Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: Context: del(17p), del(11q), and associated p53 dysfunction predict for short survival and chemoresistance in B-cell chronic lymphocytic leukemia (CLL). DNA-dependent protein kinase (DNA-PK) is activated by DNA damage and mediates DNA double-strand break repair. We hypothesized that inhibiting DNA-PK would sensitize CLL cells to drug-induced DNA damage and that this approach could increase the therapeutic index of agents used to treat CLL.', 'Fifty-four CLL cases were characterized for poor prognosis markers [del(17p), del(11q), CD38, and ZAP-70]. In selected cases, DNA-PK catalytic subunit (DNA-PKcs) expression and activity and p53 function were also measured. Ex vivo viability assays established sensitivity to fludarabine and chlorambucil and also tested the ability of a novel DNA-PK inhibitor (NU7441) to sensitize CLL cells to these drugs. The effects of NU7441 on fludarabine-induced DNA damage repair were also assessed (Comet assays and detection of gammaH2AX).', 'DNA-PKcs levels correlated with DNA-PK activity and varied 50-fold between cases but were consistently higher in del(17p) (P = 0.01) and del(11q) cases. NU7441 sensitized CLL cells to chlorambucil and fludarabine, including cases with del(17p), del(11q), p53 dysfunction, or high levels of DNA-PKcs. NU7441 increased fludarabine-induced double-strand breaks and abrogated drug-induced autophosphorylation of DNA-PKcs at Ser2056. High DNA-PK levels predicted for reduced treatment-free interval.
Answer: These data validate the concept of targeting DNA-PKcs in poor risk CLL, and demonstrate a mechanistic rationale for use of a DNA-PK inhibitor. The novel observation that DNA-PKcs is overexpressed in del(17p) and del(11q) cases indicates that DNA-PK may contribute to disease progression in CLL.

A: Is dNA-dependent protein kinase a therapeutic target and an indicator of poor prognosis in B-cell chronic lymphocytic leukemia?
****
Q: Context: Multiple population-based studies have suggested increasing omission of radiation therapy in favor of alternative treatment strategies in lymphomas, with an associated negative impact on survival. Radiation therapy has long been considered the standard management for many mucosa-associated lymphoid tissue lymphomas. Thus, we aimed to evaluate patterns of treatment utilization and survival.', 'A retrospective analysis based on the National Cancer Database was performed on 22,378 patients with splenic, nodal, or extranodal stage I-II marginal zone lymphoma diagnosed between 1998 and 2012. A logistic regression model was used to assess the association between sociodemographic, tumor, and treatment characteristics and the utilization of radiation therapy. Multivariate propensity score-adjusted Cox proportional hazards models were performed to identify factors independently associated with overall survival (OS).', 'Of 22,378 patients, 82% had stage I disease, 77% had extranodal mucosa-associated lymphoid tissue lymphoma, 5% had splenic marginal zone lymphoma, and 64% were older than 60 years. Radiation therapy utilization decreased from a peak of 39% in 2007 to 33% in 2011 (P < .001), with a corresponding significant increase in systemic therapy utilization. Radiation therapy was associated with a 5- and 10-year OS of 86.7% and 68.8% compared with 78.3% and 54.3% for no radiation therapy (P < .001). On multivariate propensity score-adjusted survival analysis, radiation therapy remained independently associated with improved OS (hazard of death, 0.75; 95% confidence interval, 0.65-0.85; P < .001).
Answer: Although clinical guidelines endorse radiation therapy as the preferred initial therapy for early-stage nongastric and Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma, radiation therapy is underused. Radiation therapy with or without systemic therapy was associated with a significant improvement in OS and should remain standard of care.

A: Does underutilization of radiation therapy in early-stage marginal zone lymphoma negatively impact overall survival?
****
Q: Context: Thrombotic thrombocytopenic purpura (TTP) is a rare hematologic disorder that frequently presents with neurologic involvement. However, the yield and prognostic value of acute brain neuroimaging in patients with TTP has not been studied. Our aim was to evaluate brain imaging findings in consecutive patients with TTP and assess their impact on prognosis.', 'We retrospectively collected clinical, laboratory, and neuroradiologic information in 47 episodes of acute TTP studied with brain imaging at our medical center between 1997 and 2007. Head CT and brain MRI were evaluated independently by 2 investigators. We then performed statistical analysis to determine whether the presence of acute lesions on brain imaging was associated with worse functional outcome as assessed by the modified Rankin score upon discharge and long-term follow-up.', 'Ten patients (25%) of those who had a head CT had acute changes, half of them indicating posterior reversible encephalopathy syndrome (PRES). Most cases studied with brain MRI had acute changes (82%). More than half of those had evidence of PRES (48%). Atypical variants of PRES were seen in 2 patients with isolated basal ganglia involvement. Acute ischemia and hemorrhage were uncommon. Most patients with acute changes on brain imaging recovered favorably, and radiologic lesions were not associated with worse functional outcome.
Answer: Posterior reversible encephalopathy syndrome is the most common brain imaging abnormality in severe manifestations of thrombotic thrombocytopenic purpura. Large infarctions and hemorrhage are infrequent. Consequently, abnormal brain neuroimaging does not seem to impact patient outcome, and full neurologic recovery is possible even in comatose patients with extensive brain abnormalities on MRI.

A:
Are brain lesions most often reversible in acute thrombotic thrombocytopenic purpura?
****