EN
Using imunohistochemical technique, localisation and intensity of COX2 expression were estimated in canine soft tissue fibrosarcomas. The obtained results were related to tumour grade of malignancy. The material was sampled in the course of surgery from 23 dogs of various breed, 5 to 18 years of age. The presence of COX2 was demonstrated in cell cytoplasm in over 43% tumours. Augmented expression of COX2 was observed in samples of tumours manifesting higher grade of malignancy. Also strong positive correlation was detected (r=0.76) between expression of COX2 and grade of malignancy in the tumours, which might point to the involvement of the enzyme in neoplastic transformation of the cells from which fibrosarcomas derive in dogs.