Ductal carcinoma in situ

The natural history of ductal carcinoma in situ (DCIS) is poorly defined. Screening mammography has increased detection, but we cannot identify cases that will not progress to invasive carcinoma. Genomics is promising, but prospective studies with long-term follow-up are needed before concluding that a subset of DCIS is clinically insignificant. The varying intensity of treatments for DCIS reflects uncertainty about its natural history and differing values regarding the impact of local recurrence. The extent of DCIS mostly determines use of a breast-conserving approach, and contraindications to its use and to the use of irradiation have been defined. Clinical decision-making in DCIS would benefit from improved ability to inform patients about long-term risks and benefits of therapy, and to involve them in decision-making.