Trends in the Incidence of Kaposi's Sarcoma and Non-Hodgkin Lymphoma in Northern Thailand during the Time Period of Universal Access to Antiretroviral Treatment, 1998-2017.

PURPOSE: We evaluated the trends in incidence of Kaposi's sarcoma (KS) and Non-Hodgkin's lymphoma (NHL)  over the two decades in northern Thailand during which access to antiretroviral treatments (ART) in Thailand was scaled up. METHODS: This is retrospective observational study. Data from 1998 to 2017 of patients diagnosed with KS and NHL from three long-standing, population-based cancer registries in northern Thailand (Chiang Mai, Lampang and Lamphun) were used to describe trends in age-adjusted incidence rate (ASR) of these cancers. The annual percent change (APC) of incidence rates were evaluated over this timeframe. RESULTS: The incidence of KS significantly increased from 1998 to 2017 in males (APC of 6.9%) and very low incidence for evaluating change in female. NHL incidence significantly increased from 1998 to 2017, 2.2% and 1.8% per year in males and females, respectively (p<0.001). CONCLUSION: In the last two decades, the incidence of KS in male and NHL in both sexes have increased in northern Thailand, while the incidence of KS in female remained low. The change in incidences in opposite to the decline in HIV prevalence and increase ART coverage rate supported that other associated factors attributable to the development of KS and NHL should be looked for i.e., environmental, occupational exposures and other infections.

External Validation of the Individualized Prediction of Breast Cancer Survival (IPBS) Model for Estimating Survival after Surgery for Patients with Breast Cancer in Northern Thailand.

The individualized prediction of breast cancer survival (IPBS) model was recently developed. Although the model showed acceptable performance during derivation, its external performance remained unknown. This study aimed to validate the IPBS model using the data of breast cancer patients in Northern Thailand. An external validation study was conducted based on female patients with breast cancer who underwent surgery at Maharaj Nakorn Chiang Mai hospital from 2005 to 2015. Data on IPBS predictors were collected. The endpoints were 5-year overall survival (OS) and disease-free survival (DFS). The model performance was evaluated in terms of discrimination and calibration. Missing data were handled with multiple imputation. Of all 3581 eligible patients, 1868 were included. The 5-year OS and DFS were 85.2% and 81.9%. The IPBS model showed acceptable discrimination: C-statistics 0.706 to 0.728 for OS and 0.675 to 0.689 for DFS at 5 years. However, the IPBS model minimally overestimated both OS and DFS predictions. These overestimations were corrected after model recalibration. In this external validation study, the IPBS model exhibited good discriminative ability. Although it may provide minimal overestimation, recalibrating the model to the local context is a practical solution to improve the model calibration.

Cancer survival in Thailand from 1997 to 2012: Assessing the impact of universal health coverage.

BACKGROUND: In recent decades, many countries worldwide have implemented some form of Universal Health Coverage (UHC). We sought to evaluate incidence and survival trends of breast, cervical, and colorectal cancer before and after the implementation of UHC in Thailand. METHODS: The age-standardized incidence rate and 1- and 5-year net survival (NS) were calculated for five Thai provinces, namely Bangkok, Chiang Mai, Khon Kaen, Lampang, and Songkhla for breast, cervix, and colorectal cancer in three study periods (1997-2012): before, during, and after the implementation of UHC. RESULTS: The incidence of breast and colorectal cancer has increased over time, while the incidence of cervical cancer has decreased (17.9-29.9, 9.0-13.6, and 19.6-12.3 per 100,000, respectively). Larger proportion of breast cancer were diagnosed with localized stage after UHC implementation compared to the period prior to UHC (31.5 % vs 19.0 %). Overall, The improvement in survival by cancer site varied in magnitude with a 5-year NS increase from 61.3 % to 75.1 % for breast, 55.4-59.5 % for cervical, and 39.9-47.6 % for colorectal cancer. The amount of increase slightly differed across provinces. CONCLUSION: Rising incidence for breast and colorectal, and declining cervical cancer may partly be attributable to improved awareness and early detection programs. Additionally, improvement in survival may partly be attributable to increased access to healthcare, availability of treatment, and increased access to cancer screening after UHC was implemented. Thus, continued expansion of UHC package on cancer could potentially contribute to further improvement of cancer control in Thailand. POLICY SUMMARY: This study provides important evidence on the impact of UHC in cancer burden and survival for breast, cervical, and colorectal cancer in Thailand. This study serves as an example for other countries where UHC has been recently implemented and guide policymakers in allocating resources towards UHC and cancer control programs.

