CANCER PAIN
MANAGEMENT
Cancer pain management
Pain control should encompass “total pain”
Pain management specialists should not work in isolation
Education is fundamental to good pain management
Education in cancer pain management
A survey of physicians actively involved in cancer
care
1/3 wait until prognosis <6 months before giving
maximal analgesia (Von Roenn et al. 1993)
A study of 81 doctors only 5% could convert a
parenteral dose of morphine to an equivalent of
MST they were unfamiliar with palliative use of
radiation (Mortimer and Bartlett 1997).
Cancer pain has increased worldwide
an ageing population
WHO - 4 million people in the world have cancer pain
Site of primary tumour important
Pain not usually significant in early disease
1/3 with metastatic disease have significant pain
Most patients with end stage disease have pain
>50% patients report <70% pain relief with analgesics
Breakthrough pain
Transitory exacerbation of severe pain
on a background of otherwise stable chronic pain
in a patient on regular opioids
Incidence about 63%
Median number 4 severe breakthroughs per day
Median duration 30 minutes
Incident pain is breakthrough pain related to movement
(Portenoy & Hagen, 1990)
Basic pain management principles
Decrease pain and improve quality of life
Do no further harm
Allow patient and carers choices
Use resources as effectively as possible
Disease modification
Surgery
Radiation
Chemotherapy
Biological therapy
Basic pain management
Oral opioid analgesics
Adjuvant analgesics
WHO principles
Neuropathic pain
Individual variation
Opioid switching
Clinical bottom line
Paracetamol remains 1st line
Topical NSAIDs do work (NNT = 3) - no GI
NSAID
COXIBs
Ibuprofen (<2400 mg/day) probably
GI protection for those at risk
offer advantages in terms of GI s
short prognosis
Adjuvant analgesics
Tricyclic antidepressants NNT = 3.0
30% patients >50% pain relief
30% minor adverse reactions
4% have to stop treatment
SSRIs less effective (50% reduction side
No difference in efficacy across differen
Adjuvant analgesics – anticonvulsants
NNT = 2.6 in trigeminal neuralgia
Evidence of efficacy in diabetic neur
Evidence of efficacy in migraine prop
Relatively high risk for minor advers
Difficult cancer pain may need specialist pain
management
The WHO guidelines fail in 10-15% patients
This may be due to: opioid resistance
intolerable drug side effects
inability to deliver drugs effectively
e.g. GI problems
Alternatives
local anaesthetic/steroid somatic/sympathetic nerve blocks
neurolytic blocks
spinal ITDD
neuro-destructive surgical procedures
Combined approach aimed at several different levels within
the nervous system provides optimum relief with least
adverse effects
Simple nerve blocks
Complex
Nerve
Blocks
Autonomic Nerve
Blocks
Spinal drug delivery
Much smaller drug doses are needed
2% patients with cancer pain
When simpler and more economic methods have failed
Indications failure of systemic treatment
intolerable drug side effects
Epidural or intrathecal
drug delivery
External & internal systems
Choice of patient for spinal drugs
Contraindications
Local or systemic infection
Non-correctable co-aggulopathy
Patient refusal
Indications
Segmental pain or spasticity
Not head pain
? Neuropathic pain,
? Visceral pain, incident and cutaneous pain
Investigations
Cord compression ?
Good CSF flow
Life expectancy
External or internal systems
Life expectancy > 3 months ?
Intrathecal or epidural drug delivery?
Intrathecal drugs need not pass dura
Used in lower doses (10-20% epidural dose).
Large volume epidurally - spinal cord compression
Change in epidural fat influences drug delivery.
Epidural catheters blocked by fibrosis
Intrathecal or epidural drug delivery?
Complications within 20 days after implant
Intrathecal 25%
Epidural 8%
CSF leak was the main intrathecal complication
Complications after 20 days after implant
Intrathecal 5%
Epidural 55%
Epidurals frequently obstruct or dislodge
Implantable or external system?
•Pain problem
•Patient’s condition
•Experience of the team
Spinal drugs – infection
Infection rates vary
1 per 168 - 1 per 2446 catheter days
20% cultures from cassettes, syringes and filters
colonised without clinical
Infection associated with prolonged
catheter placement time > 100 min
Medtronic system
Spinal drug delivery
Pain may change as patient approaches
the end of life
Small pump reservoir may mean
alternative method of analgesia needed
Clinical bottom line
Pain relief better with intrathecal than epidural systems
Treatment failures more common with external epidural cathet
compared with internal IT catheters
Treatment failures less common with internalised IT catheters
than with internalised epidural catheters
Higher rates of system removal with internalised epidural
catheters than with internalised IT catheters
Higher rates of catheter complications with epidural
than with IT catheters
Spinal drugs
Opioids
Clonidine
Ketamine
Octreotide
Midazolam
Neostigmine
Baclofen
Local anaesthetics
Ziconatide
Spinal drugs – adverse effects
Dose escalation - Spinal opioid rotation
Sedation or itching with opioids
Hypotension with clonidine
Motor block with local anaesthetics
Subtle personality change
with ketamine
Hormonal and immune
suppression with opioids
Conclusions
A multi-disciplinary approach
Lessons now being applied to
Non-cancer pain
>25,000 patients have been
treated world-wide