Interval cancer in breast cancer screening program

Abstract

Interval breast cancer has an increasing incidence in our lives because of regular mammography exam. By definition, it corresponds to breast tumors diagnosed in an organized mammographic screening program, where the frequency, age and target population were previously established. Its definition shows the importance of a previous negative mammography, performed on asymptomatic women. It represents about 30% of the tumors found in an organized breast cancer-screening program. The interval cancer may be classified as a true interval tumor, false negative or occult/minimal signs. False negative findings are mainly related to loss of quality in mammography or missinterpretation by the observers. Their knowledge is fundamental in clinical practice, because part of these tumors can be avoided by adopting high standards programs of quality control. It is rarely discussed in Brazilian literature, due to limited experience in multiple rounds of mammographic breast cancer screening, which justifies the discussion and report of different types of interval tumors.