Epidemiology of adenoid cystic carcinoma in the United States.

Abstract

e13600 Background: Adenoid cystic carcinoma (ACC) is a rare malignancy of the secretory glands, accounting for approximately 1% of head and neck cancers and 10% of salivary gland neoplasms. ACC primarily occurs in the major and minor salivary glands; however, it is found in other sites of the head and neck, breast, female genital tract, prostate and skin. There is limited scientific literature on the epidemiology of ACC and no published incidence or prevalence estimates across all anatomic sites. Methods: Using data from the Surveillance, Epidemiology, and End Results (SEER) 18 registries, ACC cases were identified by International Classification of Diseases for Oncology 3rd Edition histology codes. Data from 2012-2016 were used to estimate age-adjusted incidence rates (IR) and 5-year limited duration prevalence (LDP). Data from 2000-2016 were used to approximate 16-year LDP. IR and LDP were estimated overall and by age, sex and race. IR was calculated for each anatomic site. Total incident and prevalent cases were projected using the 2020 US Census population. Analyses were conducted in SEER*Stat (v8.3.6) and SAS 9.4. Results: In the US, ACC age-adjusted IR was 0.35 per 100,000 and 5- and 16-year LDP were 1.48 and 3.24 per 100,000, respectively (Table). ACC IR and LDP (per 100,000) were highest in those aged 75-79 years (IR 1.45; 5-year LDP 5.82; 16-year LDP 14.25) and in females, and lowest among Native Americans/Alaska Natives. ACC IR (per 100,000) were highest in the oral cavity and pharynx (IR 0.19), salivary glands (IR 0.12), respiratory system (IR 0.07) and breast (IR 0.05). As of January 1, 2020, 10,777 patients were living with ACC in the US who had been diagnosed 2000-2016. Conclusions: This study describes the US epidemiology of ACC across all anatomic sites and provides incidence and prevalence estimates not currently published in the literature. Improving understanding of the epidemiology of this rare cancer has important implications for the development of effective clinical and public health interventions. [Table: see text]