Surgery for Colorectal Cancer in Crohn’s Disease: Should We Perform a Total Proctocolectomy for All Patients With High-Grade Dysplasia and Cancer in Crohn’s Disease?
In the 2007 guidelines, the recommendation for colorectal cancer (CRC) associated with Crohn’s disease (CD) was resection (level of evidence III, grade of recommendation B). The appropriate extent of resection for dysplasia including high grade, multifocal, and dysplasia associated with lesion or mass was reported as “unclear…ranging from a limited segment…to the entire colon and rectum.3” However, the recent guidelines1 recommended that “total proctocolectomy (TPC) should be considered for patients with carcinoma, nonadenoma-like dysplasia associated with lesion or mass, high-grade dysplasia or multifocal low-grade dysplasia” (level of evidence I, grade of recommendation B).
This was primarily based on 2 studies, which indicated that 14% to 40% of patients undergoing segmental resection for CRC develop metachronous tumors.3,4 The study by Kiran et al3 recommended TPC for dysplasia, because 16 patients (44%) undergoing TPC or subtotal colectomy (STC) had multifocal dysplasia. The study by Maser et al4 reported on 64 patients who had segmental resection or STC for colon cancer. Nineteen (40%) of 47 who had segmental resection developed metachronous tumor. Six (35%) of 17 who had STC had metachronous cancer. The mean time to new cancer was reported as ≈7 years.
Should we perform a TPC on all patients with dysplasia or CRC in CD? We believe that there is still insufficient evidence in the literature to make a strong recommendation for TPC. The studies by Maser et al4 and Kiran et al3 were only small case series, such that the reported recommendation grade of IB is puzzling. TPC is associated with higher morbidity, short- and long-term complication profiles, and permanent stoma, because IPAA is not usually a recommended option in CD.
Recent studies have shown that the incidence of cancer in CD is much lower than once thought. Selinger et al5 reported an incidence of CRC in CD to be 1% at 10 years and 2% at 30 years. The meta-analysis by Laukoetter et al6 indicated that the risk of CRC was lower in CD than ulcerative colitis, and a meta-analysis by von Roon et al7 showed that the risk of rectal cancer in CD was not significantly higher than in the general population. There are limited data on the risk of metachronous and synchronous CRC in CD. With this in mind, the recommendation of total proctocolectomy based on 6 patients having metachronous cancer after STC and 19 after segmental resection,4 as well as a higher risk of multifocal dysplasia,3 may need additional consideration.