title: Surveillance for asymptomatic recurrence in resected stage III colon cancer: does it result in a more favorable outcome?
abstract: BACKGROUND
  Evidence from dated and moderate quality trials supports a modest survival benefit for intensive surveillance in resected colon cancer (CC). This study evaluates surveillance in a modern population-based cohort of stage III CC patients (pts).
  
  
  METHODS
  Records of pts who initiated oxaliplatin-based adjuvant chemotherapy (AC) for stage III CC between 2006-2011 at the British Columbia Cancer Agency (BCCA) were reviewed. Kaplan-Meier and log rank test were generated to investigate whether diagnosis of recurrence based on symptoms was associated with worse overall survival (OS). OS1 and OS2 were measured from date of recurrence or date of initial surgery, respectively.
  
  
  RESULTS
  Of 635 pts who received AC for stage III CC, 175 pts (27.5%) recurred and 118 (18.6%) died at a median follow-up of 67.7 months. Recurrences were detected by surveillance in 149 pts (41% by CEA elevation and 44% by abnormal imaging), and symptoms in 26 pts (15%). Patients with surveillance-detected recurrences had a shorter median relapse-free survival (RFS) (18.5 vs. 25.3 months, HR 1.82, P<0.001), and longer median OS1 (28.5 vs. 6.5 months, HR 0.37, P<0.001). However, median OS2 was not significantly different (50.9 vs. 39.1 months, HR 0.66, P=0.091). Pts with surveillance-detected recurrence received more potentially curative metastasectomy (39% vs. 7%, P=0.002) and chemotherapy (70% vs. 50%, P=0.03).
  
  
  CONCLUSIONS
  In this modern population-based cohort study, the OS impact of detecting asymptomatic recurrences in stage III CC is unclear. However, pts with asymptomatic recurrences were more likely to receive potentially curative metastasectomy and chemotherapy.
authors.affiliation: Department of Medical Oncology, British Columbia Cancer Agency, Vancouver, BC V5Z 4E6, Canada.
authors.forename: Martin
authors.initials: M
authors.lastname: Smoragiewicz
authors.affiliation: Department of Medical Oncology, British Columbia Cancer Agency, Vancouver, BC V5Z 4E6, Canada.
authors.forename: Howard
authors.initials: H
authors.lastname: Lim
authors.affiliation: Department of Medical Oncology, British Columbia Cancer Agency, Vancouver, BC V5Z 4E6, Canada.
authors.forename: Renata D'Alpino
authors.initials: RD
authors.lastname: Peixoto
keywords: Colon cancer (CC); carcinoembryonic antigen/blood; humans; neoplasm recurrence local/diagnosis; survival rate; tomography X-ray computed