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Aim: To provide a comprehensive evaluation of the quality of the data at the Singapore Cancer Registry (SCR)., Methods: Quantitative and semi-quantitative methods were used to assess the comparability, completeness, accuracy and timeliness of data for the period of 1968-2013, with focus on the period 2008-2012., Results: The SCR coding and classification systems follow international standards. The overall completeness was estimated at 98.1% using the flow method and 97.5% using the capture-recapture method, for the period of 2008-2012. For the same period, 91.9% of the cases were morphologically verified (site-specific range: 40.4-100%) with 1.1% DCO cases. The under-reporting in 2011 and 2012 due to timely publication was estimated at 0.03% and 0.51% respectively., Conclusion: This review shows that the processes in place at the SCR yields data which are internationally comparable, relatively complete, valid, and timely, allowing for greater confidence in the use of quality data in the areas of cancer prevention, treatment and control., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In this review, we examine the trends in cancer incidence, mortality and survival in the last decade, using published data from the Singapore Cancer Registry in the period 1998 to 2009. While overall cancer incidences have remained stable, overall cancer mortality rates have declined for both genders. Thus, it is not surprising that there was an improvement in cancer survival. A steady decrease in lung cancer among males and females was observed, thereby leading to a drop in its cancer ranking. In the last five years, the most frequently occurring cancer was colorectal cancer among the male population and breast cancer among females. Survival for both cancers remained relatively optimistic. There is good reason to pay special attention to colorectal cancer due to its high frequency of occurrence among the Singapore population and because it is amenable to early detection via screening.

Objectives: We examined the association among cigarette smoking, smoking cessation and a broad range of cancer incidence and all cause and cause-specific mortality in a population-based cohort of adults of Chinese ethnicity in Singapore., Methods: Subjects were 61,320 participants of the Singapore Chinese Health Study (44.5% men, aged 45-74 years, recruitment from 1993-1998) who were free of cancer at the baseline examination. Main outcomes-of-interest included cancer incidence, all cause and cause-specific mortality as of December 31, 2005., Results: Cigarette smoking was positively associated with overall cancer incidence, including cancers at the following specific sites: head and neck region, upper gastrointestinal tract, hepatobiliary and pancreas cancer, lung, and bladder/renal pelvis cancer. Compared to never smokers, the relative risk (RR) (95% confidence interval [CI]) of cancer incidence (all cancer sites) among current smokers smoking >22 cigarettes/day was 1.9 (1.7-2.1), p-trend<0.0001. Similarly, cigarette smoking was associated with all cause and cause-specific mortality, including deaths due to cancer, ischemic heart disease, other heart diseases, and chronic obstructive pulmonary disease. Compared to never smokers, RR (95%CI) of all cause mortality among current smokers smoking >22 cigarettes/day was 1.8 (1.6-2.0), p-trend<0.0001. Also, relative to current smokers, ex-smokers experienced reduced cancer incidence and total mortality. The population attributable risk of smoking in men for cancer incidence as well as all-cause mortality was 23%, whereas in women it ranged from 4-5%., Conclusions: Cigarette smoking is an important risk factor for cancer incidence and major causes of mortality in Chinese men and women of Singapore.

Introduction: Inspection of trends in cancer incidence in ethnically or geographically diverse populations is important for the understanding of cancer patterns and also to provide clues for aetiologic studies. There is little information on cancer incidence among Malays, a low-risk population. The population-based cancer registration system in Singapore offers the opportunity in this regard., Materials and Methods: A review of all newly diagnosed cancer cases among Singapore Malay residents in the period 1968 to 1997 was conducted to determine the time trends using data from Singapore Cancer Registry. Age-standardised incidence rates and average annual percentage change, using Poisson regression, were calculated., Results: During the 30-year study period, a total of 9101 incident cases of cancer were diagnosed among Malays in Singapore. The 3 most common sites of cancer were lung, liver and colorectum in males; and breast, colorectum and ovary in females in the period 1983 to 1997. Leukaemia was among the top 10 cancer sites in both sexes. Malays generally experienced lower cancer incidence rates compared to Chinese, but rates have been increasing at 1.5% to 2% annually. Statistically significant increases in incidence were observed for most of the cancer sites. The incidence of nasopharyngeal carcinoma increased, while there were no significant changes in the general population., Conclusion: The relatively lower cancer risk among Singapore Malays might be attributed to genetic factors or closer adherence to a more traditional lifestyle. This study provides a baseline for comparisons with other populations with diverse cancer risk patterns in order to obtain a better understanding of possible aetiologic factors.

