Accuracy of routine cytology and immunocytochemistry in preoperative diagnosis of oral amelanotic melanomas in dogs. (23rd September 2015)

• Record Type: Journal Article
• Authors: Przeździecki, Rafał; Czopowicz, Michał; Sapierzyński, Rafał
• Is Part Of: Veterinary clinical pathology. Volume 44:Number 4(2015)
• Page Start: 597
• Page End: 604
• Publication Date: 2015-09-23
• Subjects: Amelanotic melanomas -- cytology -- dog -- immunocytochemistry -- Melan A -- oral cancers; Veterinary pathology -- Periodicals; 636.089607
• DOI: 10.1111/vcp.12292
• Languages: English
• ISSNs: 0275-6382

Abstract

Abstract : Background: Amelanotic melanomas are one of the most common oral malignancies. The cytologic and histopathologic differentiation between amelanotic melanoma, sarcoma, and poorly differentiated carcinoma is often difficult or even impossible. Objectives: The aim of this study was to assess the reliability of routine cytology and immunocytochemistry in preoperative diagnosis of canine oral amelanotic melanoma. Methods: Cytologic preparations from undifferentiated canine oral tumors were stained with Giemsa and by immunocytochemistry (ICC) using anti‐cytokeratin, anti‐vimentin, and anti‐Melan A antibodies. The final cytologic diagnosis (including ICC) was compared to the final diagnosis based on histopathology and immunohistochemistry (IHC) results, and sensitivity and specificity of cytologic examination were determined. Results: Final cytologic diagnoses of 38 cases agreed well with the histopathologic/immunohistochemical diagnoses, thus both specificity and sensitivity of combined routine cytology and ICC were 100% (95% confidence interval 90.8–100%). Of 32 oral tumors, diagnosis of amelanotic melanoma, sarcoma, and carcinoma was made using routine cytology and ICC. In 4 of 6 aspirates taken from lymph nodes, a preliminary diagnosis of metastatic amelanotic melanoma corresponded with the final diagnosis. Both sensitivity and specificity of routine cytology in diagnosis of amelanotic melanomas were considered moderate (66.7% and 85.7%, respectively). Conclusions: In conclusion, routine cytology is a reliable diagnostic method for canine oral amelanotic melanoma and metastatic amelanotic melanoma, and ICC, using anti‐cytokeratin, anti‐vimentin, and anti‐Melan A antibodies, is an excellent supporting method for presurgical diagnosis of poorly differentiated oral malignancies in dogs.