SU‐F‐T‐292: Imaging and Radiation Oncology Core (IROC) Houston QA Center's Anthropomorphic Phantom Program

Abstract

Purpose:To describe the results of IROC Houston's international and domestic end‐to‐end QA phantom irradiations.Methods:IROC Houston has anthropomorphic lung, liver, head and neck, prostate, SRS and spine phantoms that are used for credentialing and quality assurance purposes. The phantoms include structures that closely mimic targets and organs at risk and are made from tissue equivalent materials: high impact polystyrene, solid water, cork and acrylic. Motion tables are used to mimic breathing motion for some lung and liver phantoms. Dose is measured with TLD and radiochromic film in various planes within the target of the phantoms.Results:The most common phantom requested is the head and neck followed by the lung phantom. The head and neck phantom was sent to 800 domestic and 148 international sites between 2011 and 2015, with average pass rates of 89% and 92%, respectively. During the past five years, a general upward trend exists regarding demand for the lung phantom for both international and domestic sites with international sites more than tripling from 5 (2011) to 16 (2015) and domestic sites doubling from 66 (2011) to 152 (2015). The pass rate for lung phantoms has been consistent from year to year despite this large increase in the number of phantoms irradiated with an average pass rate of 85% (domestic) and 95% (international) sites. The percentage of lung phantoms used in combination with motions tables increased from 38% to 79% over the 5 year time span.Conclusion:The number of domestic and international sites irradiating the head and neck and lung phantoms continues to increase and the pass rates remained constant. These end‐to‐end QA tests continue to be a crucial part of clinical trial credentialing and institution quality assurance.This investigation was supported by IROC grant CA180803 awarded by the NCI.