Study Design.This was a retrospective study focusing on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess treatment response in patients with spinal metastases.Objective.To demonstrate DCE-MRI changes before and after radiation treatment and correlating with other imaging and clinical findings.Summary of Background Data.Currently, conventional imaging is limited in evaluating early treatment success or failure, which impacts patient care.Methods.Consecutive patients with known spinal metastases underwent DCE-MRI before and after radiotherapy. Perfusion data on 19 lesions were analyzed. Radiotherapy was classified as success (n = 17) or failure (n = 2) on the basis of evidence of tumor contraction (n = 4), negative positron emission tomography (n = 2), or stability for more than 11 months (n = 11). Perfusion parameters blood plasma volume (Vp), time-dependent leakage (Ktrans), area under the curve, and peak enhancement were derived from the signal intensity-time curves and changes in parameter values from pre- to post-treatment were calculated. Curve morphologies were also qualitatively assessed in 13 pre- and 13 post-treatment scans.Results.Vp was the strongest predictor of treatment response (false-positive rate = 9.38 × 10−9 and false-negative rate = 0.055). All successfully treated lesions showed decreases in Vp, and the 2 treatment failures showed drastic increases in Vp. Changes in area under the curve and peak enhancement demonstrated similar relationships to the observed treatment response, whereas changes in Ktrans showed no significant relationship. Signal intensity curve morphologies also demonstrated specificity for active disease (11 of 13) and treated disease (8 of 13).Conclusion.Changes in perfusion, particularly Vp, reflect tumor responses to radiotherapy in spinal bone metastases. These changes were able to predict positive outcomes earlier than 6 months after treatment in 16 of 17 tumors. The ability of DCE-MRI to detect early treatment response has the potential to improve patient care and outcome.

Objective: Stroke frequently complicates infective endocarditis (IE). However, the temporal relationship between these diseases is uncertain.Methods: We performed a retrospective study of adult patients hospitalized for IE between July 1, 2007, and June 30, 2011, at nonfederal acute care hospitals in California. Previously validated diagnosis codes were used to identify the primary composite outcome of ischemic or hemorrhagic stroke during discrete 1-month periods from 6 months before to 6 months after the diagnosis of IE. The odds of stroke in these periods were compared with the odds of stroke in the corresponding 1-month period 2 years earlier, which was considered the baseline risk of stroke.Results: Among 17,926 patients with IE, 2,275 strokes occurred within the 12-month period surrounding the diagnosis of IE. The risk of stroke was highest in the month after diagnosis of IE (1,640 vs 17 strokes in the corresponding month 2 years prior). This equaled an absolute risk increase of 9.1% (95% confidence interval 8.6%-9.5%) and an odds ratio of 96.5 (95% confidence interval 60.1-166.0). Stroke risk was significantly increased beginning 4 months before the diagnosis of IE and lasting 5 months afterward. Similar temporal patterns were seen when ischemic and hemorrhagic strokes were considered separately. Conclusions:The association between IE and stroke persists for longer than previously reported.Most diagnoses of stroke and IE are made close together in time, but a period of heightened stroke risk becomes apparent several months before the diagnosis of IE and lasts for several months afterward. Infective endocarditis (IE) occurs in 1.7 to 6.2 per 100,000 people per year in the United States and Europe.1 Stroke often complicates IE, affecting approximately 16% to 25% of patients with IE.2,3 Cerebral embolism heralding or following a diagnosis of IE substantially increases morbidity and mortality.3-5 However, knowledge is limited regarding the time period during which patients with IE face a heightened stroke risk, with reports ranging from as early as 40 days before IE is recognized to as late as 5 weeks after the start of antibiotic treatment.3,4,6-8 Recent data suggest that IE may increase stroke risk for even longer periods of time, as one European cohort study reported that patients had a moderately increased risk of embolic events up to 180 days after community-acquired bacteremia. 9 We hypothesized that the risk of stroke in the setting of IE persists for longer than current data suggest. Therefore, we sought to better delineate the time period during which patients diagnosed with IE face an increased stroke risk.METHODS Study design. We performed a retrospective study of the temporal relationship between IE and stroke diagnoses using administrative claims data from California. The California Office of Statewide Health Planning and Development collects data about all emergency department (ED) visits and hospital stays at nonfederal acute care hospitals in California. After quality checking, these...

A direct role for BK polyomavirus infection in malignant tumors of renal allografts and urinary tract is emerging. Case reports suggest a link between BK virus (BKV) reactivation and development of malignancy in renal allograft recipients. Herein we describe the first case of BKV positive invasive urothelial carcinoma within the renal allograft, presenting with chronic diarrhea and weight loss 5 years following resolution of BK viremia/nephropathy (BKVN). Unique to our case was the remote history of BK viremia/BKVN, rising titer of anti-HLA antibody and presence of renal limited urothelial carcinoma with microinvasion of malignant cells staining positive for SV40 large T antigen (T-Ag). These findings suggest that persistence of subclinical BKV infection within the renal allograft may play a role in the malignant transformation of epithelial cells. Patients with history of BKVN may be at risk for kidney and urinary tract malignancy despite resolution of BK viremia/BKVN.