This image shows a neuroblastoma tumor clump (blue arrow) in the same field as several mesothelial cells (red arrows).
While the individual cells are the same overall size, the tumor cells have larger nuclei and a smaller amount of cytoplasm than the mesothelial cells. The chromatin is finer in these tumor cell nuclei. Also, note the differences in the mesothelial cell chromatin pattern, which is much more coarse in texture with darker nucleoli present. The mesothelial cells have a distinct demarcation between adjacent cells, while this line of demarcation is not as apparent in the sheet of tumor cells.