The age-standardised incidence rates for all cancers for 1998-1999 were 235.0 per 100,000 in males and 199.8 per 100,000 in females. The corresponding rates for 1993-1997 were 233.1 per 100,000 in males and 198.1 per 100,000 in females. The greatest difference was for breast cancer in females with age-standardised incidence rates increasing from 46.1 to 53.1 cases per 100,000 persons per year between these time periods. There also appears to be a shift of the peak age-specific incidence for breast cancer from premenopausal to postmenopausal years over this period. This suggests that our breast cancer incidence pattern is rapidly becoming more similar to populations in the West.

The Singapore Cancer Registry has provided comprehensive population-based incidence data since 1968. This paper describes the population-based survival analysis of the registry data. All invasive primary cancers diagnosed from January 1, 1968 to December 31, 1992 were passively followed up until December 31, 1997. Only 5.8% were lost to follow-up. Cumulative and observed survival rates were calculated using Hakulinen's method. Overall 5-year relative survival rates have increased dramatically over the 25-year period in both genders. Significant increases are seen with nasopharynx, stomach and colo-rectum cancers, non-Hodgkin's lymphoma, leukemias and cancers of the testis, cervix, ovaries and breast. When compared with the Surveillance, Epidemiology and End Results (SEER) rates in the United States, the 5-year relative survival rates in Singapore are generally lower. However, the rate of change between the two countries is fairly similar. On the average, the rates are 10 to 15 years behind the SEER rates and 5 to 10 years behind Finland, Switzerland and Japan, but they are close to the UK rates. The age-standardized 5-year survival rate for Singapore is higher for most sites compared with other developing countries like Qidong (China), Madras (India), Bombay (India) and Chiang Mai (Thailand). The 25-year trend in cancer survival in Singapore showed two extreme groups: those showing no change and those showing significant improvements. Reducing the incidence of cancers belonging to the first group remains the only viable mode of cancer control. For cancers in the second group, improvement in survival is due to a combination of successful early detection measures and effective treatment services in Singapore., (Copyright 2001 Wiley-Liss, Inc.)

The rapidly evolving field of molecular epidemiology represents a paradigm shift in medical research, illustrating the convergence of basic, clinical and epidemiologic research, as well as the application of laboratory methods to population studies. As a complement and improvement to traditional epidemiologic approaches, the use of biomarkers offers more accurate exposure assessment at an individual level, better understanding of the biological mechanism of carcinogenesis by tracking a continuum of events between exposure and disease, as well as the ability to discern host or genetic factors that may account for variations in cancer susceptibility among individuals or ethnic populations. Further, biomarkers have also proved useful in cancer diagnosis and prognosis. This article attempts to review the latest progress in molecular cancer epidemiology and to summarise the current state of research in Singapore.

The idea that diet and nutrition have an important influence on health is an age-old one. Its link with cancer was mentioned in Chinese medical writings in the twelfth century. Recent interest in this subject started in the 1930s with animal studies. Today, the notion that diet has an aetiological role in cancer is well accepted. Some of the methodological issues in human studies include the inherent difficulty in estimating dietary intakes, the effect of confounding and interaction, and the low risks associated with specific food items or nutrients. The paper will discuss the main factors implicated, with particular reference to studies in Singapore--on colorectal and breast cancers. The findings point to the profiling of a high-risk diet comprising high meat intake and a relative deficiency in fruits and vegetables (especially those of the cruciferae family). The active components of fruits and vegetables point to a number of micronutrients and substances which have cancer inhibitory properties. They are currently subjects of vigorous research all over the world.

