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Epidemiology of Cancer and
Cancer Pain
Cancer is one of the most important causes of death all over
the world. e Global Cancer Statistics published in 2002
reported that there were 10.9 million new cases of cancer,
6.7 million cancer deaths and 24.6 million persons alive with
cancer [92]. ere has been a rising trend over the last decade
[93] and cancer deaths have been estimated to be 9 and 11.4
million by the year 2015 and 2030 respectively [153]. In
2002, lung cancer was rated the most common (1.35 million),
followed by breast cancer (1.15 million) and colorectal cancer
(1 million). As far as the number of living cancer patients
(prevalence) is concerned, breast cancer is the highest (4.4
million), followed by colorectal (2.83 million) and prostate
(1.88 million) cancers. is may be attributed to their earlier
detection and better prognosis than lung cancer [92].
Pain commonly occurs in patients suffering from cancer of
all stages. Bonica estimated that there were 16 million cancer
patients worldwide suffering from pain [7]. Overall, at least
50% of cancer patients suffer from pain. e percentage
increases to around 70–95% in advanced stages [7, 8, 103,
138]. In a study conducted in France, 57% of cancer patients
reported pain due to their disease. Of those with pain, 69%
rated their worst pain impaired their ability to function [69].
is has been confirmed in two studies in Taiwan and Ireland
[51, 61]. Cancer pain also commonly occurs in children. It has
been estimated that pain occurred in 48% of those paediatric
patients hospitalised and 27% in those seen as outpatient [87].
Another report showed that pain occurred in 57% of children
with cancer in Italy [25].
Cancer Pain
9
Siu Lun TSUI, Chi Wai CHEUNG
EPIDEMIOLOGY OF CANCER AND
CANCER PAIN
ADVERSE EFFECTS OF CANCER
PAIN
Patient suffering
Influence on hospital resources
and society
PATHOPHYSIOLOGICAL
MECHANISMS OF CANCER PAIN
Pain mechanism at the molecular
level
Pain due to direct effects of
malignant tumour and
metastases
Pain related to cancer therapy
Pain related to indirect
mechanisms
CHARACTERISTICS OF CANCER
PAIN
PSYCHOLOGY OF CANCER PAIN
OVERVIEW OF CANCER PAIN
MANAGEMENT
APPROACHES TO THE
MANAGEMENT OF CANCER PAIN
Strategy for cancer pain
management
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132 Siu Lun TSUI, Chi Wai CHEUNG
Adverse Eects of Cancer Pain
Patient suering
Cancer pain not only causes physical discomfort, it aggravates
depression and other psychological distress. Pain often
disrupts the patient’s sleep and discourages the patient from
other daily activities. It has been shown that insomnia occurs
in 59% of cancer pain patients [58]. Pain either prevents
them from falling asleep and/or wakes them up during sleep.
is in conjunction with other physical disabilities seriously
impair the patient’s daytime performance. Pain fully occupies
the patient’s attention and causes fatigue, exhaustion,
anger and depression, rendering patients more irritable and
aggravating family stress. is further impairs the patient’s
social well-being, ending in a vicious cycle of increasing
overall suffering.
Inuence on hospital resources and
society
It is highly preferable for the cancer patient to be managed
at home if feasible [78]. ese patients can stay with their
families or even take employment if their physical status and
social environments allow. Most cancer patients who are not
physically debilitated or undergoing aggressive anti-cancer
therapy can be managed as outpatients. Often it is the pain
that keeps them hospitalised or forces them to make frequent
visits to the emergency department for analgesia and increases
the need for hospital resources and health care cost.
Pathophysiological Mechanisms of
Cancer Pain
Multiple mechanisms contribute to pain in a cancer patient.
ese can be categorised into pain as a result of the direct
effect of the malignant infiltration; pain due to complications
of anti-cancer therapy; and pain that is not directly related to
the above-mentioned factors. It should be noted that more
than one mechanism often occurs simultaneously in the same
patient [138]. It is important to carefully analyse and identify
each component so that specific treatment can be offered
accordingly.
