Survival of Stomach Cancer Cases in Khon Kaen,Thailand 2000-2012

Background: Stomach cancer is an aggressive malignancy that is difficult to detect at an early stage and therefore is characterized by poor survival rates. Over the last two decades, there has been no report of gastric cancer survival in Khon Kaen province, Thailand. The aim of this retrospective cohort study was to provide up-to-date information about the survival of gastric cancer patients in this province. Materials and Methods: Data from Khon Kaen population-based cancer registry, Faculty of Medicine, Khon Kaen University were newly obtained on 650 patients who were diagnosed with stomach cancer during the period 1 January, 2000 to 31 December, 2012. These were then followed up until death or the end of the study (31 December 2014). We calculated the observed survival with the actuarial life table method, and relative survival, defined as the ratio of observed survival in the group of the stomach cancer patients to the expected survival in the entire Thai population from the estimated generation life tables for Thailand of five-year birth cohorts from 1900 - 2000. Results: The 5 year observed and 5 year relative survival rates were 17.2 % (95% CI: 13.54-21.14) and 18.2 % (95% CI: 14.3-22.4), respectively. The highest 5 year relative survival rates were demonstrated among patients aged 45-65, with stage I or II lesions, with adenocarcinomas, with a body of stomach location, well differentiated and receiving surgery and/or chemotherapy. Conclusions: The observed and relative survival rates were close to each other. Our findings provide basic information beneficial to development of an effective treatment system and appropriately improved population-based cancer registration.     

Loss-adjusted survival of cervix cancer in Khon Kaen, Northeast Thailand

For incident cancers of the cervix uteri (601 cases) registered in the population-based cancer registry of Khon Kaen province, Northeast Thailand, in 1985-1990 loss-adjusted survival probabilities were estimated by a logistic regression model with four prognostic factors (age at diagnosis, stage of disease, place of residence and treatment), and compared with observed survival, estimated by the actuarial method. All patients were followed up for a minimum of 5 years, using both passive and active methods. In all, 27.6% of patients were lost to follow-up within 5 years of the index date. The overall observed survival at 5 years was 56.8% and loss-adjusted survival was 54.7%. The difference between the loss-adjusted and observed survival at 5 years was small: 2.1% overall, varying between 0.8 and 3.5 percent units for any prognostic group. The assumption of independence of loss to follow-up and death in the calculation of survival by the actuarial method in this, and probably in other, population-based series, is reasonable and leads to no material bias in the estimates.     

Cancer survival in Khon Kaen, Thailand, 1993-1997

The Khon Kaen cancer registry was established in 1984 as a hospital-based cancer registry, and population-based cancer registration started in 1988 with retrospective data collection from 1985. Cancer registration is done by passive and active methods. Data on survival for 13 cancer sites or types registered during 1993-1997 were reported. Follow-up was done by active methods, with median follow-up ranging between 8-32 months for different cancers. The proportion with histologically verified diagnosis for various cancers ranged between 54-100%; death certificates only (DCOs) comprised 0-5%; 85-97% of total registered cases were included for survival analysis. Five-year follow-up ranged from 40-83%. Five-year age-standardized relative survival rates for common cancers were cervix (58%), breast (61%), colon (39%), ovary (43%), non-Hodgkin lymphoma (42%) and rectum (43%). Five-year relative survival by age group portrayed an inverse relationship or was fluctuating. Five-year survival was the highest for localized disease, followed by the regional and distant metastasis categories. Trends in 5-year relative survival in 1993-1997 compared to 1985-1992 showed a marked increase for cancers of the rectum, breast, ovary, Hodgkin and non-Hodgkin lymphomas and decrease for cancers of the lip and larynx.     

