Blood test shows promise for predicting treatment response in patients with advanced HPV-positive throat cancer A sensitive blood test being developed by a team of researchers at the University of Michigan Rogel Cancer Center shows promise for predicting whether patients with metastatic HPV-positive throat cancer will respond to treatment months earlier than standard imaging scans. That's according to a study, published in Oncotarget, validating the test in a small group of patients with metastatic human papillomavirus-related oropharyngeal squamous cell carcinoma -- a type of head and neck cancer that develops in the back of the mouth and in the throat.