Pain mechanism at the molecular level
Both tumour cells and macrophages have been shown to
secrete chemicals which can excite the primary afferent
nociceptors and induce inflammation. Schwei et al. [79]
used a murine model of bone cancer pain to demonstrate
Assessment and evaluation of
cancer pain
Planning for cancer pain
management
TREATMENT OF CANCER PAIN
SYSTEMIC ANALGESIA
Choice of drugs
Opioid analgesics
Non-oral routes of systemic
medication
Non-steroidal anti-inflammatory
drugs and paracetamol
Other groups of drugs for cancer
pain management
Importance of analgesic coverage
when switching from one
regimen to another
NEURAXIAL ANALGESIA
Overview
Extradural versus intrathecal
routes
Spinal drug delivery systems
Choice of neuraxial medication
NEUROABLATIVE PROCEDURES
Introduction
Common neuroablative
procedures for cancer pain
management
Assessment before performing
neuroablative procedures
Limitations of neuroablative
procedures
PSYCHOLOGICAL MANAGEMENT
OF CANCER PAIN PATIENTS
CONTROL OF OTHER
DISCOMFORTS AND PALLIATIVE
CARE
CONCLUSION
REFERENCES
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Cancer Pain 133
the neurochemical and cellular reorganisation
of spinal cord. is model paralleled the clinical
condition of osteolytic bone cancer. Change was
observed 21 days after intramedullary injection of
osteolytic sarcoma cells into the femur. Progressive
bone destruction, elevated osteoclast activity
and nocifensive behaviours were noticed. With
the destruction of the bone, tumour cells came
into contact with the sensory nerve fibres in the
bone and the periosteum under the slightly acidic
extracellular pH. ese peripheral changes, in turn,
caused neurochemical reorganisation at the spinal
cord level. Exclusively ipsilateral to the side of bone
destruction, massive astrocyte hypertrophy without
neuronal loss and expression of the pro-hyperalgesic
peptide dynorphin and c-Fos protein were found
in a population of neurons located in the deep
spinal lamina. Moreover, non-noxious palpation of
the bone with cancer induced the internalisation
of substance P receptors and c-Fos expression in
lamina I neurons. Certain chemicals present in the
neuropathic state or inflammation were absent.
All these changes suggested bone cancer pain is a
unique pain state when compared with neuropathy
and inflammation.
Pain due to direct eects
of malignant tumour and
metastases
e direct effect of malignant tumour accounts
for about 70% of cancer pain (Table 9.01) [13].
Tumour growth at the primary or distant sites
have a direct effect on surrounding tissues. Volume
expansion in a rapid tumour growth stretches the
capsule of an internal organ. Direct mechanical
compression, infiltration or entrapment of nerve
and plexuses usually cause intractable pain [94,
126, 138, 141]. It is well known that primary or
metastatic bone tumours are particularly painful.
Relative movement of an unstable pathological
fracture is another common cause of intractable
pain [95]. is pain, which is also known as
incident pain, is notoriously difficult to control
[95].
Tumour mass may cause obstruction of a hollow
viscus and blood vessels, leading to distension and
ischaemia respectively. Tissue reactions resulting
from inflammation and necrosis of tumour cells
as well as surrounding tissues will lead to release
of algogenic substances such as cytokines and
ions. e latter excite nociceptor neurons through
vanilloid and ASIC3 receptors [94]. Secondary
infection often occurs in malignant ulcers on skin
or mucosal surfaces, resulting in lancinating pain
and producing foul smelly discharges. Also, pain
can be related to paraneoplastic neuropathy. Most
neurological paraneoplastic disorders are thought
to be caused by an autoimmune reaction directed
against “onconeural” antigens expressed by neurons
and tumour cells [40].
Pain related to cancer therapy
Pain due to cancer therapy occurs in about 20%
of patients [13]. is percentage is reported higher
(40%) in paediatric patients [87]. Pain can be
due to radiation therapy, chemotherapy or as a
consequence of surgical dissection (Table 9.02).
Chemotherapy-related pain can be due to
neuropathy or infection. Neurotoxicity can
be induced by treatment with anti-cancer
chemotherapeutic agents. e most commonly
reported agents are cisplatinum, vinca alkaloid and
paclitaxel [50, 16, 38]. Other chemotherapeutic
agents causing pain include ifosfamide, bortezomib,
cytarabine and antiganglioside-G-D2 monoclonal
antibody [38]. is neurotoxicity is dose dependent
and can be presented as peripheral neuropathy,
autonomic neuropathy, central neuropathy and
encephalopathy [137]. e risk is higher with
co-administration of these agents, and in patients
with diabetic or alcoholic neuropathy [38].
