Oncologic emergencies can result from either the cancer or its treatment. Cancer patients often have immunologic, metabolic, and hematologic defects, which can lead to complex emergency conditions when they present to an emergency center. In addition, emergencies resulting from comorbid conditions also occur in cancer patients. It is important for practitioners who treat patients with cancer to be aware of the various oncologic emergencies so that they can be recognized and treated promptly. This chapter discusses many of these emergencies, including their signs and symptoms, causes, and management.
Spinal Cord Compression
Spinal cord compression is a serious complication of cancer progression, affecting about 2.5% of cancer patients overall (1). It is not immediately life-threatening unless it involves the first three cervical vertebrae, but involvement in the rest of the spine leads to significant morbidity (2). The spinal cord is compressed at the thoracic vertebrae in 70% of patients, cervical vertebrae in 10% of patients, and lumbar vertebrae in 20% of patients. In 10% to 38% of cases, spinal cord compression occurs at multiple levels (3). Such compression is predominantly due to metastatic tumors, with lung, breast, and prostate cancer comprising 50% of these. Other tumors that commonly metastasize to the spine are multiple myeloma, renal cell carcinoma, melanoma, lymphoma, sarcoma, and gastrointestinal (GI) cancers. The mechanisms by which tumors can appear in the spine are hematogenous spread of tumor cells to the vertebral bodies, metastasis of primary lesions to the posterior spinal elements, and direct extension of paraspinal tumors. Spinal cord compression is caused by epidural metastases in 75% of cases and bony collapse in 25% of cases (4).
The most common presentation of spinal cord compression is back pain, occurring in over 90% of patients. Depending on the location of the tumor in the spinal canal, the pain can be unilateral or bilateral following dermatomal patterns. Patients typically report that their pain is worse when they are supine and better when they are upright. Ataxia due to compression of the spinocerebellar tracts can be confused with cerebellar metastasis, overmedication with analgesics, or other disorders. Metastasis to the spinal cord can precede spinal cord compression by weeks or months. The patient may also note sensory symptoms, including numbness or tingling in the toes, which can progress proximally. Preexisting peripheral neuropathy must be differentiated from spinal cord compression and acute worsening of existing symptoms or experienced new numbness or tingling. Motor symptoms are the second most common complaint after pain; difficulty walking, buckling under of the legs, and a feeling of heaviness in the legs are all frequent symptoms. The last symptoms to appear are autonomic symptoms, such as urinary retention and constipation. Autonomic symptoms are late findings in spinal cord compression and must be distinguished from the effects of chemotherapy, pain medicines, and antihistamines. It ...