Comparison of Cholangiocarcinoma and Hepatocellular Carcinoma Incidence Trends from 1993 to 2012 in Lampang, Thailand.

Liver cancer is the most common cancer in Northern Thailand, mainly due to the dietary preference for raw fish, which can lead to infection by the parasite, O. viverrini, a causal agent of cholangiocarcinoma. We conducted a temporal trend analysis of cross-sectional incidence rates of liver cancer in Lampang, Northern Thailand. Liver cancer data from 1993-2012 were extracted from Lampang Cancer Registry. The multiple imputation by chained equations method was used to impute missing histology data. Imputed data were analyzed using Joinpoint and age-period-cohort (APC) models to characterize the incidence rates by gender, region, and histology, considering hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). We observed a significant annual increase in CCA incidence and a considerable decrease in HCC incidence for both genders in Lampang. The APC analysis suggested that CCA incidence rates were higher in older ages, younger cohorts, and later years of diagnosis. In contrast, HCC incidence rates were higher in older generations and earlier years of diagnosis. Further studies of potential risk factors of CCA are needed to better understand and address the increasing burden of CCA in Lampang. Our findings may help to draw public attention to cholangiocarcinoma prevention and control in Northern Thailand.

Descriptive epidemiology of soft tissue sarcomas and gastrointestinal stromal tumors in Thailand.

This study aimed to analyze burden of STS and GIST in population and survival rate which represented the current situation of treatment in Thailand. The data was collected from five population-based cancer registries around the country for the period 2001 through 2015. The Segi world standard population was used to calculated age-standardized incidence rates (ASR). Standardized rate ratios (SRR) were used to compare populations. Joinpoint Trend Analysis was used to assess changes in incidence. STATA was used to examine patient survival rates. During the study period, 4080 cases of STS and 457 cases of GIST were reported. The ASR of STS and GIST was 2.14/100,000 person-years and 0.22/100,000 person-years, respectively. The most common histological types of STS were unspecified sarcoma (24.8%), leiomyosarcoma (19.0%) and liposarcoma (11.4%). The overall ASR of STS in Thailand was relatively low compared to Western countries. The five-year survival rate was 62.6% for STS and 63.4% for GIST, which was comparable to the rates reported in other countries. This is the first report of STS and GIST from PBCRs in Thailand. Based on current healthcare service, an overall survival rates of STS and GIST are comparable to those reported from others.

Geographical risk pattern and temporal trends in incidence of HPV-related cancers in northern Thailand: A population-based study.

BACKGROUND: The burden of HPV-related cancers in different regions worldwide varies according to several factors. This study aims to measure inequality in the risk of incidence of HPV-related cancers in term of geographical risk patterns in northern Thailand using a population-based cancer registry data. METHODS: Trends in age-standardized HPV-related cancer incidence were calculated for the 2008-2017 time period. The Besag-York-Molli´e model was used to explore the spatial distribution of the relative risk (RR) of HPV-related cancers at the district level. A higher RR reflects a larger disparity. The geographical risk pattern of the diseases in two periods, 2008-2012 and 2013-2017 were described and compared. RESULTS: From 2008 to 2017, the incidence of oropharyngeal and anal cancers showed a slightly increased trend in males but remained stable in females, the incidence of vulvar, vaginal and penile cancers were stable while the incidence of cervical cancer decreased. The RR range was closer to 1 in the second period compared to the first period. This suggests a decrease in the disparities of incidence of cervical cancer. However, in some areas near the Thai-Myanmar border, the RR values remained high. CONCLUSION: The incidence rate of most HPV-related cancers remained low and stable over the study period in northern Thailand. For the most common HPV-related malignancy, cervical cancer, the incidence rate steadily decreased but with marked geographic disparities, possibly reflecting health inequity especially in the border areas.

Estimation of lung cancer deaths attributable to indoor radon exposure in upper northern Thailand.

