Cancers among South-East Asian Nationals in Brunei Darussalam

Chong, Vui Heng,Telisinghe, Pemasari Upali,Lim, Edwin,Tan, Jackson,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

Background: Worldwide, the incidence of cancers is increasing and is becoming a major public health issue, including those in the Asia Pacific region. South-East Asia is a region with diverse populations with different disease spectra. This study looked at the spectrum of cancers among South-East Asians working in Brunei Darussalam. Materials and Methods: The cancer registry from 1994 to 2012 maintained by the State Laboratory was retrospectively reviewed. Crude incidence rates were calculated based on the population census of 2010. Results: Altogether, there was a total of 418 cancer cases diagnosed among South-East Asians, giving an incidence of 5.1% (n=418/8,253). The affected nationals in decreasing frequency were Malaysians (53.1%), followed by Filipinos (25.8%), Indonesians (15.3%), Thais (3.8%), Myanmese (1.7%) and Vietnamese (0.2%) with no recorded cases for Singapore and the People's Republic of Laos. The overall mean age of diagnosis was $46.1{\pm}4.2$ years old, with an increasing trend over the years (p<0.05 ANOVA). The overall gender ratio was 42.3:57.7 (male:female), more females among the Filipinos and Indonesians, more males among the Thais, and equal representation among the Malaysians and the Myanmese. The most common were cancers of the digestive system (19.9%), followed by female reproductive/gynecologic system (16.0%), breast (15.6%), hematological/lymphatic (12.0%) and head/neck (8.1%). There were differences in the prevalence of cancers among the various nationalities with highest crude incidence rate among the Myanmese (141.2/100,000), followed by the Malaysian (88.5/100,000), and the Filipinos (40.6/100,000) and the lowest among the Thais (18.4/100,000), Indonesians (10.5/100,000) and the Vietnamese (6.3/100,000). Conclusions: Cancers among South-East Asian residing in Brunei Darussalam accounted for 5.1% of all cancers. The most common cancers were cancers of the digestive, gynecologic/female reproductive system and breast with certain types slowly increasing in proportions. There mean age of diagnoses was increasing.

Colorectal Cancer Screening among Government Servants in Brunei Darussalam

Chong, Vui Heng,Bakar, Suriawati,Sia, Rusanah,Lee, James,Kassim, Norhayati,Rajak, Lubna,Abdullah, Muhd Syafiq,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: This study concerns uptake and results of colorectal cancer (CRC) screening of government servant as part of the Health Screening Program that was conducted in Brunei Darussalam in 2009. Materials and Methods: Government servants above the age of 40 or with family history of CRC were screened with a single fecal occult blood test (FIT, immunohistochemistry). Among 11,576 eligible subjects, 7,360 (66.9%) returned their specimen. Subjects with positive family history of CRC (n=329) or polyps (n=135) were advised to attend clinics to arrange screening. All the subjects with positive FIT (n=142, 1.9%) were referred to the endoscopy unit for counselling for screening colonoscopy. Results: Overall only 17.7% of eligible subjects attended for screening; 54.9% (n=79/142) of positive FIT, 8.8% (n=29/329) of positive family history of CRC and none with history of polyps (n=0/135). Of these, only 54 patients (50.5%) agreed for colonoscopy, 52 (48.6%) declined as they were asymptomatic, and one was not offered (0.9%) due to his very young age. On screening colonoscopy, 12.9% (n=7) had advanced lesions including a sigmoid carcinoma in situ and six advanced polyps. The other findings included non advanced polyps (n=21), diverticular (n=11) and hemorrhoids (n=26). One patient who missed his screening colonoscopy appointment re-presented two years later and was diagnosed with advanced right sided CRC. All the advanced lesions were detected in patients with positive FIT, giving a yield of 20.5% for advanced lesions including cancers in the 5.1% FIT positive subjects. Conclusions: Our study showed screening for CRC even with a single FIT was effective. However, the uptake rate was poor with just over half of the patients agreeing to screening colonoscopy. Measures to increase public awareness are important. Since one limitation of our study was the relatively small sample size, larger studies should be conduced in future.

