Serrated polyps: innocent or guilty?

Serrated lesions represent a group of lesions with different genetic and biological features causing important clinical repercussions. Three types of serrated lesions are identified: hyperplastic, sessile adenomas (with and without dysplasia) and traditional serrated adenomas. Such lesions are now recognized as precancerous lesions.The carcinogenic process of serrated lesions follows a pathway including: alterations concerning activation of mitogen and protein kinase regulating the extracellular signal of other intracellular kinases (MAPK-ERK), inhibition of the apoptosis and hypermethylation of DNA and instability of microsatellites. Like for adenomatous polyps, the risk factors for serrated lesions are environmental factors, related to lifestyle and diet. The cancerogenic risk is increased by excessive alcohol consumption, obesity and poor intake of folate. When a high number of colorectal polyps with architecture serrated is diagnosed, it could be considered as serrated polyposis syndrome (SPS). According the most recent ESGE guidelines, the diagnostic criteria of the SPS, are: at least 5 polyps resected proximal to the sigmoid colon, 2 of which> 10 mm, or >20 serrated lesions of any size distributed in the entire colon. This condition presents a high risk for personal and/or familiar CRC, for this reason a regular screening colonoscopy should be performed in these patients and in their first-degree relatives.

Serrated polyps: innocent or guilty? / Pólipos serrados: ¿inocente o culpable?

ABSTRACT Serrated lesions represent a group of lesions with different genetic and biological features causing important clinical repercussions. Three types of serrated lesions are identified: hyperplastic, sessile adenomas (with and without dysplasia) and traditional serrated adenomas. Such lesions are now recognized as precancerous lesions.The carcinogenic process of serrated lesions follows a pathway including: alterations concerning activation of mitogen and protein kinase regulating the extracellular signal of other intracellular kinases (MAPK-ERK), inhibition of the apoptosis and hypermethylation of DNA and instability of microsatellites. Like for adenomatous polyps, the risk factors for serrated lesions are environmental factors, related to lifestyle and diet. The cancerogenic risk is increased by excessive alcohol consumption, obesity and poor intake of folate. When a high number of colorectal polyps with architecture serrated is diagnosed, it could be considered as serrated polyposis syndrome (SPS). According the most recent ESGE guidelines, the diagnostic criteria of the SPS, are: at least 5 polyps resected proximal to the sigmoid colon, 2 of which> 10 mm, or >20 serrated lesions of any size distributed in the entire colon. This condition presents a high risk for personal and/or familiar CRC, for this reason a regular screening colonoscopy should be performed in these patients and in their first-degree relatives.

RESUMEN Las lesiones serradas representan un grupo de lesiones con diferentes características genéticas y biológicas que provocan importantes repercusiones clínicas. Se identifican tres tipos de lesiones serradas: adenomas hiperplásicos, sésiles (con y sin displasia) y adenomas serrados tradicionales. Estas lesiones se reconocen actualmente como lesiones precancerosas.El proceso carcinogénico de las lesiones serradas sigue una vía que incluye: alteraciones relativas a la activación del mitógeno y de la proteína quinasa reguladora de la señal extracelular de otras quinasas intracelulares (MAPK-ERK), inhibición de la apoptosis e hipermetilación del ADN e inestabilidad microsatelital. Al igual que en el caso de los pólipos adenomatosos, los factores de riesgo de las lesiones serradas son factores ambientales, relacionados con el estilo de vida y la dieta. El riesgo cancerígeno aumenta con el consumo excesivo de alcohol, la obesidad y la ingesta deficiente de folatos. Cuando se diagnostica un número elevado de pólipos colorrectales con arquitectura serrada, puede considerarse como síndrome de poliposis serrada (SPS). Según las guías más recientes de la ESGE, los criterios diagnósticos del SPS, son: al menos 5 pólipos resecados proximalmente al colon sigmoides, 2 de los cuales> 10 mm, o > 20 lesiones serradas de cualquier tamaño distribuidas en todo el colon. Esta condición presenta un alto riesgo de CCR personal y/o familiar, por lo que debe realizarse una colonoscopia de cribado periódica en estos pacientes y en sus familiares de primer grado.