MRI radiomics in the prediction of the volumetric response in meningiomas after gamma knife radiosurgery.

PURPOSE: This report presents the first investigation of the radiomics value in predicting the meningioma volumetric response to gamma knife radiosurgery (GKRS). METHODS: The retrospective study included 93 meningioma patients imaged by three Tesla MRI. Tumor morphology was quantified by calculating 337 shape, first- and second-order radiomic features from MRI obtained before GKRS. Analysis was performed on original 3D MR images and after their laplacian of gaussian (LoG), logarithm and exponential filtering. The prediction performance was evaluated by Pearson correlation, linear regression and ROC analysis, with meningioma volume change per month as the outcome. RESULTS: Sixty calculated features significantly correlated with the outcome. The feature selection based on LASSO and multivariate regression started from all available 337 radiomic and 12 non-radiomic features. It selected LoG-sigma-1-0-mm-3D_firstorder_InterquartileRange and logarithm_ngtdm_Busyness as the predictively most robust and non-redundant features. The radiomic score based on these two features produced an AUC = 0.81. Adding the non-radiomic karnofsky performance status (KPS) to the score has increased the AUC to 0.88. Low values of the radiomic score defined a homogeneous subgroup of 50 patients with consistent absence (0%) of tumor progression. CONCLUSION: This is the first report of a strong association between MRI radiomic features and volumetric meningioma response to radiosurgery. The clinical importance of the early and reliable prediction of meningioma responsiveness to radiosurgery is based on its potential to aid individualized therapy decision making.

Stereotactic radiosurgery for IDH wild type glioblastoma: an international, multicenter study.

OBJECTIVE: Isocitrate dehydrogenase (IDH) mutation status is recommended used for diagnosis and prognostication of glioblastoma patients. We studied efficacy and safety of stereotactic radiosurgery (SRS) for patients with recurrent IDH-wt glioblastoma. METHODS: Consecutive patients treated with SRS for IDH-wt glioblastoma were pooled for this retrospective observational international multi-institutional study from institutions participating in the International Radiosurgery Research Foundation. RESULTS: Sixty patients (median age 61 years) underwent SRS (median dose 15 Gy and median treatment volume: 7.01 cm3) for IDH-wt glioblastoma. All patients had histories of surgery and chemotherapy with temozolomide, and 98% underwent fractionated radiation therapy. MGMT status was available for 42 patients, of which half of patients had MGMT mutant glioblastomas. During median post-SRS imaging follow-up of 6 months, 52% of patients experienced tumor progression. Median post-SRS progression free survival was 4 months. SRS prescription dose of > 14 Gy predicted longer progression free survival [HR 0.357 95% (0.164-0.777) p = 0.009]. Fifty-percent of patients died during post-SRS clinical follow-up that ranged from 1 to 33 months. SRS treatment volume of > 5 cc emerged as an independent predictor of shorter post-SRS overall survival [HR 2.802 95% CI (1.219-6.444) p = 0.02]. Adverse radiation events (ARE) suggestive of radiation necrosis were diagnosed in 6/55 (10%) patients and were managed conservatively in the majority of patients. CONCLUSIONS: SRS prescription dose of > 14 Gy is associated with longer progression free survival while tumor volume of > 5 cc is associated with shorter overall survival after SRS for IDH-wt glioblastomas. AREs are rare and are typically managed conservatively.

Stereotactic radiosurgery for glioblastoma considering tumor genetic profiles: an international multicenter study.

