What+makes+cancer+such+a+difficult+disease+to+cure?**


 * cancer cells change and multiply too fast
 * there are many drugs and treatments that help slow down cancer, but no treatment can cure cancer.
 * because the cells multiply and divide so much, the treatments don't know what they're supposed to be treating anymore.
 * cancer cells don't die when they're told to
 * at a certain point in a cells life, they're supposed to die. however, cancer cells completely ignore the "death signals", and they keep on dividing.
 * cancer cells form tumors
 * unlike regular cells, cancer cells can pile up on top of each other to form tumors.
 * cancer can metastasize
 * it is easy to remove a cancerous tumor in the early stages. However, there is a chance that the cancer can metastasize even after the tumor has been removed. This makes curing cancer much harder because the cancer is stronger the second time around. Many patients don't survive after cancer has metastasized.