Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.

Definition of Intraductal carcinoma

Medically reviewed by Min Clinic Staff | Updated: January 2026

Intraductal carcinoma: A condition characterized by the proliferation of malignant cells in the lining of a breast duct without evidence of spreading outside the duct to other tissues in the breast or outside the breast. Also known as ductal carcinoma in situ, abbreviated DCIS. DCIS is clearly a precursor (forerunner) of invasive breast 'cancer. DCIS originates in a single glandular structure but may spread within the breast through the ductal system. The goal in treating DCIS is to prevent local recurrence and, in particular, invasive breast cancer.