75endoscopic evaluation within 6–12 months of surgery and subsequent initiation of
weight-based AZA in presence of endoscopic recurrence [ 59 ]. There was a nonsig-
nificant, marginal benefit of routine postoperative medical prophylaxis in prevent-
ing both endoscopic (17/32 vs. 18/31; RR 0.91; 95% CI 0.59–1.42) and clinical
(12/32 vs. 14/31; RR 0.83; 95% CI 0.46–1.50) recurrence compared to endoscopy-
guided therapy, respectively. The American Gastroenterological Association clini-
cal guidelines estimated that routine postoperative prophylaxis in a low-risk
population (0–1 risk factor for recurrence) estimated that per 1000 patients treated
with this strategy, there would be 34 fewer patients with clinical recurrence and 27
fewer patients with endoscopic recurrence [ 62 ]. In a high-risk patient population
(>1 recurrence risk factor), routine medical prophylaxis may result in 85 fewer
patients with clinical recurrence and 72 fewer episodes of endoscopic recurrence
per 1000 patients treated. It should be noted the AGA guidelines judged this trial to
be of low overall quality due to high risk of bias, significant difference in baseline
prognostic factors such as smoking rates, high attrition rate (33%), and early trial
termination due to slow recruitment (63/200 proposed patients). Consequently,
there is currently little high-quality evidence to suggest routine postoperative medi-
cal prophylaxis compared to a watch-and-wait strategy.
The choice between the two approaches should be one based on practitioner
comfort as well as shared decision-making with the patient with a balance of the
risk of disease recurrence on an individual level, risk of medication side effects, as
well as cost and convenience of medical and/or endoscopic therapy.
Future Research
Given the residual rates of recurrence even with aggressive postoperative medical
management, clearly there still exists an opportunity for improvement in prevention
and treatment of postoperative CD recurrence. Newer biologic agents such as the
anti-interleukin-12/anti-interleukin-23 agent ustekinumab and anti-integrin agent
vedolizumab may also prevent POR, but there are no data at the time of this publi-
cation, and future study is required. With an increasing understanding of the com-
plex mechanistic pathways underlying Crohn’s disease, potential mechanistic
signatures may be on the horizon to inform clinicians of the optimal medical regi-
men for prevention of POR. Similarly, distinct molecular markers of disease recur-
rence with increased sensitivity and specificity may help in detection of POR. A
validated risk score to predict risk of disease recurrence for an individual patient
based on presurgical factors would help patients and providers choose the appropri-
ate therapeutic approach postoperatively. New endoscopic scoring mechanisms are
being explored to determine key endoscopic findings predictive of response and
clinical outcomes. With the influx of biosimilar medications, data thus far in the
routine treatment of CD points toward nearly equivalent efficacy with biosimilars;
however, their efficacy in POR needs to be established. Similarly, the routine use of
combination of anti-TNF agents with thiopurines in prevention of POR has not
5 Use of Biologics in the Postoperative Management of Crohn’s Disease