Does variation in swallowing organs-at-risk (SWOAR) delineation impact on predicted swallowing dysfunction for PATHOS trial patients?

Higgins, Emma, Palaniappan, Nachi and Nabi, Zohal , et al. (2022) Does variation in swallowing organs-at-risk (SWOAR) delineation impact on predicted swallowing dysfunction for PATHOS trial patients? Clinical Oncology, 34 (Supplement 3). (doi:10.1016/j.clon.2022.09.029).

Abstract

Category: clinical trials development/outcomes

Purpose: to determine if variation between gold standard (GS) SWOAR contours and submitted on-trial outlines led to significant differences in normal tissue complication probability for physician-scored radiation-associated dysphagia at six months (NTCPD6).

Methods and materials: the dataset consisted of 78 patients recruited into arms B1 and C2 of the trial from July 2007 to February 2020 who had submitted SWOAR contours available for review. Retrospective analysis, based on visual evaluation, determined that protocol violations in SWOAR contours existed. Submitted contours (SC) (guided by the PATHOS swallowing atlas) were compared against GS contours outlined on all 78 cases by a single investigator (EH). The mean dose of the supraglottic larynx and superior pharyngeal constrictor was determined for both the GS and SC, then used to calculate the predicted NTCPD6 for each by applying the predicted model of Christianen et al.The difference between the two NTCPD6 for each case was then calculated.

Results: the mean NTCPD6 for all GS contours was 17% risk of dysphagia at six months. The difference between GS and SC mean was 0.3% (95% CI 14.8–18.6; SD 8.4; p=0.775). The individual differences for each GS versus SC ranged between −2.9% to 6.2% with only two cases having a difference greater than 4%.

Conclusion: we have shown that while protocol deviations did exist for on-trial cases, there was no statistically significant impact on predicted NTCPD6. Our findings widen the applicability of previously published data on benchmark cases to patients recruited to an ongoing UK prospective clinical trial.

This record has no associated files available for download.

Contributors

Author: Chris Hurt

Download statistics