Answer :
cancer cells are a cluster of cells without any boundary and normal cells are just together but not clustered.
normal cells stop growing when enough cells are present.
cancerous cells continues to grow none stop until it becomes a tumor.
cancer cells dont interact with other cells like normal cells do.
normal cells are either repaired or will die when they are damaged or they get old, cancer cells are either not repaired or do nut undergo apoptosis.
i hope this helps :)