BREAST CYTOPATHOLOGY

Special Types of Breast Carcinomas 111
• Tumors contain epithelial fragments, usually cohesive, with
a prominent tubular architecture.
• Tubules have rigid walls, and the lumen is often open ended
with frequent scalloping or right-angle branching.
• Glands have comma-shaped morphology.
• There is minimal atypia and nuclear monomorphism.
• Occasionally, background myoepithelial nuclei are present.
• Fibrous tissue fragments are often densely collagenized.
Pitfalls and Differential Diagnosis
• Fibroadenoma
• Benign ductal epithelium (such as in adenosis)
Medullary Carcinoma
Clinical Features
• Special type of tumor with syncytial sheets of pleomorphic
cells, increased mitoses, lymphocytic infiltrate
Figure 4.30. Tubular carcinoma. Tightly cohesive fragments of
carcinoma with a prominent tubular morphology. Note the
lack of any background cells, including red blood cells. (Smear,
Papanicolaou.)