Canine Tumors:Diagnosis,Treatment And Expression Of Cyclooxygenase-2

Along with increasing number of canine breeding in our country,the incidence rate of diseases is also rising,especially,canine neoplastic diseases.However,canine neoplastic diseases have not been paid much attention in these years.In order to investigate the epidemiology of canine tumors,we examined 133 cases of the canine tumors from animal hospital of Zhejiang province,Jiangsu province and Shanghai and studied the relationship between tumors and clinical symptoms,species,gender,age and diet,etc.In 56 cases autogenic tumors,these neoplasm were removed by surgical method,and fixed in solution of 4%formaldehyde for HE staining and classified by histopathologyical examination.In addition,we studied the relationship between tumors by expression patterns of Cyclooxygenase-2(COX-2).Among these collected tissues,46 tumors and 5 different kinds of normal tissues of mammary glands,skin,testis,anal glands and uteruses(6 of each)were taken from animal hospital of Zhejiang University.These tissues were examined by immunochemistry S-P staining method to detect the expression rate of COX-2.Our results showed that:1.Through the investigation of 133 cases of autogenic tumors,our results showed that animals with neoplastic disease does not show any general systemic symptoms in the early stages of diseases,but cachexia was invariably observed at metastatic stage.The most common locations of the tumors are:mammary glands(42.11%of the cases),skin and soft tissues(24.81%).The most affected breeds,in decreasing order of frequency,were pekingese(19.55%),hybrids(14.29%),poodle(11.28%),Pomeranian(8.27%)and shih tzu(7.52%).The age of tumor ocurrence extend from 1 to 15 years old,with the most frequent occurrence being in the age group of 6 to 10 years old,and an average of 9.39 years old.The occurrence of the tumors depends also on a daily diet:meat with rice diet shows the highest rate(39.85%),whereas meat plus ham/sausages(26.32%)and dog food plus meet(21.05%)were associated with moderate rate of tumors occurring,and dog food on only daily basis with the lowest rate(12.78%).Other factors that affect neoplastic include gender and the animal’s sterilization conditions.2.56 cases of tumors were removed by surgical method,and our results show that:surgery is the most common treatment method;in the 56 cases,30 cases were malignant,and 26 cases were benign.In accordance with tumors of different tissue types,in 29 cases of mammary glands tumors,21 of them were malignant,including complex carcinoma,tubulopapillary carcinoma,solid carcinoma,anaplastic carcinoma,mucinous carcinoma,fibrosarcoma,osteosarcoma,carcinosarcoma.Benign tumors were found in 8 from these 29 cases,including simple adenoma,complex adenoma,fibroadenoma and hyperplasia of mammary glands.From 12 cases of skin and soft tissue tumors,3 of them were malignant,including sebaceous carcinoma and iliposarcoma.Bening tumors were found in 9 of these 12 cases,including basal cell tumor,fibroma,hemanyiopericytoma,hepatoid gland adenoma,sebaceous epithelioma and trichoblastoma.From 5 cases of the anal glands tumors,3 of them were hepatoid gland carcinoma,another 2 cases were hepatoid gland adenoma,which were benign.From 6 cases of vagina and cervix tumors,3 of them were malignant,including fibrosarcoma and leiomyosarcoma,and 3 cases were benign tumors-leiomyoma.All of the 4 testicular tumors were benign,including sertoli cell tumor and interstitial cell tumor.3.Positive reaction of COX-2 in canine tumours samples expressed mainly in tumor cell’s cellular plasma around the cell nucleus,like brown or yellow particles.In 30 from 46 cases of canine neoplastic diseases,COX-2 demonstrated strong positive expression,and 5 cases have moderate positive expression,the positive expression rate reached to 76.1%(35/46).In the 30 experiments with normal tissues,COX-2 positive expression rate was only 20%(6/30).This data show that the difference of COX-2 expression in tumor-tissues and normal tissues has statistical significance(P<0.05).46 cases of canine tumors were examined by immunochemistry,among the 19 cases of benign tumors,15 of them demonstrated strong positive expression of COX-2,the positive expression rate was 78.95%;among the 27 cases of malignant tumors,15 of them appeared strong positive expression of COX-2,and 5 of these 27 cases have moderate positive expression,the positive expression rate reach to 74.1%.This data indicate that there is no statistical difference of COX-2 expression between malignant and benign tumors(P>0.05).