橋本 洋¹, 松村 道明², 斉藤 恵一², 内山 明彦², 小幡 裕¹

Hiroshi HASHIMOTO¹, Michiaki MATSUMURA², Keiichi SAITO², Akihiko UCHIYAMA², Hiroshi OBATA¹

¹東京女子医科大学消化器病セン夕ー内科, ²早稲田大学理工学部

¹Department of Internal Medicine, Institute of Gastroenterology Tokyo Womens' Medical College, ²School of Science and Engineering, Waseda University

キーワード : Low gray-level areas, Density of gastric cancer cell

We studied the tissue characterization of gastric cancer echoes, with attention to the low gray-level areas. We investigated low gray-level areas in gastric cancer echoes and supposed the low gray-level of gastric cancer echoes to reflect masses of gastric cancer cells, judging the homogenous low-echo area in the medullary type of gastric cancer echo. We selected three-seven regions of interest (ROI, 10×10 pixeles) on gastric cancer echo in each case, and we calculated the percentage of low gray-level pixels in the ROI (P(LGL)). The low gray level was determined to be under 45/256 in cases of medullary and intermediate cancer, and was determined to be under 65/256 in cases of gastric cancer cases with fibrosis. We evaluated percentage of low gray level pixels on ROI in each case by variance analysis. On the other hand, we calculated density of gastric cancer cells of resected specimens under high magnification. As a result, P (LGL) was related to density of gastric cancer cells in each case. We concluded that low echo areas of gastric cancer echo reflected masses of gastric cancer cells. This method might be useful for diagnosing the depth invasion of gastric cancer with fibrosis.