Cancer Pain: It can be controlled

The America Cancer Society estimates there will be approximately 1,334,000 new cancers diagnosed this year in the United States. Of those patients, approximately 1/3 receiving treatment will suffer from moderate to severe pain. With more advanced disease, the percentage experiencing significant pain dramatically increases. The majority is due to direct tumor involvement with bone being the prominent site. The scope of this problem is huge, but there are highly successful methods for dealing with cancer pain, which often requires several treatment modalities. These can include drug therapy, anticancer treatment with radiation therapy, chemotherapy and surgery, nerve blocks, neurosurgical intervention and behavioral approaches.

Pain Defined | Back to Top

The International Association for the study of Pain has defined pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Three types of pain are described, somatic, visceral and neuropathic. Somatic pain is characterized by dull, aching discomfort that is well localized while visceral pain, caused by involvement of organs like the stomach, pancreas and bowel, is poorly localized and is often more of a deep, pressure-like pain. Neuropathic pain is caused by injury to nerves and can be described as burning in nature.

The doctor’s assessment of a patient’s pain is critical. It should include questioning about severity, duration, location and alleviating / aggravating factors. The description of the pain is also important to help differentiate its type (somatic, visceral vs. neuropathic). All this information is important to help the physician decide appropriate treatment.

Best Method | Back to Top

One of the best ways to improve cancer pain is to treat the cancer itself. Radiotherapy is very effective in alleviating pain caused by cancerous involvement of bone and soft tissue. The therapy can be delivered as external treatments using powerful x-ray machines called linear accelerators. Patients with widespread bone involvement can also receive a single radioactive isotope injection (e.g., Metastron, Quadramet) with often good relief. Chemotherapy can also be utilized to control pain by treating widespread disease. Bisphosphonates (e.g., Aredia, Zometa) are a class of drugs that help bones strengthen and actually slow the progression of bone metastases. Surgery has been used to remove painful tumors and in the case of metastatic prostate cancer, orchiectomy (removal of the testicles) can result in immediate pain relief from bone metastases.

Drug Therapy | Back to Top

Although treatment of the cancer itself can bring pain relief, it can take time to work and be incomplete. Drug therapy using pain medications can afford quick and effective pain control. Opioids are used extensively of which morphine is the prototype. The World Health Organization has developed a three step analgesic (pain relief) ladder to assist heath care providers in effectively managing pain. It begins with treatment of mild pain and progresses to the treatment of more severe pain. For mild discomfort non-opioid drugs (e.g., aspirin, Tylenol, etc.) are recommended perhaps in conjunction with an antidepressant (e.g., amitriptyline) or antiepileptic (e.g., Neurontin). Moderate pain often calls for a weak opioid (e.g., codeine, hydocodone) alone or with an adjuvant medication like aspirin or Tylenol. Severe pain requires a more potent opioid (e.g., morphine, oxycodone, fentanyl) again either alone or in conjunction with an adjuvant.

Two Important Concepts | Back to Top

Two very important concepts to remember is that for adjuvant drugs like aspirin, Tylenol, Celebrex, etcetera, there is a “ceiling effect”. There is a point where raising the dose higher does not improve its pain control ability but does significantly increase the chance of an adverse side effect. In contrast, opioids have no ceiling and the dose can be increased until the pain is controlled. Underdosing of opioids is a common problem and in cancer patients who may have chronic, severe pain, the dose should be systematically increased to “whatever it takes to relieve the pain”.

Side Effects| Back to Top

Side effects of opioid use include sedation and constipation. The sedation or sleepiness usually occurs on initial use and when the dose is increased. However, it is temporary and often lessens with continued use. The constipation can be a significant problem and patients should be placed on stool softeners and mild laxatives from the start.

Common Concerns | Back to Top

Common concerns with the use of pain medications like morphine is that a patient will become “addicted” or that by using such a powerful medicine their condition must be terminal. It is extremely rare for a cancer patient to develop a psychological or physical “craving” as they are taking it for a specific reason, to control pain. Uses of potent pain medication in no way implies a “lost cause” and is needed to alleviate discomfort, temporary or chronic, in many cancer patients.

Pain is one of the more significant problems that can be associated with cancer and its treatment. Yet with proper assessment and treatment it can be successfully controlled in the vast majority of patients. It just takes close and honest communication between patients and physicians.