Editorial: Resecting Assumptions—Do Proctocolectomy Guidelines Hold Up? Author's Reply

We appreciate the editorial comment [1] from Drs Chaudhary and Axelrad, highlighting the key results of our study [2]. The principal findings were primarily the survival gap between patients with concomitant inflammatory bowel disease (IBD) and colon cancer compared to colon cancer patients without IBD; and, secondly, that only 10% of patients with IBD received a proctocolectomy. The strength of our study was the population-based design with high validity of inclusion of both colon cancer patients and patients with IBD. This allowed for robust survival estimates and descriptive statistics of current surgical management of colon cancer in Sweden. In our opinion, a different, more aggressive tumour biology is evident in patients with IBD-associated colon cancer. The characteristics of IBD generate mutant cells that rapidly spread along the colon, precipitating the development of colon cancer [3]. As a result, colon cancer in patients with IBD can be generated through a different mutational sequence. Therefore, early identification of IBD patients at highest colorectal cancer (CRC) risk is crucial. Promising results were recently published [4]. Those authors retrospectively measured the pattern and burden of somatic genomic copy number alterations in biopsies of low-grade dysplasia in IBD patients and found this to be an accurate predictor of CRC. Patients with primary sclerosing cholangitis (PSC) constitute another key group; one study found a nine-fold increased CRC risk in patients with PSC, compared to matched IBD patients [5]. In our study, more than one fifth of IBD patients with colon cancer younger than 50 years old had co-existent PSC. Reducing the inflammatory burden is an appealing approach to reduce CRC risk in IBD patients. However, IBD patients treated with advanced medical therapies have higher rates of incidental CRC and a subsequent unfavourable CRC prognosis than patients without advanced medical therapy [6]. Patients treated with advanced medical therapy, particularly those with refractory inflammation, perhaps mandate increased surveillance. Drs Chaudhary and Axelrad highlighted the seemingly low risk of metachronous CRC among IBD patients in our cohort. However, those patients at the highest risk of a second CRC had probably received a colectomy, introducing a selection bias in this estimate. Even though only 10% of IBD patients in our cohort received a proctocolectomy, we found greater adherence to guidelines in patients younger than 50, with almost 70% receiving a colectomy or proctocolectomy. This implies a discrepancy between clinical practice and international guidelines. We suggest future research to focus on identifying those IBD patients with the highest risk of CRC and suitable for a colectomy, preferably before the development of CRC, and on the optimal surgical management of CRC in IBD patients. Pending stronger evidence, we suggest that young IBD patients, and those with synchronous tumours, PSC or active inflammation should be considered for proctocolectomy after being diagnosed with CRC. The authors' declarations of personal and financial interests are unchanged from those in the original article [2]. Erik Lundqvist: conceptualization, writing – original draft. Pär Myrelid: conceptualization, writing – original draft. Caroline Nordenvall: conceptualization, writing – original draft. This article is linked to Lundqvist et al. et al. papers. To view these articles, visit https://doi.org/10.1111/apt.70296 and https://doi.org/10.1111/apt.70322. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.