577P - Perineural invasion as a prognostic factor in rectal cancer treated with preoperative chemoradiotherapy: A multicenter retrospective study

Date 08 October 2016
Event ESMO 2016 Congress
Session Poster Display
Topics Surgical Oncology
Colon and Rectal Cancer
Radiation Oncology
Presenter Ji Won Park
Citation Annals of Oncology (2016) 27 (6): 149-206. 10.1093/annonc/mdw370
Authors J.W. Park1, S. Ryoo2, B.K. Park3, S. Kang4, D. Kim4, J.H. Oh3, S. Jeong2, K.J. Park2
  • 1Department Of Surgery, Seoul National University Hospital, 03080 - Seoul/KR
  • 2Department Of Surgery, Seoul National University Hospital, Seoul/KR
  • 3Center For Colorectal Cancer, National Cancer Center, Goyang/KR
  • 4Department Of Surgery, Seoul National University Bundang Hospital, Seongnam-si/KR



Preoperative chemoradiotherapy is used as a standard treatment in locally advanced rectal cancer. Perineural invasion has been suggested as a poor prognostic factor in colorectal cancer. However, the prognostic role of perineural invasion for rectal cancer after preopreraitve chemoradiotherapy is not well studied in multicenter data.The aim of this study is to evaluate the prognostic impact of perineural invasion in rectal cancer treated with preopreraitve chemoradiotherapy.


From Jan 2002 to Dec 2010, 1260 patients, with locally advanced rectal cancer treated with preopreraitve chemoradiotherapy at three institutions, were included. The median radiation dose was 5040 cGy with concurrent chemotherapy. Their medical charts were retrospectively reviewed including pathology report. Survival analysis was performed to identify the clinicopatholgic factor affecting disease-free survival (DFS) and overall survival (OS).


Perineural invasion was positive in 221 patients (17.5%). The patients with perineural invasion were associated with more advanced pathologic stage, less tumor regression grade, more circumferential resection involvement, more positive lymphatic invasion, and more positive venous invasion. The DFS and OS of the perineural invasion positive patients was significantly poorer than that of the perineural invasion negative patients (5-year DFS = 46.5% vs 81.1%, p 


Perineural invasion were associated with poor DFS and OS in rectal cancer patients who undergo preoperative chemoradiotherapy. These patients require careful monitoring after surgery.

Clinical trial identification

Legal entity responsible for the study

Ji Won Park


Seoul National University Hospital


All authors have declared no conflicts of interest.