Original Contributions: PDF OnlyClinical significance of ras p21 overexpression for patients with an advanced colorectal cancerMiyahara, Masaki M.D.1; Saito, Takao M.D.1; Kaketani, Kazutoshi M.D.1; Sato, Koichi M.D.1; Kuwahara, Akihiko M.D.1; Shimoda, Katsuhiro M.D.1; Kobayashi, Michio M.D.1 Author Information 1Department of Surgery I Medical College of Oita 1-1 Idaigaoka Hasamamachi, Oitagun 879-56 Oita Japan Diseases of the Colon & Rectum: December 1991 - Volume 34 - Issue 12 - p 1097-1102 doi: 10.1007/BF02050069 Buy Metrics Abstract The expression of ras oncogene product p21 was examined in 45 paraffin-embedded sections of primary advanced colorectal cancers, using the anti-v-H-ras p21 monoclonal antibody Y13-259. Fourteen of these specimens (31 percent) were stained positively. The incidence of lymphatic vessel invasion of cancer cells and lymph node metastasis correlated statistically with the overexpression of ras p21. The depth of invasion and incidence of liver metastasis in the p21-positive group were more prominent than in the p21-negative group. Statistically significant differences were evident in operative curability and clinical stage at initial surgery and in the longterm survival rate between these groups (P<0.05). We propose that ras p21 overexpression may serve as a marker to predict the prognosis of colorectal cancer. © The ASCRS 1991