Comparisons of Patient-Reported Quality of Life and Swallowing Scores of Mucosal Sparing Radiation vs. Standard of Care for Oropharyngeal Tumors

Abstract

<h3>Purpose/Objective(s)</h3> We hypothesized mucosal sparing radiation therapy (MSRT) would result in improved patient-reported quality of life (QOL) and modified barium swallowing impairment scores (MBSImp) compared to standard of care (SOC) post-operative adjuvant radiation for human papillomavirus related (HPV) oropharyngeal squamous cell carcinoma (OPSCC). <h3>Materials/Methods</h3> The results of two institutional prospective studies, the SOC arm of MC1675 (DART) and a MSRT trial, were compared to assess for differences in QOL and MBSImp. Both trials were performed with patients undergoing transoral surgery with negative margins and neck dissection. The SOC was 60 Gy to the primary mucosal site and at-risk nodal regions while MSRT excluded the primary mucosal site primarily using proton therapy. Chemotherapy was delivered in both as indicated. Shared endpoints between the studies included EORTC HN-35 (HN35) at baseline, end of treatment (EOT), 3-, 6-, 12-, 24-, and 36-months posttreatment and MBSimp studies at baseline and 12 months posttreatment. Baseline adjusted mixed models, with adjustments for multiple comparisons, were utilized to test the effect of treatment arm over time and their interaction, with statistical significance set at p<0.05. <h3>Results</h3> 127 patients were included, 64 from the SOC and 63 from the MSRT trial. Significant differences in patient characteristics included smoking history, insurance coverage, use of chemotherapy, and pathologic T and N categories. After treatment, improved QOL scores were significantly associated with MSRT for HN35 domains: pain, swallowing, speech problems, trouble with social eating, trouble with social contact, less sexuality, opening mouth, dry mouth, pain killers, nutritional supplements, feeding tube, and weight loss. When considering the interaction between treatment and time, the largest QOL difference occurred acutely (<3 months post-RT) with significant differences in pain, swallowing, senses problems, speech problems, trouble with social eating, trouble with social contact, less sexuality, opening mouth, dry mouth, sticky saliva, and feeling ill. Better scores with MSRT for trouble with social eating, pain, and dry mouth persisted 3 months post-RT, while no significant differences remained 6 months post-RT. When adjusted for baseline patient characteristics MSRT was still associated with superior scores for swallowing, senses problems, trouble with social eating, less sexuality, and feeding tube use. MBSimp from baseline to 12 months post-RT showed worsening of oral impairment (imp) score and overall imp score for SOC but not for MSRT. At 12 months MSRT was associated with less oral imp and overall imp than SOC. <h3>Conclusion</h3> MSRT for HPV+ OPSCC is associated with higher QOL scores compared to current SOC treatment in the acute and subacute setting and higher MBSimp scores at 12 months. Adding MSRT to the DART regimen for select HPV OSCC patients will be further studied.