Ductal Carcinoma In Situ—Pathological Considerations

Abstract

Mammographic screening and radiological surveillance for local management has led to an exponential increase in diagnosis of ductal carcinoma in situ (DCIS) with limited impact on breast cancer specific mortality. Since definitive diagnosis of DCIS requires histopathological examination increase in radiological surveillance has resulted in significant increase in breast biopsies. Pathological characteristics of DCIS include grade, necrosis, size, anatomy, margins of excision, estrogen, and progesterone receptor status, and these features are useful for both prognostication and prediction. Differential diagnosis of DCIS extends from atypical ductal hyperplasia to micro-invasive carcinoma and increasingly pathologists recognize intraductal lesions at the borderline between atypical ductal hyperplasia and ductal carcinoma in situ. Clinicopathological characteristics of DCIS continue to be significant in prospective trials and have been integrated with predictive molecular tools. Since most cases of DCIS do not progress to invasive cancer multiple tools which include clinicopathologic and molecular signatures are in the process of development and validation for personalizing treatment strategies for patients. Ongoing clinical trials are testing whether DCIS with favorable clinicopathologic characteristics may avoid loco-regional therapy which typically includes breast conserving surgery and radiotherapy.