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.     

Spatial and Temporal Analyses of Cervical Cancer Patients in Upper Northern Thailand

Background: Cervical cancer is a major public health problem worldwide. There have been several studies indicating that risk is associated with geographic location and that the incidence of cervical cancer has changed over time. In Thailand, incidence rates have also been found to be different in each region. Methods: Participants were women living or having lived in upper Northern Thailand and subjected to cervical screening at Maharaj Nakorn Chiang Mai Hospital between January 2010 and December 2014. Generalized additive models with Loess smooth curve fitting were applied to estimate the risk of cervical cancer. For the spatial analysis, Google Maps were employed to find the geographical locations of the participants’ addresses. The Quantum Geographic Information System was used to make a map of cervical cancer risk. Two univariate smooths: x equal to the residency duration was used in the temporal analysis of residency duration, and x equal to the calendar year that participants moved to upper Northern Thailand or birth year for participants already living there, were used in the temporal analysis of the earliest year. The spatial-temporal analysis was conducted in the same way as the spatial analysis except that the data were split into overlapping calendar years. Results: In the spatial analysis, the risk of cervical cancer was shown to be highest in the Eastern sector of upper Northern Thailand (p-value <0.001). In the temporal analysis of residency duration, the risk was shown to be steadily increasing (p-value =0.008), and in the temporal analysis of the earliest year, the risk was observed to be steadily decreasing (p-value=0.016). In the spatial-temporal analysis, the risk was stably higher in Chiang Rai and Nan provinces compared to Chiang Mai province. According to the display movement over time, the odds of developing cervical cancer declined in all provinces. Conclusions: The risk of cervical cancer has decreased over time but, in some areas, there is a higher risk than in the major province of Chiang Mai. Therefore, we should promote cervical cancer screening coverage in all areas, especially where access is difficult and/or to women of lower socioeconomic status.     

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.     

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.     

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 (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.     

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.     

Prevalence and Survival Patterns of Patients with Bone Metastasis from Common Cancers in Thailand

Background: Bone metastasis is a single condition but presents with various patterns and severities. Skeletal- related events (SREs) deteriorate overall performance status and reduce quality of life. However, guidelines for early detection and management are limited. This study includes a survey of the prevalence of bone metastasis in cases with common cancers in Thailand as well as a focus on survival patterns and SREs. Materials and Methods: A retrospective cohort analysis was conducted using a database of the Chiang Mai Cancer Registry and the Musculoskeletal Tumor Registry of the OLARN Center, Chiang Mai University. The prevalence of bone metastasis from each type of primary cancer was noted and time-to-event analysis was performed to estimate cancer survival rates after bone metastasis. Results: There were 29,447 cases of the ten most common cancers in Thailand, accounting for 82.2% of the entire cancer registry entries during the study period. Among those cases, there were 2,263 with bone metastases, accounting for 7.68% of entries. Bone metastasis from lung, liver, breast, cervix and prostate are common in the Thai population, accounting for 83.4% of all positive cases. The median survival time of all was 6 months. Of the bone metastases, 48.9% required therapeutic intervention, including treatment of spinal cord and nerve root compression, pathological fractures, and bone pain. Conclusions: The frequency of the top five types of bone metastasis in Thailand were different from the frequencies in other countries, but corresponded to the relative prevalence of the cancers in Thailand and osteophilic properties of each cancer. The results of this study support the establishment of country specific guidelines for primary cancer identification with skeletal lesions of unknown origin. In addition, further clinical studies of the top five bone metastases should be performed to develop guidelines for optimal patient management during palliative care.     

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.     

Epidemiology of head and neck cancer in Thailand

Cancer is the most common cause of death in Thailand, with the mortality almost doubled during 1998–2011 (from 48.4 to 95.2 per 100 000). The estimated number of new cancer cases in 2011 was 112 392. Our review provides baseline data on the current epidemiological situation with head and neck (HN) cancer in Thailand based on reports of the National Cancer Registry and findings from local and international publications. Collectively, HN cancer approaches age‐standardized rate (ASR) incidence of 15.7 and 10.7 per 100 000 males and females, respectively, and is ranked among the top five dominant cancers in Thailand. The leading HN malignancies in men are oral (ASR incidence 4.6 per 100 000), nasopharyngeal (ASR 2.8) and laryngeal (ASR 2.7) cancers, while the most common cancers in women are thyroid (ASR 5.1) and oral (ASR 3.2) carcinomas. Some local habits (betel quid chewing, traditional cigarette smoking and alcohol intake) are associated with the high incidence of oral cancer in Northeast Thailand. Despite important prognostic significance, the role of human papillomavirus infection in various HN cancers from Thailand has been scarcely addressed. There is a growing incidence of thyroid cancer over the last two decades. The Thai population overall, compared to worldwide rates of HN malignancies, has a lower incidence of laryngeal and thyroid cancers but higher incidence of nasopharyngeal cancer.     