In the development of a national cancer control programme, the cancer registry can play a pivotal role by providing useful data for planning and evaluation of curative and preventive services. Having produced information on cancer incidence patterns, the Singapore registry is now able to analyse incidence trends among the Chinese population based on the first 15 years of data (1968-1982). Increases in incidence are reported for all sites (at average annual rate of 0.4%), lung (2.2%), colon (3.0%), rectum (3.1%), skin (3.2%), prostate (4.9%) and bladder (2.3%) in males; for all sites (1.3%), lung (2.4%), colon (5.0%), rectum (4.1%), skin (3.9%), breast (3.2%) and ovary (3.4%) in females. Marked decreases are reported for oesophagus (3.9% in males, 5.8% in females) and stomach (2.2%) in males and 1.4% in females). No significant changes are seen in nasopharynx, liver (both sexes) and cervix. Some of the associated changes in risk factor prevalence are discussed in relation to the main cancer sites.

In Singapore, cancer incidence is documented separately for the different Chinese dialect groups, as a means of providing a possible insight into environmental or genetic factors which may be involved in the aetiological process. Thus, it would be useful to determine whether or not the Chinese population in Singapore still comprises distinct dialect groups. In view of this, an investigation into the dialect group of the parents of 792 hospital in-patients (cases and controls) was carried out. It was found that the vast majority of patients (94.2%), most of whom were born before 1940, had parents of the same dialect group. The percentages of within-dialect marriages were only slightly less for offspring born in Singapore or Malaysia as opposed to China, and decreases with time were small. Thus in 1985-87 Chinese cancer patients and controls in Singapore, of the ages represented in this study may indeed be classified according to their father's dialect and this is likely to be the case for at least the next decade or so. This finding will be of use to cancer epidemiologists as well as others studying Chinese dialect group variations in disease patterns.

Population-based registration of all cancer cases diagnosed in Singapore began in 1968. While most of the basic demographic and clinical data collected are reasonably adequate and accurate, the item on occupation is quite unsatisfactory. Most notifying practitioners either do not state the patient's occupation or use general terms that do not indicate any particular environmental exposure. In spite of the difficulties, some notifications do contain specific information on the occupation. For the period 1968-1977, analyses on cancer incidence in occupational groups were confined to Chinese males aged 35-64. Due to the lack of relevant population data, relative risks were based on the Standardised Relative Proportional Risk (SRPR), standardised for age, dialect group and place of birth. Managers and clerical workers seem to have high SRPRs for cancer of the large bowel, but low SRPRs for cancer of the lung and oesophagus. High SRPRs for lung and oesophagus are seen in some groups of manual workers (e.g., bricklayers, carpenters, transport equipment operators and labourers not otherwise specified). There is also a high SRPR for skin cancer among farmers.

The Singapore Cancer Registry started operations on January 1, 1968. It is a population-based registry that seeks to obtain basic epidemiological and clinical data on all cases of cancer diagnosed in Singapore. The results presented pertain only to Singapore citizens and permanent residents and cover the period from 1973 to 1977. Of special interest are the cancer patterns of the main ethnic groups in Singapore. Generally, the Chinese (76% of total population) have significantly higher risks for cancer; the most prevalent sites are the nasopharynx, esophagus, stomach, liver, and lung. Within the Chinese group are also dialect group differences. The Malays (15% of population) have the lowest rates for most sites, whereas among the Indians (7% of population), mouth cancer is an important site for both sexes. All these variations provide useful clues in the search for etiological factors.

Since the inception of cancer registration in Singapore in 1968, the incidence rates of malignancies have been monitored among the 3 major ethnic groups--Chinese (77% of population), Malays (15%) and Indians (6%). Substantial changes in incidence at various sites were observed in the period 1968-1982, which seem to represent a shift from the pattern of cancer incidence in China towards that prevailing in the West. We now report on the Singapore Chinese experience, in which the following changes were notable: decreases in rates of cancers of the stomach and oesophagus and increases in rates of cancers of the lung, colon, rectum, skin (excluding melanoma), breast and ovary. For several sites, the secular changes differed among age groups; among women under 50 years of age breast cancer increased particularly sharply and lung cancer decreased. Environmental and personal factors, potentially responsible for the change, are discussed.