Evidence for the approach to the diagnostic evaluation of squamous cell carcinoma occult primary tumors of the head and neck.

Metastases to the cervical lymph nodes from a occult primary (CUP) of head and neck squamous carcinomas has been increasing in presentation (HNSCC). Modern diagnostic workup, including clinical evaluation, conventional imaging, FDG-PET/CT and panendoscopy/tonsillectomy enables detection of the primary site in over half of all cases, and is associated with significantly improved survival rates. Recent studies have demonstrated the utility of novel molecular pathology and transoral surgical techniques in improving diagnosis and treatment. We present a new, evidence-based protocol incorporating these novel diagnostic modalities. It aims to identify the site of the primary tumor, and determine the stage of the disease, including extranodal extension. This information can personalise treatment recommendations, rationalise combinations of treatment modalities, and thereby potentially minimise toxicity and improving functional outcomes.