Expression of Cytokeratin 20 Indicates Invasive Histological Phenotype in Poorly Differentiated Colorectal Adenocarcinoma

摘要

Background/Aim: Cytokeratin (CK) 20 expression is an independent prognostic factor of poorly differentiated adenocarcinoma (PDA) of the colon and rectum. We aimed to investigate the mechanism of its involvement through a clinicopathological study. Patients and Methods: We analyzed 156 surgically resected PDAs, which were sub-classified as solid type (Porl) showing expansive growth, or non-solid type (Por2) showing infiltrative growth. Associations of CK20 expression with morphological features and molecular markers were analyzed. Results: CK20~+ PDA (n=91) was associated with more advanced disease stage and unfavorable prognosis compared with CK20~ PDA (n=65). Pathologically, CK20~+ PDA was significantly associated with p53 overexpression, Por2, abundant fibrous stroma, and stepwise de-differentiation, while CK20~ PDA was significantly associated with mismatch repair deficiency, Porl, sparse fibrous stroma, and de novo histo gene sis. Conclusion: CK20 expression in PDA is closely associated with invasive histological features, providing prognostic significance, and may also point to a specific histogenetic pathway.