Head and neck cancer Epidemiology

Introduction

While head and neck cancer is relatively rare in the United States, it is a more significant entity in some parts of the developing world. In the United States, the vast majority of head and neck malignancies are squamous cell carcinomas of the UADT (ie, the oral cavity, the oro- and hypopharynx, and the larynx). Approximately 90% of HNSCCs occur after exposure to tobacco and/or alcohol. Emerging information suggests that one's genetic background and exposures apart from tobacco and alcohol contribute to the risk of HNSCC as well. Ultimately, the public health goal is better prevention of these malignancies by reducing the use of tobacco and alcohol, discovering and avoiding other causative agents, and identifying the genetically susceptible. Such work will enhance both primary and secondary prevention efforts.

Descriptive Epidemiology

Incidence
In the United States, 19,400 new cases of oral cavity cancer, 8,300 new cases of pharyngeal cancer, and 9,500 new cases of laryngeal cancer will be diagnosed in 2003. Head and neck cancers account for approximately 3% of all new cancer cases in the United States annually, excluding basal and squamous cell carcinomas of the skin. The absolute incidence of oral cavity and pharyngeal cancer has been approximately 21,000 and 9,000 new cases, respectively, annually since 1985; however, the number of new cases of laryngeal cancer has steadily declined since 1993, when 12,600 new cases were diagnosed.

In the United States, approximately 1 in 3 oral cavity/pharyngeal cancers occur in women while only 1 in 5 laryngeal cancers occur in women. The incidence rates in men are double the rates in women for oral cavity/pharyngeal cancers and triple the rates in women for laryngeal cancer. Since the mid 1980s, incidence rates (age-adjusted to the 2000 US standard) for both oral cavity/pharyngeal cancer and laryngeal cancer have steadily declined in men to 15.2 of 100,000 and 6.9 of 100,000, respectively, in 1999. However, during the same time period these rates have been relatively stagnant in women. While black and white women have similar rates of oral cavity/pharyngeal cancer, black men have a 30% higher rate of oral cavity/pharyngeal cancer than white men. Both black men and women have double the rate of laryngeal cancer of white men and women, respectively. Hispanics have the lowest rates of oral cavity/pharyngeal cancer, and Asians have the lowest rates of laryngeal cancer.

The median age at diagnosis for HNSCC is approximately 60 years, but the incidence of these cancers in young adults (age < 40 years) appears to be increasing. This increase has not been apparent in blacks, and carcinoma of the tongue appears to account for the majority of this increase in incidence.