Objective: To build a model that explains the natural history of breast cancer diagnostic procedures.
Methods: Descriptive cross-sectional study of 245 women between 40 and 69 years of age, selected by simple random sampling, who underwent a mammography and met the requirements of the breast cancer diagnostic procedure. Diagnosis was made by biopsy. For the diagnostic procedure, an estimate was made of the percentage of patients seen by each service, the total number of patients per service, and the total number of consultations in each service, with 95% confidence intervals.
Results: Of the patients who initiated the breast cancer diagnostic procedure in preventive medicine services, 20% underwent a mammography; 23.7% were seen in family medicine services and of these patients, 70.9% were referred to a breast clinic, where 7.3% underwent a harpoon biopsy. The prevalence of breast cancer confirmed by biopsy was 0.48% (95%CI: 0.0-1.3). Per 1 000 patients who initiated the procedure, 47.4 were seen in family medicine services and 33.6 in a breast clinic, and open biopsies were performed on 2.4. Per 1 000 patients who initiated the procedure, there were 211.4 consultations in radiology services, 51.6 in family medicine services, and 54.6 in a breast clinic.
Conclusions: The model described here may be useful in planning and evaluation activities.