Review Question - QID 217233

This patient presenting with lower extremity weakness, worsening back pain that is worse at night, hyperreflexia (ankle clonus), and upper motor neuron signs (an extensor plantar reflex) in the setting of an elevated PSA most likely has neoplastic spinal cord compression secondary to prostatic cancer metastases to the spinal cord.

Neoplastic metastases from any site to the spine can result in spinal cord compression, but most commonly involve primary prostate, lung, and breast cancers. Patients with spinal cord compression present with progressive and severe back pain that is worse while lying down or at night, lower extremity weakness, hyperreflexia in the lower extremities, and a positive Babinski sign (extensor plantar reflex). Bowel and bladder dysfunction may also be present but are typically late findings. Diagnosis can be confirmed with magnetic resonance imaging (MRI) of the entire spine with and without contrast. Treatment is directed at the underlying condition along with glucocorticoids to reduce edema for neoplastic lesions and analgesics for pain control. Additionally, surgical decompression with or without radiation may be indicated depending on the tumor's radiosensitivity, grade of compression, and stability of the spine.

Robson reviewed the clinical findings and treatment for metastatic spinal cord compression. The author emphasizes the importance of MRI for diagnosis. The authors recommend the prompt initiation of glucocorticoids in patients with MRI findings consistent with metastatic spinal cord compression.

Incorrect Answers:
Answer 1: Acute demyelinating inflammatory polyneuropathy, also known as Guillain-Barre syndrome, typically presents days to weeks after a gastrointestinal or genitourinary infection with ascending paralysis and areflexia. This patient’s motor weakness does not exhibit an ascending pattern and he has hyperreflexia, not areflexia.

Answer 2: Amyotrophic lateral sclerosis typically presents with asymmetric limb weakness and both upper and lower motor neuron findings. Lower motor neuron findings include muscle hypotonia, atrophy, hyporeflexia, and fasciculations. This patient has symmetric limb weakness and does not have lower motor neuron findings.

Answer 3: Multiple sclerosis typically presents in younger women with focal neurological deficits and lesions that are disseminated in both time and space. Examples include optic neuritis, paresthesias, focal weakness, and/or bowel or bladder dysfunction. Although there are multiple types of multiple sclerosis, symptoms typically exhibit a relapsing and remitting pattern. It is less likely in this elderly patient with prominent, progressive lower extremity symptoms.

Answer 5: Spinal epidural abscess can cause subacute-to-acute spinal cord compression. In addition to signs of spinal cord compression, it presents with fever, chills, and focal spinal tenderness at the site of the abscess. It is unlikely in this afebrile patient without risk factors for infection.

Bullet Summary:
Spinal cord compression can be caused by metastatic cancer and presents with progressive, severe back pain, lower extremity weakness and hyperreflexia, and/or a positive Babinski sign.