (60–70 [N=431], 70–80 [N=211], >80 [N=22]); median KPS was 60% (10–100%). Therapy regimens widely varied. Overall response to first-line treatment was 65% (45% CR, 19% PR). After a median follow-up of 23 months (1–171), 44% were still alive, with a 3-year OS of 32% [95%CI, 29–37%]. Grouping by time of diagnosis revealed improvement for patients diagnosed after 1997 (N=462) (P<0.001). In multivariate analysis, MTX-based poly-chemotherapy (CT) (N=474) was associated with improved OS (Hazard ratio [HR] 0.69, 95% CI 0.52–0.91) compared to non-MTX regimens (N=195); this was consistent among patients who received consolidating WBRT (HR 0.33, 95% CI 0.01–0.66) and those who did not (HR 0.46, 95% CI 0.23–0.89). In patients who received any MTX-based poly-CT, addition of CHOP-like components (N=90) was not associated with improved OS (HR 0.98, 95% 0.65–1.48). Although any WBRT showed an overall trend for superior OS, it was associated with a 4-fold risk increase for neurotoxicity (Odds Ratio 4.21, 95% CI 2.23–8.21). Further results of treatment patterns and explorative comparisons will be presented at the meeting. Conclusion This international meta-analysis revealed widely varying treatment approaches and demonstrates that prognosis for elderly PCNSL patients is still poor. However, improvement over the last decades was observed. MTX-based poly-CT was associated with better outcome compared to non-MTX containing approaches. The addition of CHOP-like regimens to HD-MTX did not improve outcome. WBRT was associated with better outcome, but also clearly increased risk of neurotoxicity. Prospective trials designed ad hoc for elderly PCNSL patients are promptly needed. Disclosures: No relevant conflicts of interest to declare.

Abstract Isolated central nervous system (CNS) relapse involving the brain parenchyma is a rare complication of systemic non-Hodgkin lymphoma. We retrospectively analyzed patient characteristics, management, and outcomes of this complication. After complete response to initial non-Hodgkin lymphoma treatment, patients with isolated CNS relapse with the brain parenchyma as initial relapse site were eligible. Patients with isolated CNS relapse involving only the cerebrospinal fluid were not eligible. Information on 113 patients was assembled from 13 investigators; 94 (83%) had diffuse large B-cell lymphoma. Median time to brain relapse was 1.8 years (range, 0.25-15.9 years). Brain relapse was identified by neuroimaging in all patients; in 54 (48%), diagnostic brain tumor specimen was obtained. Median overall survival from date of brain relapse was 1.6 years (95% confidence interval, 0.9-2.6 years); 26 (23%) have survived 3 years or more. Median time to progression was 1.0 year (95% confidence interval, 0.7-1.7 years). Age less than 60 years (P = .006) at relapse and methotrexate use (P = .008) as front-line treatment for brain relapse were significantly associated with longer survival in a multivariate model. Our results suggest systemic methotrexate is the optimal treatment for isolated CNS relapse involving the brain parenchyma. Long-term survival is possible in some patients.