Cervical cancer screening in Thailand: an overview.

In Thailand, there have been no 'organized' programmes of screening for cervical cancer. For the most part, screening has been unsystematic or provided to women 'on demand'. In 2002, the Department of Medical Services of the Ministry of Public Health proposed the screening of the entire population of women in Thailand at 5-yearly intervals from the ages of 35 to 60 years. As a first step, measures to increase the capacity for obtaining and interpreting papanicolaou (Pap) smears have been put in place. Research studies have examined the effectiveness of screening with Pap smears in Thailand, and confirmed that, as elsewhere, protection is related to the number of previous tests and the time elapsed since the most recent one. Coverage of the population remains low. Other methods of screening are being investigated in Thailand, including visual inspection following acetic acid (VIA), followed by immediate treatment of observed lesions by cryotherapy ('see and treat'). Other research studies have examined the acceptability and performance of self-sampling as a means of obtaining Pap smears, and the use of mobile clinics to increase coverage of at-risk women in rural settings. Human papillomavirus (HPV) testing has been used to identify high-risk women, or to help decide which women with low-grade abnormality on cytology should undergo more intensive follow-up. Prevalence of HPV in normal women in Thailand is 9-20%, but HPV testing has not been used on any systematic basis to date. Current screening programmes in Thailand are not very effective. The national cancer control programme aims to increase the coverage of screening. The population-based cancer registry will provide an effective and economical method of evaluating the impact of early diagnosis and screening at community level.