Background and study aims: After noncurative endoscopic submucosal dissection (ESD) for differentiated-type
early gastric cancer (EGC), close observation is often preferred when a cancer-positive
lateral margin is the only noncurative factor. However, sometimes recurrence is found
during the observation period. This study aimed to examine risk factors for recurrent
cancer based on the long-term clinical outcomes after noncurative ESD in which the
only noncurative factor was a cancer-positive lateral margin.
Patients and methods: Among 3784 EGCs (3316 patients) treated by ESD between 1997 and 2010, 77 noncurative
differentiated-type EGCs (75 patients) were retrospectively analyzed after meeting
the following inclusion criteria: 1) the only noncurative factor was a cancer-positive
lateral margin; 2) close observation was selected after the ESD; and 3) > 1 year follow-up
after ESD.
Results: Locally recurrent cancer was found in 10 lesions within a median follow-up period
of 59.8 months; no metastasis or gastric cancer-related death occurred. The cumulative
incidence of local recurrence 5 years after ESD was 11.9 %. All locally recurrent
cancers were mucosal differentiated-type adenocarcinomas. Multivariate analysis indicated
that a cancer-positive lateral margin length of ≥ 6 mm was significantly associated
with local recurrence (hazard ratio 20.8; 95 % confidence interval 5.2 % – 82.9 %;
P < 0.001). The cut-off value of 6 mm was determined by the receiver operating characteristic
curve; the sensitivity and specificity for 5-year risk of developing local recurrence
were 66.7 % and 95.6 %, respectively.
Conclusions: A cancer-positive lateral margin length of ≥ 6 mm was an independent risk factor
for local recurrence, and this may be a useful criterion for selecting high-risk cases
for stricter management.
