BREAST CYTOPATHOLOGY

128 4. Primary Malignant Tumors
Figure 4.47. Carcinoma with osteoclastlike giant cells. Irregular
fragments of pleomorphic carcinoma containing numerous multinucleated
giant cells resembling osteoclasts. (Smear, Papanicolaou.)
Pitfalls and Differential Diagnosis
• Fibrocystic changes, papillomatosis
Neuroendocrine Carcinoma
Clinical Features
• Primary neuroendocrine carcinomas of the breast are rare
variants of infiltrating breast carcinoma.
• Neuroendocrine carcinoma represents 2%–5% of all invasive
breast carcinomas.
• Most cases present in the sixth to seventh decade of life.
• Neuroendocrine tumors do not present any differently
than other tumor types.
• Most patients present with a palpable mass.
• On mammography, the tumor nodule is well-circumscribed.
• In general, this type has a very poor prognosis.
• Neuroendocrine tumors include solid neuroendocrine carcinomas,
small cell carcinomas, and large cell neuroendocrine
carcinomas.