Colorectal obstruction is a potential prognostic factor for stage II colorectal cancer.

BACKGROUND

Obstructive colorectal cancer (CRC) is an emergency situation with high morbidity and mortality, but long-term outcomes of stage II/III obstructive CRC remain unclear. The aim of this study was to evaluate prognostic factors, including colorectal obstruction.

METHODS

Data were retrospectively reviewed from consecutive patients with stage II/III CRC who underwent curative surgery between January 2007 and December 2011 at two Japanese institutions. We analyzed overall survival (OS) and relapse-free survival (RFS), according to various prognostic factors including colorectal obstruction.

RESULTS

In total, 979 patients with stage II/III CRC were identified for this study. Among these 979 patients, 94 patients showed colorectal obstruction (9.6%). In both stage II and stage III CRCs, colorectal obstruction showed significantly poorer OS and RFS compared to non-obstruction (5-year OS, obstruction vs. non-obstruction, stage II: 65.9 vs. 86.5%, P = 0.002; stage III: 55.9 vs. 73.6%, P = 0.007) (5-year RFS, obstruction vs. non-obstruction, stage II: 59.2 vs. 77.8%, P = 0.008; stage III 31.3 vs. 56.3%, P = 0.001). Multivariate analysis demonstrated colorectal obstruction as a significant independent and poor prognostic factor in terms of both OS (hazard ratio (HR) 2.469; 95% CI 1.339-4.545; P = 0.004) and RFS (HR 1.992; 95% CI 1.160-3.425; P = 0.012) for stage II CRC, as well as pT4 stage. On multivariate analysis for stage III CRC, colorectal obstruction was a significant predictor of poor RFS (HR 1.626; 95% CI 1.070-2.469; P = 0.023), but not poor OS.

CONCLUSIONS

Colorectal obstruction is an independent poor prognostic factor for stage II CRC. Adjuvant chemotherapy might be feasible for stage II CRC with colorectal obstruction.