Aims:
Recurrence rate in colorectal polyps with indeterminate or positive lateral margin
on histology is unclear. We evaluated the long-term outcomes of patients with indeterminate
or positive lateral margin after endoscopic resection and related factors with recurrence
in large, sessile or flat polyps.
Methods:
We collected the data for 156 lesions with large size (≥1 cm), sessile or flat shape,
indeterminate or positive lateral margin in histology and more than 24 months of follow-up
intervals between Jan 2009 and Sep 2017. We analyzed recurrence rate, time to recurrence,
histology at recurrence and risk factors related with recurrence.
Results:
During follow-up periods (24 – 86 months, mean 44.2), recurrence rate was 7.1% (11/156)
and mean time to recurrence was 39.2 months (20 – 59). Recurrence rate of cuff-off
techniques were 3.2% (4/127) in en bloc, 9.1% (1/11) 2 piecemeal resection and 33.3%
(6/18) in ≥3 piecemeal resection. In analysis for risk factors related with recurrence,
only ≥3 piecemeal resection were significantly related with recurrence in both univariate
analysis and multivariate analysis (OR 16.92, p = 0.037).
Conclusions:
Following patients with indeterminate or positive lateral margin after endoscopic
resection in large, sessile or flat colorectal polyp, recurrence rate was relatively
low and time to recurrence was long than 12 months. Therefore, surveillance interval
for these patients can be extended for more than 12 months. However, short-term follow-up
is mandatory in case of ≥3 piecemeal resections or suspected submucosal cancer in
morphology because of risk of recurrence or interval cancer.
