Background Entosis is a process which occurs between two epithelial cells after losing their connection to the basement membrane. It starts with activating Rho kinase pathway in one cell. Then, this cell forms adherens junction with another detached cell and actively invades into it to create cell-in-cell structure. The inner cell preserves its morphology and maintains proper mitochondrial potential while being inside another cell. As a result of entosis the inner cell may undergo lysosomal degradation, divide or leave the outer cell and then function normally. Two last options prove that the inner cell’s condition is quite good. Entosis was observed in breast epithelial cells. Cannibalism is a process in which one tumor cell engulfs another cell – tumor cell, lymphocyte, erythrocyte, neutrophile etc. It ends in lysosomal degradation of engulfed cell. These phenomenon was described in different human tumors. Our team has observed different cell-in-cell structures among BxPC3 pancreatic cancer cells. We asked whether these structures are the result of entosis or cannibalism. Methods BxPC3 pancreatic cancer cell line was used in all experiments. Electron and confocal microscopes were used to observe different cell-in-cell structures. Cells for confocal microscope were stained with CFDA-SE, Hoechst and Phalloidin. Cells for electron microscope were fixed with glutaraldehyde and than analysed by using Transmition Electron Microscopy. To evaluate the influence of Rho kinase inhibitor on the number of cell-in-cell structures we incubated cells with this compound for 24 hours. After that time twenty randomly chosen images were taken in confocal microscope in each field to assess the number of cell-in-cell structures in each case. Results We observed the following cell-in-cell structures in confocal microscope: a cell inside a cell, two cells inside a cell, a cell inside a cell inside another cell and mitosis inside a cell. We found adherens junctions between inner and outer cell in electron microscope. Rho kinase inhibitor decreases the number of cell-in-cell structures in a dose dependent manner. Conclusion Mitosis inside a cell is a structure which shows that inner cell is in good condition and does not present any sign of damage. Rho kinase pathway and adherens junctions are involved in creating cell-in-cell structures among BxPC3 pancreatic cancer cells. To conclude, we observed entosis in BxPC3 pancreatic cancer cell line.