Key Points• CXCL13 and CXCL12 mediate chemotaxis of CNS lymphoma cells, and CXCL13 concentration in CSF is prognostic.• CXCL13 plus IL-10 is highly specific for the diagnosis of CNS lymphoma.Establishing the diagnosis of focal brain lesions in patients with unexplained neurologic symptoms represents a challenge. The goal of this study is to provide evidence supporting functional roles for CXC chemokine ligand (CXCL)13 and interleukin (IL)-10 in central nervous system (CNS) lymphomas and to evaluate the utility of each as prognostic and diagnostic biomarkers. We demonstrate for the first time that elevated CXCL13 concentration in cerebrospinal fluid (CSF) is prognostic and that CXCL13 and CXCL12 mediate chemotaxis of lymphoma cells isolated from CNS lymphoma lesions. Expression of the activated form of Janus kinase 1 supported a role for IL-10 in prosurvival signaling. We determined the concentration of CXCL13 and IL-10 in CSF of CNS lymphoma patients and control cohorts including inflammatory and degenerative neurologic disease in a multicenter study involving 220 patients. Bivariate elevated CXCL13 plus IL-10 was 99.3% specific for primary and secondary CNS lymphoma, with sensitivity significantly greater than reference standard CSF tests. These results identify CXCL13 and IL-10 as potentially important biomarkers of CNS lymphoma that merit further evaluation and support incorporation of CXCL13 and IL-10 into diagnostic algorithms for the workup of focal brain lesions in which lymphoma is a consideration. (Blood. 2013;121(23):4740-4748) IntroductionDetermination of the pathological basis of focal brain lesions in patients with unexplained neurologic symptoms is a major clinical challenge. Persistent symptoms or rapid neurologic decline often mandates stereotactic brain biopsy, a highly invasive procedure with a 10% to 35% rate of diagnostic failure.1-3 Moreover, many lesions are not amenable to biopsy because of small size, location in deep brain structures, risk of hemorrhage, and other comorbidities.The diagnosis of central nervous system (CNS) involvement of non-Hodgkin lymphoma is a particular challenge because of lesional response to glucocorticoids and features on magnetic resonance imaging (MRI) that are shared with other pathologies including astrocytic neoplasms, demyelination, neurosarcoid, vasculitis, infections, and leptomeningeal dissemination of systemic cancer. Although flowcytometric and cytological analysis of cerebrospinal fluid (CSF) is useful in the evaluation of leptomeningeal disease, these tests are usually insensitive to pathological processes based in deep brain structures and rarely provide information that eliminates the need for brain biopsy; the sensitivity of CSF cytological analysis in the evaluation of primary CNS lymphoma (PCNSL) is ;15%. 4Advances that facilitate diagnosis and early treatment of CNS lymphoma would likely be cost-effective, minimize repeat diagnostic CSF and MRI evaluations and brain biopsies, and also lead to improved outcomes. [5][6][7] The molecular const...

BACKGROUND AND PURPOSE There is evidence that increased tumor cellular density within diagnostic specimens of primary central nervous system lymphoma (PCNSL) may have significant prognostic implications. Because cellular density may influence measurements of apparent diffusion coefficient (ADC) by using diffusion-weighted MR imaging (DWI), we hypothesized that ADC measured from contrast-enhancing regions might correlate with clinical outcome in patients with PCNSL. MATERIALS AND METHODS PCNSL tumors from 18 immunocompetent patients, treated uniformly with methotrexate-based chemotherapy, were studied with pretherapeutic DWI. Enhancing lesions were diagnosed by pathologic analysis as high-grade B-cell lymphomas. Regions of interest were placed around all enhancing lesions allowing calculation of mean, 25th percentile (ADC25%), and minimum ADC values. Histopathologic tumor cellularity was quantitatively measured in all patients. High and low ADC groups were stratified by the median ADC value of the cohort. The Welch t test assessed differences between groups. The Pearson correlation examined relationships between ADC measurements and tumor cellular density. Single and multivariable survival analysis was performed. RESULTS We detected significant intra- and intertumor heterogeneity in ADC measurements. An inverse correlation between cellular density and ADC measurements was observed (P < .05). ADC25% measurements less than the median value of 692 (low ADC group) were associated with significantly shorter progression-free and overall survival. Patients with improved clinical outcome were noted to exhibit a significant decrease in ADC measurements following high-dose methotrexate chemotherapy. CONCLUSIONS Our study provides evidence that ADC measurements within contrast-enhancing regions of PCNSL tumors may provide noninvasive insight into clinical outcome.

These findings indicate that breast stroma tissue outside the incident tumor can be quantified using signal enhancement ratio analysis on dynamic contrast-enhanced MRI. Stromal signal enhancement ratio is a potential indicator for response to treatment and for overall outcome in patients with breast cancer; however, these results should be validated in a prospective study.

Nineteen patients infected with human immunodeficiency virus (HIV) with varying levels of viral suppression achieved with antiretroviral therapy were evaluated to determine whether trivalent influenza vaccine activated HIV replication. Humoral immune responses and CD4+ lymphocyte subsets were compared in 5 HIV-uninfected vaccinated subjects. Transient elevations of plasma HIV RNA levels (76-89 copies/mL) appeared within 2 weeks in 3 of 11 patients with <50 copies/mL at baseline. Sustained elevation in HIV plasma RNA was observed in 7 of 8 patients with baseline HIV RNA of >50 copies/mL. HIV DNA decreased in patients with <400 RNA copies/mL at baseline and showed an HIV RNA increase after vaccination (n=8) when compared with 8 patients with <50 copies/mL at baseline who lacked viral response to vaccination. Concurrent decreases in proviral DNA and memory phenotype CD4+ cells in association with increased plasma HIV RNA after vaccination in patients with <400 RNA copies/mL at baseline suggest that in vivo mobilization of the latently infected cell reservoir may occur during potent antiretroviral therapy.