Table 9.01 Cancer pain due to direct effects of
malignancy
1. Direct infiltration of tissues, bone and nerve
2. Mechanical pressure on surroundings, due
to tumour expansion, stretching of fascia and
capsule
3. Obstruction of hollow viscera
4. Ischaemia
5. Tissue inflammation and necrosis
6. Release of algogenic substances by tumour and
associated cells: prostaglandins, endothelin-1,
nerve growth factor, hydrogen ion, potassium
7. Osteoclastic resorption of bone, microfractures
and unstable pathological fracture
8. Secondary infection, open ulcer formation
9. Raised intracranial pressure
10. Paraneoplastic neuropathy.
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134 Siu Lun TSUI, Chi Wai CHEUNG
Neurotoxicity is commonly manifested as sensory
dysaesthesia, motor disturbance and hyporeflexia.
e pain is commonly tingling, burning, cramping
or electric-shock-like in nature. Acute herpes zoster
infection may occur during chemotherapy [88], and
is extremely painful and often leads to postherpetic
neuralgia, especially in patients of advanced age.
Oral mucositis is another common complication
of chemotherapy and radiotherapy, especially in
patients preparing for bone marrow transplant. is
usually occurs within 1 to 2 weeks of commencement
of therapy and can be very distressful to the patient.
It presents as painful inflammation of the oral
mucosa, often involving the pharynx and extending
to the oesophagus. e pain is usually severe and
aggravated by swallowing, thus preventing the
patient from having oral intake [154].
Complications of radiotherapy frequently
cause pain. e mechanisms include tissue
inflammation, fibrosis and necrosis and radiation-
induced peripheral neuropathy. Although neurons
are relatively less vulnerable to radiation than
tissues with rapid turn-over (like gastrointestinal
mucosa and bone marrow), radiation injury
to axonal supporting tissue like Schwann cells
and local blood vessels can also contribute to
neuropathy [38]. Radiotherapy used in treating
chest or breast tumours commonly causes
brachial plexopathy [115]. Irradiation to pelvic
tumours often causes lumbosacral plexopathy.
It is important to differentiate plexopathy
complicating radiotherapy from that due to
infiltration by tumour [13].
Surgical treatment can be a cause of pain in cancer
patient. In addition to the intense but transient
postoperative pain, chronic pain may develop after
some operations. One common example is pain
due to neuroma formation, such as intercostal
neuralgia after thoracotomy, or stump pain or
phantom pain after amputation and mastectomy.
Post-thoracotomy pain syndrome (PTPS) occurs
in about 50% of patients, in which 30% become
chronic [64]. Post-mastectomy pain syndrome
(PMPS) occurs in 4–20% of patients. e pain
usually consists of nocigenic and neuropathic
elements, which is due to damage of the
intercostobrachial nerve and may present with
tightness, burning or lancinating characteristics
associated with paraesthesia [131]. Both PTPS
and PMPS can cause frozen shoulders as the pain
prohibits mobilisation of the upper limbs [107].
Pain related to indirect
mechanisms
Apart from the above-mentioned mechanisms,
pain can also result from other indirect causes
(Table 9.03). Constipation is common in
cancer patients, especially in those taking opioid
analgesics. Constipation commonly causes vague
abdominal discomfort and even pain. Myofascial
pain may develop as a result of adopting special
posture to avoid pain resulting from unstable
pathological fracture or tumour mass. Adopting
such postures is likely to cause muscular pain
due to long term abnormal stresses in muscles
and tendons. Prolonged immobilisation due to
cachexia, general debilitation or therapy-related
complication also aggravates myofascial pain. In
Table 9.02 Pain due to cancer therapy
1. Radiation-induced cancer pain
(a) Plexopathy: brachial plexopathy,
lumbosacral plexopathy
(b) Myelopathy
(c) Osteoradionecrosis
(d) Haemorrhagic cystitis
2. Pain related to chemotherapy
(a) Neuropathy: cisplatinum, vinca alkaloid,
paclitaxel
(b) Mucositis in oral cavity
(c) Infections: herpes zoster
3. Pain due to consequences of surgery
(a) Acute wound pain
(b) Neuroma formation, PTPS, PMPS
(c) Phantom pain after amputation.
