JOURNAL OF SCIENCE, Hue University, N 0 61, 2010 CANCER INCIDENCE IN THE POPULATION OF THUATHIEN HUE PROVINCE, VIETNAM, 2001-2009 Nguyen Dinh Tung Oncology Department of Hue Central Ho
Trang 1JOURNAL OF SCIENCE, Hue University, N 0 61, 2010
CANCER INCIDENCE IN THE POPULATION OF THUATHIEN HUE
PROVINCE, VIETNAM, 2001-2009
Nguyen Dinh Tung Oncology Department of Hue Central Hospital Lecturer of Hue College of Medicine & Pharmacy
SUMMARY
Hue Central Hospital is the place where the population-based cancer registry was carried out in Thua thien Hue Province The purpose of this research was to determine the cancer incidence in the community, to contribute to the assessment of cancer burden in the whole country and to analyse the epidemiology characters of some popular cancers in this area The active registering procedure has been performed, the data were collected from 14 hospitals and disposed of according to the international classification for oncology (ICD-O3) The data was stored in the CANREG software version 4 and was analyzed using EPI-INFO It was estimated that 7,324 new cancer cases were registered in the period 2001-2009, which included 55.54% and 44.46% males and females respectively The highest rate of cancer diseases belonged to Hue city (37.76%) There was 87.65% of cancer cases diagnosed by cytology or pathology The crude rate (CR) was 123.9, the age -standardized rate (ASR) was 173.5 per100,000 inhabitants; those in males and females were 95.3 and 103.9 respectively The cancers of liver, stomach, lung, oral cavity and non-Hodgkin lymphoma were the leading ones
in males Of these, the liver cancer rate is the highest (ARS 34.8).The leading cancers in females were breast, stomach, lung, liver and oral cavity; and the breast cancer rate is the highest (ARS 21.7) Cancer diseases have increased among inhabitants after the age of 40 years old in Thua thien Hue These increased more rapidly in males than in females and the age-specific rate was highest among the group of 70-75 years old
Key words: cancer incidence, Thua Thien Hue
1 Introduction
Vietnam is the second most populous country in South East Asia with 85 million people, and, it is also one of the poorest nations among developing countries in the world
There was not much information on the pattern of cancer incidence in Vietnam until recently Data was limited to the description of relative frequencies in hospitals (Luong and Pham, 1964; Luong, 1986, NB Duc 1990, NC Hung 1995) The Hanoi
Trang 2Cancer Registry (in the North of Vietnam) was founded in 1987 (Pham et al., 1993) In
1990, The Cancer Registry was set up in Ho Chi Minh City in the South of Vietnam to develop the hospital -based registry into a population -based cancer registry Apart from this, the Vietnam Cancer Society was also established in 1989 and one of its objectives was to improve the organization of cancer control activities
The Oncology Department of Hue Central hospital was set up in 1996 The main responsibilities of this department are to organize the cancer control program in the Middle and Highland areas of Vietnam, provide diagnosis, treatment as well as conduct scientific research on cancers Hue College of medicine and pharmacy and Hue Central Hospital are the training centers for medical staff for the whole region The Hue Cancer Registry was founded in 2000 to assess the cancer burden in Thua thien Hue province and data collection of cancer patients was gradually expanded in the Middle area of Vietnam
We present in this report the results from this population-based registry for the period of 9 years between January 2001 and December 2009 During this time, 7,234 new cases were recorded among residents of Thua Thien Hue Province These data are
of interest not only in providing a picture of the contemporary cancer profile in the Middle area of Vietnam, but also in permitting a comparison with incidence rates from the North and the South Regions of Vietnam
2 Methodology
Thua Thien Hue is a place with diverse cultural heritage Up to now, there is no place in Vietnam where so many originally historical vestiges have survived
as in Hue - the ancient capital city Hue is also one of the most important education centers in Vietnam In December 1993, Hue was approved to be a World Cultural Heritage Site by UNESCO
into 8 districts and 1 capital city (Hue) The estimated population in 2008 was about 1,119,800, comprising 89.9% of Vietnamese (Kinh) Other main ethnicities are Catu and Ta oi The climate is tropical, with high humidity and an average temperature of about 26°C It’s season of equatorial rains is between October and February
The population-based registry receives information from the Cancer Registry division of Hue Central Hospital, the Planning Division of Hue University Hospital, 3 private hospitals, 1 Military hospital and 08 district hospitals (among a total of 14 hospitals) The principal data sources are medical records, including outpatient records
