Frozen section examination of a representative sample diagnosed poorly differentiated invasive carcinoma. An axillary dissection was performed. Multiple sections of the neoplasm revealed a histopathology similar to that seen in the aspiration biopsy. The diagnosis of a poorly differentiated carcinoma is supported by the presence of large malignant epithelioid cells with a tendency to form ducts and occasional nests surrounded by lymphocytes admixed with plasma cells, seen in Figures 1 and 2. Necrosis was marked, there was no evidence of squamous metaplasia.
Metachromatic matrix separates the neoplastic cell clusters.
Abnormal mitotic figures were numerous. Also prominent are numerous bizarre, sometimes spindle-shaped nuclei with coarsely clumped chromatic material. These are represented in Figures 3 and 4. Tumor giant cells of varied sizes and shapes are also seen, Figures 3 and 5. No cartilage or bone formation is evident.