Phagocytosis (cannibalism) of apoptotic neutrophils by tumor cells in gastric micropapillary carcinomas

Figure 1 Invasive micropapillary carcinoma characterized by cell clusters surrounded by lacunar spaces and fibrous stroma (A) and several micropapillae infiltrated by numerous neutrophils. A: HE staining, magnification × 100; B: HE staining, magnification × 400.

Figure 2 Micropapillary clusters were characteristically MUC-1 immunoreactive on the stroma-facing surface (“inside-out” pattern). Magnification × 200.

Figure 3 Intraepithelial neutrophils showing TUNEL-positivity. Magnification × 200.

Figure 4 Neutrophils showing cytoplasmic immunoreactivity for caspase-3 are found within cytoplasmic vacuoles of tumor cells (arrow). Magnification × 200.