OBJECTIVE: Molecular profiles, such as isocitrate dehydrogenase (IDH) mutation and O6-methylguanine-DNA methyltransferase (MGMT) methylation status, have important prognostic roles for glioblastoma patients. The authors studied the efficacy and safety of stereotactic radiosurgery (SRS) for glioblastoma patients with consideration of molecular tumor profiles. METHODS: For this retrospective observational multiinstitutional study, the authors pooled consecutive patients who were treated using SRS for glioblastoma at eight institutions participating in the International Radiosurgery Research Foundation. They evaluated predictors of overall and progression-free survival with consideration of IDH mutation and MGMT methylation status. RESULTS: Ninety-six patients (median age 56 years) underwent SRS (median dose 15 Gy and median treatment volume 5.53 cm3) at 147 tumor sites (range 1 to 7). The majority of patients underwent prior fractionated radiation therapy (92%) and temozolomide chemotherapy (98%). Most patients were treated at recurrence (85%), and boost SRS was used for 12% of patients. The majority of patients harbored IDH wild-type (82%) and MGMT-methylated (62%) tumors. Molecular data were unavailable for 33 patients. Median survival durations after SRS were similar between patients harboring IDH wild-type tumors and those with IDH mutant tumors (9.0 months vs 11 months, respectively), as well as between those with MGMT-methylated tumors and those with MGMT-unmethylated tumors (9.8 vs. 9.0 months, respectively). Prescription dose > 15 Gy (OR 0.367, 95% CI 0.190-0.709, p = 0.003) and treatment volume > 5 cm3 (OR 1.036, 95% CI 1.007-1.065, p = 0.014) predicted overall survival after controlling for age and IDH status. Treatment volume > 5 cm3 (OR 2.215, 95% CI 1.159-4.234, p = 0.02) and absence of gross-total resection (OR 0.403, 95% CI 0.208-0.781, p = 0.007) were associated with inferior local control of SRS-treated lesions in multivariate models. Nine patients experienced adverse radiation events after SRS, and 7 patients developed radiation necrosis at 59 to 395 days after SRS. CONCLUSIONS: Post-SRS survival was similar as a function of IDH mutation and MGMT promoter methylation status, suggesting that molecular profiles of glioblastoma should be considered when selecting candidates for SRS. SRS prescription dose > 15 Gy and treatment volume ≤ 5 cm3 were associated with longer survival, independent of age and IDH status. Prior gross-total resection and smaller treatment volume were associated with superior local control.

[Risk factors for extended espectrum beta-lactamase producer E.coli bacteremia from urinary origin]. / Factores predictores de infección urinaria bacteriémica por Escherichia coli productor de betalactamasas de espectro extendido.

BACKGROUND AND OBJECTIVE: Although risk factors for extended spectrum beta lactamase E. coli (EBLE) infection have been explored, specific risk factors for bacteremic urinary tract infection by EBLE have been hardly analyzed. PATIENTS AND METHODS: We collected data from all patients with bacteremic urinary tract infection by E. coli attended in our hospital during 2006. Logistic regression was performed to explore predictors for EBLE bloodstream infection in this group of patients. RESULTS: EBLE was present in 19 cases (17,9%) out of 106 bacteraemia from urinary origin. Patients with bloodstream infection by EBLE were male, older, demented, living in a nursing home, with previous urologic diseases and urologic manipulation, with a higher percentage of previous urinary tract infection, previous antibiotic use, more frequent nosocomial infection, and hospital admission in the previous month. In the logistic regression analysis, only previous urologic diseases (OR 13,9; IC95% 2,5-78,2) and living in a nursing home (OR 6,5; IC95% 1,4-0,9) were associated with EBLE bacteremic urinary tract infection. CONCLUSIONS: Previous urologic disease and living in a nursing home are independent risk factors for EBLE bacteremic urinary tract infection.

[Acute myocardial infarction in patients under 45 years]. / Infarto agudo de miocardio en pacientes menores de 45 años.

INTRODUCTION AND OBJECTIVE: To evaluate the differential features of acute myocardial infarction in patients younger than 45 years old compared to older patients. PATIENTS AND METHODS: From 1995 to 1999, delays in the assistance, evaluation, and therapeutic strategies as well as complications in patients hospitalized with a diagnosis of acute myocardial infarction, have been registered in the intensive care units of the 17 hospitals participating in the PRIMVAC Register. RESULTS: During the study, 10,213 patients were registered, 6.8% younger than 45 years old (691 patients). Young patients show a greater prevalence of cigarette smoking (80.9 vs 34.1%; p < 0.0001) and hypercholesterolemia (39.9 vs 28.6%; p < 0.0001), whereas arterial hypertension, diabetes, and history of coronary disease were significantly more frequent in the older group. This subgroup reached the healthcare system at an earlier stage (120 vs 160 min; p < 0.0001). Thrombolysis was performed in 59.9% of patients younger than 45 years and in 45.9% of patients older than 45 years. Young patients were more frequently given aspirin (94.5%), heparin (70.6%), and beta-blocker drugs (38.4%), whereas patients older than 45 years were given a higher percentage of ACEI, digoxin, and inotropic drugs. Younger patients had a better prognosis and a lower mortality rate (3.5 vs 14%; p < 0.00001). CONCLUSIONS: Acute myocardial infarction in patients younger than 45 years had different clinical features and responded to different therapeutic and diagnostic approaches than acute myocardial infarction in patients over 45 years, as well as a better short-term prognosis.