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Ductal carcinoma in situ (DCIS) is a non-invasive breast malignancy where neoplastic epithelial cells are confined within the ductal-lobular system, without invasion of the basement membrane.
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It is considered a precursor lesion to Invasive ductal carcinoma (IDC) and accounts for approximately 20–25% of screen-detected breast cancers.
DCIS progression. Progressive stages of breast tissue transformation: starting with normal ductal epithelium, followed by ductal carcinoma in situ (DCIS) characterized by abnormal epithelial proliferation confined within the duct, then DCIS with microinvasion showing early cancer cell escape into the surrounding stroma, and finally, invasive ductal carcinoma (IDC), where malignant cells have fully breached the basement membrane and infiltrated the adjacent tissue.
Prajzendanc K. DCIS Progression and the Tumor Microenvironment: Molecular Insights and Prognostic Challenges. Cancers. 2025; 17(12):1925. https://doi.org/10.3390/cancers17121925
| Grade | Features |
|---|---|
| Low-grade | Small, uniform cells; slow-growing; often ER+/HER2– |
| Intermediate-grade | Mixed features; variable atypia |
| High-grade | Large, pleomorphic cells, necrosis, comedonecrosis common; often HER2+ |
Architectural Patterns: