MATERIALS AND METHODS: The cancer registry from 1986 to 2014 maintained by the State Laboratory was retrospectively reviewed. The age standardized rates (ASR) and the age specific incidence rates (ASIR) were calculated. Non NPC tumors were excluded from the study.
RESULTS: Altogether, there were a total of 450 NPC cases diagnosed accounting for 4.4% of all total cancer cases over the study period, declining from 10.3% in 1986-1990 to 2.3% in 2011-2014. The most common tumor type was the undifferentiated carcinoma (96.4%). The case characteristics were mean age 50.4 ± 14.4 years old, male 69%, and predominately Malays 74.4%, followed by Chinese 16.7%. The mean age of diagnosis increased over the study period from 45.6 ± 17.1 years (1986-1989) to 54.1 ± 12.5 years (ANOVA, p<0.01 for trend). There were no differences in the mean age of diagnosis between the ethnic groups or genders. The ASR showed a declining trend from 11.1 per 100,000 in 1986-1990 to 5.95 per 100,000 in 2011-2014, similar trends been observedfor both genders. Among the age groups, declining trends were seen in all the other age groups apart from the >70 years group. The overall ASRs for the Malays and Chinese were 7.92/100,000 and 8.83/100,000 respectively, both showing declining trends.
CONCLUSIONS: The incidence of NPC in Brunei Darussalam is comparable to rates reported from Singapore and Malaysia, but higher than rates reported from the other Southeast Asian nations. Unlike higher rates reported for Chinese compared to the Malays in other countries, the rates between the Malays and Chinese in our study was comparable. Importantly, the ASR is declining overall and for both genders and ethnic groups.
METHODS: A multi-center, prospective colonoscopy study involving 16 Asia-Pacific regions was performed from 2008 to 2015. Consecutive self-referred CRC screening participants aged 40-70 years were recruited, and each subject received one direct optical colonoscopy. The prevalence of CRC, ACN, and colorectal adenoma was compared among subjects with different FDRs affected using Pearson's χ2 tests. Binary logistic regression analyses were performed to evaluate the risk of these lesions, controlling for recognized risk factors including age, gender, smoking habits, alcohol drinking, body mass index, and the presence of diabetes mellitus.
RESULTS: Among 11,797 asymptomatic subjects, the prevalence of CRC was 0.6% (none: 0.6%; siblings: 1.1%; mother: 0.5%; father: 1.2%; ≥2 members: 3.1%, P<0.001), that of ACN was 6.5% (none: 6.1%; siblings: 8.3%; mother: 7.7%; father: 8.7%; ≥2 members: 9.3%, P<0.001), and that of colorectal adenoma was 29.3% (none: 28.6%; siblings: 33.5%; mother: 31.8%; father: 31.1%; ≥2 members: 38.1%, P<0.001). In multivariate regression analyses, subjects with at least one FDR affected were significantly more likely to have CRC (adjusted odds ratio (AOR)=2.02-7.89), ACN (AOR=1.55-2.06), and colorectal adenoma (AOR=1.31-1.92) than those without a family history. The risk of CRC (AOR=0.90, 95% confidence interval (CI) 0.34-2.35, P=0.830), ACN (AOR=1.07, 95% CI 0.75-1.52, P=0.714), and colorectal adenoma (AOR=0.96, 95% CI 0.78-1.19, P=0.718) in subjects with either parent affected was similar to that of subjects with their siblings affected.
CONCLUSIONS: The risk of colorectal neoplasia was similar among subjects with different FDRs affected. These findings do not support the need to discriminate proband identity in screening participants with affected FDRs when their risks of colorectal neoplasia were estimated.