Traditional serrated adenoma

Traditional Serrated Adenoma

Micrograph of a traditional serrated adenoma.

A traditional serrated adenoma (TSA) is a type of colorectal polyp that is characterized by its serrated or saw-tooth appearance under the microscope. TSAs are considered precursors to colorectal cancer, particularly when they exhibit dysplastic features.

Histology

Traditional serrated adenomas are distinguished by their unique histological features. They typically display a serrated architecture with elongated crypts and a complex glandular pattern. The epithelial cells often have eosinophilic cytoplasm and may show nuclear atypia. Unlike other serrated lesions, such as hyperplastic polyps and sessile serrated lesions, TSAs have a more pronounced dysplastic component.

Pathogenesis

The pathogenesis of traditional serrated adenomas involves genetic and epigenetic alterations. Mutations in the BRAF gene are commonly associated with TSAs, similar to other serrated pathway lesions. These mutations lead to activation of the MAPK/ERK pathway, promoting cellular proliferation and survival. Additionally, TSAs may exhibit CpG island methylator phenotype (CIMP), which contributes to their progression to malignancy.

Clinical Significance

Traditional serrated adenomas are clinically significant due to their potential to progress to colorectal cancer. They are often found in the left colon and rectum, although they can occur throughout the colon. Surveillance and removal of TSAs during colonoscopy are important to prevent the development of cancer.

Diagnosis

The diagnosis of traditional serrated adenoma is primarily based on histological examination of biopsy or resection specimens. Pathologists look for the characteristic serrated architecture and cytological features to distinguish TSAs from other types of polyps. Immunohistochemical staining may be used to support the diagnosis and assess for molecular markers.

Treatment

The primary treatment for traditional serrated adenomas is endoscopic removal. Complete excision is recommended to prevent progression to cancer. Patients with TSAs may require more frequent surveillance colonoscopies to monitor for recurrence or the development of new lesions.

Related Pages

• Colorectal cancer
• Colorectal polyp
• Hyperplastic polyp
• Sessile serrated lesion

Traditional serrated adenoma

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