[Pathological diagnosis and treatment of malignant polyps]

Pathological diagnosis of colorectal malignant polyps is a core component guiding clinical treatment and subsequent management. Precise diagnosis and risk stratification of malignant polyps by pathologists serve as the fundamental basis for clinicians to formulate individualized treatment plans (including endoscopic resection or additional surgical resection). Accordingly, this article systematically elaborates on the key diagnostic points for malignant polyps, including the Paris endoscopic classification of colorectal polyps and its clinical significance, the histological definition of malignant polyps, assessment systems for submucosal invasion depth (such as Haggitt grading and Kikuchi SM grading), as well as the interpretation of critical high-risk histological features including poor differentiation, lymphovascular invasion, and tumor budding. In addition, diagnostic and differential diagnostic points for special lesion types, such as poorly differentiated intramucosal carcinoma and composite adenoma with microcarcinoid, are also summarized. Collectively, this review aims to provide comprehensive references for pathologists and clinicians, thereby promoting standardized management of colorectal malignant polyps.