++
Painful varicella-zoster reactivation causes a dermatomal rash
and neuropathic pain. It occurs two to three times as frequently
in cancer patients as in the general population. Lymphoma and breast cancers
cause a disproportionate number of cases. The dermatome involved
is likely to correlate with the site of primary tumor in breast,
lung, and gynecologic cancer.44 Advancing age,
the severity of the initial rash and pain, and an ophthalmic distribution
predispose to the later development of postherpetic neuralgia. Cancer
does not appear to increase the likelihood of postherpetic neuralgia
when age is accounted for.45 A thorough review
of zoster and related pain is provided in another chapter (See Chapter 40, Acute Herpes Zoster and Postherpetic Neuralgia).
+++
Abdominal and
Pelvic Pain
++
In a review of 5675 patients presenting with acute abdominal
pain to a group of five European hospitals, 106 (1.9%)
were eventually found to have intraabdominal cancer. The risk of
cancer for those over 50 years old was 10%.46 Abdominal
pain from cancer is typically visceral in nature. As such, it is
poorly localized and often referred to distant sites, and often
accompanied by nausea and vomiting. Diaphragmatic irritation and
distension of the hepatic capsule produce ipsilateral shoulder pain,
retroperitoneal tumor may cause back pain, and pelvic tumor may
cause perineal pain. Viscus or duct blockage and distension, peritoneal
inflammation or tension, mesenteric torsion, and vascular or lymphatic obstruction
typically produce pain. Pelvic cancer pain occurs primarily in patients
with malignancies of the rectum and genitourinary tracts. Extra-abdominal
cancers also often metastasize to the sacrum and pelvis.
++
Abdominal pain not directly caused by intraperitoneal or retroperitoneal
malignancy is also common. Radiation-induced enteritis occurs in
acute and chronic forms. Acute injury manifests as abdominal or
pelvic pain, diarrhea, or tenesmus in up to one half of patients.
Chronic injury, occurring in 2% to 5% of patients,
presents as stricture, bleeding, perforation, or fistula 6 to 24 months
after radiation. Pain may be associated with bowel ischemia, obstruction,
or intraabdominal infection in patients with chronic enteritis.47 Pain
may radiate or refer to the abdomen from destructive low thoracic
and high lumbar spine disease and nerve root compression. Following
abdominal surgery for cancer, adhesions may form and cause painful
bowel obstruction.
++
Pain from pancreatic cancer is of particular interest because
of its frequency, severity, and amenability to celiac plexus block.
Up to 80% of patients with this disease present with significant
pain. With advanced disease, the figure rises to 90%, and
probably represents gastric or retroperitoneal invasion. Most tumors
are at the head of the gland, and may cause bile duct obstruction
early in the disease. Pain from the pancreatic head localizes to
the right epigastrium, whereas that from the body is felt in the
mid-epigastrium, and tumor in the tail produces pain in the left
epigastrium and posterior intercostal space.48
++
In about 70% of patients, chemoradiotherapeutic conditioning
for bone marrow or stem cell transplantation causes noninfectious
mucositis (stomatitis) by killing cells with high mitotic rates.49 Several
days following conditioning, hemorrhagic degradation and ulceration
of the oropharyngeal mucosa begins. While initially causing constant
mild or moderate burning discomfort, the condition progresses to
preclude talking, eating, or swallowing. Significant pain requiring
opioid use persists in one half of patients at 3 weeks after transplant.50 Mucositis
from head and neck radiation usually develops in the second or third
week of therapy, affects almost all patients, and is otherwise similar
to that from bone marrow conditioning. Normal doses of chemotherapeutic agents
also cause mucositis in about 40% of patients.49 Pain
may be more severe or prolonged when mucosal ulcers become superinfected
with bacteria or fungus, and when graft-versus-host disease occurs.
Reactivation of herpes simplex, cytomegalovirus, or varicella-zoster
infections in the immunocompromised cancer patient may present with vesiculo-ulcerative
mucositis.
+++
Chronic Postsurgical
Pain
++
Four postsurgical chronic pain syndromes have been identified.
They result from injury to nerve or plexus, so the pain is neuropathic
in nature.
++
Burning, aching, and tight constriction of the axilla, medial
upper arm, and chest with superimposed lancinations and scar sensitivity
are characteristic of postmastectomy pain. Phantom breast pain is
also described, and uncomfortable lymphedema of the arm is common.
Whereas previously less than 10% of mastectomy patients
were said to develop chronic pain,23 one half of
467 mastectomy patients recently surveyed went on to develop pain,
paresthesias, and phantom sensations.51 Less extensive
surgery was more often associated with pain in the ipsilateral arm.
In fact, the radiation and chemotherapy that followed less extensive
surgery were probably responsible for much of the arm pain. Progressive
pain was more common in patients with recurrent disease.
++
Maunsell and colleagues studied arm symptoms in 223 women who
underwent breast surgery with or without axillary dissection.52 About
one half complained of arm pain at 3 months postoperatively, and
a similar proportion at 15 months. Patients who had axillary dissection
were more likely to have arm pain, although this result did not
reach statistical significance. Wallace and colleagues also found
that breast reconstruction with implants after mastectomy increases
the likelihood of chronic pain from about 30% (mastectomy
alone or with simple reconstruction) to 50%.53 Submuscular
implant placement may injure the long thoracic, thoracodorsal, lateral
pectoral, and medial pectoral nerves. Capsule formation around the
implant may entrap the long thoracic and the two pectoral nerves.
