Head and neck (HN) radiotherapy contour quality directly impacts local control (LC) and survival; however, few departments peer review (PR) contours prior to radiotherapy planning (RTP). This study reports outcomes of a single institution’s formal HN contour PR process.

A formal HN contour PR process was implemented. Prior to RTP, HN radiation oncologists reviewed contours, provided feedback and assigned contour grades as follows: R0 (no change), R1 (minor revision, not high risk) or R2 (major revision; high risk). The PR task was completed and the contour grade was recorded. Cochran-Armitage trend test was performed.

Pilot PR process was performed over a 7-month period for 88 patients, followed by a maintenance phase. Contours were graded as follows: R0 (N = 51), R1 (N = 20) and R2 (N = 17). Over time, the number of R2 revisions decreased (p = 0.0001); month 1 (N = 7), month 2 (N = 3), month 3 (N = 5), month 4 (N = 2) and months 5–7 (N = 0). Conversely, the number of R0 revisions improved over time (p = 0.0203); month 1 (N = 5), months 2–3 (N = 9), month 4 (N = 5), month 5 (N = 8), month 6 (N = 12) and month 7 (N = 3). Each radiation oncologist demonstrated reduction in R2 revisions during the pilot. During maintenance, all 3 radiation oncologists demonstrated low rates of R2 revisions of less than 3 cases per year.

Incorporation of HN contour PR into routine clinical workflow is feasible. The collective experience of multiple high-volume HN radiation oncologists led to improved contour quality in the pilot for each radiation oncologist and continued to ensure high quality in the maintenance phase.