Page 1269 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

876 PART 7: Hematologic and Oncologic Disorders

suggests direct invasion of the tumor into the epidural space; radicular, the patient’s overall status and prognosis before undergoing any surgical
which may be caused by impingement of nerve roots; and pain that procedure. 64
worsens with movement due to instability of the spine after vertebral Corticosteroids should be administered as soon as the diagnosis of
body collapse. Rodichok et al demonstrated that over 60% of patients MSCC is made. These agents not only decrease edema, but may also
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with cancer complaining of back pain had compression of the epidural have a direct effect on tumor destruction such as in cases of lymphoma.
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space by tumor even if no neurological deficits were present. Motor Sorensen et al reported that administration of intravenous IV dexa-
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deficits are also common during MSCC; 35% to 75% of patients com- methasone prior to radiotherapy and for a total of 10 days decreased
plain of a certain degree of weakness on presentation, and about 50% to pain and improved neurologic function. When comparing 100 mg iv
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68% of patients diagnosed with MSCC cannot walk before initiation of bolus to 10 mg iv bolus of dexamethasone, there was no difference in
treatment. 60,68 Hamamoto et al observed that motor deficits were present pain reduction, survival, or neurological outcome. 78
in 54% of patients with middle thoracic spine involvement, 30% with Spinal stereotactic radiosurgery, percutaneous vertebroplasty, and
lower lumbar spine, and 15% with cervical spine involvement. Sensory kyphoplasty are being considered more localized and less invasive methods
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deficits can also be present in about 50% to 70% of cases, but are usually of treatment of MSCC. While some studies have shown promising results,
not recognized by the patients. Autonomic dysfunction, presenting they are still not widely used and are still considered experimental. 64,79
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with bowel and bladder incontinence, occurs late in the progression of
disease and is a poor prognostic factor for recovery. 60,64,68 ■ INTRACRANIAL HEMORRHAGE
The gold standard for diagnosis of MSCC is MRI. Prior to MRI, spine The prevalence of cerebrovascular accidents in the oncological popula-
radiographs, CT scans, and myelograms were performed until studies tion is approximately 15%, with intracranial hemorrhage (ICH) being
proved that MRI was the most cost-effective method for diagnosis of more common than ischemic disease. 80-82 Hematologic cancer patients,
MSCC. All patients suspected with MSCC should have a whole spine when compared to patients with solid tumors, have a higher incidence
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MRI as 17% to 30% of patients have multiple spinal lesions. These of ICH and a worse outcome. In comparison to the general popula-
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lesions should be characterized for risk stratification for SCC. Patients tion, hypertension and amyloid angiopathy are rarely causes of ICH in
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with evidence of laminar involvement or metastasis in the midthoracic cancer patients. Table 93-2 lists the various causes of ICH in patients
spine can be high risk for MSCC and should be considered for early with malignancy.
intervention. Angiography is useful in hypervascular tumors such as The frequent occurrence of thrombocytopenia and coagulopathy in
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sarcoma, melanoma, thyroid, and renal cancer when embolization of hematologic cancer patients is a major contributor to the high prevalence
these tumors is considered prior to surgery. 62 of ICH in these patients. 80,83 Moreover, their hemorrhages are usually
Treatment of MSCC is an emergency and requires immediate and larger and can be fatal in over 70% of cases. 80,83,84 Particular populations
quick evaluation by a multidisciplinary team that includes oncologists, that are at increased risk of ICH are leukemic patients (especially those
radiation oncologists, and neurosurgeons. Survival after diagnosis of with acute promyelocytic leukemia [APML] and hematopoietic stem
MSCC is usually 3 to 6 months. 61,63 Treatment is therefore palliative cell transplant [HSCT] patients). In leukemic patients, hyperleukocy-
and should aim to decrease pain and preserve or restore neurologic tosis has been found to be a risk factor for ICH. 85,86 Hyperviscosity and
function. 62,64 Scoring systems have been created to evaluate the patient’s release of inflammatory factors such as intercellular adhesion molecule
prognosis and serve as a guide for treatment. 70-73 These scoring systems (ICAM), vascular cell adhesion molecule (VCAM), TNF-α, and IL-1β
include functional status, type of tumor, number of bone metastases, can lead to thrombosis and subsequent bleeding. Patients with APML
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degree of neurologic dysfunction, number of visceral metastases, and are at increased risk of ICH due to their high incidence of disseminated
response to radiotherapy. Harrington score classifies spinal metastasis intravascular coagulation on diagnosis (70%-80%). In the HSCT popu-
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according to the degree of neurologic dysfunction, and is used as a guide lation, risk factors for ICH include autologous transplant, graft-versus-
to select candidates for either surgery or radiotherapy. 74 host-disease, venoocclusive disease, and prior radiotherapy. 83,88
Radiation therapy has been the main treatment for MSCC since the Intracranial hemorrhages in solid tumor patients are usually tumor-
early 1950s. 60,73 Indications for radiation therapy include absence of related hemorrhages (TRH). The prevalence of macroscopic or micro-
spinal instability, patients unable to tolerate surgery due to poor func- scopic TRH is about 14%. 80,88 Metastatic tumors to the brain, such as
tional status, life expectancy less than 6 months, diffuse spinal disease, germ cell tumors, melanomas, lung, and papillary thyroid cancer, are
neurological deficit ongoing for over 24 to 48 hours, and sensitivity of more prone to bleed when compared to primary brain malignancies.
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the primary tumor to radiotherapy. Treatment with radiotherapy has Solid tumor-related hemorrhages have a better prognosis than ICH
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been effective in reducing pain, tumor size, and preserving neurologic associated with hematologic malignancies. 80,82 Moreover, when neuro-
function. Optimal dosing and frequency of radiotherapy have not been logic examination is unchanged from baseline, their prognosis is the
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well established since no studies have shown improved outcome when same as in patients with brain tumors that have not bled. 80,87
comparing different protocols. 75
Outcomes of patients undergoing surgical decompression have
improved significantly since the 1980s. Initial surgical interventions
consisted of only laminectomy; however, with new approaches, neuro- TABLE 93-2 Malignancy-Related Causes of Intracranial Hemorrhage
surgeons are able to decompress the spinal cord, perform cytoreduc-
tive resections to avoid recurrence, and reconstruct and stabilize the Tumor related Tumor-related hemorrhage
spine. 61,64 Indications for surgery include progression of tumor despite Invasion of dura
radiation, neurologic deterioration during radiation, significant cord Leptomeningeal disease
compression, medically intractable pain, radioresistant tumors, and Vascular Tumor-related arteriovenous malformation
evidence of spinal instability. In 2005, Patchell et al published the first Neoplastic aneurysms
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randomized clinical trial comparing the treatment of MSCC with radio- Infectious vasculitis/aneurysms
therapy alone versus radiotherapy combined with surgical intervention Treatment related Chemotherapy for acute promyelocytic leukemia
(generally within 24 hours). These investigators found that patients Radiation (intracerebral cavernous malformations)
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who had undergone surgical intervention and radiotherapy were more
likely to regain neurologic function (gait and urinary continence) had Hematologic Disseminated intravascular coagulation
better pain control, and improved survival than those receiving radia- Thrombocytopenia
tion alone. A meta-analysis by Klimo et al replicated these results. Leukostasis
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Despite these encouraging results, it is important to take into account Microangiopathic hemolytic anemia

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