Predictive value of rectal bleeding for distal colonic neoplastic lesions in a screened population R. Ferraris a , C. Senore b, *, M. Fracchia a , S. Sciallero c , L. Bonelli d , W.S. Atkin e , N. Segnan b , and the SCORE Working Group, Italy 1 a Unit of Gastroenterology, Mauriziano ‘‘Umberto I’’ Hospital, Turin, Italy b Unit of Epidemiology, CPO Piemonte, ASO S Giovanni Battista, Via S Francesco da Paola 31, 10123 Turin, Italy c Unit of Gastroenterology & Nutrition, Natl Institute for Cancer Research, Genoa, Italy d Unit of Clinical Epidemology and Trials, Natl Institute for Cancer Research, Genoa, Italy e Imperial Cancer Research Fund, Colorectal Cancer Unit, Harrow, Middlesex, UK Received 3 February 2003; received in revised form 30 May 2003; accepted 5 August 2003 Abstract The aim of this study was to determine the diagnostic value of rectal bleeding for distal colorectal cancer (CRC), or large (510 mm) adenomas among an average-risk population. A cross-sectional survey was conducted among individuals aged 55–64 years, who attended sigmoidoscopy (FS) screening in the context of a multicentre randomised trial of FS screening for CRC. Sensitivity, specificity and positive predictive value (PPV) of rectal bleeding for large distal adenomas or CRC were calculated. Rectal bleeding was reported by 8.8% of 8507 patients examined (15% of those with large adenomas and 29% of those with CRC). The risk of CRC was increased when bleeding was associated with an altered bowel habit: odds ratio (OR)=10.42; 95% Confidence Interval (CI): 4.08–26.59; the corresponding OR for isolated bleeding was 5.29 (95% CI: 2.28–12.30). Rectal bleeding carries an increased risk of distal neoplastic lesions. However, most lesions are detected among asymptomatic subjects. This finding suggests that screening represents the optimal strategy to detect CRC or large adenomas in the distal colon in the targeted age range. # 2003 Elsevier Ltd. All rights reserved. Keywords: Colorectal neoplasm; Rectal bleeding; Predictive value; Screening 1. Introduction Rectal bleeding is usually considered to be a suspi- cious symptom for colorectal cancer (CRC) [1–3]. However, it is a fairly common symptom in the general population, with a reported prevalence of approxi- mately 15% [4,5]. In studies conducted among hospital patients undergoing investigation for lower abdominal symptoms, the reported prevalence of polyps or CRC varied between 19 and 35% [6–10]. Lower prevalence figures have been reported among primary care patients seeking care for rectal bleeding [4,11–14]. Since only a few (approximately 15–20%) of patients with rectal bleeding seek medical advice [4,5,15], these figures may represent an overestimate of the predictive value of the symptom in the population. The positive predictive value (PPV) of rectal bleeding for distal polyps or CRC was 8% in a small prospective study of a randomly selected group of healthy men, who had not consulted their physician for this symptom and underwent sig- moidoscopy (FS) to at least 30 cm [16]. We assessed the predictive value of rectal bleeding in identifying distal neoplastic lesions among average-risk individuals, aged 55–64 years, enrolled in a multicentre trial of efficacy of FS screening for CRC [17]. As all screenees had FS independent of their symptoms, we could obtain an unbiased estimate of the predictive value of bleeding among people attending screening. We also assessed the predictive value of other symptoms, such as abdominal pain and altered bowel habit, which are also considered to be symptoms of colorectal cancer 0959-8049/$ - see front matter # 2003 Elsevier Ltd. All rights reserved. doi:10.1016/j.ejca.2003.08.002 European Journal of Cancer 40 (2004) 245–252 www.ejconline.com * Corresponding author. Tel.: +39-011-566-5355; fax: +39-011- 633-3861. E-mail address: carlo.senore@cpo.it (C. Senore). 1 The SCORE trial investigators are given in the Appendix.