++
Evaluation of chest and arm pain after mastectomy should focus
on the nature of the pain and its location, as well as neurologic
examination to define the areas of sensory loss and hypersensitivity.
A neuroma is sought in the chest wall and axilla. Autonomic changes
and limited shoulder motion may be present in the “frozen
shoulder” syndrome. Scapular winging is seen when the long
thoracic nerve has been disrupted. Pain that is not typical of postmastectomy
pain syndrome should prompt evaluation for infection and tumor recurrence.
++
During radical neck dissection, the superficial cervical plexus
is dissected out. The result is often neuropathic pain and sensory
loss in the anterolateral neck and extending to the shoulder. Division
of the accessory nerve and removal of the sternocleidomastoid muscle
may also lead to chronic pain via postural changes that affect the
shoulder girdle and entrap the upper brachial plexus.23 Loss
of trapezius function leads to drooping of the shoulder, mild scapular
winging, inability to abduct the shoulder above 90°, and forward
rotation of the scapula, often with sternoclavicular subluxation
(Fig. 44-2).54 Frozen shoulder often develops as
a result of weakness and pain.55
++
++
Ewing and Martin described 100 radical neck dissection patients
in 1952.54 Of 89 with unilateral operations, 42
patients had persistent shoulder pain. In two more recent studies,
76 of 100 radical neck dissection patients had shoulder pain and
dysfunction when evaluated at least 6 months after surgery.57,58 In
31, the pain was severe. The deep cervical plexus innervates enough
of the trapezius muscle to maintain shoulder mobility and prevent
shoulder-arm pain in some patients.58 Any patient
who has increasing pain following neck dissection should be evaluated
for infection and tumor recurrence.
++
Chronic chest pain after thoracotomy affects up to 55% of
patients followed for more than 1 year.59 Keller
and colleagues reviewed the records of 238 consecutive thoracotomy
patients.60 Post-thoracotomy pain was defined as
that requiring regular use of analgesics beyond 3 months from surgery.
Eleven percent of patients met this definition, but one half of
these used opioid analgesics preoperatively. Chest wall resection
and pleurectomy increased the likelihood of chronic pain when compared
with pulmonary resection. Importantly, all 20 patients with recurrence
of pain after initial control were found to have tumor regrowth.
The use of video-assisted thoracic surgery (VATS) for pulmonary
resection may decrease the incidence of chronic pain and disability
when compared with thoracotomy.61
++
Mechanisms for chronic pain after thoracotomy are several. The
intercostal nerves may be injured during rib resection, or compressed
with a retractor. Incidental rib fractures may entrap an intercostal
nerve during healing. These patients may develop dermatomal chest
wall numbness and neuropathic pain complaints, including point tenderness
from neuroma formation. Severe rib retraction may also disarticulate
the costochondral and costovertebral junctions, resulting in somatic
pain and tenderness. Because the latissimus dorsi and serratus anterior
muscles are often cut during thoracotomy, ipsilateral shoulder disability
is also common. Untreated thoracotomy pain and inadequate rehabilitation
may lead to frozen shoulder. Symptomatic myofascial trigger points
often develop in chest wall muscles. All patients with increasing
or recurrent pain after thoracotomy should be evaluated for tumor
and infection.60
++
Chronic pain following limb amputation is either stump pain or
phantom pain or both. Wartan and colleagues surveyed 590 war-related
amputees in England to assess the prevalence of chronic pain.62 Of
these, 55% reported phantom pain, and 56% had
stump pain. Sherman and colleagues surveyed 5000 American veterans
with amputations.63 Fifty-five percent responded,
and 78% of those reported phantom pain. Stump pain is due
to local disease, most commonly infection or neuroma formation.
Neuroma formation several weeks after amputation produces exquisite
stump tenderness and pain that is either constant or elicited by
palpation or movement. An ill-fitting prosthesis, recurrent tumor,
infection, or ischemia may also cause local pain and tenderness.64
++
Phantom sensation, the sensory experience that the amputated
limb is still present, occurs in most amputees. Phantom pain is
often described as a paroxysmal burning, crushing, and twisting
in the missing part. Phantom pain peaks in the first month after
surgery and may fade slowly as it “telescopes” toward
the stump.63 It is more common after more proximal
amputations.65 Patients with extremity pain prior
to amputation are more likely to develop immediate postamputation phantom
pain,66 and preemptive analgesia with lumbar epidural
blockade may reduce the incidence of phantom pain.67
++
Numerous neurophysiologic explanations for phantom pain have
been advanced, from changes at the stump to functional cortical
changes. Sensory deafferentation in primates and arm amputation in
humans causes cortical somatosensory reorganization.68 This
may explain the elicitation of phantom pain by sensory stimulation
at other sites. As with the other postsurgical pain syndromes, an
unexpected increase in or recurrence of pain should prompt evaluation
for infection, ischemia, or tumor recurrence.64,65