Identifying high risk factors in locally advanced rectal cancer patients with ypT0-2N0 after preoperative chemoradiation

Objective: The objective of this study was to identify high risk factors for survival in locally advanced rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiation. Methods: In this study, Surveillance, Epidemiology, and End Results Program (SEER)-registered rectal cancer patients, and patients from Fudan University Shanghai Cancer Center (FUSCC) after preoperative chemoradiation were combined to identify poor prognostic patients with ypT0-2N0. Results: 2375 patients from SEER data and 106 patients from FUSCC were analyzed. The SEER data showed that less than 12 lymph nodes and mucinous/signet ring cancer were the two risk factors. The 5-year cancer specific survival (CSS) in patients with none, one or two risk factors was 91.5%, 88.5% and 70.3%, respectively (P < 0.001). Our cancer center data showed that less than 12 lymph nodes and mucinous/signet ring cancer were also the two risk factors. The 3-year disease free survival (DFS) in patients with none, one or two risk factors was 96.2%, 85% and 37.5%, respectively (P = 0.013). Conclusions: Two risk factors were identified in this study that correlated independently with a worse survival in patients with ypT0-2N0. The current results indicated that adjuvant chemotherapy may be not spared in these patients who have 1 or 2 risk factors.