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

Chong, Vui Heng,Telisinghe, Pemasari Upali,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: Carcinoma of the esophagus is associated with significant morbidity and mortality. The most common subtype is squamous cell carcinoma (SCC). In the past three decades, the incidence of SCC has been reported to be decreasing whereas esophageal adenocarcinoma (AC) is increasing. This study assessed the trend of esophageal cancer in Brunei Darussalam over a three decades period. Materials and Methods: The National Cancer 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 Age Specific Incidence rate (ASIR) were calculated. Results: The predominant tumor type was SCC which accounted for 89% of all esophageal cancer. The gender ratio was 2.25: 1 (male: female) and the mean age at diagnosis was $66.9{\pm}12.9$ years, significantly younger for esophageal AC ($57.2{\pm}16.0$) compared to SCC ($68.1{\pm}12.0$, p<0.05), and among the foreign nationals (p<0.05 for trend). The proportions of SCC among all esophageal cancers in the various 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 esophageal cancer was 2.1/100,000; 2.0/100,000 for SCC with a declining trend and 0.17/100,000 for esophageal AC, without any trend observed. Among the two major racial groups; the Chinese has higher ASR (3.42/100,000) compared to the Malays (ASR 0.95/100,000). Conclusions: SCC is the predominant tumor type of esophageal cancer in Brunei Darussalam and more common among the Chinese. There was a declining trend in the incidence of SCC but not for esophageal AC.

Nasopharyngeal examination during transoral upper gastrointestinal endoscopy

Vui Heng Chong 대한소화기내시경학회 2024 Clinical Endoscopy Vol.57 No.1

LETTER TO THE EDITOR

Poor Knowledge of Colorectal Cancer in Brunei Darussalam

Chong, Vui Heng,Lim, Ai Giok,Baharudin, Hana Naqiyah,Tan, Jackson,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: Colorectal cancer (CRC) is the most common gastrointestinal cancer and the incidence is increasing in many developing countries. While it can be detected early and even prevented through screening and removal of premalignant lesions, there are barriers to screening which include low level of knowledge and awareness of CRC. This study assessed the level of knowledge of CRC in Brunei Darussalam. Materials and Methods: A total of 431 (262 male and 161 female) subjects participated in this questionnaire study. Subjects were scored on their knowledge of signs/symptoms (maximum 10 correct answers) and known risk factors for CRC (maximum 10 correct answers) and were categorised into poor (0-2), moderate (3-4) and satisfactory (5-10). Comparisons were made between the various patient factors. Results: Overall, 54.1% could not name any CRC signs/symptoms or associated risk factors. Most were not aware of any screening modalities. The overall scores for CRC signs/symptoms and risk factors were $1.3{\pm}1.39$ (range 0-6) and $0.6{\pm}1.05$ (range 0-5) respectively. Overall, the breakdown of scores was: poor (78.1%), moderate (20.3%) and satisfactory (6.2%) for signs/symptoms and poor (93.2%), moderate (6.2%) and satisfactory (0.7%) for risk factors. Higher level of education, female gender and non-Malay race were associated with higher scores for both signs/symptoms and knowledge of screening modality; however the overall scores were low. Conclusions: Our study showed that the general knowledge of CRC in Brunei Darussalam is poor. Being female, with higher levels of education and non-Malay race were associated with higher scores, but they were still generally poor. More needs to be done to increase the public knowledge and awareness of CRC.

