Spinal Cord Neoplasms Clinical Presentation

Back pain is the initial feature of spinal cord neoplastic disease in about 90% of adult patients. Pain often precedes other symptoms associated with spinal cord compression by approximately 2-4 months. Pain or discomfort may be radicular, localized to the back, or both. Radicular pain suggests nerve root impingement and may be exacerbated with movement or straining/valsalva.

As back pain has many causes, and spinal cord compression can have a subtle presentation, ^[4]  a high index of suspicion may be required when evaluating a patient with back pain and a history of malignancy.  An old clinical axiom is that pain from vertebral metastasis (particularly thoracic metastasis) may worsen with recumbent positioning—in contrast to back pain from degenerative joint disease, which may improve with recumbent positioning.

Once symptoms other than pain appear, symptom progression may be rapid. Sensory or motor symptoms that may be referred to the cord include limb paresthesias or focal weakness; the latter may manifest as trouble ambulating or foot drop (often bilateral).

Onset of leg weakness, paresthesias, or bowel or bladder dysfunction in patients with a history of cancer should evoke immediate concern for cord or cauda compression. Paraplegia and bowel or bladder disturbances are usually late findings. Urinary retention is the most common bowel or bladder dysfunction, but retention or incontinence of either urine or stool may occur. 

In conus medullaris syndrome, however, sphincter dysfunction and saddle anesthesia may emerge early in the course. Patients with conus medullaris syndrome classically present with low back pain and urinary andIor bowel dysfunction but no gross sensory or motor deficits. 

Other historical features that may raise the suspicion for neoplastic cord compression include the following:

• Unexplained weight loss
• Night pain
• Persistent pain that fails to improve despite appropriate workup and therapy

Findings on physical examination correspond to the location of the tumor and the degree and duration of cord impingement. and may include the following:

• Local tenderness
• Motor weakness
• Sensory loss
• Reflex changes
• Ataxia
• Cauda equina syndrome 

Tenderness

Severe spinal pain and tenderness is usually the first finding in neoplastic spinal cord disease. Percussion tenderness over the affected spinal region may be present. On straight-leg raising, pain that progresses down the asymptomatic (or less symptomatic) limb may suggest cord compression.

Valsalva maneuvers, such as coughing, sneezing, or straining, may exacerbate radicular back pain from cord compression, but this occurs with other causes of mechanical back pain as well.

Motor weakness

Motor weakness occurs late in the disease process, with thoracic or lumbar lesions causing lower extremity weakness, especially  of the flexors, and cervical lesions causing lower extremity weakness as well as upper extremity weakness, especially of the extensors.

Almost one-half of patients with neoplastic spinal cord compression have some paresis, with as many as 15% of patients being paraplegic at the time of diagnosis.

Lax anal sphincter tone is a late sign of spinal cord dysfunction.

Sensory loss

The loss of sensation below a spinal level may be present on exam, usually starting up to five dermatomes below the level of the offending lesion. Lesions above the conus typically spare the sacral dermatomes/saddle area, in contrast to lesions of the cauda equina (see cauda equina syndrome, below)

Reflexes 

Spinal cord compression may cause hyperreflexia below the level of the lesion. There may be a period of hyporeflexia early in the course, before the development of hyperreflexia.

Spasticity or hyperreflexia may occur early, or deep-tendon reflexes may be initially hypoactive or absent. The Babinski sign (upward movement of the toe in response to plantar stimulation) may be absent early in the course of compression.  As spinal cord compromise advances, hyperreflexia and Babinski reflexes are typically present.

Ataxia

Concomitant development of lower extremity weakness and sensory loss may cause ataxia or a gait disturbance. ^[4] Rarely, spinal cord neoplasms may present as isolated ataxia not due to sensory or motor deficits

Cauda equina syndrome

Patients with cauda equina syndrome may present with various patterns of lower extremity weakness and sensory loss, depending on which of the multiple nerve roots are compressed at the point where they exit the spinal cord. Manifestations may include bilateral lower extremity radicular pain, in addition to lower back pain. In contrast to lesions above the conus, cauda equina lesions result in hyporeflexia.

Additional findings in certain cases

Consider the following:

• Lateral spinal cord compression can produce partial cord disorders, such as Brown-Séquard syndrome (contralateral motor and sensory deficits).
• Lesions of the cauda equina and the termination of the spinal cord may cause a combination of upper motor neuron and lower motor neuron signs.
• Tumors in the region of the foramen magnum may produce quadriparesis and simulate other causes of diffuse weakness.
• If a cervical intramedullary tumor or syrinx (cavity) is present, the unusual clinical picture of isolated sensory loss may be present in the upper extremities.