Immunocytochemical detection of Ki‐67 in Diff‐Quik‐stained cytological smears of canine mammary gland tumours |
| |
Authors: | U. S. Choi D. Y. Kim |
| |
Affiliation: | 1. Department of Veterinary Clinical Pathology, College of Veterinary Medicine, Chonbuk National University, Duckjin Dong, Duckjin gu, Jeonju, South Korea;2. Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, Seoul, South Korea |
| |
Abstract: | U.S. Choi and D.Y. Kim Immunocytochemical detection of Ki‐67 in Diff‐Quik‐stained cytological smears of canine mammary gland tumours Objective: To investigate whether Diff‐Quik stained fine needle aspirate smears can be used to evaluate Ki‐67 expression by immunocytochemistry. Methods: Both cytological and histological samples were obtained from 24 dogs with spontaneously developed mammary gland tumours. The cytological and histological specimens were examined by Diff‐Quik and H&E stains, respectively. After examination, both samples were immunostained using the same Ki‐67 antibody. The % Ki‐67 values were calculated based on the percentage of positively stained tumour cells per 500 and 1000 tumour cells in cytology and histology specimens, respectively. Results: Ki‐67 staining was successful in 17/24 smears (71%) and 19/23 sections (83%). The correlation coefficient between the percentage of Ki‐67‐positive cells in cytological smears and in the histological sections was 0.677 (P < 0.01). These values were significantly different between histologically benign and malignant tumour groups both in cytology and histology samples (P < 0.001). The threshold value of the percentage of Ki‐67‐positive cells for distinguishing benign from malignant tumours was set at 4.85% with 90.9% sensitivity and 92.3% specificity by Receiver Operating Characteristic (ROC) curve using histopathology as the gold standard. Conclusion: Diff‐Quik‐stained cytology smears can be used to detect the presence of Ki‐67 antigen when histology sections are not available. |
| |
Keywords: | Ki‐67 Diff‐Quik fine needle aspiration cytology smear histology immunocytochemistry canine mammary tumours |
|
|