Table 9.03 Indirect mechanisms causing pain in
cancer patients
1. Constipation
(a) Dehydration
(b) Opioid analgesic
2. Neuromuscular pain
(a) Adopting posture to cope with disabilities
and to avoid pain
(b) Bedridden, prolonged immobility
3. Decubitus ulcer, bedsore due to impaired
mobility
4. General debilitation in cachexic patient with
advanced cancer
5. Psychological distress complicating cancer
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Cancer Pain 135
addition, these factors also contribute to formation
of painful decubitus ulcers.
Characteristics of Cancer
Pain
Cancer pain differs from chronic non-cancer pain in
several aspects. Firstly, the cancer and its metastases
are dynamic and progressive, unlike chronic pain
whose underlying pathology is relatively static.
New pathological mechanisms occur from time
to time to aggravate the existing pain, causing
new types of pain as well as affecting new sites.
e progressive development of pain-producing
mechanisms inevitably imposes greater difficulties
in analgesia. It is common that cancer pain patients
need progressively higher doses of analgesic and
escalate to more potent opioids. is is due to the
development of tolerance to analgesics, as well as
the appearance of new pain as a result of further
tumour progression and metastases.
Secondly, the extensive interaction of physical
with psychological elements, such as depression,
anxiety and anger, pose more challenges in pain
management. Patients with incurable cancer are
facing impending death. eir fear of intractable
pain and other symptoms towards death
accompanies the despair for cure. ese together
with social and economical burdens resulting from
the diseases impose extreme psychological distress
on the patient (see below). Failure to acknowledge
this fact will cause more difficulties in cancer pain
management.
irdly, in view of the patient’s limited life
expectancy and the extent of suffering, clinicians
tend to adopt a more aggressive approach in
treating cancer pain. is can be reflected in the
readiness to prescribe potent opioids and perform
neuroablative procedures to control pain.
Fourthly, cancer patients also commonly suffer
from other discomforts and disabilities in addition
to pain. In an analysis of 1,635 cancer patients
referred to a pain clinic in Germany, Grond found
that the patients suffered an average of 3.3 symptoms
in addition to pain [58]. is included insomnia
(59%), anorexia (48%), constipation (33%),
sweating (28%), nausea (27%), dyspnoea (24%),
dysphagia (20%), neuropsychiatric symptoms
(20%), vomiting (20%), urinary symptoms (14%),
dyspepsia (11%), paresis (10%), diarrhoea (6%),
pruritus (6%) and dermatological symptoms
(3%). It is important to treat all the discomforts in
addition to pain in cancer patients. Please also refer
to Chapter 33 for more details.
Psychology of Cancer Pain
Once cancer is diagnosed, the psychological impact
on patients is tremendous. Cancer patients worry
about death and dying, distressing symptoms
like pain, unresolved family issues and sometimes
hopelessness. is psychological distress exacerbates
pain, whereas pain in turn aggravates psychological
disturbance. Coping strategy is often developed to
deal with the diagnosis of cancer, but it differs among
different patients. e most common mechanisms
of defence are repression, denial, displacement,
projection and regression. Denial is an early and
common form of the coping process. e patients
may live normally as if unaware of the diagnosis.
It is maladaptive if the physical well-being and the
prognosis of the patients are jeopardised [145].
is maladaptive strategy can lead to short-term
relief with greater difficulties in the long term.
Cancer patients may be preoccupied with the
uncertain future, deteriorating disease progress, loss
of function, uncontrolled symptoms and signs, and
family issues. Fear may set in, which can generate
high anxiety and results in poor coping strategies
[6]. Pain, as well as fear, can also cause avoidance
and result in disability. Patients suffering from
cancer pain or treatment-related pain are more
likely to be anxious than cancer patients without
pain [132]. Anxiety can reduce the threshold
towards pain and make the resolution difficult [75].
e pain perception and response to treatment can
also be influenced.
