Salivary Gland Cancer Incidence in the United States

Objectives: Salivary gland cancers (SGC) are uncommon malignancies accounting for less than 3% of all head and neck cancers. The etiology of SGC is poorly understood and understanding disease incidence and distribution among populations is crucial. The objective of this study is to examine the salivary gland cancer age-adjusted incidence (AAIR) and relative survival among the various races in the United Sates: White, Black, Hispanic, American Indian and Asian/Pacific Islander populations.

Methods: We used the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database to obtain the demographic and clinicopathologic information and examined the SGC incidence rates and survivals among all races in the U.S. during 1992-2004.

Results: The race-specific AAIR of SGC in males ranged between 0.91 and 1.65 and in females, 0.67 and 0.97. Both among males and females, the highest AAIR was seen in the White population. A striking finding was that males in all races have predominantly poorly differentiated SGC compared to females who have predominantly moderately differentiated SGC. This corresponds to the poor 5-year survival rates in males compared to females. Regional metastasis was higher in White & Hispanic males whereas distant metastasis was seen commonly in Black males followed closely by white males. Black males and females had the lowest 5-year survival rates.

Conclusions: Whites have the highest incidence rates among the diverse racial groups in the United States. The survival rates of SGC are dismal despite advances in therapeutic modalities in the recent past. Further research is needed to understand these rare yet high mortality malignancies.