Long-Term Outcomes In Patients With YpTO Rectal Cancer After Neoadjuvant Chemoradiotherapy And Curative Resection

Aim For locally advanced rectal cancer(LARC)patients treated with neoadjuvant chemoradiotherapy(NCRT),significant pathological response of primary tumor has been proposed to identify candidates for organ preservation.However,it does not address metastatic lymph nodes in the mesorectum.The aim of this study was to assess the incidence of lymph node metastases in ypTO patients treated with NCRT and curative resection and to explore risk factors associated with survival.Method This was a retrospective study of patients with ypTO rectal cancer after NCRT and curative resection at a tertiary care center in China from 2005 to 2014.Results 323 patients underwent surgery after NCRT,and ypTO was achieved in 60(18.6%)patients and one patient was excluded due to lack of follow-up.Of these 59 patients,lymph node metastases was found in the mesorectum(ypT0N+)in 8(13.6%)patients.After a median follow-up of 52 months,5-year recurrence-free survival(RFS)(82.7%vs.62.5%,p = 0.014)and overall survival(OS)(90.9%vs.70.0%,p = 0.032)were excellent in ypNO than ypN+ patients.Multivariate analyses showed that ypN+status(p = 0.009)and perioperative blood transfusion(p = 0.001)were significantly independent risk factors associated with recurrence,however,no factor was correlated with 5-year OS.Conclusion Patients with ypTONO rectal cancer can achieve excellent long-term outcomes,however,positive lymph nodes or tumor deposits can still be found in 13.6%of ypTO patients.Nodal positivity in the mesorectum and perioperative blood transfusion are independent risk factors for recurrence.