MACROSCOPY:
- "Pituitary": A piece of soft tan tissue 3mm. DIAGNOSIS: Pituitary adenoma.
- "Pituitary lesion": Pale pink tissue fragments 5mm in aggregate.
MICROSCOPY: 1&2. Sections show a hypercellular tumour composed of solid sheets, nests and trabeculae. Tumour cells contain scant granular eosinophilic cytoplasm, round nuclei with finely granular chromatin and inconspicuous nucleoli. No mitoses or necrosis are seen. No normal anterior pituitary tissue is included. No brain invasion is seen.
Immunohistochemical results show positive Prolactin and CAM5.2 staining, whilst LH, FSH, GH, ACTH and TSH pituitary hormones are negative. The Topoisomerase proliferation index is 1%.
CONCLUSION: Pituitary tumour: Densely granulated Prolactin secreting pituitary adenoma.