Infiltrating Ductal Carcinoma of the Breast (Carcinoma of No Special Type)
Definition
- Invasive adenocarcinoma demonstrating differentiation characteristic of breast ductal cells
- Includes all carcinomas not designated as an otherwise recognizable type
Diagnostic Criteria
- Irregular infiltration of stroma
- Variable ductal formation by infiltrating cells
- Wide range of cytologic atypia and mitotic rates
- Typical cases express e-cadherin
- Myoepithelial cells absent in invasive areas
- Infiltrating carcinoma should be separated from DCIS with minimal stromal invasion (microinvasion)
