Esophageal Cancer in Brunei Darussalam over a three Decade Period: an Epidemiologic Study of Trends and Differences between Genders and Racial Groups

Background: Carcinoma of the esophagus is associated with significant morbidity and mortality. The mostcommon subtype is squamous cell carcinoma (SCC). In the past three decades, the incidence of SCC has beenreported to be decreasing whereas esophageal adenocarcinoma (AC) is increasing. This study assessed the trendof esophageal cancer in Brunei Darussalam over a three decades period. Materials and
Methods: The NationalCancer registry was searched for esophageal cancers from 1986 to 2012. Data on age, gender, racial groups(Malays, Chinese, Indigenous and foreign nationals) and histology type were collected. The rate (ASR) and AgeSpecific Incidence rate (ASIR) were calculated.
Results: The predominant tumor type was SCC which accountedfor 89% of all esophageal cancer. The gender ratio was 2.25: 1 (male: female) and the mean age at diagnosis was66.9±12.9 years, significantly younger for esophageal AC (57.2±16.0) compared to SCC (68.1±12.0, p<0.05), andamong the foreign nationals (p<0.05 for trend). The proportions of SCC among all esophageal cancers in thevarious racial groups were: Malays (87.8%), Chinese (100%), Indigenous (100%) and foreign nationals (20%).None of the Chinese and Indigenous groups were diagnosed with esophageal AC. The overall ASR for esophagealcancer was 2.1/100,000; 2.0/100,000 for SCC with a declining trend and 0.17/100,000 for esophageal AC, withoutany trend observed. Among the two major racial groups; the Chinese has higher ASR (3.42/100,000) comparedto the Malays (ASR 0.95/100,000).
Conclusions: SCC is the predominant tumor type of esophageal cancer inBrunei Darussalam and more common among the Chinese. There was a declining trend in the incidence of SCCbut not for esophageal AC.