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Cressman S.,Canadian Center for Applied Research in Cancer Control | Browman G.P.,Canadian Center for Applied Research in Cancer Control | Browman G.P.,Vancouver Island Cancer Center | Browman G.P.,University of British Columbia | And 7 more authors.
Oncologist | Year: 2015

Background. Scientific advances have led to the discovery of novel treatments with high prices. The cost to publicly fund high-cost drugs may threaten the sustainability of drug budgets in different health care systems. In oncology, there are concerns that health-benefit gains are diminishing over time andthattheeconomic evidence to support funding decisions is too limited. Methods. To assess the additional costs and benefits gained from oncology drugs over time, we used treatment protocols and efficacy results from U.S. Food and Drug Administration recordsto calculate cost-effectiveness ratios for drugs approved to treat first- and second-line metastatic or advanced breast, colorectal, and non-small cell lung cancer during the years 1994-2013. We assessed reimbursement recommendations reached by health technology assessment agencies in the U.K., Australia, and Canada. Results. Cost-effectiveness ratios were calculated for 50 drugs approved by theU.S. regulator.Themore recent approvalswere often based on surrogate efficacy outcomes and had extremely high costs, often triple the costs of drugs approved in previous years. Over time, the effectiveness gains have increased for some cancer indications; however, for other indications (nonsmall cell lung and second-line colorectal cancer), themagnitude of gains in effectiveness decreased. Reimbursement recommendations for drugs with the highest cost-effectiveness ratios were the most inconsistent. Conclusion. Evaluation oftheclinicalbenefitsthatoncologydrugs offer as a function of their cost has become highly complex, and for some clinical indications, health benefits are diminishing over time.There is an urgent need for better economic evidence from oncology drug trials and systematic processes to inform funding decisions. © AlphaMed Press 2015.

Basran P.S.,Vancouver Island Cancer Center | Basran P.S.,University of Victoria | Robertson A.,University of Victoria | Wells D.,Vancouver Island Cancer Center | Wells D.,University of Victoria
Medical Physics | Year: 2011

Purpose: To design a postprocessing 3D adaptive median filter that minimizes streak artifacts and improves soft-tissue contrast in postoperative CT images of brachytherapy seed implantations. Methods: The filter works by identifying voxels that are likely streaks and estimating more reflective voxel intensity by using voxel intensities in adjacent CT slices and applying a median filter over voxels not identified as seeds. Median values are computed over a 5×5×5 mm region of interest (ROI) within the CT volume. An acrylic phantom simulating a clinical seed implant arrangement and containing nonradioactive seeds was created. Low contrast subvolumes of tissuelike material were also embedded in the phantom. Pre- and postprocessed image quality metrics were compared using the standard deviation of ROIs between the seeds, the CT numbers of low contrast ROIs embedded within the phantom, the signal to noise ratio (SNR), and the contrast to noise ratio (CNR) of the low contrast ROIs. The method was demonstrated with a clinical postimplant CT dataset. Results: After the filter was applied, the standard deviation of CT values in streak artifact regions was significantly reduced from 76.5 to 7.2 HU. Within the observable low contrast plugs, the mean of all ROI standard deviations was significantly reduced from 60.5 to 3.9 HU, SNR significantly increased from 2.3 to 22.4, and CNR significantly increased from 0.2 to 4.1 (all P<0.01). The mean CT in the low contrast plugs remained within 5 HU of the original values. Conclusion: An efficient postprocessing filter that does not require access to projection data, which can be applied irrespective of CT scan parameters has been developed, provided the slice thickness and spacing is 3 mm or less. © 2011 American Association of Physicists in Medicine.

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