Differences in Cancer Risks in the South and North of Viet Nam

Background: As there are few available data regarding cancers in Viet Nam, the aim of the present study was toevaluate cancer risk ratios and geographical differences in cancer incidences between the south and north populationsin the 1990s.Methods: Data for cancer incidences in Ho Chi Minh (HCM) and Hanoi were derived from published reports.The method for comparison of cancer incidence in two groups used in the present study was the Mantel-Haenszeltest.Results: In HCM, all cancers were observed to be lower in males , (RR = 0.87, 95% CI = 0.83-0.91) but higher infemales, (RR = 1.06, 95% CI = 1.01-1.12) than in Hanoi. For males, significantly higher incidences in HCM wereobserved for cancers of the oesophagus (RR = 1.66, 95% CI = 1.19-2.32), liver (RR = 1.22, 95% CI = 1.09-1.36), gallbladder (RR = 5.95, 95% CI = 2.49-14.23), and larynx (RR = 3.54, 95% CI = 2.26-5.55). In contrast, there were muchlower incidences in HCM for cancers of the nasopharynx (RR = 0.5, 95% CI = 0.41-0.61), stomach (RR = 0.76, 95%CI = 0.67-0.86), and lung (RR = 0.7, 95% CI = 0.64-0.78). For females, breast cancer incidence was much lower (RR= 0.65, 95% CI = 0.57-0.73) but that of cervical cancer was significantly higher in HCM than in Hanoi, (RR = 3.94,95% CI = 3.36-4.62), especially for the age group 55-64, (RR = 8.7, 95% CI = 5.9-13.3).Conclusion: The present findings show that cancer risk is quite different in the south and north populationswithin Viet Nam.     

Cancer in Chiang Mai, North Thailand. A relative frequency study

The relative frequency of histologically diagnosed cancer at the Chiang Mai Medical School in North Thailand in 1964-67 inclusive is examined.     

Breast Cancer in Surat Thani,a Province in Southern Thailand: Analysis of 2004-2012 Incidence and Future Trends

Background: With the recent epidemiologic transition in Thailand, featuring decreasing incidences ofinfectious diseases along with increasing rates of chronic conditions, cancer is becoming a serious problem forthe country. Breast cancer has the highest incidence rates among females, not only in the southern regions, butthroughout Thailand. Surat Thani is a province in the upper part of Southern Thailand. A study was neededto identify the current burden, and the future trends of breast cancer. Materials and Methods: Here we usedcancer incidence data from the Surat Thani Cancer Registry to characterize the incidences of breast cancer.Joinpoint analysis was used to investigate the incidences in the province from 2004 to 2012 and to project futuretrends from 2013 to 2030. Results: Age-standardized incidence rates (world) of breast cancer in the upper partsof Southern Thailand increased from 35.1 to 59.2 cases per 100,000 female population, which is equivalent toan annual percentage change of 4.5-4.8%. Linear drift effects played a role in shaping the increase of incidence.Joinpoint projection suggested that incidence rates would continue to increase in the future with incidence forwomen aged 50 and above, at a higher rate than for women below the age of 50. Conclusions: The current earlydetection measures increase detection rates of early disease. Preparation of a budget for treatment facilities andhuman resources, both in surgical and medical oncology, is essential.     

Geographical and spatial disparities in the incidence and survival of rare cancers in Australia

Rare cancers collectively account for around a quarter of cancer diagnoses and deaths. However, epidemiological studies are sparse. We describe spatial and geographical patterns in incidence and survival of rare cancers across Australia using a population-based cancer registry cohort of rare cancer cases diagnosed among Australians aged at least 15 years, 2007 to 2016. Rare cancers were defined using site- and histology-based categories from the European RARECARE study, as individual cancer types having crude annual incidence rates of less than 6/100 000. Incidence and survival patterns were modelled with generalised linear and Bayesian spatial Leroux models. Spatial heterogeneity was tested using the maximised excess events test. Rare cancers (n = 268 070) collectively comprised 22% of all invasive cancer diagnoses and accounted for 27% of all cancer-related deaths in Australia, 2007 to 2016 with an overall 5-year relative survival of around 53%. Males and those living in more remote or more disadvantaged areas had higher incidence but lower survival. There was substantial evidence for spatial variation in both incidence and survival for rare cancers between small geographical areas across Australia, with similar patterns so that those areas with higher incidence tended to have lower survival. Rare cancers are a substantial health burden in Australia. Our study has highlighted the need to better understand the higher burden of these cancers in rural and disadvantaged regions where the logistical challenges in their diagnosis, treatment and support are magnified.     

