Abstract
BACKGROUND: Radiation therapy is commonly used to treat head and neck cancer patients, and response may be improved by combining radiation with preexisting medications. Based on recent preclinical and retrospective patient data, we hypothesized that antihypertensive drugs may improve radiotherapy outcomes. METHODS: Retrospective analyses were conducted on 1077 oropharyngeal squamous cell carcinoma and 608 nasopharyngeal carcinoma patients, all of whom received radiation therapy. Univariate and multivariate analyses were conducted to assess overall survival, disease-specific survival, and locoregional control for cancer patients taking angiotensin receptor blockers (ARBs), angiotensin-converting enzyme inhibitors, calcium channel blockers, or beta blockers compared with propensity score-matched groups of patients not taking these medications. RESULTS: Oropharyngeal squamous cell carcinoma patients taking antihypertensive medications were statistically older and had higher Charlson Comorbidity Indices at diagnosis. However, these patients had statistically significant improved overall survival, disease-specific survival, and locoregional control compared with propensity score-matched oropharyngeal squamous cell carcinoma patients who were not taking antihypertensive medications, with ARB users showing the greatest improvements. Antihypertensive drugs did not affect outcomes in the nasopharyngeal carcinoma patient cohort. CONCLUSION: The use of antihypertensive medications, and particularly ARBs, was associated with improved outcomes in oropharyngeal squamous cell carcinoma patients who had more advanced age and higher Charlson Comorbidity Indices at diagnosis. This study supports future prospective testing of ARBs in conjunction with radiation therapy in this group of higher risk oropharyngeal squamous cell carcinoma patients. Additionally, this study illustrates the need to use propensity score matching to identify patient subgroups that may benefit from a given treatment in retrospective analyses.