https://www.selleckchem.com/products/AR-42-HDAC-42.html Oral breast cancer prevention medications entail systemic exposure, limiting acceptance by high-risk women. Delivery through the breast skin, although an attractive alternative, requires demonstration of drug distribution throughout the breast. We conducted a randomized double-blind, placebo-controlled phase II clinical trial comparing telapristone acetate, a progesterone receptor antagonist, administered orally (12 mg/day) or transdermally (12 mg/breast) for 4 ± 1 weeks to women planning mastectomy. Plasma and tissue concentrations, measured at five locations in the mastectomy specimen using liquid chromatography tandem mass spectrometry were compared. In 60 evaluable subjects, median drug concentration (ng/g tissue) was 103 (interquartile range (IQR) 46.3-336) in the oral vs. 2.82 (IQR 1.4-5.5) in the transdermal group. Despite poor dermal permeation, within-breast drug distribution pattern was identical in both groups (R2 = 0.88, P = 0.006), demonstrating that transdermally and orally delivered drug is distributed similarly through the breast, and is strongly influenced by tissue adiposity (P less then 0.0001). Other skin-penetrant drugs should be tested for breast cancer prevention. MRI is the gold-standard imaging modality for brain tumor diagnosis and delineation. The purpose of this work was to investigate the feasibility of performing brain stereotactic radiosurgery (SRS) with a 0.35T MRI-guided linear accelerator (MRL) equipped with a double-focused multileaf collimator (MLC). Dosimetric comparisons were made vs a conventional C-arm-mounted linac with a high-definition MLC. The quality of MRL single-isocenter brain SRS treatment plans was evaluated as a function of target size for a series of spherical targets with diameters from 0.6cm to 2.5cm in an anthropomorphic head phantom and six brain metastases (max linear dimension=0.7-1.9cm) previously treated at our clinic on a conventional linac. Each targ