Evaluation of the effectiveness of morphological, demographic, endoscopic and molecular the distinction of serrated lesions of the colon and rectum

• Grant number: 16/08200-7
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2016
• End date: August 31, 2018
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal Investigator: Renata de Almeida Coudry
• Grantee: Renata de Almeida Coudry
• Host Institution: Hospital Sírio-Libanês. São Paulo , SP, Brazil
• City of the host institution: São Paulo

Abstract

Colorectal cancer (CRC) is one of the most common malignancies in industrialized countries and major cause of cancer death in the world. Recently a new pathway has been shown to be important in the evolution of CRC, the call via serrated. This pathway is characterized by the presence of hypermethylation of CpG sequences in the promoter region of certain genes, called methylator phenotype (CIMP). In most studies observed a relationship between the presence of CIMP tumors and certain clinical and pathological features, including, age, smoking, most affected women, located on the right side of the colon, microsatellite instability (MSI), mutation of BRAF gene and absence of mutation in the TP53 gene, the latter being extremely common aspect in the adenoma-carcinoma pathway. Moreover, unlike the adenoma-carcinoma sequence, where the adenoma is the precursor lesion, the serrated pathway, the precursor lesion has knurled aspect and until recently was interpreted as hyperplastic polyp with no possibility of transformation. Considering the recent involvement of serrated lesions in the development of colorectal cancer becomes imperative reliable identification of the types of injuries. Furthermore, the possibility of the use of a molecular diagnosis can help differentiate serrated lesions and decipher its progression. This study aims at an evaluation of reproducibility among gastrointestinal pathologists in the diagnosis of serrated lesions using the established morphological criteria and molecular characterization of these polyps. (AU)