Radon exposure is the second leading cause of lung cancer, after smoking. In upper northern Thailand (UNT), lung cancer incidence was frequently reported by Thailand National Cancer Institute. Besides smoking, radon exposure may also influence the high lung cancer incidence in this region. Indoor radon concentrations were measured in 192 houses in eight provinces of UNT. Indoor radon concentrations ranged from 11 to 405 Bq m-3 and estimated annual effective dose ranged from 0.44 to 12.18 mSv y-1. There were significant differences in indoor radon concentrations between the houses of lung cancer cases and healthy controls (p = 0.033). We estimated that 26% of lung cancer deaths in males and 28% in females were attributable to indoor radon exposure in this region. Other factors influencing indoor radon levels included house characteristics and ventilation. The open window-to-wall ratio was negatively associated with indoor radon levels (B = -0.69, 95% CI -1.37, -0.02) while the bedroom location in the house and building material showed no association. Indoor radon hence induced the fractal proportion of lung cancer deaths in UNT.

An analysis of the incidence and survival rates of bone sarcoma patients in thailand: reports from population-based cancer registries 2001-2015.

BACKGROUND: Epidemiology data from population-based cancer registries (PBCR) can be very valuable in the development of health policy and for improving the quality of cancer control strategies. METHODS: This study analyzed the incidence of bone sarcomas in Thailand during 2001 - 2015 by analyzing data obtained from 5 PBCRs across country. Incidence rates per million person-years by sex, histological subtype, primary site and 5-year age group were calculated. Age-standardized incidence rates (ASR) were adjusted using the WHO's World Standard Population and comparisons between populations were done using standardized rate ratios (SRR). Incidence trends were evaluated using Joinpoint Trend Analysis. Survival rates were analyzed using STATA. RESULTS: The ASR of bone sarcomas in Thailand was 5.1/106 person-years, with an estimated 328 newly diagnosed bone sarcomas per year for the country overall. Osteosarcoma (52.5%), chondrosarcoma (18%), Ewing's sarcoma (11.6%), giant cell tumor (4.8%) and chordoma (4.7%) were the most common malignant bone tumors, representing 91.5% of all bone sarcomas. Bone sarcoma has a predilection for males (1.29:1) and an age-specific bimodal rate pattern closely related to the major histological subtypes, osteosarcoma. One- and five-year survival rates of Thai patients with bone sarcoma were 74% and 52%, respectively. Survival rates of bone sarcomas, particularly osteosarcoma, were lower than the rates reported from the United States, Europe and Japan. CONCLUSION: The lower overall survival rate of bone sarcoma represented the gap of bone sarcoma control program in Thailand. That indicates the need for improvement in health promotion, treatment process and chemotherapy for bone sarcoma patients in the future.

Disparities in the change of cervical cancer mortality rate between urban and rural Chiang Mai in the era of universal health care and the Thai national screening program.

BACKGROUND: The Ministry of Public Health of Thailand established universal health coverage (UHC) in 2002, which also included national-level screening for cervical cancer in 2005. This study examined the changes in mortality of cervical cancer in rural and urban areas in Chiang Mai Province of northern Thailand during the era of UHC and the immediately preceding period. METHODS: Data of cervical cancer patients in Chiang Mai in northern Thailand, who died from 1998 through 2012, were used to calculate the change in age-standardized rates of mortality (ASMR) using a joinpoint regression model and to calculate estimated annual percent changes (APC). The change in mortality rate by age groups along with changes by geographic area of residence were determined. RESULTS: Among the 1177 patients who died from cervical cancer, 13(1%), 713 (61%) and 451 (38%) were in the young age group (aged < 30), the screening target group (aged 30-59) and the elderly group (aged ≥60), respectively. The mortality rate among women aged 30-59 significantly declined by 3% per year from 2003 through 2012 (p < 0.001). By area of residence, the mortality rate in women targeted by the screening program significantly decreased in urban areas but remained stable in more rural areas, APC of - 7.6 (95% CI: - 12.1 to - 2.8) and APC of 3.7 (95% CI: - 2.1 to 9.9), respectively. CONCLUSION: The UHC and national cervical cancer screening program in Thai women may have contributed to the reduction of the mortality rate of cervical cancer in the screening target age group. However, this reduction was primarily in urban areas of Chiang Mai, and there was no significant impact on mortality in more rural areas. These results suggest that the reasons for this disparity need to be further explored to equitably increase access to cervical cancer services of the UHC.

