10-lakh new cancer patients are diagnosed every year in India and 60% of them are diagnosed in advanced stage, so they require only pain management and palliative care.
Though 60%-80% of them complain of inadequate pain relief by their physician but more than 90% cancer pain can be adequately controlled with different pain management procedures.
THE PAIN CAN ARISE FROM THE ANY OF THE FOLLOWING :
- Tumor invation or compression of other tissues by tumor
- Surgeries and biopsies
- Radiation damage to tissues
- Neuropathies caused by chemotherapy or other treatments
- Blocked or damaged organ structures (visceral pain)
- Decreased mobility and arthopathies (musculo-skeletal pain)
- Pathologic fracture
The types of pain are classified as nociceptive (somatic & visceral) and neuropathic. Nociceptive, somatic bone pain is the most common type of cancer pain. It can be caused by metastasis to bone or a post-surgical incision. Patient may describe the pain as aching, well-localised, sharp, gnawing or dull.
Visceral pain receptors are activated by infiltration, compression, extension or stretching of the organs in the abdomen, pelvis and thorax. Visceral pain (i.e. pancreatic cancer) is described as crampy, colicky, less well-localised, vague, aching, deep, dragging, squeezing and dull.
Neuropathic pain receptors are activated by nerve damage secondary to chemical injury, tumor compression or infiltration of a component of nervous system such as peripheral nerve or spinal cord. The type of pain may be described as burning, itching, numbness, tingling, squeezing. Most cancer patient have somatic and visceral pain and 15 - 20% have neuropathic pain.
From the above discussion it is seen that cancer pain is inevitable at some stage of the disease, but at the same time 90% of the cancer pain are curable by some means or other. What are the reasons then for inadequate cancer pain control? Why most of the cancer patients are suffering from cancer pain at some stage of the disease?
THE MOST IMPORTANT REASON IS LACK OF AWARENESS IN :
- Health care workers (including doctors)
- Policy makers
- Public (patients and their relatives)
- Lack of financial resources, lack of infrastructure
- Lack of adequately trained personnel who can perform Interventional pain management
- Fear among treating physician about drug dependency, and drug abuse
- Non-availability of opioids due to legal restriction
WHY THE CANCER PAIN MUST BE PROPERLY CONTROLLED?
APART FROM BEING EXCRUCIATING AND INTOLERABLE IN NATURE THERE ARE OTHER REASONS TO CONTROL THE CANCER PAIN.
- Cancer pain can be controlled
- Psychological effects of cancer pain can be avoided. (anxiety, depression, lack of sleep, anger, suicidal attempts)
- Precipitation of diseases like diabetes, hypertension can be avoided
- Meaningful and productive social life can be lived
- Effective pain control can prolong life
- Relatives also relieved from constant worries
WHAT ARE THE WAYS TO TREAT THE PAIN?
THE METHODS OF TREATMENT OF CANCER PAIN ARE MANY LIKE :
- Pharmacotherapy (treatment with oral or injectable pain killer medicines) with analgesics (opioid & non-opioid); co-analgesics (anti-depressant & anti- convulsant) and others
- Interventional pain management(IPM)
- 3 stage analgesic ladder (Pharmacotherapy)
- 1st stage- NSAIDs +/- NSAIDs
- 2nd stage-Weak opioid +/- NSAIDs
- 3rd stage-strong opioid +/- NSAIDs
- Interventional pain management (IPM) in 4th stage +/- NSAIDs
WHAT ARE THE INDICATIONS OF IPM IN CANCER PATIENTS?
- Severe pain is expected to persist
- Failure of analgesic drug treatment
- Non-availability of morphine
- Limited life expectancy
- Well localized pain
- Pain is not multi-focal in origin
- Pain is of visceral or somatic in origin
- Coexisting or preexisting problems curable with IPM
TYPES OF IPM IN CANCER PATIENTS
- Neurolytic procedures
- Advanced interventional pain management
WHAT IS NEUROLYSIS?
It is a procedure (a type of IPM) by which nerve fibres carrying pain sensation is irreversibly destroyed to obtain permanent pain relief.
METHODS OF NEUROLYSIS :
Neurolysis can be done by applying neurolytic agents like: phenol, alcohol, or by some other methods like: cryoneurolysis (neurolysis by applying cold), radiofrequency ablation (neurolysis by applying heat), neurectomy (neurolysis by operation).
NAME OF SOME IMPORTANT INTERVENTIONS :
- Splanchnic Nerve block (for upper abdominal cancer)
- Coeliac Plexus Block (for upper abdominal cancer)
- Superior Hypogastric Block (Lower abdminal cancer)
- Ganglion Impar Block (Pereneal pain from rectum)
- Intra-thecal drug delivery system