Depression is particularly common among cancer
pain patients. It has been reported that 25% of all
cancer patients have depression, this increases to
77% for those with advanced disease [12]. Features
of depression include marked loss of interest in daily
activities, psychomotor retardation and feelings of
worthlessness. e ability to think is diminished
and concentration impaired. e prevalence of
depression among cancer patients increases with
disease severity and symptoms such as pain [122].
Pain-depression-fatigue cluster is also more prevalent
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136 Siu Lun TSUI, Chi Wai CHEUNG
in cancer pain patients [109]. However, Sze et al.
found severity of pain and impaired activity of
daily living did not correlate with depression [128].
e development of hopelessness and helplessness
is strongly linked to depression [6]. Hopelessness
is also the bridge between depression and suicide.
e cognitive dimension of pain is correlated with
hope [20]; therefore, the role of cognition for the
psychological well-being of cancer pain patients is
very important. Uncontrolled pain, psychological
distress such as depression, and existing suffering
are often related in cancer pain patients [27, 47].
Cancer and cancer pain not only affect the patients
but also their family members. Financial strain,
increased care tasks due to deteriorating disease
process and psychological distress due to dying of
significant others are common issues they often
face. e family caregivers may develop a high level
of psychological disturbance, especially when the
patients lose autonomy [39]. Depression that relates
to the patients’ symptoms and employment status
are also common among the family members of
cancer patients [53]. However, although the heavy
care tasks may have a negative effect on caregiver
health, schedule, anxiety and energy, they find their
roles meaningful [2].
Overview of Cancer Pain
Management
Although there is a strong evidence to support that
many cancer pain interventions [15] and guideline-
based treatment methods [19] can significantly
improve pain and outcomes, under-treatment
of cancer pain persists in various clinical setting.
Sydney and colleagues reviewed the standards for
cancer pain management based on current evidence
[41]. ey proposed that key standards for cancer
pain management should include screening,
assessment, general management of associated
symptoms and issues, addressing specific pain
syndromes and follow-up.
Pain guidelines recommend routine pain screening
[23, 74]. With a positive screen, assessment of
intensity, likely aetiology [90] and functional
ability [123] should be done. Patients should
receive routine pain education [1]. Symptomatic
treatment of severe cancer pain should begin with
opioid, regardless of the mechanism of the pain [22].
Long-acting opioid formulations should be used
with breakthrough opioids [90]. Other adjuvant
medications and therapies can be considered
[22]. Adverse effects of pain management such as
constipation should be addressed. Continuity of
opioid doses across health care setting should be
maintained [90]. Follow-up is important because
in order to have good pain control, adjustment of
pain medications, trying other treatment modalities
and management of adverse effects are mandatory
[90]. Attention should be paid to specific pain
syndromes such as metastatic bone pain and spinal
cord compression [41].
In concert with the World Health Organization
(WHO) analgesic ladder, a multidimensional
approach including tumouricidal, surgical,
interventional, radiotherapeutic, psychological
and rehabilitative modalities can offer the maximal
analgesia and minimal adverse effects [22]. All pain
clinicians should make the control of cancer pain a
professional duty and the goal of “no cancer patient
should live or die with unrelieved pain” will become
closer and closer [72].
Approaches to the
Management of Cancer Pain
Strategy for cancer pain
management
A holistic approach is adopted in the management
of cancer pain and other discomforts (Table 9.04)
[134, 135]. Symptomatic treatment of pain cannot
be separated from other treatment modalities. ese
include curative or palliative anti-cancer therapy,
treatment of other symptoms in addition to pain
control, care of the patient at home or in a hospice
and social assistance to the family. Modern cancer
pain management is a multidisciplinary task. e
basic involvement will include an oncologist to
provide primary treatment of the malignancy, a pain
specialist and palliative care physician to manage
pain and other symptoms, a clinical psychologist
to take care of the psychological features and allied
health care professionals to look after the physical,
functional and social aspects. A team approach is a
logical, feasible and cost-effective way to deal with
a large number of cancer patients. is necessitates
a system of patient referral, assessment, evaluation,
provision of treatment and monitoring of progress.
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Cancer Pain 137
Resource constraints may make it difficult to see
every cancer pain patient in a multidisciplinary
clinic involving different specialists simultaneously.
erefore, a good communication and referral
system enhances good quality of patient care
and avoids unnecessary delay in initiating the
appropriate treatment. Simple straightforward
cases can be screened and followed up by the
oncologists. Patients with specific problems are
referred to the relevant clinicians. ose difficult
cases with multiple problems are best managed in
a multidisciplinary clinic. e steps to manage a
patient with cancer pain are outlined in Fig. 9.01.