Declining Incidence of Nasopharyngeal Carcinoma in Brunei Darussalam: a Three Decade Study (1986-2014)

Chong, Vui Heng,Telisinghe, Pemsari Upali,LIM, Edwin,Abdullah, Muhammad Syafiq,Idris, Fidah,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16

Background: Nasopharyngeal carcinoma (NPC) is linked to Epstein Barr virus infection and is particularly common in the Far East, particularly among some Chinese groups. Certain ethnicities have been reported to have low incidence of NPC. This study looked at NPC in Brunei Darussalam over a three decade period. 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 $50.4{\pm}14.4$ 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 $45.6{\pm}17.1$ years (1986-1989) to $54.1{\pm}12.5$ 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.

Profile of HER2 +ve Gastric Cancers in Brunei Darussalam

Chong, Vui Heng,Telisinghe, Pemasari Upali,Tan, Jackson,Abdullah, Muhamad Syafiq,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.5

Background: Gastric cancer is the second most common gastrointestinal cancer and is still associated with significant morbidity and mortality due to late presentation and diagnosis at advanced stages. Studies have reported that a variable proportion of gastric cancer is positive for the human epidermal growth factor receptor 2 (HER2) and patients with HER2 positive (HER2 +ve) lesions can benefit from targeted therapy. This study was conducted to assess the prevalence of HER2 +ve gastric cancers in Brunei Darussalam, a developing Southeast Asian nation. Materials and Methods: Patients were identified from the Department of Pathology registry and retrospectively reviewed. HER2 expression was assessed by immunohistochemistry and only those staining 3+were considered positive. Results: Our study included 103 cases (66 males and 37 females) with a mean age of $65.1{\pm}14.8$ years old. There were 14 cases positive for HER2 (10 males and 4 females) giving a prevalence of 13.6%. The HER2 +ve cases were significantly older ($70.6{\pm}19.3$ years old) than the negative cases ($64.2{\pm}13.8$, p=0.041) and had significantly more advanced disease (stages 3 and 4, p=0.026). There were no significant differences in gender distribution, presence of intestinal metaplasia, EBV status, Helicobacter pylori status, tumor location (proximal vs. distal) and degree of tumor differentiation (all p values >0.05). Conclusions: Our study showed that 13.6% of our gastric cancers are positive for HER2, the affected patients being older and having more advanced disease at diagnosis.

Increasing Incidence of Colorectal Cancer, Starting at a Younger Age for Rectal Compared to Colon Cancer in Brunei Darussalam

Chong, Vui Heng,Telisinghe, Pemasari Upali,Bickle, Ian,Abdullah, Muhamad Syafiq,Lim, Ediwn,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.12

Background: Colorectal cancer (CRC) is the most common gastrointestinal malignancy and is a significant cause of mortality. Its incidence is generally increasing in Asia. Reports from the West have indicated that the incidence of rectal cancer is increasing in the younger population. This study assessed the time trend of CRC in Brunei Darussalam specifically assessing the different age groups at which the incidences start to increase. Materials and Methods: The National Cancer registry was reviewed (1991 to 2014). The age standardized rate (ASR) and the age specific incidence rates (ASIRs) for three time periods (1991-1998), (1999-2006) and (2007-2014) were calculated. Results: The mean age of diagnosis was $59.3{\pm}14.6$ years old, incidences being slightly higher amongst men (57.6%) and Malays (67.1%). The most common tumor type was adenocarcinoma (96.4%). Rectal cancers accounted for 35.2% (n=372/1,056) of all cancers of the large bowel; more men were affected than women. The proportion of rectal cancer was also high among the indigenous group. In the three time periods, the ASR for CRC increased from 16 per 100,000 (1991-1998) to 19.6 per 100,000 (1999-2006) and 24.3 per 100,000 (2007-2014). The ASIRs for CRC increased markedly between the time periods 1998-2006 and 2007-2014, beginning in the 40-44 years age group. For rectal cancers, the ASIRs started to increase in the 25-29 age group onward whereas for colon cancers, the increase was observed at a later age, starting from the 45-49 age group. Conclusions: Our study showed an increase in the incidence of CRC including in the younger age groups. The increase was seen earlier in rectal cancer compared to colon cancer. These data mirror the trends reported from the West.

