Demonstrability of the glycoprotein A-80 in postradiation prostatic carcinoma

Radiation therapy results in significant morphological changes in prostatic carcinoma, including decreased cancer size, acinar shrinkage and distortio n, cytoplasmic vacuolization, and nuclear pyknosis. Benign acini usually di splay enlarged, atypical cells with hyperchromatic nuclei. These changes co nfound the evaluation of limited postradiation samples. The glycoprotein A- 80 is known to be upregulated in prostatic intraepithelial neoplasia (PIN) and prostatic carcinoma. In this study, we assessed the expression of A-80 in radiation-treated prostatic carcinoma. Paraffin sections from 64 postrad iation prostatic carcinomas obtained at salvage prostatectomy were immunost ained with a monoclonal antibody to A-80; selected sections were doubly imm unostained with antibodies to A-80 and various cytokeratin polypeptides. Al l cases showed readily detectable and often intense staining in the cytopla sm of cancer cells and in intraluminal material of malignant acini. The ext ent and intensity of the reactions were independent of cancer size and grad e. Strong reactions were seen in preserved and distorted acini, dear fell a reas, single cancer cells, and in colloid pools with few or no recognizable cancer cells. PIN was present in 34 cases (53%), of which 27 (79%) stained strongly for A-80; atrophic and hyperplastic acini generally did not stain , irrespective of the degree of cellular atypia. The A-80 glycoprotein appe ars remarkably durable and is readily demonstrable in postradiation prostat ic carcinoma despite profound architectural and cytologic changes. This cha racteristic may prove useful in evaluating small samples for confirmation o f diagnosis and determination of extent of residual or recurrent prostatic carcinoma after radiation therapy. Copyright (C) 1999 by W.B. Saunders Comp any.