Non-human Primate Total-body Irradiation Model with Limited and Full Medical Supportive Care Including Filgrastim for Biodosimetry and Injury Assessment.

An assessment of multiple biomarkers from radiation casualties undergoing limited- or full-supportive care including treatment with filgrastim is critical to develop rapid and effective diagnostic triage strategies. The efficacy of filgrastim with full-supportive care was compared with results with limited-supportive care by analyzing survival, necropsy, histopathology and serial blood samples for hematological, serum chemistry and protein profiles in a non-human primate (Macaca mulatta, male and female) model during 60-d post-monitoring period following sham- and total-body irradiation with 6.5 Gy 60Co gamma-rays at 0.6 Gy min-1 Filgrastim (10 µg kg-1) was administered beginning on Day 1 post-exposure and continued daily until neutrophil counts were ≥2,000 µL-1 for two consecutive days. Filgrastim and full-supportive care significantly decreased the pancytopenia duration and resulted in improved animal survival and recovery compared to animals with a limited-supportive care. These findings also identified and validated a multiparametric biomarker panel to support radiation diagnostic device development.

Radiologists: The Unsuspecting Subject Matter Experts.

The social and political climates are changing rapidly in the United States and the world at large. The threat of a chemical, biologic, radiologic, and/or nuclear event is a rising concern to many. The current Ebola crisis has shed light on health care providers' preparedness for such an event. Radiologists, including radiation oncologists, nuclear medicine specialists, and all radiology subspecialists are considered "subject matter experts" in this area and are likely to be called upon in response to a radiation incident. Although others, such as radiation safety officers, provide important expertise, the clinical leadership will be the responsibility of physicians and other health care providers. However, many radiologists are unaware that they are considered subject matter experts who may be called on to assist, should their local hospital's emergency department need to take care of casualties from a radiation incident. A mass-casualty situation with hundreds of patients would require the immediate assistance of all available medical providers. Radiologists are primed and positioned to take the lead in ensuring preparedness of their local hospital and community, through emergency planning for a radiologic incident, given their combined medical and radiation physics knowledge. Therefore, increasing the skills of radiologists first is the more prudent approach in such planning. This preparation can be done through understanding of the critical components of such scenarios: the threat, types of radiation incidents, contamination, detection, decontamination, and acute radiation syndrome and its treatment. Once the necessary knowledge supplementation has been completed, radiologists can participate in educating their fellow medical colleagues and health care staff, and assist in the radiation-related aspects of an "all hazards" emergency department response, decreasing "radiophobia" in the process.

Prospective randomized double-blind pilot study of site-specific consensus atlas implementation for rectal cancer target volume delineation in the cooperative group setting.

PURPOSE: Variations in target volume delineation represent a significant hurdle in clinical trials involving conformal radiotherapy. We sought to determine the effect of a consensus guideline-based visual atlas on contouring the target volumes. METHODS AND MATERIALS: A representative case was contoured (Scan 1) by 14 physician observers and a reference expert with and without target volume delineation instructions derived from a proposed rectal cancer clinical trial involving conformal radiotherapy. The gross tumor volume (GTV), and two clinical target volumes (CTVA, including the internal iliac, presacral, and perirectal nodes, and CTVB, which included the external iliac nodes) were contoured. The observers were randomly assigned to receipt (Group A) or nonreceipt (Group B) of a consensus guideline and atlas for anorectal cancers and then instructed to recontour the same case/images (Scan 2). Observer variation was analyzed volumetrically using the conformation number (CN, where CN = 1 equals total agreement). RESULTS: Of 14 evaluable contour sets (1 expert and 7 Group A and 6 Group B observers), greater agreement was found for the GTV (mean CN, 0.75) than for the CTVs (mean CN, 0.46-0.65). Atlas exposure for Group A led to significantly increased interobserver agreement for CTVA (mean initial CN, 0.68, after atlas use, 0.76; p = .03) and increased agreement with the expert reference (initial mean CN, 0.58; after atlas use, 0.69; p = .02). For the GTV and CTVB, neither the interobserver nor the expert agreement was altered after atlas exposure. CONCLUSION: Consensus guideline atlas implementation resulted in a detectable difference in interobserver agreement and a greater approximation of expert volumes for the CTVA but not for the GTV or CTVB in the specified case. Visual atlas inclusion should be considered as a feature in future clinical trials incorporating conformal RT.