Abstract

For the morphological analysis of DMBA (9,10-diemethyl-1,2-benzanthracene) induced tumor, thirty Sprague-Dawley rats were received 0.1 ml of a 2% paraffin solution of DMBA into the knee joint cavity, which was repeated three times at an interval of 4 weeks. The induced tumor masses were removed at the 12th week after the first injection. Histological and histochemical examinations (H & E, PAS, alcian blue, Van Gieson, prussian blue, reticulin, PTAH stain) and enzyme histochemical examinations (acid phosphatase, alkaline phosphatase, alpha-naphthyl acetate esterase) were performed. The results were as follows: 1) By the 12th week after the first injection of DMBA, the tumor incidence rate was 20 percent. 2) On histological and histochemical examination, most of the induced tumor disclosed the features of the fibrous histiocytoma originating from mesenchymal cells, and the remains sweat gland adenoma and adenocarcinoma originating from epithelial cells. 3) On enzyme histochemical examination, most of the mesenchymal cell-derived tumor cells showed positive reactions for acid phosphatase and alpha-naphthyl acetate esterase, which were similar characteristic features of enzyme stains as shown in the component cells of fibrous histiocytoma.

• Keywords: DMBA;Knee joint tumors;Rat