Individualized Prediction of Breast Cancer Survival Using Flexible Parametric Survival Modeling: Analysis of a Hospital-Based National Clinical Cancer Registry.

Prognostic models for breast cancer developed from Western countries performed less accurately in the Asian population. We aimed to develop a survival prediction model for overall survival (OS) and disease-free survival (DFS) for Thai patients with breast cancer. We conducted a prognostic model research using a multicenter hospital-based cancer clinical registry from the Network of National Cancer Institutes of Thailand. All women diagnosed with breast cancer who underwent surgery between 1 January 2010 and 31 December 2011 were included in the analysis. A flexible parametric survival model was used for developing the prognostic model for OS and DFS prediction. During the study period, 2021 patients were included. Of these, 1386 patients with 590 events were available for a complete-case analysis. The newly derived individualized prediction of breast cancer survival or the IPBS model consists of twelve routinely available predictors. The C-statistics from the OS and the DFS model were 0.72 and 0.70, respectively. The model showed good calibration for the prediction of five-year OS and DFS. The IPBS model provides good performance for the prediction of OS and PFS for breast cancer patients. A further external validation study is required before clinical implementation.

Subtype Specific Nasopharyngeal Carcinoma Incidence and Survival Trends: Differences between Endemic and Non-Endemic Populations.

BACKGROUND: While nasopharyngeal carcinoma (NPC) is rare in non-endemic regions such as the North America, endemic countries, such as Thailand, continue to struggle with high incidence and mortality rates. NPC has a complex etiology that varies by histological subtype. METHODS: NPC cases (1990-2014) were identified using the International Classification of Diseases for Oncology (ICD-O) code C11 from the Chiang Mai, Khon Kaen, Lampang, and Songkhla cancer registries and compared to Asian/Pacific Islanders (A/PI) from the US SEER program. Age-standardized incidence rates and changes in annual percent change (APC) for overall and subtype specific NPC were assessed using R and Joinpoint. Kaplan Meier curves were generated in SAS to evaluate differences in survival by sex, year of diagnosis and histological subtype. Five-year relative survival estimates were calculated between 2000-2014. RESULTS: Non-keratinizing NPC predominated across all registries except Songkhla, where the keretinizing subtype made up ~60% of all reported cases. Incidence of keratinizing NPC significantly decreased among Chiang Mai males between 1996 and 2014 (APC:-13.0 [95%CI:-16.2, -9.6]), Songkhla females (APC:-4.0 [95%CI: -7.4, -0.5]) and males between 2006 and 2014 (APC:-15.5 [95%CI:-25.0, -4.7]), as well as A/PI females (APC:-5.1 [95%CI:-6,7, -3.4]) and males (APC: -4.8 [95%CI:-5.9, -3.7]). Non-keratinizing NPC increased among Songkhla males (APC:4.3 [95%CI:1.8, 6.9]). The keratinizing subtype exhibited the worst survival, while the non-keratinizing undifferentiated subtype had the best survival. Although US A/PI had the highest 5-year relative survival estimates, among the Thai registries Chiang Mai had the best and Lampang the worst survival. CONCLUSION: Although US A/PIs exhibited similar rates of NPC as seen in the endemic Thai population, improved tobacco control has led to a decrease in keratinizing NPC incidence irrespective of geography. Additionally, while challenges associate with access to care may still exist among rural Thais, chemoradiation was shown to confer a survival benefit in non-keratinizing NPC treatment.

Classification of hepatocellular carcinoma and intrahepatic cholangiocarcinoma based on multi-phase CT scans.

Liver and bile duct cancers are leading causes of worldwide cancer death. The most common ones are hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). Influencing factors and prognosis of HCC and ICC are different. Precise classification of these two liver cancers is essential for treatment and prevention plans. The aim of this study is to develop a machine-based method that differentiates between the two types of liver cancers from multi-phase abdominal computerized tomography (CT) scans. The proposed method consists of two major steps. In the first step, the liver is segmented from the original images using a convolutional neural network model, together with task-specific pre-processing and post-processing techniques. In the second step, by looking at the intensity histograms of the segmented images, we extract features from regions that are discriminating between HCC and ICC, and use them as an input for classification using support vector machine model. By testing on a dataset of labeled multi-phase CT scans provided by Maharaj Nakorn Chiang Mai Hospital, Thailand, we have obtained 88% in classification accuracy. Our proposed method has a great potential in helping radiologists diagnosing liver cancer.

