Cribriform Carcinoma of the Breast

Definition

Irregular cribriform growth pattern
- Round and angular masses of cells embedded in desmoplastic stroma
- Sharply punched out round spaces
- Tubular carcinoma has same behavior so may constitute more than 10%
  - Report mixtures of these two simply as the predominant type
Nuclear grade I in at least 90% of cells
- Slightly enlarged cells
- Uniform nuclei, inconspicuous nucleoli, uniform chromatin
- Pleomorphism minimal or absent
- Mitotic figures unusual
- Remaining 10% must not show nuclear grade III
  - Behavior may be that of the high grade component
  - Report such tumors as mixtures of two types
Myoepithelial cells absent on immunohistochemical stains

Richard L Kempson MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting:: May 1, 2006