AgeStandardized Incidence Rates and Survival of Osteosarcoma in Northern Thailand

Osteosarcoma is a common primary malignant bone tumor in children and adolescents. Recent worldwide average incidences of osteosarcoma in people aged 0 to 24 years were 4.3 and 3.4 per million, respectively, with a ratio of 1.4:1. However, data on the incidence of osteosarcoma in Thailand are limited. This study analyzed the incidence of osteosarcoma in the upper northern region of Thailand, with a population of 5.85 million people (8.9% of the total Thai population), using data for the years 1998 to 2012, obtained from the Chiang Mai Cancer Registry (CMCR) at Chiang Mai University Hospital and the Lampang Cancer Registry (LCR) at the Lampang Cancer Hospital, a total of 144 cases. The overall annual incidence of osteosarcoma was 1.67 per million with a male:female ratio of 1.36:1. Incidences by age group (male and female) at 0 to 24, 25 to 59 and over 60 years were 3.5 (3.9 and 3.0), 0.8 (0.9 and 0.6), and 0.7 (0.8 and 0.5), respectively. The peak incidence occurred at 15 to 19 years for males and at 10 to 14 years for females. The median survival time was 18 months with a 5year survival rate of 43%. Neither the age group nor the 5year interval period of treatment was significantly correlated with survival during the 15year period studied.     

中山市1970~2007年恶性肿瘤发病分析

[目的]分析中山市1970～2007年恶性肿瘤发病规律和特点,为中山市肿瘤防治提供科学依据。[方法]收集和整理中山市1970～2007年恶性肿瘤发病资料,分析其发病数、发病粗率、中国人口和世界人口标化率、发病构成和顺位等指标。[结果]1970～2007年中山市恶性肿瘤世界人口标化发病率为133.07/10万,2005～2007年为212.22/10万。1970～2007年中山市恶性肿瘤发病总体持续上升,而男性肺癌、食管癌、直肠癌、结肠癌与女性肺癌、乳腺癌、结肠癌和直肠癌发病也明显上升。[结论]虽然1970～2007年中山市恶性肿瘤发病率位于世界中等水平,女性发病率与全国水平相当,但男性发病率位于全国较高水平,且期间中山市恶性肿瘤发病率持续上升,提示中山市应加强恶性肿瘤的防治。     

Clinical Relevance of Atypical Squamous Cells of Undetermined Significance by the 2001 Bethesda System: Experience from a Cervical Cancer High Incidence Region

The aim of this study was to evaluate the underlying lesions and factors predicting cervical intraepithelialneoplasia (CIN) 2+ in women who had “atypical squamous cells of undetermined significance” (ASC-US) oncervical cytology in the region with a high incidence of cervical cancer. This study was prospectively conductedat Chiang Mai University Hospital, Chiang Mai, Thailand. All women with ASC-US cytology undergoingcolposcopic evaluation between October 2004 and August 2008 were recruited. During the study period, 208women were enrolled. Mean age was 44.4 years. The histopathologic results at the initial evaluation were asfollows: CIN 2-3, 21 (10.1%); adenocarcinoma in situ, 3 (1.4%); cancer, 5 (2.4%); CIN 1, 26 (12.5%); and nolesions, 153 (73.6%). Multivariate analysis revealed that nulliparity (adjusted odds ratio [aOR] =4.09; 95%confidence interval [CI] = 1.04-16.10) and current oral contraceptive use (aOR=2.85; 95%CI= 1.14-7.15) wereindependent predictors for having CIN 2+ at the initial colposcopy. At the median follow-up time of 6.7 months,CIN 2-3 lesions were additionally detected in 2 women. In conclusion, ASC-US cytology in our population has arelatively high prevalence of underlying invasive carcinoma. Nulliparity and current oral contraceptive use areindependent predictors for harboring CIN 2+.     

Risk Factors for Lung Cancer among Northern Thai Women: Epidemiological, Nutritional, Serological, and Bacteriological Surveys of Residents in High- and Low-incidence Areas

