From the Guidelines
Yes, a diminutive sessile serrated lesion can still harbor dysplasia, and its presence significantly increases the malignant potential of the lesion. According to the most recent and highest quality study by the US Multi-Society Task Force on Colorectal Cancer 1, the risk of dysplasia in sessile serrated lesions (SSLs) is a key factor in determining the recommended follow-up interval after colonoscopy and polypectomy. The study provides a risk-stratified approach to repeat colonoscopy intervals, with SSLs with dysplasia being considered high-risk lesions that warrant a shorter surveillance interval of 3 years.
Key Points
- Diminutive SSLs, typically defined as those less than 10 mm in size, can harbor dysplasia, although this is relatively uncommon 1.
- The presence of dysplasia in an SSL significantly increases its malignant potential, as it indicates that the lesion has progressed beyond the early molecular alterations that characterize non-dysplastic SSLs.
- Complete endoscopic resection is recommended for all SSLs regardless of size, with careful histological examination to assess for dysplasia 1.
- The finding of dysplasia in a diminutive SSL should prompt consideration of a shorter surveillance interval due to the increased risk of synchronous or metachronous advanced neoplasia 1.
Recommendations
- All SSLs, regardless of size, should be completely resected and undergo careful histological examination to assess for dysplasia.
- Patients with SSLs that harbor dysplasia should be offered a shorter surveillance interval, typically 3 years, due to the increased risk of advanced neoplasia 1.
From the Research
Sessile Serrated Lesions with Dysplasia
- A diminutive sessile serrated lesion can still harbour dysplasia, as evidenced by studies that have identified dysplastic components within these lesions 2, 3, 4, 5.
- The presence of dysplasia in sessile serrated lesions is a significant concern, as it can progress to colorectal cancer through the serrated neoplasia pathway 3, 4, 5.
- Research has shown that sessile serrated lesions with dysplasia can exhibit distinct molecular and biological characteristics, including mutations in genes such as BRAF, APC, and TP53 2.
- The diagnosis of sessile serrated lesions with dysplasia can be challenging due to their flat shape and relatively short window of detection, making it essential to develop effective diagnostic tools and strategies 3, 4, 6.
- Studies have identified clinical and endoscopic predictors of cytological dysplasia or cancer in sessile serrated adenomas/polyps, including increasing age, lesion size, and the presence of an adenomatous pit pattern 4.
- Immunohistochemical analysis has also been used to study sessile serrated adenomas with low- and high-grade dysplasia and early carcinomas, providing insights into the molecular mechanisms underlying these lesions 5.