Incidence of Metachronous Distant Metastasis and ypN Classification Influence Patient Survival in Endosonographically Confirmed uT3 Rectal Cancer after Neoadjuvant Therapy and R0 Resection: A Historical Cohort Analysis.

BACKGROUND Tumor response after neoadjuvant radiochemotherapy (NRC) prior to surgery and other parameters are likely to have an influence on the survival rate of patients suffering from T3 rectal cancer. METHODS 51 patients (17 female, 34 male; 59.0 years; Apache < 9 points: 95.1%; ASA I-II 88.3% and ASA III 11.8%) were treated with NRC (50.4 Gy; 5-fluorouracil/folinic acid) 4-6 weeks prior to surgery because of uT3 rectal cancer (G2: 96%; adenocarcinoma 86.3%; cUICC II 62.7%). NRC led to a tumor response (TR) (ypT0-ypT2) in 45.1% (ypT0N0M0 7.8%). RESULTS Neither the age of patients nor Apache/ASA score, histology, UICC staging, ypTNM, Dukes staging, infiltration of vessels, surgical procedure, local recurrence nor TR had a significant influence on the patients' survival time. Patients with metachronous distant metastasis (MDM) during the follow-up period (mean: 8.2 years; 1 month to 14.5 years) and patients with ypN1-ypN2 had a significantly shorter survival time. CONCLUSIONS NRC prior to surgery leads to a remarkable TR rate but has no significant impact of TR on the patients' survival time. Occurrence of MDM during the follow-up period and ypN1/N2 status do have a greater influence. It is necessary to investigate larger cohorts of patients in the future to obtain more conclusive results and to define factors with influence on survival.