Aspects of colorectal cancer screening, methods, age and gender

Abstract

Colorectal cancer (CRC) is, besides breast, prostate, lung and skin cancers, the most common cancer worldwide and is suitable for screening. The incidence of CRC varies considerably in different parts of the world: in well-developed countries, the incidence is between 30 and 70 per 100 000 inhabitants, whereas in less-developed countries such as sub-Saharan Africa, it is 10-20/100 000 inhabitants. Women have a lower incidence of CRC, which is usually one-third of total incidence. Several studies have shown that it is possible to decrease mortality from CRC with about 20%, which is evidenced through the data from countries with screening programmes. Though the method of choice to identify blood samples in faecal matter is under debate, the most feasible way is to perform colonoscopy. Other methods include more advanced faecal analyses, testing for mutations from CRC, sigmoidoscopy, CT colonoscopy or optical colonoscopy. Colonoscopy is in most countries not available in sufficient amount and has to be carried out with great accuracy; otherwise, lesions will be missed to identify, thus leading to complications. Gender is an issue in CRC screening, as women have about 20% fewer colorectal adenomas and CRCs, but they also have more right-sided lesions, which are more difficult to detect with tests for faecal blood since they create less blood in faeces. Thus, other strategies may have to be developed for women in order for screening to have the same effect. It is essential to introduce colorectal cancer screening in all countries together with other clinical pieces of advice such as information on smoking, obesity and exercise in order to reduce one of the most dangerous cancers.

Evaluation of colonoscopic findings in patients undergoing colonoscopy due to positive fecal occult blood test: a single center experience

“…When the localizations of tumors and polyps were examined, more than 50% of the lesions were detected in the rectum and sigmoid colon. This finding of the current study was compatible with the literature (8,(14)(15). There are molecular differences between right-sided and leftsided colon tumors and sidedness of the colorectal cancers are important, especially in the metastatic behaviour and in response to anti-EGFR drugs.…”

Colorectal Cancer Screening: Have We Addressed Concerns and Needs of the Target Population?

“…It should be noted that a large amount of information provided in this review regards colonoscopy, the most commonly reported "preferred" test by the general population. The preponderance of this topic may be due to the large number of studies conducted in USA (42/83 of the studies included) where opportunistic colonoscopy screening is more common than in other countries (e.g., EU countries where many population-based CRC screening programs use FOBT) [156]. For this reason, in order to obtain a more complete understanding of population preferences concerning CRC screening tests, more studies should be conducted in a wider variety of settings.…”

Recent advances in targeted drug delivery systems for resistant colorectal cancer

“…Diet, gut microbiome, obesity, smoking, alcohol, chromosomal instability and CPG methylation pathway are factors that predisposed individuals to CRC. It is highly suggested to people who are under risk of CRC to undergo screening test such as fecal test, sigmoidoscopy, colonoscopy and CT colonoscopy per intervals [ 161 ].…”