Prognostic significance of clinical and pathological stages on locally advanced rectal carcinoma after neoadjuvant chemoradiotherapy

OBJECTIVE To investigate prognostic significance of clinical and pathological stages in patients with locally advanced rectal carcinoma treated with neoadjuvant chemoradiotherapy (neo-CRT) and total mesorectal excision. PATIENTS AND METHODS 210 patients with locally advanced rectal carcinoma (cT3-4 or cN+) treated with neo-CRT followed by total mesorectal excision. Treatment outcomes were compared according to clinical and pathological stage. Overall survival (OS), disease free survival (DFS) among patients with different clinical stage and pathological stage after neo-CRT. RESULTS The median follow-up time was 47 months (range, 14-98 months). Clinical T stage was associated with 5 year OS (p = 0.042) and 5 year DFS (p = 0.014) while clinical N stage was not associated with 5 year OS (p = 0.440), 5 year DFS (p = 0.711). Pathological T stage was associate with 5 year OS (p = 0.001) and 5 year DFS (p = 0.046); and N stage was associated with 5 year OS (p = 0.001), 5 year DFS (p = 0.002). The pathological stage was further classified into three groups: ypT0-2N0 in 91 patients (43.3 %), ypT3-4N0 in 69 patients (32.9 %) and ypT0-4N+ in 50 patients (23.8 %). While pathological stage (ypT0-2 vs ypT3-4N0 vs ypT0-4N+) was associated with 5 year OS (87.9 %, 75.5 %, 56.7 %, p = 0.000), 5 year DFS (74.5 %, 77.4 %, 50.5 %, p = 0.003). Multivariate analysis showed that ypN stage was an independent prognostic factor for patients 5 year DFS. CONCLUSIONS Pathological stage is strongly associated with treatment outcomes in patients with locally advanced rectal carcinoma treated with neo-CRT followed by total mesorectal excision, which may be used as guidance for further individualized treatment.