Pain in cancer may arise due to many reasons and is often the presenting complaint leading to the diagnosis of cancer. It may be
- Related to cancer itself or its spread to other body parts
- A late presentation due to side effect of treatments such as chemotherapy, radiotherapy, and surgery
- A result of extra stress placed on other body parts for example shoulder pain due to using of a stick for walking
- A totally unrelated coincidental problem such as arthritis
Pain can be differentiated into background pain (which is always present in the background and is managed with regular medications) and breakthrough pain (pain which breaks through your regular pain relief). Breakthrough pain may occur unprovoked or may be triggered by external or internal factors. In cancer patients, different types of pain may coexist. It is not just limited to pain arising from inflammation and tissue damage for example cancer of pancreas spreading to neighboring organs and nerves leading to visceral and neuropathic pain respectively and a distant spread to bones producing bone pain. Different types of pain present differently for example
- Neuropathic/ Nerve pain is generally described as burning, shooting, electric shock-like or stabbing pain with associated tingling or numbness. It may be a consequence of cancer itself or a result of treatments such as chemotherapy (chemotherapy-induced peripheral neuropathy- CIPN).
- Visceral Pain originates from viscera (organs in the body cavity) and is generally described as deep aching, squeezing and cramping sensation
- Bone pain presents as an aching, throbbing sensation. Some cancers have a preference to spread to bones
Pain relief needs to be tailored to the cause, severity, and duration of pain. In most cases, reasonable control can be achieved by using a combination of methods. Multimodal, Multidisciplinary approach provides the opportunity to maximize pain relief and provide support not only for the physical needs but also for the emotional, spiritual and social needs.
Some of the management options available via a pain clinic are
This involves using different classes of medications to optimize pain control. Using a combination of drugs helps to minimize side effects and maximize the benefits. Whilst considering the drug therapy many factors need to be considered like the type of pain, cause and severity of pain, other medical problems and medications being used, medications tried previously, pre-existing nausea/vomiting, constipation, ability to take and absorb medications, liver and kidney function, etc. Apart from the standard medications mentioned in other sections some other medications are used more often in cancer pain such as steroids, bisphosphonates (for bone pain).
Nerve blocks, Radiofrequency & Neurolytic procedures
Nerves are commonly targeted in pain-relieving interventions, for example, pudendal nerve for perineal or rectal pain, suprascapular nerve for shoulder pain, intercostal nerves for chest wall pain, etc. The pain impulses being transmitted via the nerves can be temporarily blocked using local anesthetics. The transmission of impulses can be reduced for longer duration using Neurolytic procedures, which involve the injection of alcohol or phenol instead of local anesthetic. Examples of neurolytic procedures include
- Coeliac plexus, splanchnic nerves neurolysis
- Hypogastric plexus neurolysis
- Lumbar sympathetic neurolysis
Radiofrequency procedures e.g.
suprascapular nerve pulsed radiofrequency for shoulder pain involves exposure to high-frequency electrical current in the RF range (≈ 500 kHz). This exposure can be continuously generating high temperatures or pulsed where the temperature is kept below 42 °C. Pulsed RF can be used to target most nerves including those with motor components. The resulting neural modification effect’s the transmission of pain impulses producing pain relief.
Spinal procedures e.g. epidural, intrathecal pumps
Certain procedures such as pumps to deliver medicines directly in the spine (intrathecal pumps) are performed more often for cancer pain.
Cancer is often accompanied by anxiety, depression, and fear of the worst. A psychologist can help in analyzing these thoughts rationally and developing a positive approach. They can help by teaching relaxation techniques, coping strategies and by reducing the effect of mood on pain.
Complementary and alternative therapies including Acupuncture, TENS, meditation, Ayurveda and wellness. For more information on how these can be helpful please follow the respective links
Dr. Amod Manocha is a Senior Consultant and Head of Pain Management Services at Max Multispecialty Hospital, Saket. He is trained as a Pain Management Specialist and an Anaesthetist in the UK. He has over 13 years of work experience in the UK including working as a Chronic Pain Consultant in many UK hospitals.