InHANSE Institute of Head and Neck Studies and Education Contact Us


Name:   Post-operative adjuvant treatment for HPV-positive tumours

PATHOS is a multicentre, randomised phase II/III study. Approximately 242 patients will be recruited to the phase II study which is powered to show a 10 point difference in MD Anderson Dysphagia Inventory (MDADI) score (primary endpoint) between patients receiving standard adjuvant treatment and those receiving reduced intensity adjuvant treatment (either lower dose radiotherapy or no chemotherapy). The anticipated follow-on phase III study will require >800 patients.



Summary & Eligibility:

This study aims to identify the best way of treating oropharyngeal cancers that are caused by HPV. At the moment, cancers caused by HPV are treated like any other cancer in the Head and Neck and the survival rate is very good. This study is looking to see if the treatment can be modified to reduce the risk of side-effects caused by the treatment, without reducing the chance of curing the cancer.

In cases where the cancer is suitable for surgery, it is often followed by radiotherapy or radiotherapy combined with chemotherapy to try and reduce the risk of the cancer returning in the future. However, these treatments can add to the side-effects. One common side effect of current treatment is a change in the ability to swallow properly, which can be permanent.

Some doctors are reducing the amount of radiotherapy and chemotherapy that is given during treatment to try to reduce the chance of side effects. However, no one has collected data in the right way after surgery to be able to know whether or not this is the best thing to do. PATHOS is looking to do this so that we know for sure that swallowing problems after treatment can be reduced without reducing the chance of curing the tumour.


  • Aged 18 years or over
  • Histologically confirmed squamous cell carcinoma of the oropharynx
  • Clinician’s decision to treat with primary transoral resection and neck dissection
  • Patients considered fit for surgery and adjuvant treatment



  • Known HPV negative squamous cell carcinomas of the head and neck
  • N2c-N3 nodal disease.
  • Unresectable retropharyngeal node involvement.
  • Current smokers with N2b disease even if HPV-positive
  • Any pre-existing medical condition likely to impair swallowing function and/ or a history of pre-existing swallowing dysfunction prior to index oropharyngeal cancer.
  • Distant metastatic disease
  • History of malignancy in the last 5 years, except basal cell carcinoma of the skin or carcinoma in situ of the cervix.
  • Women who are pregnant or breastfeeding.





 Velindre NHS Trust

Study Coordinator

Wales Cancer Trials Unit
School of Medicine 
Cardiff University 
6th Floor 
Neuadd Meirionnydd 
Heath Park 
CF14 4YS

Study Schema:

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