Toxicities Affecting Quality of Life After Chemo-IMRT of Oropharyngeal Cancer: Prospective Study of Patient-Reported, Observer-Rated, and Objective Outcomes

Abstract

To test the hypothesis that intensity modulated radiation therapy (IMRT) aiming to spare the salivary glands and swallowing structures would reduce or eliminate the effects of xerostomia and dysphagia on quality of life (QOL). In this prospective, longitudinal study, 72 patients with stage III-IV oropharyngeal cancer were treated uniformly with definitive chemo-IMRT sparing the salivary glands and swallowing structures. Overall QOL was assessed by summary scores of the Head Neck QOL (HNQOL) and University of Washington QOL (UWQOL) questionnaires, as well as the HNQOL "Overall Bother" question. Quality of life, observer-rated toxicities (Common Toxicity Criteria Adverse Effects scale, version 2), and objective evaluations (videofluoroscopy assessing dysphagia and saliva flow rates assessing xerostomia) were recorded from before therapy through 2 years after therapy. Correlations between toxicities/objective evaluations and overall QOL were assessed using longitudinal repeated measures of analysis and Pearson correlations. All observer-rated toxicities and QOL scores worsened 1-3 months after therapy andimproved through 12 months, with minor further improvements through 24 months. At 12 months, dysphagia grades 0-1, 2, and 3, were observed in 95%, 4%, and 1% of patients, respectively. Using all posttherapy observations, observer-rated dysphagia was highly correlated with all overall QOL measures (P<.0001), whereas xerostomia and mucosal and voice toxicities were significantly correlated with some, but not all, overall QOL measures, with lower correlation coefficients than dysphagia. Late overall QOL (≥6 or ≥12 months after therapy) was primarily associated with observer-rated dysphagia, and to a lesser extent with xerostomia. Videofluoroscopy scores, but not salivary flows, were significantly correlated with some of the overall QOL measures. After chemo-IMRT, although late dysphagia was on average mild, it was still the major correlate of QOL. Further efforts to reduce swallowing dysfunction are likely to yield additional gains in QOL.