Researchers have reached a better understanding of why tumors that have invaded bones or the nervous system generate so much pain, and they have tailored treatments to each process. Physicians have improved their ability to measure levels of painkilling medications in body fluids and to correlate these levels with patients' reported sense of relief. They have also devised drug-delivery protocols designed to stop pain before it starts. All these advances serve to maximize relief while minimizing drug side effects, such as grogginess, constipation and nausea. For example, those who have undergone surgery with a high likelihood of eliminating the disease may regard their acute but transitory pain as more bearable than do patients with chronic pain from more advanced disease.
Depression can also exacerbate perception of pain.
Prescribing antidepressants can thus alleviate both psychological and physical discomfort. Clinicians have found innovative ways to help patients describe accurately the ebb and flow of both physical pain and psychological distress. For example, very young children and others who have trouble communicating verbally can indicate their level of distress by pointing to one in a series of cartoon faces whose expressions range from no pain to agonizing pain. Although some types of pain resist treatment, studies indicate that as many as 95 percent of cancer patients can get relief if properly medicated. Tragically, many continue to suffer needlessly.