In some cases, head and neck cancer produce early warning signs that can lead to early diagnosis and a high probability of cure. For example, hoarseness frequently occurs in the very earliest laryngeal glottic cancers. Up to 80 percent of early oral cancers will demonstrate erythroplasia.

Referred otalgia may accompany a cancer of the larynx, pharynx or oral cavity. In addition, a persistent sore throat for longer than two weeks in a patient with a smoking history should arouse suspicion for a possible cancer in the larynx and/or pharynx.

Epistaxis, nasal obstruction, and serous otitis media can all herald a nasopharyngeal cancer. Early cancer in many sites, e.g., the epiglottis, pyriform sinus, nasopharynx and paranasal sinuses, are silent with few signs. Although not an early sign, a neck mass may be the first presenting symptom. Any high-risk patient with a neck mass should be thoroughly evaluated for a head and neck primary cancer. A non-healing ulcer, dysphagia or a submucosal mass may also serve as warning signs of potential carcinomas.