Ductal carcinoma in situ (DCIS) is a heterogeneous disease that progresses to invasive cancer in 30-50% of the patients. Its natural history is poorly defined so that we are unable to identify cases of DCIS that do not progress to invasive carcinoma during an individual's lifetime. However, pathologic features of DCIS are nowadays the basis for the estimation of the prognosis and planning of therapy. Exclusion of microinvasion, characterization of nuclear grade, architecture, size and distribution of the DCIS, presence or absence of comedonecrosis as well as the assessment of surgical margins are relevant factors for local treatment. The determination of steroid hormone receptor status is indicated in patients considering tamoxifen therapy after breast conservation. It is advisable to evaluate the features according to internationally accepted guidelines with proven prognostic relevance and reproducibility. Nevertheless, better prognostic factors are needed to adapt the management of this increasingly diagnosed disease to the individual patient.
