The 5-year survival for Head and Neck squamous cell carcinoma (HNSCC) across all TNM stage groups is approximately 50%. Patients who are present with stage I \& II disease have significantly better survival. When a patient presents to their general practitioner (GP) with symptoms suggestive of HNSCC, they may be referred for urgent specialist input through the suspected cancer referral (SCR) pathway, which include dedicated neck lump clinics. HNSCC is known to shed fragments of DNA, called circulating tumor DNA (ctDNA) into the bloodstream. The investigators have developed novel ultra-sensitive (\>90% sensitivity) next generation sequencing (NGS) assay for circulating HPV DNA in patients with non-metastatic locally advanced head and neck cancer. The use of ultra-sensitive NGS assay for detection of ctDNA using a simple blood test (liquid biopsy) holds a great promise for cancer screening and early diagnosis and can lead to better survival results and less disease burden. With a quicker turnaround (1-2 weeks), the liquid biopsy can help expedite the patient journey through the cancer pathways reducing the incidence of cancer target breaches. In order to design studies to test this hypothesis the investigators require preliminary data quantifying sensitivity and specificity of the assay in this setting.