Impact of universal health care and screening on incidence and survival of Thai women with cervical cancer: A population-based study of the Chiang Mai Province.

Universal Health Coverage (UHC) was implemented in Thailand in 2002. This study aims to compare cervical cancer incidence and survival before and after the implementation of UHC, including the national screening program, in the Chiang Mai population in Northern Thailand. Data of women diagnosed with in situ or malignant cervical cancer in Chiang Mai during 1998-2012 were used in our analysis. Annual age-standardized incidence rates (ASR) and age-adjusted relative survival (RS) were estimated for the following three diagnosis periods: period I: 1998-2002 (before UHC), period II: 2003-2007 (UHC implementation) and period III: 2008-2012 (after UHC). The ASR peaked in 2001 at 38 per 100,000, and then subsequently declined to 23 per 100,000 in 2012. The proportion of in situ and localized tumors increased in all age groups, while regional tumors declined. In all women (aged 15-89) with malignant cervical cancer or in situ, the 5-year RS in Period I, Period II and Period III was 73%, 74% and 77%, respectively; when only malignant cases were considered, the RS was 63%, 61% and 62%, respectively. In the screening target women (aged 30-59) with malignant or in situ tumors, the 5-year RS was 84%, 88% and 90%, respectively, in the three periods, while the RS was 71%, 74% and 75%, respectively, in only those with malignant cancers. The introduction of UHC including national cervical cancer screening program has likely reduced the magnitude and severity of cervical cancer and improved the survival of cervical cancer in the screening target age group.

Temporal Changes in Head and Neck Cancer Incidence in Thailand Suggest Changing Oropharyngeal Epidemiology in the Region.

PURPOSE: Head and neck cancer is the sixth most common cancer in the world, and the largest burden occurs in developing countries. Although the primary risk factors have been well characterized, little is known about temporal trends in head and neck cancer across Thailand. METHODS: Head and neck squamous cell carcinoma (HNSCC) occurrences diagnosed between 1990 and 2014 were selected by International Classification of Diseases (10th revision; ICD10) code from the Songkhla, Lampang, Chiang Mai, and Khon Kaen cancer registries and the US SEER program for oral cavity (ICD10 codes 00, 03-06), tongue (ICD10 codes 01-02), pharynx (ICD10 codes 09-10, 12-14), and larynx (ICD10 code 32). The data were analyzed using R and Joinpoint regression software to determine age-standardized incidence rates and trends of annual percent change (APC). Incidence rates were standardized using the Segi (1960) population. Stratified linear regression models were conducted to assess temporal trends in early-onset HNSCC across 20-year age groups. RESULTS: Although overall HNSCC rates are decreasing across all registries, subsite analyses demonstrate consistent decreases in both larynx and oral cavity cancers but suggest increases in tongue cancers among both sexes in the United States (APCmen, 2.36; APCwomen, 0.77) and in pharyngeal cancer in Khon Kaen and US men (APC, 2.1 and 2.23, respectively). Age-stratified APC analyses to assess young-onset (< 60 years old) trends demonstrated increased incidence in tongue cancer in Thailand and the United States as well as in pharyngeal cancers in Khon Kaen men age 40 to 59 years and US men age 50 to 59 years. CONCLUSION: Although overall trends in HNSCC are decreasing across both Thailand and the United States, there is reason to believe that the etiologic shift to oropharyngeal cancers in the United States may be occurring in Thailand.

Childhood cancer incidence and survival in Thailand: A comprehensive population-based registry analysis, 1990-2011.

