Effectiveness Of Reduced Versus Standard Dose Radiation Therapy On Survival And Radiation Associated Toxicity In Human Papillomavirus (HPV) Associated Oropharyngeal Squamous Cell Carcinoma

Abstract

Purpose Oropharyngeal squamous cell carcinoma is a common form of head and neck cancer. A commonly occurring associated factor with this cancer is the Human Papillomavirus, which identifies an important and prevalent subgroup of patients that experience this cancer. Management for this group of people generally involves primary chemoradiotherapy or surgery with adjuvant chemoradiotherapy. Radiation therapy can however result in both acute and late-onset complications that may lead to treatment interruptions and reduced quality of life. Methodology A systematic review and meta-analysis was conducted to summarise the available literature comparing treatment of Human Papillomavirus associated Oropharyngeal Squamous Cell Carcinoma with either curative intent standard dose or de-escalated radiation therapy. A pre-defined search strategy was used across multiple databases to identify suitable articles. Two independent reviewers performed title and abstract screening against inclusion and exclusion criteria with subsequent full text review. Following screening of 1050 records, 16 studies were included and 5 individual reports had data suitable for meta-analysis. Primary outcomes included; overall survival, progression free survival, disease free survival, disease specific survival and radiation associated toxicity. Secondary outcomes included; hospital re-admissions and patient reported quality of life measures. Results Meta-analysis revealed no significant differences in two- or three-year overall survival or progression free survival between those treated with curative intent reduced versus standard dose radiation therapy. The certainty in the evidence ranged from low to very low. In general, reduced dose radiation therapy was associated with better objective and subjective swallowing outcomes, reduced gastrostomy tube requirement and improved quality of life. Conclusion Findings from this systematic review have not provided any strong evidence to support a change in management to reduced dose radiation therapy for Human Papillomavirus associated Oropharyngeal Squamous Cell Carcinoma.