Dealing with Pain in Advanced Cancer
Patients with advanced cancer and their families frequently worry about having unrelenting pain. Many fear that cancer pain will become unbearable, especially during the last days of life. It may therefore surprise many that a significant number of terminal cancer patients do not have a significant pain issue. Moreover, with the advances in pain treatments, the vast majority of cancer patients can be assured of adequate pain relief – indeed, no cancer patient need to die in pain when they receive appropriate pain treatment.
Understanding Cancer Pain
Pain is a complex phenomenon that is usually expressed as an unpleasant bodily experience. While pain is often a result of direct physical injury caused by the cancer, the experience of pain may also be caused or worsened by disturbances in emotional, social, psychological and spiritual well-being. In this article, we will deal with the physical aspects of cancer pain; the other aspects shall be covered in other articles.
How does Cancer Cause Pain?
Cancer can cause pain by damaging the normal tissues around it as it grows. Pain may also result from the cancer mass exerting pressure on organs and vital structures, from cancer obstruction of the intestinal or urinary tracts. It can also damage nerves, which may lead to peculiar pain syndromes as well as the loss of function and numbness over the affected areas. When cancer spreads in bones, cancer can cause pain from bone fractures. Some cancers can also cause pain through metabolic disturbances. It is important to find out how the cancer causes the pain as there are specific ways of managing the different causes of pain.
How is Cancer Pain Treated?
Cancer pain may be relieved by treating the cancer directly using surgery (by removing tumour), medications (e.g. chemotherapy, targeted therapy, immunotherapy) and radiation (radiotherapy).
Even when these options are not available, painful symptoms may also be successfully treated using analgesic (“pain-killers”), steroids (such as dexamethasone, prednisolone) , anti-inflammatory drugs (NSAIDs such as Ponstan, Naproxen, Synflex, Arcoxia) , and neuropathic pain medications (medications that reduce nerve pain, such as Lyrica and Gabapentin). When pain is caused by cancer causing bone fractures, fixing the fracture surgically may be useful in selected situations. There may also be ways to inject analgesic or anaesthetic medications to numb the nerves that are transmitting the painful signals. Emotional support and counselling is also integral and other non-medical treatments (massage, acupuncture) can be discussed with your doctor.
As many cancer patients experience pain from more than one mechanism or cause, a combination of approaches may be required to provide lasting pain relief with minimal side effects.
Use of Opioids
Among the various strategies for pain relief, opioids (morphine and its related medications, such as oxycodone and fentanyl) are well established medications for dealing with moderate to severe cancer pain. When used properly for pain relief, opioids are generally safe and effective. The most common side effect is constipation, which may be addressed with the regular use of bowel laxatives (such as lactulose, senna, ducolax, fleet enema) . Other side effects such as nausea and drowsiness tend to be transient and occur at the start of opioid treatment in patients who have not been previously exposed to opioids and those whose dose has been too quickly increased. Despite its effectiveness and safety, many patients and their families try to avoid the use of opioids. Often, this may be traced to prevalent myths about opioids.
Table 1. Common Myths about Opioids (Morphine and Related Medications)
1. All cancer pains can only be managed by morphine
As explained earlier, there are many other modalities of treatment for cancer pain. While there are many other medications that can help, when used appropriately, morphine is a very useful and safe general-purpose medication for various types of cancer pain.
2. Morphine and other strong opioids work by making the person drowsy and unaware of their pain
Opioids are primarily used for their ability to relieve pain. They may cause some sedation, especially at the initial stages of using, but when they are used appropriately, sedation can be minimised.
3. Morphine and other strong opioids should be reserved for pain at the end-of-life
Many people are worried that when they use morphine early, they may “run out” of pain medicines later. Some may also fear the use of morphine because they believe its use imply that they will die soon. As a result, when they finally accept the use of opioids, they are also likely to be close to death. This is unfortunate as many people can still remain comfortable and can do many of the things that they enjoy when they do not have pain, before they become very ill.
4. Morphine and other strong opioids will hasten death and should not be given unless the patient is dying.
Opioids are frequently used for people who are not dying from a terminal disease, for example, during surgery. When used appropriately, opioids are safe and will not lead to hastening of death. Indeed, there is some evidence that with adequate pain control, some patients may actually live longer.
5. Morphine and other strong opioids should be avoided because it will lead to addiction.
There is ample evidence to show that opioids, when used solely for the relief of pain, will not lead to addiction. When patients required higher doses of opioids, it is more likely to be due to increased levels of pain as the disease progresses. This is not accompanied by the psychological and behavioural changes that characterise addiction.
Getting Help for Cancer Pain
At OncoCare Cancer Centre, we believe that it is vital that all patients receive adequate pain relief for cancer pain. Having advanced cancer is a challenging enough experience. There is no need to endure the unnecessary suffering of pain, which can be alleviated by the means described earlier. Seek help to deal with pain from an oncologist or a palliative medicine physician. In this way, one can hope to be comfortable even in the setting of advanced cancer.
Dr Tan Yew Seng
FAMS (Palliative Medicine)
Dr Tan Sing Huang
FAMS (Medical Oncology)