Cancer Incidence in Thailand, 1995-1997

There are five population-based cancer registries in Thailand in different regions of the country. Four of them ‍(Chiang Mai, Khon Kaen, Bangkok, and Songkhla) have been operating since 1988 and the other (Lampang) since ‍the early 1990’s. These registries have published regular 3-year cancer incidence reports since the first in 1993 for ‍the period 1989-1991. The objective of this article is to summarize the figures of cancer incidence in Thailand during ‍1995-1997. The population of Thailand in 1996, at the middle of the period, was 27 million males and 27.5 million ‍females. Information of cancer cases residing in the five provinces was collected and abstracted from different ‍sources. Age-standardized incidence rate (ASR) of cancer in males and females was calculated for each registry and ‍that for the whole country was estimated using the five registries as representatives for the four geographical regions ‍of Thailand. The estimated number of new cancer cases in 1996 for the whole country was 35,539 men and 38,476 ‍women and the ASRs were 149.2 and 125.0 per 105 population in men and women respectively. Cancer incidences ‍greatly differed from region to region. Lung cancer was the commonest in Chiang Mai and Lampang in the Northern ‍region in both sexes. The incidence of liver cancer in Khon Kaen in the Northeastern region outnumbered all the ‍others in both sexes; cholangiocarcinoma was the major type of liver cancer. In Bangkok, lung cancer was the most ‍important cancer in males and breast cancer was in females. Though it was lung and cervix uteri cancer that ranked ‍the first in men and women in Songkhla, the rate of oral and pharyngeal cancer was exceptionally higher than in ‍other registries. The geographical variability in cancer patterns in Thailand reflects exposure of the population to ‍different risk factors unique to the different regions. In the study as a whole, there are some methodological weak ‍points in estimating the ASRs and number of cancer cases for the whole country, but the results are the most reliable ‍cancer statistics from Thailand at the moment. In conclusion, both a country-wide and region-specific cancer control ‍programmes are needed for Thailand. The national one would be for the cancers common to all regions, and the ‍provincial-level emphasis should be on cancers which are the major problems in the area.     

Numbers of New Cases and Trends of Cancer 1993-2012: Srinagarind Hospital Based Population,Khon Kaen,North-East Thailand

Background: Cancer is the most common cause of death in Thailand, where treatment outcomes andprognosis are poor and mortality rates remain high. This study reports new cancer cases and trends of allcancers registered in Srinagarind Hospital from 1993 to 2012 and also provides a picture of the cancer situationin Northeast Thailand. Materials and Methods: All new cases of cancer registered in the hospital-based cancerregistry at Faculty of Medicine, Srinagarind Hospital, Khon Kaen University during 1993-2012 were included inthe study. Results and Conclusions: The number of new cancer cases has gradually increased each year duringthe last 20 years. The three most common cancers at present in males are liver and bile duct cancer, lung cancerand colorectal cancer, respectively. In females, liver and bile duct, breast and thyroid cancers are now the mostfrequent. Interestingly, the number of cases of both liver and bile duct cancer and colorectal cancer in malesnoticeably increased during the second decade of the study. Additionally, breast cancer greatly increased in thesame decade and lung cancer in females climbed into the top five most common cancers. Thyroid cancer hasalso risen steadily in the last decade. Trends of common cancers are similar to those throughout Thailand.     

Comparing Survival of Oral Cancer Patients Before and After Launching of the Universal Coverage Scheme in Thailand

Background: As the treatment modalities for oral cancer have been relatively consistent during the last two decades, this study was conducted to compare survivals of oral cancer patients in Khon Kaen Province before and after the universal coverage scheme (UC) was launched in Thailand. Materials and Methods: The data were retrieved from the populationbased cancer registry of Khon Kaen for oral cancer patients diagnosed during 19922001 (preUC), and 20042012 (postUC). To compare survival of the two cohorts, Kaplan Meier and log rank tests were employed. Results: Of 1,196 patients, 65% were females and the median age was 65 years. The most common primary sites were lip (31.0%), tongue (29.9%), and buccal mucosa (14.6%). The proportion of early stage cancer increased from 20.4 % in preUC to 41.3% in postUC. The overall 5year survival rate was 36.5% (95% CI 32.640.9) for preUC and 32.4% (95% CI 28.836.4) for postUC. The declining survival was mainly due to an increasing proportion of tongue cancer. However, no survival improvement was demonstrated on subgroup analysis of the tongue cancer patients. Conclusions: After the universal coverage scheme had been launched, early diagnosis increased, but no significant gain in survival for oral cancer patients was achieved.     

Cervix Cancer in Khon Kaen,Northeast Thailand, 1985-1999

The incidence of cancer of the cervix uteri in Khon Kaen Province is moderately high (age-standardised rate 16.8 ‍per 100 000 person-years), with about a two-fold variation in incidence between different districts. Stage at presentation ‍is considerably more advanced than in the United States and Europe, and there has been little change in incidence ‍over the last 15 years. Currently, control of cervix cancer is through early detection and treatment. Screening ‍programmes have, to date, been opportunistic, but a new national plan anticipates that all women will be screened ‍six times during their lifetime. The results from Khon Kaen provide a benchmark against which the success of this ‍policy can be evaluated.     

