title: Long-term outcomes of locally or radically resected T1 colorectal cancer.
abstract: OBJECTIVE
  Little is known about the long-term outcome of T1 colorectal cancer (CRC) following curative resection. The present study addressed the long-term outcome of locally or radically resected T1 CRCs.
  
  
  METHODS
  A total of 430 patients with T1 CRC who underwent local or radical resection were considered. Unfavourable histological factors were defined as positive resection margin, deep submucosal invasion, vascular invasion, Grade 3 and budding. The patients were classified as low-risk (unfavourable histological factor negative, n = 65) or high-risk (unfavourable histological factor positive, n = 365).
  
  
  RESULTS
  Over a median follow-up of 78.4 months, disease recurred in 16 (3.7%) patients in the high-risk group, and no recurrence in the low-risk group. Resection type and vascular invasion were significantly associated with recurrence. In the vascular invasion (+) high-risk group, both 5-year disease-free survival rate and 5-year overall survival rate were significantly associated with resection type (radical 94.6%, local 43.8%, P < 0.001, and radical 99.1%, local 66.7%, P < 0.001). In the vascular invasion (-) high-risk group, 5-year disease-free survival rate was also significantly associated with resection type (radical 98.9%, local 84.7%, P = 0.001). However, 5-year overall survival rate was not associated with resection type (radical 98.9%, local 95.2%, P = 0.816).
  
  
  CONCLUSIONS
  Local resection may be effective and oncologically safe in low-risk T1 CRC. Although additional surgery should be recommended for the locally resected high-risk T1 CRC cases, intensive surveillance without additional surgery and timely salvage operation may offer another treatment option, if vascular invasion is negative.
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: M J
authors.initials: MJ
authors.lastname: Nam
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.|Center for Cancer Prevention and Early Detection, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: K S
authors.initials: KS
authors.lastname: Han
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.|Center for Cancer Prevention and Early Detection, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: B C
authors.initials: BC
authors.lastname: Kim
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.|Center for Cancer Prevention and Early Detection, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: C W
authors.initials: CW
authors.lastname: Hong
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.|Center for Cancer Prevention and Early Detection, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: D K
authors.initials: DK
authors.lastname: Sohn
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: S Y
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: J Y
authors.initials: JY
authors.lastname: Baek
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: S C
authors.initials: SC
authors.lastname: Park
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Oh
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003082:Colectomy; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies
keywords: Colorectal neoplasm; recurrence; survival; treatment outcome