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stapled anastomosis (0%, 0%, and 3%, respectively) compared to sutured end to end
(5%, 11%, and 24%, respectively, plog-rank = 0.007) [ 33 ]. These findings have been
corroborated in several other, mostly retrospective, studies [ 24 ]. However, in two
prospective randomized controlled trials of anastomosis type in 98 and 139 CD
patients, both studies failed to show a significant difference in either clinical or
endoscopic recurrence by anastomotic type.
Three studies have independently found myenteric plexitis to be a significant
predictor of POR, both endoscopic and clinical [ 34 , 35 ]. Furthermore, the severity
of plexitis appears to correlate with severity of endoscopic recurrence at both early
(3 months) and later (12 months) time points.
Characteristic findings in the surgical specimen have also been investigated as
potentially related to POR. The degree of histologic inflammatory activity has been
shown in several studies to correlate with increased rates of anastomotic recurrence
in ileocolonic CD [ 24 ]. The presence of granulomas in surgical pathology has con-
tradictory data with several large studies favoring a predisposition to POR if the
surgical specimen contained granulomas [ 36 – 38 ]. However, the significance of this
histologic finding in relation to POR remains uncertain.
Several early reports suggested an association between wide macroscopic mar-
gins and lower recurrence risk. Fazio et al. conducted a randomized controlled trial
of 152 CD patients who underwent ileocolonic resection to limited (2 cm) or
extended (12 cm) margin from macroscopic disease [ 39 ]. There were no significant
differences in recurrence rates between the groups (25% limited, 18% extended). Of
the group with microscopic activity at the margin, 31.7% had recurrence, whereas
17.8% of activity-free margin patients had POR though this difference failed to
reach significance (p = 0.07). Thus, margin size or histologic activity does not seem
to influence POR.
Prevention of Postoperative Recurrence
Given the frequency and impact of CD recurrence postoperatively, many studies
have aimed to determine potential ways to prevent or reduce POR. Historically,
treatment paradigms for POR followed a “bottom-up” approach with the use of
steroids, antibiotics, and/or 5-aminosalicylates (5-ASA). As disease flared or pro-
gressed, immunomodulators or biologics (if available at the time) were then added.
Thus there exists a time effect in studies of medical therapy for POR.
Nonbiologic Treatment Options
Traditional therapies including 5-ASAs, antibiotics, and immunomodulators have
been shown to moderately reduce the risk of clinical and endoscopic recurrence.
Mesalamine, a 5-ASA agent, is a safe but minimally effective option to reduce
B.H. Click and M. Regueiro