Incidences,Trends and Long Term Outcomes of Retinoblastoma in Three Cancer Registries,Thailand

Background: Retinoblastoma (RB) is rare, albeit the most common primary intraocular malignancy amongchildren. To elucidate the true incidence, trend and survival, we studied incidences and trends of retinoblastomain a large population with long-term follow-up using data from 3 population-based cancer registries. Objective:To describe the incidence, trends and survival of RB between 1990 and 2009 in Khon Kaen, Songkhla and ChiangMai, Thailand. Materials and Methods: We sourced the data from the cancer registries in Khon Kaen, Songkhlaand Chiang Mai on children with retinoblastoma, diagnosed between 1990 and 2009. Retinoblastoma was definedas per the International Classification of Disease for Oncology version 3 using the code 9510/3. Incidence wasanalyzed using the standard method with the criteria of the International Association of Cancer Registries. TheKaplan-Meier method was applied to calculate cumulative survival. Trends were calculated using the log ranktest. Results: We identified 75 cases of children between 0 and 15 years of age diagnosed with RB (Khon Kaen31, Chiang Mai 20, Songkhla 24). Males and females were equally affected. The most common age group was0-4 years. The morphological verification of the disease was 90.7%. The respective ASR in Khon Kaen, ChiangMai and Songkhla was 4.4, 4.0 and 4.6 per million; for which the overall ASR for all 3 areas was 4.3 per million.The respective trend in incidence was 4, 2.8, 5.8 and 5.4 during 1990-4, 1995-9, 2000-4 and 2005-9. Overall,incidence trended gradually upward by 2% annually. The respective survival rate in Khon Kaen, Chiang Maiand Songkhla was 50, 40 and 75% (differences not significantly different at p=0.14) and the overall survival forall centers was 60%. Conclusions: Over the last two decades, the incidence and overall survival of retinoblastomahas increased. The ASRs and survival in Thailand were less than those in resource-rich countries.     

Epidemiology of oral and pharyngeal cancers in Khon Kaen, Thailand: a high incidence in females

Background: This study was aimed to describe incidence, trends, and survival of oral and pharyngeal cancers in Khon Kaen, the province situated in the northeast of Thai-land. Methods: Data on oral and pharyngeal cancer cases diagnosed during 1985 - 2001 were retrieved from the population-based cancer registry of Khon Kaen. The final status of the patients was verified by database linkage and follow-up using postcards. Results: Of 1,038 cases, 62.6% were female and 37.4% were male, with a mean age of 63 years. The age-standardized incidence rate (ASR) in females (6.2 per 100 000; 95%CI 5.7-6.7) was significantly higher than in males (3.9 per 100 000; 95%CI 3.5-4.4). Annual percent changes in ASR were 1.7 in females (p<0.05), but 1.2 in males. Lip and buccal cancers were the most common sites respectively; however, the incidence of tongue cancer was increasing in the last period. Eighty five percent of all cases were diagnosed in advanced stage (stage III and IV). The overall five-year relative survival was 43.1%. We found stage distribution and survival did not change during the study period. Conclusion: The considerably high incidence in female suggests a need for research on specific risk factors. Moreover, attempts should be made to detect oral cancers earlier in order to improve the outcomes of cancer control.     

Hospital-based Population of Elderly Cancer Cases in Northeastern Thailand

Background: The proportion of aged Thais (≥65 years old) is expected to be 30% by 2030, leading to an increased number of elderly cancer cases. Older individuals have distinct patterns of cancer and treatment needs. We therefore conducted the present study of new cancer cases and trends to get a perspective on the elderly cancer situation in Northeast Thailand. Materials and Methods: All new elderly cancer cases (≥65 years) registered in the hospital-based cancer registry at the Faculty of Medicine, Srinagarind Hospital, Khon Kaen University during 1993-2012 were included in the study. Results: Elderly patients accounted for 31.6% of all cancer patients and new cancer cases in the older age group increased 46% from the first to second decades. The absolute number of oldest old (80+ years) doubled. The top three cancers in males were liver and bile duct, lung, and colorectal. In females, the three most common cancers were liver and bile duct, oral cavity, and cervix. Cancers with the highest percentages of increase were thyroid, prostate, and colorectal. Conclusions: Elderly cancer cases are increasing. Treatment modalities and palliative care for older populations are urgently needed.     

