RESUMO
BACKGROUND & OBJECTIVE: Most of the studies on lymphatic metastasis mechanism of carcinoma are confined to distribution of lymphatics. This research was to observe distribution and morphologic features of the lymphatics in periphery region of carcinoma, and morphologic changes of lymphatic endothelia. METHODS: Specimens were obtained from 10 patients with gastric carcinoma and 10 patients with colon carcinoma; 20 mice models bearing colon carcinoma were established. Morphology of lymphatics and ultrastructure of lymphatic endothelia were observed under microscope. Number density and volume density of lymphatics in periphery region of carcinoma and normal region were measured using computer image analysis system; open rate and destructive rate of lymphatics were calculated. RESULTS: The lymphatics in periphery region of carcinoma were dilated; their walls were disintegrated. Lymphatic endothelia were dissolved and destroyed into broken fragments; the organellae showed pathologic changes. Number density and volume density of lymphatics were significantly higher in periphery region of colon carcinoma than in normal region [(10.2+/-1.7)/mm(2) vs. (5.1+/-0.8)/mm(2), P < 0.05û (1.5+/-0.2)% vs. (0.7+/-0.0)%, P < 0.05], and were significantly higher in periphery region of gastric carcinoma than in normal region [(8.0+/-0.9)/mm(2) vs. (3.4+/-0.6)/mm(2), P < 0.01; (1.6+/-0.3)% vs. (0.8+/-0.2)%, P < 0.05]. Open rate of lymphatics was significantly higher in periphery regions of mice model colon carcinoma, human gastric carcinoma, and colon carcinoma than in relevant normal regions (22.2% vs. 7.8%, 35.0% vs. 8.0%, and 25.8% vs. 5.0%, P < 0.05). Destructive rate of lymphatics was significantly higher in periphery regions of mice model colon carcinoma, and human gastric carcinoma than in relevant normal regions (20.1% vs. 0, and 35.3% vs. 2.0%, P < 0.05). CONCLUSION: Compare with the lymphatics in normal tissue, the lymphatics in periphery region of carcinoma tissue are dilated with disintegrated walls; the lymphatic endothelia are destroyed; the density of the lymphatics is increased.