Monitoring and evaluation of a model demonstration project for the control of cervical cancer in Nakhon Phanom province, Thailand.

Cancer of the uterine cervix is the second most common cancer in females in the world with about half a million new patients per year. Since the introduction by Papanicolaou of cervical smear screening, the incidence of cervical cancer has declined in many developed countries. The decrease in the incidence of and mortality from cervical cancer is mainly due to the organized mass screening using Pap smear programmes. Uterine cervical cancer is the leading cancer among women in Thailand with age-standardized incidence rates of 24.7 per 100,000 in 1999. Most cases present at advanced stages with poor prognoses of survival and cure. In the present study, cervical cancer screening programme with cervical cytology was organized for Nakhon Phanom province, Thailand. The specific objectives were: 1) to evaluate the reduction in incidence and mortality from cervical cancer in the province by means of an organised low-intensity cervical cytology programme. 2) to demonstrate the different aspects of programme implementation as a potential model for nationwide implementation. The screening activities were integrated in the existing health care system. Organized screening for women in the target population (aged 35-54 years) at 5-year intervals was free of charge. Sample taking was done by trained nurses (midwives) and primary health care personnel in the local health care centers. Sample quality was under continuous controlled by the cytology laboratories and pathologists. Confirmation and treatment were integrated into the normal health care routines. The screening results of the programme, including histologically confirmed diagnosis, were registered at the National Cancer Institute using PapReg and CanReg 4 programmes. A population-based cancer registry in Nakhon Phanom province was also set up in 1997. In the period 1999-2002, 32,632 women aged 35-54 years were screened. Women with low-grade lesions returned for routine follow-up smears. High-grade preinvasive disease was further evaluated by repeating Pap smear, conization or biopsy and subsequent treatment through surgical removal or ablation. This organized low-intensity cervical cytology programme showed a considerable increase in early carcinoma in situ and CIN II -III cases and should reduce incidence of and mortality from cervical cancer in Nakhon Phanom province in the future. Screening with the Papanicolaou smear plus adequate follow-up diagnosis and therapy can achieve major reductions in both incidence and mortality rates.

Epidemiology of liver cancer: an overview.

The incidence of liver cancer varies widely throughout the world, with high rates in sub - Saharan Africa, eastern and southeastern Asia, and Melanesia and a low incidence in Northern and Western Europe and the Americas. Primary cancers of the liver in adults are of two main histological types: hepatocellular carcinoma, which is derived from hepatocytes, and cholangiocarcinoma, which is derived from the epithelial lining of the intrahepatic bile ducts. Hepatocellular cancer is a frequently occurring tumor in individuals in many developing countries, where several important risk factors have been demonstrated, including chronic infection with hepatitis B and C viruses and other environmental factors, such as exposure to aflatoxin, consumption of alcohol, and cigarette smoking. By contrast, cholangiocarcinoma is less common, accounting for only 7.7% of malignant tumors of the liver in the United States. However, in parts of Southeast Asia, cholangiocarcinoma occurs more frequently; it is responsible for more than 60% of liver tumors in northeastern Thailand. The geographic distribution worldwide coincides with endemic areas of the liver flukes, Opisthorchis viverrini and Clonorchis sinensis. The interaction between genes and the environment and the interplay of environmental factors, which include diet and other lifestyle parameters, illustrate the complexity underlying susceptibility.