Radiology
-
Purpose To determine if the combination of high cerebral blood flow (CBF) and O6-methylguanine DNA methyltransferase (MGMT) promoter methylation is associated with benefit from a second round of low-dose temozolomide (TMZ) (ie, rechallenge) in patients with glioblastoma at first recurrence. Materials and Methods The institutional review board approved this retrospective cohort study and waived the requirement for informed consent. Seventy-two patients with recurrent glioblastoma after concurrent TMZ radiation therapy were treated with a low-dose TMZ rechallenge and underwent arterial spin labeling magnetic resonance imaging. ⋯ The association between high CBF and favorable outcome was significant only in the MGMT promoter methylation group (P = .006 for TTP; P = .005 for 6-month outcome). Conclusion The combination of high CBF with MGMT methylation may be associated with benefits from a low-dose TMZ rechallenge in patients with recurrent glioblastoma. However, alternative strategies might be needed for patients with both low CBF and a lack of MGMT methylation. © RSNA, 2016 Online supplemental material is available for this article.
-
Comparative Study
Comparison of Background Parenchymal Enhancement at Contrast-enhanced Spectral Mammography and Breast MR Imaging.
Purpose To assess the extent of background parenchymal enhancement (BPE) at contrast material-enhanced (CE) spectral mammography and breast magnetic resonance (MR) imaging, to evaluate interreader agreement in BPE assessment, and to examine the relationships between clinical factors and BPE. Materials and Methods This was a retrospective, institutional review board-approved, HIPAA-compliant study. Two hundred seventy-eight women from 25 to 76 years of age with increased breast cancer risk who underwent CE spectral mammography and MR imaging for screening or staging from 2010 through 2014 were included. ⋯ Overall agreement on BPE levels between CE spectral mammography and MR imaging and among readers was substantial (κ = 0.66; 95% confidence interval: 0.61, 0.70). With both modalities, BPE demonstrated significant association with menopausal status, prior breast radiation therapy, hormonal treatment, breast density on CE spectral mammographic images, and amount of fibroglandular tissue on MR images (P < .001 for all). Conclusion There was substantial agreement between readers for BPE detected on CE spectral mammographic and MR images. © RSNA, 2016.
-
Purpose To establish the relationship between KRAS mutation status and local recurrence after image-guided ablation of lung adenocarcinoma. Materials and Methods This study consisted of a HIPAA-compliant institutional review board-approved retrospective review of 56 primary lung adenocarcinomas in 54 patients (24 men, 30 women; median age, 72 years; range, 54-87 years) treated with percutaneous image-guided ablation and with available genetic mutational analysis. KRAS mutation status and additional clinical and technical variables-Eastern Cooperative Oncology Group (ECOG) status, smoking history, stage at diagnosis, status (new primary or not), history of radiation, history of surgery, prior systemic treatment, modality of ablation, size of nodule, ablation margin, and presence of ground-glass appearance-were recorded and evaluated in relation to time to local recurrence, which was calculated from the time of ablation to the first radiographic evidence of recurrence. ⋯ At multivariate analysis, size (P = .026; sHR, 2.54) and ECOG status (P = .012; sHR, 2.23) were also independent significant predictors, whereas minimum margin (P = .066) was not. Conclusion The results of this study show that there is a relationship between KRAS mutation status and local recurrence after image-guided ablation of lung adenocarcinoma. Specifically, KRAS mutation status of the ablated lesion is a significant predictor of time to local recurrence, independent of size and margin. © RSNA, 2016.