Invasive micropapillary carcinoma: A distinct type of adenocarcinomas in the gastrointestinal tract

Figure 1 Characterization of typical invasive micropapillary carcinoma structures. A: Invasive micropapillary carcinoma in the invasive edges of the tumor; B: Morphologically, clusters of small rounded neoplastic cells without fibrous-vascular core. Hematoxylin and eosin stain, × 40, × 400, respectively.

Figure 2 Immunohistochemical characteristics of invasive micropapillary carcinoma structures. Positive immunoreaction of lymphatic endothelial cell performed by D2-40 (A) and lack of reaction in invasive micropapillary carcinoma (IMPC) structures (B). Immunohistochemical expression of E-catherin in membrane of conventional adenocarcinoma (C) and in cytoplasm of IMPC (D). The cytoplasmic expression of Beta-catenin was observed more frequent in typical adenocarcinoma (F) compare to IMPC (E). Magnification × 400.

Figure 3 Immunohistochemical characteristics of invasive micropapillary carcinoma of colon. Positive reaction of CK20 (A) and CEA (B). Magnification × 400.