A 53-year-old previously healthy man visited his physician with a chief complaint of a sore throat of 6 weeks’ duration. The patient reported pain on swallowing but did not have a fever, cough, or congestion. He did not smoke and had an occasional glass of wine with dinner. A physical examination revealed a 3-cm mass on the left side of the posterior pharynx along with an ipsilateral 1-cm firm, immovable cervical lymph node. A referral was made to an otolaryngologist, who performed a biopsy yielding a diagnosis of squamous cell carcinoma of the posterior pharynx. The patient subsequently underwent a complete surgical resection of the primary tumor and a selective dissection of cervical lymph nodes, two of six of which had malignant cells present. Examination of the tumor specimen by situ hybridization was positive for human papillomavirus (HPV) type 16. The patient was treated additionally with external-beam radiation therapy, and there was no evidence of tumor recurrence within the initial 3 years after diagnosis.
Head and neck cancer most commonly arises as a squamous cell malignancy within the oral cavity, pharynx, or larynx. Worldwide, there are estimated to be more than half a million new head and neck cancers diagnosed each year and nearly one third of a million deaths annually from this disease. Head and neck cancer is the sixth most common type of cancer globally, ranking third highest among economically emerging countries and eighth highest among high-income countries.
In the United States, the overall occurrence of head and neck cancer has been declining for several decades, with an average annual decrease of about 1.5% per year. When examined by anatomic site of the primary malignancy, however, differing patterns are observed, with decreases in the occurrence of lip, oral cavity, and laryngeal cancers and an increasing proportion of lesions arising in the oropharynx (base of the tongue, tonsils, and pharynx). Over this same time period, there was a progressive shift to more advanced oropharyngeal malignancies (disseminated to the adjacent tissue or spread remotely) at the time of diagnosis. With more extensive tumors, one might have anticipated declining survival rates for oropharyngeal cancers, but to the contrary, 5-year survival rates have risen, and most of the improvement has been observed among patients with nonlocalized disease.
Cigarette smoking is a well-established risk factor for head and neck cancer, increasing the risk by about 10-fold. It has been estimated that four out of five of these malignancies are attributable to tobacco use. Heavy alcohol consumption has been shown to increase the risk of developing head and neck cancer independently and even more dramatically when used in combination with tobacco use. The overall declining rate of new occurrences of head and neck cancer in the United States has been attributed to falling rates of cigarette smoking.
Human papillomavirus is a small virus containing double-strained circular DNA. ...