Cancer Incidence Trends in Thailand , 1989-2000

Through 2004, five cancer registries in Thailand have collected data for more than ten years. Three-year cancerincidence in Thailand covering the years 1989-1997 has been regularly reported in three volumes of ‘Cancer inThailand’. Since the data for the last decade of the 20th century have been collected, the trends in incidence of somecancer sites were analyzed. Data sources were registry data from Chiang Mai, Lampang, Khon Kaen, Bangkok, andSongkhla, which are representative of the four major geographic regions of Thailand. The data drawn in 2002covered the years 1989 to 1997 for Bangkok, the other four registries drew data from 1989 to 2000. The populationdenominators were estimated from the two censuses in 1990 and 2000. Only cancers of the liver, lung, colon-rectum,female breast, uterine cervix, and all cancer sites were analyzed since cancers of these sites may have major publichealth impacts. Age-specific incidence rates of different 5-year age groups were projected through the period 2007-2009 using a linear regression model if the rates were increasing, and a log-linear model to prevent prediction of anegative rate if the rates were decreasing. During the past decade, colorectal and breast cancers showed a statisticalsignificant increasing trend, while the trend was generally stable for cancer of other sites. The number of new cancercases of all sites is expected to be approximately 125,000 by the year 2008, compared with 81,000 in 1999. However,the accuracy of projections depends very much on the quality of the cancer registries’ data. The Bangkok registrysignificantly improved case ascertainment in recent years, while the Chiang Mai registry had a consistent drop inincidence of cancer at many sites. In-depth investigation of some cancer sites and age period cohort modeling arerequired for better understanding of cancer trends in Thailand.     

Opisthorchis viverrini Infection Among People in the Border Areas of Three Provinces,Northeast of Thailand

Opisthorchis viverrini is still a serious problem in Northeastern and Northern Thailand. Active surveillance is required to determine updated data for further prevention and control planning. Therefore, this study aimed to examine the prevalence and risk factors for O. viverrini in three provinces, Northeastern Thailand. A cross-sectional survey was conducted during October 2015 to March 2016 at Kaeng Sanam Nang district of Nakhon Ratchasima province, Waeng Noi district of Khon Kaen province, and Khon Sawan district of Chaiyaphum province, Thailand. Stool samples were examined by using a modified Kato-Katz Thick smear technique. From a total of 978 participants screened, O. viverrini infection was found in 1.74%, the majority opf positive cases being male (6.62%), age group 51-60 years old (4.21%), educated at primary school (8.43%), occupied with agriculture (9.62%),having an income <4,000 baht per month (4.82%), and living in Khon Sawan district (8.43%). Participants had a high knowledge level (42.43%), good attitude level (34.76%), and fair level (38.04%). The present study indicates the O. viverrini infection rate is low, but elderly males with primary school education involved in agriculture are still frequently effected particularly in Khon Sawan district. Therefore, this risk g roup requires behavior modification and continued monitoring.     

Survival of Cancer Patients with Co-Morbid Tuberculosis in Thailand

Background and objective: We aimed to investigate the survival time and its related factors among cancer patients with co-morbid tuberculosis (TB) in Thailand. Methods: We conducted this retro-prospective cohort study on cancer patients without co-morbid TB using the data from population–based cancer registry of Khon Kaen, TB databases from the Khon Kaen Central Hospital, and the Region 7 Office of Disease Prevention and Control from 2001 to 2015 to determine the onset of TB after cancer. The cancer patients were then followed up until 2017 to assess their survival status. The Kaplan-Meier method, log-rank test, and Cox proportional hazard regression were used to estimate cumulative survival curves, compare various survival distributions, and adjusted hazard ratios. Results: Lung, head and neck, and liver cancers led to a  significantly different survival time between patients with and without co-morbid TB. After adjustment, it was found that patients suffering from lung, head and neck, or liver cancer and co-morbid TB had significantly lower risk of death than those without co-morbid TB. Based on the stratified analysis, lung cancer patients with distant metastasis and co-morbid TB had 3.01-fold and 2.99-fold significantly increased risk of death compared to those without co-morbid TB. Conclusion: We found that cancer patients with co-morbid TB were at lower risk of death compared with those without co-morbid TB. In addition to cancer stage, it seems that cancer comorbidity with TB could modify the risk of death for lung cancer patients.There is a need for further studies to support our findings including other related risk factors.     