Lung cancer incidence among Northern Thai women is one of the highest in Asia (an annual age-adjusted incidence rate of 37.4 per 100,000), and the incidence rate significantly differs by geographical districts. Therefore, we conducted a comparative study of women living in the Sarapee area, which showed the highest (crude incidence rate, 40.9), and the Chom Tong area, which had one of the lowest incidence rates (8.5) in Chiang Mai Province, despite the two areas' geographical and cultural closeness. The women in this study were either family members of lung cancer patients or their neighbors. To find clues to the etiology of lung cancer, this study used various epidemiological and biochemical approaches: interviewing on lifestyle factors, duplicate meals, chemical examination of drinking water, biochemical analysis of sera, mutagenicity test of urine, and monitoring of fungi and bacteria in the living environment. We found that tobacco smoking (Khiyo, local cigars) was less frequently observed in Sarapee (high incidence), compared with Chom Tong (low incidence), and that the history of chronic benign respiratory diseases was the most distinct event among women in Sarapee, resulting in a significantly increased percentage of those with a history of both benign respiratory diseases and tobacco smoking. This population revealed increased levels of serum tumor necrosis factor (TNF)-α, an endogenous tumor promoter. Furthermore, significantly increased urine mutagenicity was found to be closely associated with history of benign respiratory disease in Sarapee. The fungus which was most commonly found in the air inside houses in Sarapee was identified as Microsporum canis. Additionally, significantly increased serum concentrations of a constituent of the fungus were found in Sarapee women, compared with those in Chom Tong. Our results suggest that tobacco (Khiyo) smoking alone may not be able to explain the very high incidence of female lung cancer in Northern Thailand, and that chronic benign respiratory disease, possibly caused by the infection of fungi such as M. canis, is likely to be involved in the etiology of female lung cancer in North Thailand.     

Decline of oropharyngeal cancer in Chiangmai province,Thailand, between 1988 and 1999

A decline of oropharyngeal cancer has already been predicted for Thailand since the early 1960s. To substantiate these predictions it was the purpose of this study to examine trends in the incidence of oropharyngeal cancer in the province of Chiangmai, (1988-1999). Data on cancer incidence were extracted from the annual reports of the Cancer Registry, Cancer Unit, Faculty of Medicine, Chiangmai University, Thailand (1992-1999) and an IARC report on cancer in Thailand (1988-1991). The age-standardized annual incidence per 100000 of oral cancer in males dropped from 3.6 (1988-1991) to 1.2 in 1999 (P for trend 0.0002) and in females from 2.6 (1988-1991) to 1.1 in 1999 (P for trend 0.007). Similar trends in males and females for cancer of the tongue, oropharynx and hypopharynx were seen. The age-standardized annual incidence for cancer of the lip, salivary gland and nasopharyngeal carcinoma remained unchanged. Changes of traditional oral habits such as betel quid chewing and smoking of traditional cigars seem to have resulted in a marked decrease of oral cancer in both men and women in the recent past.     

Cancer registration and healthcare access in West Bank, Palestine: a GIS analysis of childhood cancer, 1998-2007

In low and middle income countries (LMIC), high-quality disease registration is difficult to achieve in the setting of inadequate healthcare infrastructure and political or economical instability. In this article, we explore the potential of geographic information systems (GIS) to add value to the understanding of childhood cancer patterns in the West Bank, despite a variety of obstacles to disease registration. All incidence cases of childhood cancers (under the age 15) from 1998 to 2007 were collected from the West Bank Cancer Registry. Temporal, spatial and space-time analyses were performed using the SatScan software developed by Martin Kulldorff and the National Cancer Institute (NCI). The analyses were categorized into the following groups: all childhood cancer, leukemias, acute lymphocytic leukemia, lymphomas, brain and central nervous system (CNS) cancers and remaining cancers (excluding leukemia, lymphoma and CNS tumors). The temporal analysis revealed that cancer registration was more complete from 1998 to 2000 (p=0.0162), and that leukemia registration was severely deficient from 2003 to 2005 (p=0.0012). The spatial analysis showed a concentration of cancer in metropolitan districts where referral hospitals are based. Under registration was detected in the northern districts of Jenin and Tulkarm (RR=0.59, p=0.0059), more prominent from 2002 to 2005 (RR=0.33, p=0.0006). The analysis for high rates found a cluster of lymphoma in town of Dura and its surrounding agricultural villages (RR=4.10, p=0.0023). Our study reveals that the application of GIS tools to registry data in LMIC can help to identify geographical patterns in cancer registration and healthcare accessibility, generating priorities for future health research and policy in resource-limited areas.     

Cancer of the oral cavity, pharynx/larynx and lung in North Thailand: case-control study and analysis of cigar smoke.

The unusually high relative frequency of cancer in the laryngeal region in males (18% of all histologically diagnosed cancers) and a sex ratio of unity for lung cancer in Northern Thailand were further explored in a hospital-based case-control study in Chiang Mai. This compared patients having cancers of the oral cavity (including oropharynx), larynx, hypopharynx and lung, with controls in relation to smoking and chewing habits. Statistical analysis indicated that chewing betel is strongly associated with the occurrence of oral cancer in both sexes, and with cancer of the laryngeal region in males. No factors were strongly linked to lung cancer in men, but, in women, urban residence and miang chewing were associated with lung cancer. Analysis of smoke from the two main types of cigars smoked in the region showed that both had high tar content, but there were marked differences in pH. Smoking cigars with alkaline smoke and high tar had an increased risk for laryngeal cancer in males, whereas other cigars with acid smoke and high tar together with manufactured cigarettes had increased risks for lung cancer. These increased risks were not, however, statistically significant.