[Characterization of oncological disease: racional, objectives and methodology - perfil study].

Oncologic disease is one of the main causes of death in Portugal, as well as a high morbidity rate. Over the past few years, these diseases have been targeted with several strategies which aims at optimizing the use of available therapeutic and diagnostic options. Nevertheless, the amount of quantitative information available regarding the disease, patient profile, and treatment and monitoring practices is very low. In order to optimise the implementation of health policies specifically directed at oncologic diseases reliable and up-to-date information is needed, permitting optimisation and balancing of costs and benefits. The PERFIL national epidemiologic study is a multi-centre, retrospective cohort study which aims at evaluating the clinical practice regarding treatment of 6 neoplasias -colorectal, gastric, breast, prostate, lung, and lymphoma, in Portugal, between 2003 and 2007. This study is based upon data collection from the clinical files of patients being followed in the participating centres from 2003 to 2007. Qualitative evaluation (diagnosis and stage) was collected from the clinical records of all patients seen in each participating centre on a given month in each year from 2003 to 2007. The characterization of both patient profile and treatment and monitoring patterns will be based on a far-reaching analysis of 10,000 of those files, selected in a random and stratified sampling. This article describes the PERFIL study rationale, its objectives, and methodology.