Assessment and evaluation of
cancer pain
e first step to manage cancer pain is a
comprehensive assessment of the patient [55]. is
commences with an assessment of the underlying
disease. e type of malignancy, the stage and extent
of involvement as well as the plan of treatment by
the oncologists should be studied in detail. Anti-
cancer therapy interacts with pain treatment and
affects the clinical decision for the latter. Anti-cancer
treatments such as radiotherapy or chemotherapy,
whether curative or palliative, often relieve the
pain. It has been estimated that 75% of cases will
have good quality of pain relief after radiotherapy.
Symptomatic pain treatment measures in such
circumstances serve as an adjunct to bridge the
time gap before anti-cancer therapy is effective.
Subsequent reduction of the analgesic dose may
be possible when the therapy starts to work. More
aggressive pain therapies, such as neuroablative
procedures, are not generally considered in such
circumstances. However, in cases where the cancer
is not amenable to anti-cancer therapy, pain and
symptom management become the mainstay in
the patient’s management. e progress of the
malignancy and anti-cancer therapy also affect the
pain management through their influence on major
organ function. For example, renal impairment due
to disease progress or chemotherapy (e.g. cisplatin)
may render the patient more intolerant to the usual
analgesic regimen [98].
e assessment of the pain itself is most effectively
conducted using special tools (see Chapter 3)
in the form of a checklist or questionnaire.
Patient evaluation should include the anatomical
location(s), character, nature, intensity of the pain,
whether it is intermittent or continuous, the timing
of symptoms as well as the aggravating and relieving
factors. Body movement or change in posture
which provokes pain, referred to as incident pain,
can be due to an unstable pathological fracture
as a result of tumour infiltration. Immobilisation
of the pathological fracture or avoidance of pain
triggering posture is effective in preventing
incident pain. e impact of pain on sleep and the
ability to perform daily activities are also important
data for baseline and subsequent assessment. It is
common to document the intensity of pain using
unidimensional or multidimensional scales. e
former is more simple and convenient, but is
unable to give a comprehensive picture of pain,
given the fact that pain by definition comprises
sensory, emotional and cognitive dimensions [63].
e unidimensional scales commonly used are the
Numerical Rating Scale, verbal rating score and
visual analogue scale (VAS) of pain [5, 65]. Since
pain has several dimensions, multidimensional scales
allow the clinician to understand more thoroughly
the patient’s pain with respect to its sensory,
affective and cognitive aspects. ese scales are more
comprehensive, but the assessment is more time
consuming. Commonly used multidimensional
scales are the McGill Pain Questionnaire [83],
Wisconsin Brief Pain Inventory [32] and versions
Table 9.04 Management strategy
1. Thorough assessment of cancer and its related
symptoms
2. Treatment of underlying pathology: curative or
palliative
(a) Surgical operation
(b) Radiotherapy
(c) Chemotherapy
(d) Hormonal therapy
3. Pain management
(a) Systemic analgesia
(b) Interventional procedures
(c) Spinal opioids
4. Management of other symptoms
(a) Constipation
(b) Dyspnoea
(c) Abdominal distension due to ascites
(d) Anorexia, emesis
(e) Cachexia
5. Preservation of functions
6. Psychological management
7. Social and familial management
8. Thorough understanding of the patient’s
underlying disease, morbidities, current
treatment and interaction of these factors.
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138 Siu Lun TSUI, Chi Wai CHEUNG
for different ethnic groups [144]. Other tools such
as the Memorial Pain Assessment Card and the
Edmonton Symptom Assessment System (ESAS) are
also useful in assessing the patient under palliative
care [11, 46, 48]. e latter consists of a series of
visual analogue scales developed for use in assessing
the levels of pain, activity, nausea, depression,
anxiety, drowsiness, appetite and sensation of well-
being as well as shortness of breath. e ESAS has
been validated in recent studies [18, 89].
Apart from the pain itself, the assessment of other
symptoms is equally important. It is wrong to just
focus on one symptom (pain) while the patient’s
distress as a whole is not adequately addressed.
