De‐intensified adjuvant (chemo)radiotherapy versus standard adjuvant chemoradiotherapy post transoral minimally invasive surgery for resectable HPV‐positive oropharyngeal carcinoma

Background More than 400,000 cases of oropharyngeal squamous cell cancer (OPSCC) are diagnosed every year worldwide and this is rising. Much of the increase has been attributed to human papillomavirus (HPV). HPV‐positive OPSCC patients are often younger and have significantly improved survival relative to HPV‐negative patients. Traditional management of OPSCC has been with radiotherapy with or without chemotherapy, as this was shown to have similar survival to open surgery but with significantly lower morbidity. Techniques have evolved, however, with the development of computerised planning and intensity‐modulated radiotherapy, and of minimally invasive surgical techniques. Acute and late toxicities associated with chemoradiotherapy are a significant burden for OPSCC patients and with an ever‐younger cohort, any strategies that could decrease treatment‐associated morbidity should be investigated. Objectives To assess the effects of de‐intensified adjuvant (chemo)radiotherapy in comparison to standard adjuvant (chemo)radiotherapy in patients treated with minimally invasive transoral surgery (transoral robotic surgery or transoral laser microsurgery) for resectable HPV‐positive oropharyngeal squamous cell carcinoma. Search methods The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 26 April 2018. Selection criteria Randomised controlled trials (RCTs) in patients with carcinoma of the oropharynx (as defined by the World Health Organization classification C09, C10). Cancers included were primary HPV‐positive squamous cell tumours originating from the oropharyngeal mucosa. Tumours were classified as T1‐4a with or without nodal spread and with no evidence of distant metastatic spread. The intervention was minimally invasive transoral surgery followed by de‐intensified adjuvant therapy (either omission of chemotherapy or reduced‐dose radiotherapy). The comparator was minimally invasive transoral surgery followed by standard concurrent chemoradiotherapy or standard‐dose radiotherapy. The treatments received were of curative intent and patients had not undergone any prior intervention, other than diagnostic biopsy. Data collection and analysis We used the standard methodological procedures expected by Cochrane. Our primary o