Visual inspection in oral cancer screening in Cuba: a case-control study.

A case-control study was conducted to evaluate the efficacy of an on-going oral cancer screening programme in Cuba in preventing advanced oral cancer in Cuba. The cases for the study consisted of 200 oral cancer patients with stage III and IV disease. Three apparently healthy subjects per case, matched for sex, age (plus or minus 5 years) and residing within a perimeter of 200 m of the house with the case, and willing to be interviewed, were recruited as the controls. Information on socio-economic indicators, smoking, drinking, diet and screening history in the form of visits to the dentist were collected by personal interview with the subjects. Odds ratio (OR), with 95% confidence intervals (CI), of being diagnosed with an advanced oral cancer, in relation to the screening experience at the date of diagnosis of case, 1, 2, 3, 6, and 12 months prior to the date of diagnosis of case were estimated by conditional logistic regression for matched data. The odds ratio of advanced oral cancer associated with screening in relation to screening experience 3 months prior to the diagnosis of the case was 0.67 (95% CI: 0.46-0.95). The odds ratio was 0.91 (95% CI: 0.60-1.37) for a single screening test and 0.41 (95% CI: 0.24-0.68) for two or more tests. The protection offered by screening persisted up to 3 years since the last test. The results of a descriptive evaluation of the programme also revealed limited evidence towards a shift from advanced to early stages after the introduction of the programme. Nonetheless, the results should be interpreted with caution in view of the several limitations in the study, particularly the fact that screening history was established indirectly by interviews and advanced oral cancers constituted the cases, rather than those who died from the disease.

An evaluation of the oral cancer control program in Cuba.

The Cuban oral cancer screening program, functioning since 1984, requires all subjects of > or = 15 years to have an annual oral visual inspection by dentists. It covered 12-26% of the target population annually. Less than 30% of the subjects with suspect lesions complied with referral. The program identified 16% of the 4,412 incident oral cancers in Cuba during 1984-1990. The proportion of stage I cases increased from 24% in 1983 to 49% in 1990, although staging information was available only for half of the cases. There was no change in oral cancer incidence and mortality in Cuba over the last decade that could be ascribed to the screening program.