Carcinoma obstruction of the proximal colon cancer and long-term prognosis-obstruction is a predictor of worse outcome in TNM stage II tumor

Purpose: Colon obstruction is suggested to be a predictor of poor outcome in colon cancer. However, the effect of obstruction on outcome in patients with different tumor-nodes-metastases (TNM) stage cancer has not been fully addressed. The aim of this study is to determine whether colon obstruction predicts surgical and long-term oncologic outcomes in patients with proximal colon cancer. Methods: A total of 1,492 consecutive patients underwent open resection of primary adenocarcinoma of right colon in a single institution between January 1995 and December 2005. Clinical and follow-up data were extracted from a prospective colorectal cancer database. Univariate and multivariate analyses were performed to identify colon obstruction and other predictors of surgical and oncologic outcomes. Results: Among 1,492 patients, 306 (20.5%) patients presented with colon obstruction. The rates of surgical morbidity and mortality were greater in patients with an obstruction as compared to patients without an obstruction (22.2% and 3.9% vs. 14.1% and 1.9%; p=0.0005 and 0.041, respectively). Obstruction predicted a worse long-term disease-free survival (DFS) among patients with stage II-III disease (log-rank test, p=0.0003). The data were stratified by TNM stage. Obstruction predicted a worse DFS among patients with TNM stage II cancer (598 patients; log-rank test, p=0.001; Cox regression, p=0.012), but it was not a predictor in TNM stage III cancer patients (424 patients; p=0.116; p=0.108). Conclusions: Colon obstruction was an independent predictor of long-term outcome only in TNM stage II but not in stage III proximal colon cancer. Patients with TNM stage II obstructive colon cancer could be included in future trials of adjuvant therapies.