Rising Incidence of Primary Liver Cancer in Brunei Darussalam

Chong, Raymond Jih Yeong,Abdullah, Mohd Syafiq,Hossain, Mohammad Moshaddeque,Telisinghe, Pemasari Upali,Chong, Vui Heng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Background: Primary liver cancer (PLC) is the fifth most common malignancy worldwide and is still associated with high mortality. Hepatocellular carcinoma (HCC) and cholangiocarcinoma are the two most common PLCs, and their incidence varies across regions. Currently there are no published data available on the incidence of PLC in Brunei Darussalam. Materials and Methods: All proven PLCs between 2000 and 2009 were identified from the National Cancer Registry and reviewed. Metastatic diseases were excluded. A total of 123 cases (male 65.8%, female 34.2%) were identified and their data collected for calculation of the age standardised rate (ASR). Results: The most common type of PLC was HCC (87.8%) followed by cholangiocarcinoma (10.6%). There were two cases of hepatoblastoma. The mean age at diagnosis was 63.2 years. The overall ASR of PLC was 8.2/100,000, increasing from 4.5/100,000 population in 2000 to 11.4/100,000 population in 2009. The rates were higher among males (12.0/100,000) than females (4.7/100,000). Among the ethnic groups, Chinese had the highest rates (overall 13.1/100,000 with none recorded in 2000 to 30.3/100,000 in 2009) compared to the Malays (overall 8.5/100,000 increasing from 4.5/100,000 in 2000 to 12.3/100,000 in 2009) and the indigenous groups. The incidence increased after the age of 50 and was highest among the 75-79 age groups. Increase was seen for HCC but not for cholangiocarcinoma. Conclusions: The most common type of PLC is HCC and the annual incidence of PLC is increasing in Brunei Darussalam,rates being higher in males and Chinese.

Prevalence and Associated Factors of Diabetic Retinopathy among Type 2 Diabetes Mellitus Patients in Brunei Darussalam: A Cross-sectional Study

Sajid Adhi Raja,Vui Heng Chong,Noor A. Rahman,Lilabi M P Shakir,Joe Knights 대한안과학회 2022 Korean Journal of Ophthalmology Vol.36 No.1

Purpose: To determine the prevalence of diabetic retinopathy (DR) and the factors associated with retinopathy among type2 diabetes mellitus (DM) patients in Brunei Darussalam. Methods: Cross-sectional study of all type 2 DM patients who attended diabetic eye screening over a 3-month period at oneof four government hospitals. We assessed association between DR with the following variables: age, sex, glycated hemoglobin(HbA1c), duration of DM, hypertension, hyperlipidemia, and microalbuminuria. Results: There were 341 patients (female, 58.9%; mean age, 55.3 ± 11.9 years) with a mean duration of DM of 9.4 ± 7.4 yearsand mean serum HbA1c of 8.4% ± 1.9%. The overall prevalence of any DR was 22.6% (95% confidence interval, 18.8–27.1)with prevalence rates of 4.1% (95% confidence interval, 2.1–6.4) for proliferative DR and 9.7% (95% confidence interval,6.8–13.2) for vision-threatening DR. Multivariate analysis showed that DR was significantly associated with certain age groups(reduced in older age groups), longer duration of DM (11 years or more), poor control (HbA1c >9.0%) and presence of any microalbuminuria. Conclusions: DR affects one in five patients with DM in Brunei Darussalam, comparable to rates reported for other Asianpopulations. It is especially worrying that one in ten patients with DM had vision-threatening DR. DR was significantly associatedwith longer duration of DM, poor control and presence of microalbuminuria but reduced in older age groups. It isimportant to advocate good control right from the time of diagnosis of DM and institute timely and effective management ofretinopathy. DR was significantly associated with longer duration of DM, poor control of diabetes, and presence of microalbuminuriabut reduced in older age groups.