if they exist, logs and reports of diagnostic laboratories (including all histopathology and cytology services in the city), and the patient logs from polyclinic departments Death certificates are not used as a source of information; since cause of death is very poorly specified (certification by a medical doctor is not required and is relatively rare,
Trang 3except for hospital deaths)
Any case with a permanent address in Thua thien Hue province which had a diagnosis of 'malignancy' made for the first time was registered This includes cases diagnosed by clinical diagnosis alone, even in out patient departments of district hospitals Although cancers and tumors without precise specification of whether they were benign or malignant (ICD-O behaviour codes /2 and /1) were registered, they were excluded from the analysis in this article - which included cases with tumors specified
as malignant or invasive (behaviour code /3) The date of occurrence of a case is defined
as the date of hospital admission or date of diagnosis The registry uses a computer with the CANREG 04 system for data entry and management, which provides a range of checks on validity of entered data
The population of this 8-district areas and Hue city in 2008 was taken to represent the population at risk The age-sex distribution of this population is shown in Table 5 Results are presented as numbers of cases by site, sex and age, with crude and age-standardized rates per 100,000 person-years
3 Results
Table 1 Number of cases by year and sex
Table 2 Number of cases by year and Address Code
Trang 49 Namdong 60 24 13 97 01.32
Table 3 Number of cases by Basis Diagnosis
Table 4 ICD-O Classification
Male Female Total
C00-C14
Lip, oral cavity , Nasopharynx &
Hypopharynx
C30-C39
Bronchus, lung &
other thoracic organs
C40,41,45-49
Bone, Connective,
Trang 5C60-C63 Prostate, Testis ,
Table 5.: Age Standard Population of Thua Thien Hue Province in 2008
Standard pop : World
Trang 6- - -
Table 6 Cancer incidence in Thua Thien Hue
Crude Rate
Age Standard Rate
Table 7 Ten of leading cancers in males
Cases
Crude Rate
ASR world
ICD ( 10 th )
Table 8 Ten of leading cancer in females
Cases
Crude Rate
ASR world
ICD ( 10
th )
Trang 76 Cervix 30 05.0 05.8 C53
Figure 1 Age - specific incidence rates : all sites, males and females
Figure 2 Age- specific incidence rate for Liver cancer
Trang 80 50 100 150 200 250 300
Females
Figure 3 Age-specific incidence rate for Stomach cancer
Figure 4 Age -specific incidence rate for Lung cancer
0 10 20 30 40 50 60 70 80 90
Breast
Cervix
Figure 5 Age-specific incidence rate for Breast & Cervix Cancer
Trang 94 Discussion
There were 7,324 cases specified as ‘‘malignant’’ [4,068 men (55.54%) and 3,256 women (44.46%)] in the 9 years period between 2001 and 2009 (table 1) The number of cases in 2008 and 2009 were higher than those in several years ago From this fact, we have received funding for this research in the period between 2001 and
2004 Since 2008, we have established the National Cancer Control Program in Thua Thien Hue province, including Cancer Registry
To estimate the cancer incidence within a year in Thua Thien Hue, we have chosen the year 2008 for representative data with 1,318 cases, including 745 men (56.52% ) and 573 women (43.48%) The crude rate (CR) was 123.9 per 100,000 and Age Standardized rate (ASR) was 173.5 per 100,000 for men; CR was 95.3 per 100,000 and ASR was 103.9 per 100,000 for women (table 1,5 & 6).The cancer registry in Hanoi (1990) has found 1975 cases specified as 'malignant' (1163 men and 812 women) in the 3-year period ( 1988-1990) The estimated rates of incidence for all cancers were 86.7 per 100,000 (CR) and 105.1 per 100,000 (ASR)for men; 59.0 per 100,000 (CR) and 63.6 per 100,000 (ASR) for women Additionally, the results from the population-based cancer registry in Ho Chi Minh City in the two year period between 1995 and 1996 provided the first information on the incidence of cancer in Southern Vietnam A total of 4,080 cancer cases in males and 4,338 in females were registered with CR as 89.0 per 100,000, ASR as 130.9 per 100,000 for men and CR as 85.8 per 100,000, ASR as 100.7 per 100,000 for women
Table 3 shows the most valid basis of diagnosis of the cases registered by tumor site Overall, 87,65% of cases have had some microscopic confirmation of the diagnosis, either histological or cytological and 3,65 % on the basis of clinical examination only The sites with the lowest percentages of morphologically were liver and lung cancer In
1988, the ability of cancer diagnosis in several cancer registries was: Hanoi 53,8%, Manila, Philippines 60,6%, and Khon Kean, Thailand 34, 5% The low histological verification in Khon Kaen is the result of very high rates of liver cancer in males but, in general, is not very different from other Asian registries
