A cancer patient may experience pain due to the tumor or metastasis is harming or oppressing organs or structures of the body where they are located, such as nerves, muscles, blood vessels, bones, etc. Normally, cancer pain is classified into three types: somatic, visceral or nerviopatico, according to the structure or organ that is damaged. Somatic pain is pain experienced in the skin, muscles and bones;visceral occur in the viscera, such as intestines, pancreas, liver, etc;and neuropathic pain affects the nervous system. In the event that a cancer patient will experience back pain may be because the tumor is pressing some part of the structure thereof.