In Italy 250,000 subjects every year are affected by malignant tumors, causing 150,000 deaths/year. The global index (statistic prevalence) of oncological patients, either at first diagnosis, or restored to health or under treatment, aggregates 1 million and 500 thousand individuals. During his whole lifetime, every male can be exposed to the risk of tumor developing, up to 1/3 times against 1/5 of a female. At the same time it is true that just only in a decade, 5-year survival expectance for this kind of patients has significantly grown: in Italy, during the late '70s only 33% of them reached this survival, becoming 39% in the late '80s. This aim was achieved also through the recruitment of the sensibilization to the prevention and the early diagnosis, properly known as "screenings", which, from the original experiences regarding gynecology, (female breast and uterus), are involving more and more anatomic districts. The purpose of this brief is illustrating the procedures, either usually validated ones, or affirming ones, to identify colorectal neoplasms at early stady or precancerous intestinal lesions.