Breast cancer metastases.

Histology:

 MACROSCOPIC DESCRIPTION:
1. "Brain tissue": Red and pale tan tissue 15 x 5 x 4 mm.  FROZEN SECTION DIAGNOSIS: Metastatic carcinoma. 
2. "Brain tissue": Three fragmented pieces of brain tissue 7-45 x 40 x 25 mm with attached dura. 
3. "Dura": A sheet of pale tan tissue 80 x 10 x 1 mm.  
 

MICROSCOPIC DESCRIPTION:
1. Sections show fragments of cortex infiltrated by cohesive tumor nests and glands with cribriform architecture and some central necrosis. Tumor cells are epithelial with large markedly pleomorphic nuclei.
2. Sections show tumor of similar appearance to specimen 1 infiltrating brain parenchyma and dense fibrous tissue. By immunohistochemistry, the tumor cells are positive for AE1/3, CK7 and GATA3 and negative for CK20. INVASIVE CARCINOMA IMMUNOHISTOCHEMISTRY: ER -positive, 2+, 20 %PR -negative, 0, 0 %HER2 -positive, 3+
3. Sections show strips of dura with focal meningothelial hyperplasia. There is no tumor identified.

DIAGNOSIS:

1. brain tissue: metastatic breast carcinoma
2. brain tissue: metastatic breast carcinoma
3. dura: dura with reactive changes