title: Factors Associated With the Performance of Extended Colonic Resection vs. Segmental Resection in Early-Onset Colorectal Cancer: A Population-Based Study.
abstract: OBJECTIVE
  Early-onset colorectal cancer (CRC) incidence rates are rising. This group is susceptible to heritable conditions (i.e., Lynch syndrome (LS)) and inflammatory bowel disease (IBD) with high metachronous CRC rates after segmental resection. Hence, extended colonic resection (ECR) is often performed and considered generally in young patients. As there are no population-based studies analyzing resection extent in early-onset CRC, we used CDC Comparative Effectiveness Research (CER) data to assess state-wide operative practices.
  
  
  METHODS
  Using CER and Louisiana Tumor Registry data, all CRC patients aged ≤50 years, diagnosed in Louisiana in 2011, who underwent surgery in 2011-2012 were retrospectively analyzed. Prevalence of, and the factors associated with operation type (ECR including subtotal/total/proctocolectomy vs. segmental resection) were evaluated.
  
  
  RESULTS
  Of 2,427 CRC patients, 274 were aged ≤50 years. In all, 234 underwent surgery at 53 unique facilities and 6.8% underwent ECR. Statistically significant ECR-associated factors included age ≤45 years, polyposis, synchronous/metachronous LS-associated cancers, and IBD. Abnormal microsatellite instability (MSI) was not ECR-associated. ECR was not performed in sporadic CRC.
  
  
  CONCLUSIONS
  ECR is performed in the setting of clinically obvious associated high-risk features (polyposis, IBD, synchronous/metachronous cancers) but not in isolated/sporadic CRC. However, attention must be paid to patients with seemingly lower risk characteristics (isolated CRC, no polyposis), as LS can still be present. In addition, the presumed sporadic group requires further study as metachronous CRC risk in early-onset sporadic CRC has not been well-defined, and some may harbor undefined/undiagnosed hereditary conditions. Abnormal MSI (LS risk) is not associated with ECR; abnormal MSI results often return postoperatively after segmental resection has already occurred, which is a contributing factor.
authors.affiliation: Department of Medicine, Division of Gastroenterology, Tulane University School of Medicine, New Orleans, Louisiana, USA.
authors.forename: Jordan J
authors.initials: JJ
authors.lastname: Karlitz
authors.affiliation: Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA.
authors.forename: Meredith R
authors.initials: MR
authors.lastname: Sherrill
authors.affiliation: Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA.
authors.forename: Daniel V
authors.initials: DV
authors.lastname: DiGiacomo
authors.affiliation: Epidemiology Program, Louisiana Tumor Registry, LSU Health Sciences Center School of Public Health, New Orleans, Louisiana, USA.
authors.forename: Mei-Chin
authors.initials: MC
authors.lastname: Hsieh
authors.affiliation: Epidemiology Program, Louisiana Tumor Registry, LSU Health Sciences Center School of Public Health, New Orleans, Louisiana, USA.
authors.forename: Beth
authors.initials: B
authors.lastname: Schmidt
authors.affiliation: Epidemiology Program, Louisiana Tumor Registry, LSU Health Sciences Center School of Public Health, New Orleans, Louisiana, USA.
authors.forename: Xiao-Cheng
authors.initials: XC
authors.lastname: Wu
authors.affiliation: Epidemiology Program, Louisiana Tumor Registry, LSU Health Sciences Center School of Public Health, New Orleans, Louisiana, USA.
authors.forename: Vivien W
authors.initials: VW
authors.lastname: Chen