In men, lung cancer (18,52% of cases, ASR 34.8 per 100,000) was the most frequent malignancy, followed by cancer of the stomach (18,38% of cancers, ASR 31.3) Both showed a progressive increase of incidence with the maximum increase in the oldest age-group However, the liver cancer incidence was highest among the group between 60-64 years old (Figure 2&3) Lung cancer is the third highest in frequency ( 13.55% of cases, ASR 24.6), but for this tumor the average age of incidence is rather less, with the maximum rate in the age-group 70-74 and a decline thereafter (Figure 4) The fourth highest in frequency is cancer of the oral cavity and nasopharynx (ASR 11.5 ) and the fifth highest is non- Hodgkin lymphoma (ASR 7.5) In 2001-2004, the
Trang 10Hanoi cancer registry found that incidences of lung cancer (ASR 40.2), stomach cancer ( ASR 30.3) and liver cancer ( ASR 20.0 ) were very different from those from its cancer registry nearly 20 year ago ( ASR of lung 21.1, stomach 20.8, liver 14.0 )
In women, breast cancer is by far the most frequent malignancy (19,37% of cancers, an ASR of 21.7 per 100,000) Incidence rates increase to a maximum number among age group of 49-64, and then decline (Figure 5) Stomach cancer is the second highest in frequency (10,12 % of cancers, ASR 9.9), followed by lung cancer (6.8%, ASR 8.7)
Cervical cancer was formerly reported to be extremely common in Vietnam, particularly in the South (ASR 26.0 ) which, while similar to that observed elsewhere in South East Asia and the first cancer in women, it was 4 times greater than that in Hanoi, but it now declines to the second highest, following by breast cancer It now ranks the sixth in this report ( ASR 5.8 ), the fifth cancer in Hanoi in 2007 ( ASR 6.8 ) and the second cancer in HCM city in 2004 (ASR 16)
Cervical cancer is now generally thought to be related to infection with human Papillomavirus (HPV) especially HPV 16 and HPV 18 Cervical cancer incidence has decreased in the past 10 years This can be explained by the success of the cervical cancer screening program in the main cities of Vietnam Experiences from the cervix cancer screening program in US during the last 30 years has shown that PAP Smear can be useful for decreasing cervix cancer incidence, while mammography may just increase the ability of early detection for breast cancer
Breast cancer nowadays has become the leading cancer in Vietnam Research in Hanoi shown that ASR was 30.0 and 21.7 in this report This data was increased several times compare to 10 years ago ( ASR 14.0 and 9.1 ) Although breast cancer is the most common cancer in women, it is also several times lower when compare to US & Europe (ASR nearly 100 per 100,000) Thus the low rate currently observed may be associated with the reproductive factors accompanying previously high levels of fertility (early age
at first pregnancy, multiple births), low caloric intake (relatively late age at menarche, low body mass) and prolonged breast feeding of infants
5 Conclusions
The data on cancer incidence confirms the increase of crude rates and ASR among the population in Thua thien Hue during the last 10 years It also indicated a genuine risk for certain cancers, particularly those associated with 'western' lifestyles or consumption of alcohol and a certain relationship with some virus infection Cancers of the digestive organs was the most frequently seen cancer, followed by bronchus -lung cancer There was no difference, when compared with the whole country, in the incidence of breast cancer (the leading cancer in women) and cervical cancer is in the
Trang 11process of decreasing The difference, comparing with the North, is its higher incidence
of liver cancer and, comparing with the South, is its higher incidence of nasopharynx, stomach cancer and especially lower incidence of cervical cancer These findings provide useful clues for further etiological studies, as well as highlight current priorities for the cancer control program: hepatitis B vaccination, tobacco control, and early diagnosis and treatment of breast cancer
REFERENCES
1 GLOBACAN 2008: http://globocan.iarc.fr/factsheets/populations/factsheet
2 Duc Ba Nguyen: Vietnam National Cancer Control Program 2008-2010, Vietnam
Clinical Oncology, (09/2008) : 13-18
3 Duc Ba Nguyen: Cancer Incidence in Hanoi women in period of 1988-2007, Vietnam
Clinical Oncology, (09/2008) : 15-19
4 Hung Chan Nguyen: Action plan for cancer control in Ho Chi Minh City, HCM
Medicine Article, vol 12, N 4, (2008): 1-8
5 Tung Dinh Nguyen: Research on descriptive epidemiology in cancer disease in Thua thien Hue 2001-2004, Practice Medicine, 6/2006, (2006): 18-30
6 Anh Hoang Pham: Cancer in the population of Hanoi, Vietnam , 1988-1990, Br J
Cancer vol 68, (1993),: 1236-1243
7 Quoc Manh Nguyen: Cancer Incidence in Ho chi Minh City, Vietnam, 1995-1998, Int J
Cancer (1998) : Vol 76: 472-479