BACKGROUND: Southeast Asia is undergoing a transition from infectious to chronic diseases, including a dramatic increase in adult cancers. Childhood cancer research in Thailand has focused predominantly on leukemias and lymphomas or only examined children for a short period of time. This comprehensive multisite study examined childhood cancer incidence and survival rates in Thailand across all International Classification of Childhood Cancer (ICCC) groups over a 20-year period. METHODS: Cancer cases diagnosed in children ages 0-19 years (n = 3574) from 1990 to 2011 were extracted from five provincial population-based Thai registries, covering approximately 10% of the population. Descriptive statistics of the quality of the registries were evaluated. Age-standardized incidence rates (ASRs) were calculated using the Segi world standard population, and relative survival was computed using the Kaplan-Meier method. Changes in incidence and survival were analyzed using Joinpoint Regression and reported as annual percent changes (APC). RESULTS: The ASR of all childhood cancers during the study period was 98.5 per million person-years with 91.0 per million person-years in 1990-2000 and 106.2 per million person-years in 2001-2011. Incidence of all childhood cancers increased significantly (APC = 1.2%, P < 0.01). The top three cancer groups were leukemias, brain tumors, and lymphomas. The 5-year survival for all childhood cancers significantly improved from 39.4% in 1990-2000 to 47.2% in 2001-2011 (P < 0.01). CONCLUSIONS: Both childhood cancer incidence and survival rates have increased, suggesting improvement in the health care system as more cases are identified and treated. Analyzing childhood cancer trends in low- and middle-income countries can improve understanding of cancer etiology and pediatric health care disparities.

Risk patterns of lung cancer mortality in northern Thailand.

BACKGROUND: Over the past decade, lung cancers have exhibited a disproportionately high mortality and increasing mortality trend in Thailand, especially in the northern region, and prevention strategies have consequently become more important in this region. Spatial analysis studies may be helpful in guiding any strategy put in place to respond to the risk of lung cancer mortality in specific areas. The aim of our study was to identify risk patterns for lung cancer mortality within the northern region of Thailand. METHODS: In the spatial analysis, the relative risk (RR) was used as a measure of the risk of lung cancer mortality in 81 districts of northern Thailand between 2008 and 2017. The RR was estimated according to the Besag-York-Mollié autoregressive spatial model performed using the OpenBUGS routine in the R statistical software package. We presented the overall and gender specific lung cancer mortality risk patterns of the region using the Quantum Geographic Information System. RESULTS: The overall risk of lung cancer mortality was the highest in the west of northern Thailand, especially in the Hang Dong, Doi Lo, and San Pa Tong districts. For both genders, the risk patterns of lung cancer mortality indicated a high risk in the west of northern Thailand, with females being at a higher risk than males. CONCLUSIONS: There was distinct geographical variation in risk patterns of lung cancer mortality in Thailand. Differences could be related to differences in risk factors such as ground-based radon and air pollution. This study provides a starting point for estimating the spatial pattern of the risk of lung cancer mortality and for examining associations between geographic risk factors and lung mortality for further studies.

Temporal Trends and Geographic Patterns of Lung Cancer Incidence by Histology in Thailand, 1990 to 2014.

Purpose Lung cancer is one of the most common cancers worldwide and in Thailand. We characterize and forecast region-specific patterns of lung cancer incidence by histology and sex. Methods We analyzed lung cancer incidence trends in Thailand by histology (adenocarcinoma [AdC]; squamous cell carcinoma [SCC]; and large-cell, small-cell, and other carcinomas) from 1990 to 2014 in four cancer registries in three regions (north, Chiang Mai Province and Lampang Province; northeast: Khon Kaen Province; south: Songkhla Province). Annual percent change (APC) was calculated to quantify the incidence rate trends using joinpoint regression. Age-period-cohort models were used to examine the temporal trends of AdC and SCC by age, calendar year, and birth cohort. We projected the incidence of AdC and SCC up to 2030 using three independent approaches: joinpoint, age-period-cohort, and Nordpred models. Results AdC incidence significantly increased from 1990 to 2012 in Chiang Mai males (APC, 1.3%), Songkhla males from 2004 to 2014 (APC, 2.5%), Songkhla females from 1990 to 2014 (APC, 5.9%), and Khon Kaen females from 2005 to 2014 (APC, 3.1%). Conversely, SCC incidence significantly decreased from 1990 to 2012 in Chiang Mai males and females (APC, -1.2% and -4.8%, respectively), Lampang males and females from 1993 to 2014 (APC, -5.4% and -5.2%, respectively), and Songkhla females from 1990 to 2014 (APC, -2.1%). In general, trends of AdC and SCC correlated more with birth cohort than with calendar year. Three projection models suggested that incidence rates of AdC in Songkhla may continue to increase until 2030. Conclusion Temporal trends of lung cancer by histology varied among regions in Thailand. Reduction of lung cancer incidence in Thailand likely will require prevention strategies tailored to each specific region.

