Immunohistochemical properties of ocular adenomas, adenocarcinomas and medulloepitheliomas

• Published in: Veterinary ophthalmology Vol. 9; no. 6; pp. 387 - 394
• Main Authors: Klosterman, E, Colitz, C.M.H, Chandler, H.L, Kusewitt, D.F, Saville, W.J.A, Dubielzig, R.R
• Format: Journal Article
• Language: English
• Published: Malden, USA Malden, USA : Blackwell Publishing Inc 01.11.2006; Blackwell Publishing Inc
• Subjects: adenocarcinoma; Adenocarcinoma - diagnosis; Adenocarcinoma - immunology; Adenocarcinoma - veterinary; adenoma; Adenoma - diagnosis; Adenoma - immunology; Adenoma - veterinary; animal diseases; Animals; Antibodies; antibody detection; biomarkers; Biomarkers, Tumor - immunology; canine; ciliary body epithelium; cytokeratins; differential staining; disease detection; disease diagnosis; Dog Diseases - diagnosis; Dog Diseases - immunology; Dogs; epithelium; eye diseases; Eye Neoplasms - diagnosis; Eye Neoplasms - immunology; Eye Neoplasms - veterinary; eyes; Female; immunohistochemistry; Immunohistochemistry - veterinary; keratin; Male; medulloepithelioma; neoplasms; Neuroectodermal Tumors, Primitive - diagnosis; Neuroectodermal Tumors, Primitive - immunology; Neuroectodermal Tumors, Primitive - veterinary; Predictive Value of Tests; RNA-directed DNA polymerase; telomerase; telomerase reverse transcriptase; telomerase reverse transcriptase (TERT); veterinary medicine
• ISSN: 1463-5216; 1463-5224
• DOI: 10.1111/j.1463-5224.2006.00478.x

Ocular medulloepitheliomas, adenomas and adenocarcinomas share a common phenotype and originate from the optic cup neuroectoderm. This can make it very difficult to differentiate between these tumors histopathologically. Therefore, this study focused on identifying a combination of immunologic markers that might be used in the diagnosis of these tumors. These markers included AE1/AE3, CK7, CK20, and telomerase reverse transcriptase (TERT). Routine immunohistochemical staining was performed on 27 whole globes diagnosed with one of these tumors. The tumors that immunostained for TERT showed increasing immunoreactivity as the tumor types increased in aggressiveness. None of the tumor types were immunopositive for CK7. CK20 immunostaining was found in the adenomas but not in the adenocarcinomas or medulloepitheliomas. AE1/AE3 expression was present more consistently in the adenocarcinomas and less frequently in the adenomas. AE1/AE3 expression was present in only one of six medulloepitheliomas. Furthermore, CK20 and TERT showed inverse expression patterns, i.e. TERT increased in expression and CK20 decreased in expression with increasing aggressiveness. These results may be important diagnostic and prognostic indicators for these tumors.