Gastric cancer cells adhere to the omental milky spot areas at different time points. (A-B) Image of milky spot macrophages (green) and large numbers of DiI-MFCs (red) concentrated in milky spot areas 12 h after intraperitoneal injection. (C-D) After 72 h, the number of DiI-MFCs decreased in milky spot areas while proliferating tumour cells in the milky spots and the formation of micrometastases were observed. Sporadic tumour cells were found in the omental non-milky spot areas. (E-F) Two weeks after the intraperitoneal injection, the milky spot areas were completely occupied by the proliferating gastric cancer cells and the cell cluster-type metastasis was observed. Proliferating cancer cell clusters were not observed in the non-milky spot areas and cancer cells formed single cell-type metastases. (magnification, ×200).