Is there a role for sigmoidoscopy in symptomatic patients? Analysis of a study correlating distal and proximal colonic neoplasias detected by colonoscopy in a symptomatic population

Abstract

-Background -Colonoscopy is the gold standard exam to investigate patients with colonic complaints. However, its availability is limited in developing countries. Sigmoidoscopy has been advocated as a first procedure in colorectal cancer screening strategies, in order to select those who need colonoscopy. Aim -To study the correlation between distal and proximal colonic neoplasias in symptomatic patients 50 years or older and patients 40 to 49 years old who underwent colonoscopy at a gastrointestinal endoscopy unit in 1999 and 2000 with the purpose to evaluate its role in a symptomatic population. Methods -All colonoscopies performed in our Department in 1999-2000 were reviewed. The distal colon was defined as the colonic segment aboral to the splenic flexure. Advanced neoplasias were defined as adenomas larger than 10 millimeters and adenocarcinomas. Results -Of the 2,701 colonoscopies retrieved, 1,125 were enrolled in this study. Prevalence rates for adenoma, advanced adenoma and carcinoma were 28.9%, 4.6% and 4% in the group of 830 patients 50 years or older (mean age 65 years, 491 women). The finding of one small (<10 mm) adenoma in the distal bowel doubled the likelihood of finding a proximal neoplasia (OR = 2.12, 95% CI, 1.27-3.54), and multiple (OR = 3.99, 95% CI, 1.72-9.28) or advanced (OR = 3.73, 95% CI, 1.81-7.7) adenomas increased this risk even further. Of the patients without adenoma or carcinoma in the distal colon, 1.93% had proximal advanced neoplasia. In the group of 40 to 49-year-old patients (n = 395; mean age 44.8 years, 208 women) the prevalence of adenomas (14.9%), advanced adenomas (3.4%), and carcinomas (1.7%) was lower. Conclusions -The likelihood of finding a proximal lesion is greater in patients with distal neoplasias. This likelihood is further increased when adenomas are multiple or larger than 10 mm. One out of 52 patients 50 years or older with an apparently normal distal colon has advanced proximal neoplasia. Sigmoidoscopy is not an adequate exam for symptomatic patients aged 50 years or older. HEADINGS -Colonoscopy. Sigmoidoscopy. Proctoscopy. Colonic polyps. Colorectal neoplasms. Adenoma.

Diagnostic Yield of Flexible Sigmoidoscopy in Symptomatic Population: An Insight to Rapid Access Sigmoidoscopy Clinic

“…As seen in many studies, there is a preponderance of the disease in the male population. 18 We identified that passing mucus per rectum and episodic faecal incontinence are unique presenting symptoms for distal colonic polyp which has not been described in previous reports. However, the relatively small number of polyps detected and the overall small patient pool may have resulted in a Type I error or false positives in other words Therefore large studies looking specifically at symptoms related to distal polyps will be required to further validate these findings.…”

The Relationship Between Distal and Proximal Colonic Neoplasia: A Meta-Analysis

“…It is widely established that men have a higher and earlier risk of colonic neoplasia than women 6,10,11,20,35,42–44,52,53,58,66–71. Age and gender are interacting factors, with women younger than 50 years having a lower risk of proximal than distal neoplasia, while males in the same age group have a higher prevalence of distal than proximal neoplasia,16,65,72 women between 50 and 70 years showing an increasing incidence of proximal neoplasia compared to women of younger age,62,65,69 and gender differences diminishing after the age of 70 62.…”

“…Formal guidelines generally do not consider HP to be markers of PN or PAN 3–5. Seven of nine colonoscopy studies published to date revealed no significant associations between HP and PN,6–14 and only one of eight colonoscopy studies reported a significant association between HP and PAN 6,10,15–20. Pathology studies, however, suggest that HP could develop into cancer through microsatellite instability and hypermethylation pathways 21–25.…”

Desenvolvimento de neoplasias/adenomas avançados colorretais no seguimento a longo prazo de pacientes submetidos a colonoscopia com polipectomia

“…Nos últimos anos, estudos comparativos têm enfatizado e indicado a colonoscopia como o exame inicial para o rastreamento do câncer colorretal devido sua melhor custo-efetividade em relação às outras opções de rastreamento, especialmente se considerados os níveis de adesão vislumbrados na Trabalho realizado na Fundação Rio-grandense Universitária de Gastroenterologia (FUGAST) e no Curso de Pós-graduação em Ciências Médicas da Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA). 1 Santa Casa de Porto Alegre; 2 Departamento de Gastroenterologia da UFCSPA; 3 FUGAST, Porto Alegre, RS. Correspondência: Dr. Júlio Carlos Pereira-Lima -Rua Comendador Rheingantz, 910/801 -Bairro Bela Vista -90450-020 -Porto Alegre, RS.…”

“…Os adenomas colorretais -que se apresentam na forma de pólipos ou lesões planas -são as neoplasias mais frequentemente encontradas em colonoscopias de rastreamento, assim como em pacientes sintomáticos acima dos 50 anos (3,19) . Devido ao conhecimento da sequência adenoma-carcinoma e das evidências científicas de que esta é a via principal da carcinogênese colorretal, é possível diminuir a incidência e a mortalidade da doença através de programas de rastreamento populacional (5) .…”