Cancer incidence in northern Thailand: Results from six population-based cancer registries 1993-2012.

Rapid changes in social and economic development have led to cancer becoming a major cause of national morbidity and mortality in Thailand. Cancer registries have been critical in documenting subnational cancer patterns and transitions in the country; with the establishment of six registries in northern Thailand, a comprehensive assessment of the scale and profile of cancer is now possible in the region. Cancers of the liver, lung, colorectum, breast and cervix were the major cancers 2008-2012, although variations in the profiles of cancer were observed, with a very high incidence of liver cancer seen among males in Phrae, corresponding to one in 11 men developing the disease in a lifetime. Based on data from Lampang and Chiang Mai 1993-2012, rates of lung and cervical cancer incidence have declined, while liver, colorectal and breast cancer incidence have been increasing up to 2012. A more detailed investigation of the incidence trends for specific cancer sites and subtypes at the local level are crucial to the monitoring and evaluation of the cancer control interventions implemented within the Thai national cancer control programme (NCCP). Priority should be given to extend the capacity of the new registries in northern Thailand, ensuring improvement in quality and utilization of the data to drive epidemiologic research and cancer control.

National and Subnational Population-Based Incidence of Cancer in Thailand: Assessing Cancers with the Highest Burdens.

In Thailand, five cancer types-breast, cervical, colorectal, liver and lung cancer-contribute to over half of the cancer burden. The magnitude of these cancers must be quantified over time to assess previous health policies and highlight future trajectories for targeted prevention efforts. We provide a comprehensive assessment of these five cancers nationally and subnationally, with trend analysis, projections, and number of cases expected for the year 2025 using cancer registry data. We found that breast (average annual percent change (AAPC): 3.1%) and colorectal cancer (female AAPC: 3.3%, male AAPC: 4.1%) are increasing while cervical cancer (AAPC: -4.4%) is decreasing nationwide. However, liver and lung cancers exhibit disproportionately higher burdens in the northeast and north regions, respectively. Lung cancer increased significantly in northeastern and southern women, despite low smoking rates. Liver cancers are expected to increase in the northern males and females. Liver cancer increased in the south, despite the absence of the liver fluke, a known factor, in this region. Our findings are presented in the context of health policy, population dynamics and serve to provide evidence for future prevention strategies. Our subnational estimates provide a basis for understanding variations in region-specific risk factor profiles that contribute to incidence trends over time.

Trends in Female Breast Cancer by Age Group in the Chiang Mai Population

Objectives: This study was conducted to determine incidence trends of female breast cancer according to age groups and to predict future change in Chiang Mai women through 2028. Method: Data were collected from all hospitals in Chiang Mai in northern Thailand, from 1989 through 2013, and used to investigate effects of age, year of diagnosis (period) and year of birth (cohort) on female breast cancer incidences using an age-period-cohort model. This model features geometric cut trends to predict change by young (<40 years), middle-aged (40-59) and elderly (≥60) age groups. Result: Of 5, 417 female breast cancer patients with a median age of 50 years (interquartile range: 43 to 59 years), 15%, 61% and 24% were young, middle-aged and elderly, respectively. Seventy nine percent of cancer cases in this study were detected at advanced stage. The trend in stage classification showed an increase in percentage of early stage and a decrease in metastatic cancers. Linear trends for cohort and period were not found in young females but were observed in middle-aged and elderly groups. Age-standardized rates (ASR) can be expected to remain stable around 6.8 per 100,000 women-years in young females. In the other age groups, the ASR trends were calculated to increase and reach peaks in 2024 of 120.2 and 138.2 per 100,000 women-years, respectively. Conclusion: Cohort effects or generation-specific effects, such as life style factors and the year of diagnosis (period) might have impacted on increased incidence in women aged over 40 years but not those under 40 years. A budget should be provided for treatment facilities and strategies to detect early stage cancers. The cost effectiveness of screening measures i.e. mammographic screening may need to be reconsidered for women age over 40 years.