Common distressful physical symptoms in cancer
pain include anorexia, nausea, emesis, constipation,
insomnia, impaired consciousness, dyspnoea, ascites,
fatigue, cachexia, paralysis and incontinence [46].
Interaction of these factors affects pain treatment,
either through interference with analgesic dose,
route of delivery or choice of interventional
procedure. Psychological distress such as depression
and anxiety inevitably affect the cancer pain patient.
It is mandatory to assess and evaluate the extent of
depression, anxiety, anger, irritability and apathy
so that necessary psychological intervention is not
delayed. e assessment of the patient’s functional
status is also essential because the cancer and its
treatment may result in functional disabilities.
When formulating the patient’s management plan,
the clinician should note the patient’s activities of
daily living (ADL), self-care or even ability to do
housework, and employment status. In choosing
an appropriate potent opioid dose regimen for pain
control, the clinician should also consider carefully
the implication of excessive daytime somnolence
that may prohibit the patient from undertaking
routine daily activities [46]. Also, the clinician may
be more likely to perform a neurolytic subarachnoid
block in a patient who is suffering from intractable
perineal pain, who is already paraplegic.
Modern management of cancer pain involves the
patient’s family [46]. It is essential to accurately
evaluate the availability of family support, marital
status and the financial situation when therapy
is planned. Some pain therapies involve the
implantation of a drug delivery device and require
frequent regular percutaneous injections. Home
care is feasible with the assistance of a competent
member of the family. Otherwise this type of
therapy can only be possible with the availability of
community nursing support or the patient has to
be managed in an institution. A supportive family
often allows an ADL-dependent cancer patient to
be nursed at home, with reasonable quality of life
and less health care costs.
Planning for cancer pain
management
e first step is the setting of a goal. Although the
prognosis of curing the underlying disease is often
poor, the prognosis of symptomatic relief is often
good. e patient should be reassured that the
control of their symptoms is likely to be successful,
although complete elimination of pain is often
not possible. Setting of treatment goals should be
directed to a reduction in pain intensity and other
discomforts. It is our common practice to set our
goal arbitrarily on a reduction of pain intensity by at
least 50% or to a VAS of less than 30/100, the ability
to sleep at night but with avoidance of excessive
somnolence during daytime, as well as minimising
anorexia, nausea and emesis. e treatment plan
should be explained in detail to the patient and
the family [46]; this includes elaboration on the
therapy, side effects and possible complications.
e patient and family should also be informed of
any contingency plans and alternative treatments
that are available, should initial therapy fail. ese
help to build up better rapport and enhance the
patient’s confidence, and to avoid unnecessary
confrontation should the pain relief fail to reach
the patient’s expectation. It is natural that a patient
expects a complete abolishment of pain and other
distressful symptoms. In reality, this is often
difficult to achieve despite aggressive treatment.
is fact should be delivered to the patients during
their early visits as any false hope is counter-
productive. On the other hand, the patient should
be reassured that it is not difficult to control the
pain to a tolerable level so as to cope with relatively
normal daily activities.
Treatment of Cancer Pain
Anti-cancer therapy is particularly effective in
relieving pain. Although in many cases cure is
impossible, palliative operation, radiotherapy and
chemotherapy often relieve the pain if the tumour
is responsive. Symptomatic pain management
(analgesics and interventional procedures) serves
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Cancer Pain 139
Figure 9.01 Flow chart to show the steps in managing cancer pain [133]. NSAID = non-steroidal anti-
inflammatory drug; PCA = patient-controlled analgesia.
Patient assessment
Evaluation and planning
Cancer pain management
Note: Although this flow chart is outlined in a stepwise fashion, the clinician
should choose the appropriate starting point depending on the individual
patient’s pain intensity and clinical situation. Strict adherence to the steps
may delay effective analgesia.
Anti-cancer therapy Management of other
discomforts
Psychosocial
management
NSAIDs, co-analgesics, mild opioid analgesics
Oral potent opioid analgesics,
+/- co-analgesics, +/- NSAIDs
Parenteral potent analgesics:
oral, transdermal, rectal, nasal, PCA, subcutaneous,
intravenous +/- co-analgesics, +/-NSAIDs
Neuroablative procedures Neuraxial analgesia
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