High-risk groups of patients with Stage II colon carcinoma

Background: It is unclear whether patients with Stage II colon carcinoma should be offered adjuvant chemotherapy. Therefore, the authors analyzed the risk factors of these patients to identify high-risk subgroups who may benefit from such treatment.

Methods: The data from 305 patients with Stage II colon carcinoma documented in the Erlangen Registry of Colorectal Carcinoma were analyzed to identify risk factors for distant metastasis and disease-related survival. The patients 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 patients with Stage II colon carcinoma from the German Study Group for Colorectal Carcinoma (SGCRC).

Results: Emergency presentation, a primary tumor site in the left colon, pT3 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 factors for Stage II colon carcinoma. On dividing patients into subgroups according to these risk factors, it was found that patients in the high-risk group had a significantly higher risk of distant metastases and a significantly lower disease-related survival rate compared with patients in the low-risk group. On analyzing the SGCRC data, the authors also found a significantly 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 to identify a high-risk group of patients who may be candidates for adjuvant chemotherapy. Stratification by the risk factors emergency presentation, tumor site, depth of tumor invasion, and surgical department should be employed in further clinical studies.