Evaluation in liquid-based versus conventional cytology in the public heal the program

• Grant number: 09/53133-2
• Support Opportunities: Research Grants - Research in Public Policies for the National Health Care System (PP-SUS)
• Start date: July 01, 2010
• End date: June 30, 2012
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Agreement: CNPq - PPSUS
• Principal Investigator: Celso di Loreto
• Grantee: Celso di Loreto
• Host Institution: Instituto Adolfo Lutz (IAL). Coordenadoria de Controle de Doenças (CCD). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

The uterine cervical cancer still remains a major problem of public health in Brazil, although investments in the government program of uterine cancer prevention has grown in the last years. The conventional Pap method widely employed in the Brazilian public health program shows, according to the literature, high specificity (98%), but low sensitivity, around 51%. One of the major drawbacks is related to the specimen collection and slide preparation creating a sort of artifacts that interferes in the slide examination and lead to high percentage of inconclusive diagnosis. The external quality assurance program of cervical cytology of the laboratories related to the SUS of the São Paulo state performed by the Instituto Adolfo Lutz and Fundação Oncocentro since the year of 2000 have pointed a very high inadequate rate in the last years. The problem of high inadequate rates is mentioned in other studies. In order to solve this problem the liquid based cytology was introduced. In this new system the cells removed from the cervix are collected in a fixative fluid and sent to the laboratory to prepare the slides. According to the literature this system lowers the percentage of inadequate smears and allows the use of the residual sample to perform molecular tests and prepare another slide. Studies about better sensibility are not in fully agreement. Some difficulties have delayed the implantation of the new system in the Brazilian public screening program. The most important are the cost and the need of additional investments in the laboratory equipment. However, few studies have been made in Brazil evaluating advantages and drawbacks of the new method in the public health system, all of them with a small casuistic. The aim of this study is to compare the inadequate rates of conventional cytology and the liquid based system in 10,000 consecutive cervical samples collected m women in the region of the Vale do Ribeira in São Paulo state. Additionally, it will be evaluated the eventual decrease in the workload to screen the slides, and the possibility of using the residual sample for teaching slide libraries. (AU)