High-risk groups of patients with stage II colon carcinoma

BACKGROUND. It is unclear whether patients with Stage Il colon carcinoma sh ould be offered adjuvant chemotherapy. Therefore, the authors analyzed the risk factors of these patients to identify high-risk subgroups who may bene fit from such treatment. METHODS. The data from 305 patients with Stage II colon carcinoma documente d in the Erlangen Registry of Colorectal Carcinoma were analyzed to identif y risk factors for distant metastasis and disease-related survival. The pat ients were divided into two subgroups: those in a low-risk group and those in a high-risk group. The data were then compared with those from 306 patie nts with Stage II colon carcinoma from the German Study Group for Colorecta l Carcinoma (SGCRC). RESULTS. Emergency presentation, a primary tumor site in the left colon, pT 3 tumors with a depth of invasion of > 15 mm beyond the outer border of the muscularis propria, and pT4 lesions were identified as the major risk fact ors for Stage Il colon carcinoma. On dividing patients into subgroups accor ding to these risk factors, it was found that patients in the high-risk gro up had a significantly higher risk of distant metastases and a significantl y lower disease-related survival rate compared with patients in the low-ris k group. On analyzing the SGCRC data, the authors also found a significantl y higher rate of distant metastases in the high-risk group, but the disease -related survival rate differed only marginally. CONCLUSIONS. Among patients with Stage II colon carcinoma, it is possible t o identify a high-risk group of patients who may be candidates for adjuvant chemotherapy. Stratification by the risk factors emergency presentation, t umor site, depth of tumor invasion, and surgical department should be emplo yed in further clinical studies. (C) 2001 American Cancer Society.