Rorschach radiation.

The CATNON trial evaluated the benefit of adding concurrent and adjuvant temozolomide to radiation in patients with 1p/19q non-codeleted high grade gliomas. This study describes the results of the radiation quality assurance process. Each center who participated had to submit the radiation plan for their first treated patient. To review, the GTV was to include the resection cavity and any abnormalities on T2 and/or FLAIR. The CTV was a 1.5-2 cm expansion with a single PTV receiving 59.4 Gy. After central review, nearly 50%(!) of radiation plans had unacceptable variations, mostly due to improper target and organs at risk delineation. We mainly feel sorry for the person whose contours ended up in Figure 2 because they clearly simply confused their brainstem contour with a post-op prostate volume. TBL: The delineation of targets and organs at risk introduces significant practice variability, which could have a big impact on large scale trial and practice outcomes. | Abrunhosa-Branquinho, Radiother Oncol 2018