Which prognostic factors are important for long-term outcomes in symptomatic obstructive colon cancer? A multi-institutional retrospective cohort study

PURPOSE: The prognostic factors in obstructive colon cancer have not been clearly identified. We aimed to identify the prognostic factor to establish optimal treatment strategy in obstructive colon cancer. METHODS: Patients who underwent surgery for primary colon cancer in stages II and III with symptomatic obstruction from 2004 to 2010 in six hospitals were retrospectively collected. Clinicopathological and surgical outcomes were compared between stent insertion and emergent surgery group. Multiple regression analysis and survival curve analysis were used to identify the prognostic factors in symptomatic obstructive colon cancer. RESULTS: Among 210 patients, 168 patients (80.0%) underwent stent insertion followed by surgery and 42 patients (20.0%) underwent emergent surgery. Laparoscopic approach (55.4% vs. 23.8%, p < 0.001) and adequate lymph node (LN) harvest (≥12) (93.5% vs. 69.0%, p < 0.001) were significantly higher in stent insertion group. In multiple regression analysis, emergent surgery (hazard ratio [HR], 2.153; 95% confidence interval [CI], 1.031–4.495), vascular invasion (HR, 6.257; 95% CI, 2.784–14.061), and omitting adjuvant chemotherapy (HR, 3.107; 95% CI, 1.394–6.925) were independent poor prognostic factors in 5-year overall survival, and N stage (N1 HR, 3.095; 95% CI, 1.316–7.284; N2 HR, 4.156; 95% CI, 1.671–10.333) was the only poor prognostic factor in 5-year disease-free survival. CONCLUSION: In symptomatic obstructive colon cancer, emergent surgery, N stage, vascular invasion, and omission of adjuvant chemotherapy were independent poor prognostic factors. Stent insertion is suggested as the initial treatment for symptomatic obstructive colon cancer, and adjuvant chemotherapy is recommended, especially when vascular invasion or LN metastasis is confirmed.