Cervical Cancer in Khon Kaen,Thailand: Analysis of 1990-2014 Incidence Data and Prediction of Future Trends

Background: Cervical cancer is the second most common cancer of women in Thailand. There have been no reportsof incidence and future in Khon Kaen, a province in northeastern Thailand, where the relatively high prevalence givesevaluation of cervical cancer screening a high priority. Objectives: To determine cervical cancer incidence rates inKhon Kaen for 1990–2014 and predict future trends until 2029. Methods: Cancer incidence data from the Khon Kaenpopulation-based cancer registry were analyzed and age-standardized incidence rates (ASR) were estimated. Joinpointanalysis and age-period-cohort modeling were applied for data from 1990 to 2014 and the Nordpred package wasemployed to project trends from 2015 to 2029. Results: Between 1990 and 2014, a total of 3,258 cases were diagnosedwith ICD-O code C53 (invasive cervical cancer). Before 2005, an annual percentage change (APC) varied widely, withoutliers in 1993 and 1999. The APC computed with the Joinpoint software decreased at -2.8% (95% CI;-4.5 to -1.1)per year on average. After 2005, a rise was noted until 2008, after which a drop became apparent with an APC of-8.0% (95% CI; -14.5 to -1.1) per year on average. Both period and cohort effects played a role in shaping the decreasein incidence. The three projection method suggested that incidence rates would continue to decrease in the future.Conclusions: A decreasing trend in incidence of cervical cancer in Khon Kaen was noted from 1990 to 2014 with aprediction of continuous decrease until 2029. Maintenance and improvement of the screening program is advised.     

Trends in Survival of Childhood Cancers in a University Hospital,Northeast Thailand, 19932012

Background: In Thailand, a national treatment protocol for childhood leukemia and lymphoma (LL) was implemented in 2006. Access to treatment has also improved with the National Health Security system. Since these innovations, survival of childhood LL has not been fully described. Materials and Methods: Trends and survival of children under 15 with childhood cancers diagnosed between 1993 and 2012 were investigated using the hospitalbased data from the Khon Kaen Cancer Registry, Srinagarind Hospital, Faculty of Medicine, Khon Kaen University, Thailand. Childhood cancers were classified into 12 diagnostic groups, according to the ICCC based on the histology of the cancer. Survival rates were described by period, depending on the treatment protocol. For leukemias and lymphomas, survival was assessed for 3 periods (199399, 20005, 200612) while for solid tumors it was for 2 periods (before and after 2000). The impacts of sex, age, use of the national protocol, and catchment area on leukemia and lymphoma were evaluated. Overall survival was calculated using the KaplanMeier method while the Cox proportional hazard model was used for multivariate analysis. Trends were calculated using the R program. Results: A total of 2,343 childhood cancer cases were included. Survival for acute lymphoblastic leukemia (ALL) from 19939, 20005, and 200612 improved significantly (43.7%, 64.6%, and 69.9%). This was to a lesser extent true for acute nonlymphoblastic leukemia (ANLL) (28.1%, 42.0%, and 42.2%). Survival of nonHodgkin lymphoma (NHL) also improved significantly (44%, 65.5%, and 86.8%) but not for Hodgkin disease (HD) (30.1%, 66.1%, and 70.6%). According to multivariate analysis, significant risk factors associated with poor survival in the ALL group were age under 1 and over 10 years, while not using the national protocol had hazard ratios (HR) of 1.6, 1.3, and 2.3 respectively. In NHL, only nonuse of national protocols was a risk factor (HR 3.9). In ANLL and HD, none of the factors influenced survival. Survival of solid tumors (liver tumors, retinoblastomas) were significantly increased compared to after and before 2000 while survival for CNS tumors, neuroblastoma and bone tumors was not changed. Conclusions: The survival of childhood cancer in Thailand has markedly improved. Since implementation of national protocols, this is particularly the case for ALL and NHL. These results may be generalizable for the whole country.     

Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Cancer Risk in a Nested Case-Control Study in North-East Thailand

Cervical cancer continues to be an important public health problem in Thailand. While the high risk humanpapillomavirus (HPV) types have been established as the principle causative agent of both malignancies andthe precursor lesions, cervical intraepithelial neoplasia (CIN), other factors may also be involved like othersexually transmitted diseases, as well as smoking. Chlamydia trachomatis is an obligate intracellular Gramnegativebacterium which has a tendency to cause chronic infection featuring inflammation and therefore mightbe expected to increase the risk of cervical cancer. In the present nested case-control study, 61 cases of cervicalcancer and 288 matched controls with original serum samples were identified from the Khon Kaen Cohort,established in the North-East of Thailand, by linkage to the Khon Kaen population based cancer registry. C.trachomatis specific IgG antibodies at recruitment were measured by microimmunofluorescence and assessed forassociation with cervical cancer using STATA release10. No significant link was noted either with all cancers orafter removal of adenocarcinomas. The results suggest no association between Chlamydia infection and cervicalcancer development in North-East Thailand, but possible influencing factors must be considered in any futureresearch on this topic.     

Ultrasound Screening for Opisthorchis viverrini-associated Cholangiocarcinomas: Experience in an Endemic Area

In Thailand, liver cancer is the most common malignancy in males and the third most common among females. Inthe Northeast region, cholangiocarcinoma (CHCA) is the prevalent type, with Opisthorchis viverrini (OV), an endemicliver fluke, being considered the cause. We evaluated the role of ultrasound (U/S) for cholangiocarcinoma screeningas part of a larger cohort to characterize the linkage between liver fluke infestation and CHCA in Khon Kaen(Northeast Thailand). Most people (77%) had normal U/S findings while only 0.5% had suspected CHCA; thus, U/S should be used primarily for those with the highest risk, presenting symptoms and/or being OV positive.     

The Coverage of Cervical Cancer Screening in Khon Kaen,Northeast

Cervical cancer is a common cancer in Thai women and one of the only cancers that can be readily cured if early ‍detection is successful. The Pap smear is an accepted as an appropriate means for cervical cancer screening at ‍present. However, there are still some management problems with early detection programmes. Since data showing ‍how many women have been screened by Pap smear are limited in Thailand, the present study was conducted with ‍the aim of determining coverage in a defined population in the sample area, Thakaserm sub- district in Nampong ‍district, Khon Kaen province, Thailand. The investigation was carried out during June-August 2000 to collect ‍information on history of screening for cervical cancer using questionnaires. All women aged 20 and above were ‍asked to answer the set of questionnaires a total of 1,199 women responded. There were 66.9% that reported having ‍received a Pap smear test for screening for cervical cancer at least once. However, there were 33.1 % that had never ‍undergone a Pap smear in their life. It is important to find a strategy to increase the coverage of cervical cancer ‍screening programme for this population. ‍     

Trends in incidence of hepatocellular carcinoma, 1990-2009, Khon Kaen, Thailand

Background: Liver cancer is the most frequent cancer among Thais especially people in northeastern Thailand, but there has as yet been no assessment of trend. The data of all cancers in Khon Kaen can be retrieved from data base of the Khon Kaen Cancer Registry (KKCR) which was established in 1984. Objective: To assess the incidence trend of hepatocellular carcinoma in Khon Kaen, Thailand, between 1990 and 2009. Methods: Population-based cases of liver cancer registered between 1985 and 2009 were retrieved from the KKCR data base and cases with diagnosis of hepatocellular carcinoma (HCC) with the coding C22.0 according to ICD-O were selected. Incidence trends were calculated using the Jointpoint analysis. Results: There were 7,859 cases of HCC during the study period. Males were affected two times more frequently than females. The most common age group of cases was 50 and 69 years (60.3%). Most patients were diagnosed based on radiology imaging (40.6%) while the morphology verification was 7%. The age-standardized rates (ASR) were 13.1 to 49.8 per 100,000 among males and 4.8 to 38.4 per 100,000 among females depending on year of diagnosis since 1985. Remarkably, the ASRs were clearly low during first few years of starting the registration. The overall ASRs of HCC were 30.3 per 100,000 in males (95% CI: 25.9 to 34.6) and 13.1 per 100,000 (95% CI: 10.4 to 15.8) in females. During 1990-2009, the trends in incidences have been decreasing significantly with the annual percent change (APC) of 6.2% per year (95% CI: –7.6 to –4.8) in males and by 6.5% per year in females (95% CI: –8.4 to –4.9). Conclusions: The incidence trends have been decreasing in both sexes. The recent decline in incidence may represent a falling risk.