Comparison of mortality trends in patients with non-salivary gland and salivary gland adenoid cystic carcinoma in the United States population.

Abstract

e17584 Background: Adenoid cystic carcinoma is the most common histological subtype of malignancy seen in major and minor salivary glands. Although indolent they tend to recur and progress. Adenoid cystic carcinoma also arises from other structures such as lacrimal glands and trachea. This study compares the incidence-based mortality between patients who have salivary and no-salivary origin adenoid cystic carcinomas of the head and neck region over the period of 2000 to 2014. Methods: A nation-wide analysis was conducted utilizing the Surveillance, Epidemiology, and End Results (SEER) Database from the years 2000 to 2014. Incidence-based mortality for all stages of adenoid cystic carcinoma was queried and the results were grouped by race (Caucasian/White, African American/Black, American Indian/Alaskan native and Asian/Pacific Islander) and gender. All stages were included in the analysis. T-test was used to determine statistically significance difference between various subgroups. Linearized trend lines were used to visualize the mortality trends of all sub groups. Results: Incidence-based mortality for salivary gland adenoid cystic carcinomas in African American/Black patients is comparable to Caucasian/White patients despite a higher incidence in Caucasian/White patients (no statistically significant difference was noted). Also, the incidence-based mortality for non-salivary gland adenoid cystic carcinomas of the head and neck region in African American/Black patients was similar to Caucasian/White patients. Essentially no racial difference in mortality was noted between salivary and non-salivary gland tumors. Comparison of mortality between genders in both races in salivary and non-salivary gland tumors also did not show any statistically significant difference. Conclusions: This study showed that adenoid cystic carcinoma of non-salivary gland origin have the same mortality trends as that from salivary gland origin in both Caucasian/White and American/Black patients and in both genders. Given such uniformity, genetic and environmental factors may not play significant role in the progression and outcomes of this disease. Hence, adenoid cystic carcinoma may be treated with similar therapeutic approaches regardless of the origin, gender and race of the patient.