Vol. 11, Special Issue 5 (2022)

Author(s):
Dr. K Rama Krishna, Dr. M Jeevana Latha, Dr. M Lakshman, Dr. M Usha Rani, Dr. Y Ravi Kumar and Dr. B. Swathi

Abstract:
In the present study 21 Canine mammary tumor (CMT) samples were collected from Department of Veterinary Surgery and Radiology, College of Veterinary Science, Rajendranagar and from various Veterinary clinics in and around Hyderabad. The CMT samples were collected in 10 per cent neutral buffered formalin (NBF) for the histopathology and immunohistochemistry and Tumour tissues were processed by routine paraffine embedding method. H & E staining was performed and tumours were classified based on descriptive morphology and histogenesis. Proliferation kinetics were studied with immunohistochemistry using PCNA and Ki-67 antibodies with a view to use the techniques in differentiating benign and malignant tumours. IHC was carried out on paraffin sections mounted on poly L-lysin coated slides and mean number of positive cells were counted and the values were subjected to standard statistical methods and results were drawn. Out of 21 CMTs studied 16 (77.20%) were malignant and 5 (23.80%) were benign. Out of 16 malignant tumours malignant mixed mammary tumours (25%) were seen predominantly followed by papillary adenocarcinoma (18.75%), tubular adenocarcinoma (12.5%), solid carcinoma (12.5%), cavernous hemangionma (12.5%), squamous cell carcinoma (6.25%), papillary cystic adenocarcinoma (6.25%), fibrosarcoma (6.25%). Out of 5 benign tumours lipoma (40%), soft tissue hyperplasia (40%) were predominantly seen followed by fibroadenoma (20%). The mean PCNA positive nuclei in different tumour tissues varied from 3.24±0.06 to 52.35±7.27. The highest index was observed in solid carcinomas and the lowest index was observed in soft tissue hyperplasia. The mean number of PCNA positive nuclei in benign tumours (5.42±1.48) was significantly (P<0.05) lower than the malignant tumours (39.45±3.84). The mean Ki-67 positive nuclei in different tumour tissues varied from 1.04±0.06 to 47.7±5.26. The highest index was observed in Malignant mixed mammary tumor and the lowest index was observed in soft tissue hyperplasia. The mean number of Ki-67 positive nuclei in benign tumours (6.25±1.51) was significantly (P<0.05) lower than the malignant tumours (32.95±3.16). In conclusion high PCNA and Ki-67 counts were associated with malignancy.