Survival in Elderly Patients with Ulcerative Colitis and Colorectal Cancer

Abstract

Patients with ulcerative colitis (UC) have an increased riskof developing colorectal cancer (CRC). A meta-analysis byEaden et al. [1] that included 116 studies determined anoverall prevalence of CRC in any UC patients of 3.7% andcumulative probabilities of CRC of 2% by 10 years, 8% by20 years, and 18% by 30 years of UC duration. It alsoobserved a geographic variability in CRC incidence ratesfrom 5/1,000 person-years duration in the US, 4/1,000person-years duration in UK and 2/1,000 person-yearsduration in Scandinavia and other countries [1]. Severalother factors have also been suggested to influence the riskof CRC in patients with UC. A population-based cohortstudy by Anders Ekbom and his group from Swedenobserved an increased risk of CRC in association withmore anatomically extensive UC [2]. Patients withpancolitis (SIR 14.8, 95% CI 11.4–18.9) and left-sidedcolitis (SIR 2.8, 95% CI 1.6–4.4) had a 15-fold andthreefold increase in standardized incidence ratio, respec-tively, whereas those with UC limited to the rectum hadlower risk of CRC (SIR 1.7, 95% CI 0.8–3.2) [2]. Anotherreport from a combined Swedish and English populationcohort observed a significantly increased 19.2 excess riskof CRC in those with pancolitis (p = 0.001) and 3.6(p = 0.01) in those with left-sided colitis [3]. Younger ageat the onset of UC was also found to significantly impactthe risk of CRC based on data from population-basedcohort [2]. Patients younger than 15 years at the time ofUC diagnosis had the highest risk of CRC (SIR 118.3, 95%CI 63.0–202.3) [2]. An absolute risk of CRC was 40% inpatients younger than 15 years of age at the time of initialUC diagnosis, 25% for those aged 15–39 years, and 15%for those aged more than 40 years [2]. Multivariablelogistic regression identified that among analyzed vari-ables, age at the time of UC diagnosis, extent of UC atdiagnosis, and duration of follow-up only age younger than15 years (adjusted SIR 4.03, 95% CI 2.07–7.85) andpresence of pancolitis (adjusted SIR 5.27, 95% CI3.22–8.61) at the time of initial UC diagnosis were sig-nificantly associated with four–fivefold increased risk ofCRC [2]. The risk of CRC adjusted for extent of disease atthe time of initial diagnosis decreased with each increase inage group at diagnosis (age \15, 15–29, 30–39, 40–49,50–59, and 60 years and above) [2]. An analysis of thecohort from an academic referral center determined thatseverity of histologic inflammation within the colon of UCpatients increases the risk of CRC threefold (HR 3.0, 95%CI 1.4–6.3) [4]. Data from tertiary referral center case–control study found that increasing severity of both endo-scopically visible and histological colonic inflammation areassociated with 2.5-fold (OR 2.5, 95% CI 1.45–4.44) andfivefold (5.13, 95% CI 2.36–11.14) increased risk of CRCamong UC patients when compared to non-CRC UC con-trols, respectively [5].Another important risk factor for CRC observed inpopulation-based studies in patients with UC was a familyhistory of CRC in a first-degree relative. Patients with UCand family history of CRC were found to have twofoldincreased risk of CRC than those with negative familyhistory of CRC (RR 2.0, 95% CI 1.0–4.1) [6]. On the otherhand, family history of IBD was not associated with an