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.

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.

Can we improve the detection rate and interobserver agreement in capsule endoscopy?

BACKGROUND: Data about strategies for improving the diagnostic ability of capsule endoscopy readers are lacking. AIM: (1) To evaluate the detection rate and the interobserver agreement among readers with different experience; (2) to verify the impact of a specific training (hands-on training plus expert tutorial) on these parameters. METHODS: 17 readers reviewed 12 videos twice; between the two readings they underwent the training. The identified small bowel findings were described by a simplified version of Structured Terminology and classifies as clinically significant/non-significant. Findings identified by the readers were compared with those identified by three experts (Reference Standard). RESULTS: The Reference Standard identified 26 clinically significant findings. The mean detection rate of overall readers for significant findings was low (about 50%) and did not change after the training (46.2% and 46.4%, respectively). There was no difference in the detection rate among readers with different experience. The interobserver agreement with the Reference Standard in describing significant findings was moderate (k = 0.44; CI95%: 0.39-0.50) and did not change after the training (k = 0.44; CI95%: 0.38-0.49) or stratifying readers according to their experience. CONCLUSIONS: Both the interobserver agreement and the detection rate of significant findings are low, regardless of the readers' experience. Our training did not significantly increase the performance of readers with different experience.

Small bowel capsule endoscopy in clinical practice: a multicenter 7-year survey.

BACKGROUND AND AIM: Data about small bowel capsule endoscopy (SBCE) come from studies involving small and highly selected populations. The study aim was to describe extent of use, indications, results, complications, and practical issues of SBCE in clinical practice in a Northern Italian Region (Lombardia). MATERIALS AND METHODS: Twenty-three out of 29 invited centers fulfilled a specific questionnaire. RESULTS: Between 2001 and 2008, 2921 procedures were performed and both the number of centers performing SBCE (from 5 to 29) and the number of SBCE (from 7.2 to 69.2 per month) increased steadily. The main indications for SBCE were: obscure gastrointestinal bleeding (OGIB) (43.4%), unexplained anemia (23.9%), suspected Crohn's disease (7.8%) and abdominal pain (5.3%). Overall, SBCE was positive in 50% of cases, negative in 36% and undefined in 14%. The highest diagnostic yields were observed in patients with OGIB (62.5%), polypoid syndromes (74.1%), known (54.8%) or suspected (47.3%) inflammatory bowel disease, while the yields were low in patients examined for chronic diarrhea (27.4%) and abdominal pain (14.9%), 61 patients (2.1%) experienced capsule retention. Thirty-two of them eventually excreted the capsule naturally while endoscopic or surgical retrieval was necessary in 29 (1%) (in two because of obstruction). CONCLUSION: Over a period of 7 years the use of SBCE in Lombardia increased steadily confirming, in clinical practice, a high diagnostic yield and an acceptable safety profile.