Purpose Variation in target volume delineation represents a significant hurdle in clinical trials involving conformal radiotherapy. We sought to determine the impact of a consensus guideline-based visual atlas on contouring of target volumes. Methods A representative case and target volume delineation instructions derived from a proposed rectal cancer clinical trial involving conformal radiotherapy were contoured (Scan1) by 14 physician observers and a reference expert. Gross tumor volume (GTV), and 2 clinical target volumes (CTVA, comprising internal iliac, pre-sacral, and peri-rectal nodes, and CTVB, external iliac nodes) were contoured. Observers were randomly assigned to receipt (Group_A) /non-receipt (Group_B) of a consensus guideline and atlas for anorectal cancers, then instructed to re-contour the same case/images (Scan2). Observer variation was analyzed volumetrically using conformation number (CN, where CN=1 equals a total agreement). Results In 14 evaluable contour sets (1 expert, 7 Group_A, 6 Group_B), there was greater agreement for GTV (mean CN 0.75) than CTVs (mean CN 0.46–0.65). Atlas exposure for Group_A led to a significant increased inter-observer agreement for CTVA (mean initial CN 0.68, post-atlas 0.76; p=0.03), as well as increased agreement with the expert reference (initial mean CN 0.58, 0.69 post-atlas; p=0.02). For GTV and CTVB, neither inter-observer nor expert agreement was altered after atlas exposure. Conclusion Consensus guideline atlas implementation resulted in a detectable difference in inter-observer agreement and greater approximation of expert volumes for CTVA, but not GTV or CTVB, in the specified case. Visual atlas inclusion should be considered as a feature in future clinical trials incorporating conformal radiotherapy.

Salivary gland tumors are rare, clinically diverse neoplasms that represent less than 1% of all malignancies. In locoregional recurrent or metastatic disease, systemic therapy is the standard approach. While numerous small phase II studies have evaluated the activity of cytotoxic agents, either alone or in combination, the response rates are generally modest with objective response rates ranging from 15%-50%. Duration of response is cited in the range of 6-9 months. Given this, further evaluation of novel therapies is mandatory in these diseases. With the emergence of molecular targeted therapy, these tumors become optimal candidates for trials of investigational drugs and established drugs for new indications. Of note, given the often indolent nature of disease, only patients with progressive disease should be enrolled and treated on these clinical trials. Study designs must incorporate stringent inclusion criteria to enable accurate reporting of disease response and stabilization. With dedication and co-operation, patients with these rare neoplasms can be accrued to clinical trials and the establishment of new treatment guidelines will be forthcoming.

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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 Co gamma-rays at 0.6 Gy min Filgrastim (10 μg kg) was administered beginning on Day 1 post-exposure and continued daily until neutrophil counts were ≥2,000 μL 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.