Learning Objectives: After reading this article, the physician should be able to:
1. Describe the wide range of oncologic emergencies seen in emergency department patients.
2. Summarize the treatment for various oncologic emergencies in ED patients.
3. Define the “wait-and-see” approach to pediatric otitis media and understand its potential benefits.
Release Date: June 2009
Article from the 2009 Reading List
Oncologic Emergencies: Diagnosis and Treatment
Halfdanarson TR, et al
Mayo Clin Proc
Hypercalcemia occurs in up to a third of cancer patients, and is most commonly associated with multiple myeloma, breast cancer, and lung cancer. Humoral hypercalcemia, mediated by elevated parathyroid hormone-related protein, is the most common cause of hypercalcemia of malignancy. Other causes include overproduction of vitamin D and bone resorption from cytokine-activated osteoclasts. Patients present with multiple nonspecific symptoms including lethargy, confusion, nausea, constipation, and polyuria.
Excessive fluid loss and impaired oral intake can result in severe dehydration. Hypercalcemia is diagnosed by measuring the serum ionized calcium. If the total serum calcium is measured, it must be corrected for the serum albumin using the formula: corrected calcium (mg/dl) = measured calcium + [0.8 × (4.0 – albumin)]. Large volumes of normal saline are often required to correct hypovolemia. Loop diuretics increase the renal excretion of calcium, but should be avoided until the patient is euvolemic. Bisphosphonates such as zoledronic acid and pamidronate block osteoclast resorption, and are the mainstay of therapy in the chronic management of malignancy-related hypercalcemia.
Tumor lysis syndrome is a spectrum of metabolic derangements most often seen after aggressive treatment of leukemias, lymphomas, and some solid tumors. After tumor cell death, intracellular contents such as uric acid, potassium, and phosphate are released. Hyperuricemia can cause renal failure, and hyperkalemia may lead to arrhythmias. High phosphorus levels can cause hypocalcemia and seizures. Tumor lysis syndrome is most common soon after recent initiation of chemotherapy. Laboratory values show increased serum lactate dehydrogenase, uric acid, potassium, and phosphate, and decreased serum calcium. Emergent treatment is supportive with a focus on correcting electrolyte abnormalities. Oncologists treat patients at risk for tumor lysis syndrome with allopurinol and intravenous hydration before initiating chemotherapy. Rasburicase is a recombinant intravenous urate oxidase used in patients with very high risk of hyperuricemia.
Malignant spinal cord compression can be caused by any malignancy, but is most common in breast, lung, and prostate cancers. Neurologic outcome is determined by the rapidity of symptom onset and functional status at presentation. Tumors erode into and encroach on the spinal cord, with the thoracic spine the most common site of malignant spinal cord compression. Almost all patients have back pain, but they also present with radicular pain, motor weakness, gait disturbance, and bowel or bladder dysfunction. Deficits at the time of presentation may not improve with treatment. Often the goal is to prevent further neurologic deterioration. In suspected malignant spinal cord compression, magnetic resonance imaging is the modality of choice. High-dose dexamethasone should be given immediately after diagnosis or if diagnostic imaging is delayed. Patients often require radiation therapy to ameliorate spinal cord compression by shrinking tumor size. Recent evidence suggests that patients who present with neurologic deficits may benefit from surgical tumor resection, and have improved outcome compared with patients who received radiation therapy alone.
Brain metastases can occur with any malignancy, but lung and breast cancer and melanoma most likely spread to the brain. Malignancies spread to the brain hematogenously, and are most often found at the grey-white matter junction. Ninety percent of brain metastases are supratentorial, and cause symptoms from edema and increased intracranial pressure. Only about half of patients with brain metastases have headache, but most present with symptoms of increased intracranial pressure or acute onset of seizure. CT scanning is less sensitive and specific than MRI for detecting brain metastases, especially in the posterior fossa. Brain metastases often indicate a poor prognosis, and treatment is often palliative. Increased intracranial pressure is treated with dexamethasone, the most lipid soluble of the glucocorticoids. Patients who are asymptomatic do not need steroid treatment, and only patients with seizures need prophylactic anticonvulsant therapy. Whole-brain radiation is used to treat brain metastases, with stereotactic radiosurgery being an option for some patients.
Malignant pericardial effusions are often seen in patients with advanced cancer, and portend a poor prognosis. Pericardial effusions are caused by pericardial metastases, direct invasion, or chemotherapy. Large or rapidly accumulating effusions can cause tamponade physiology. Patients present with shortness of breath, jugular venous distention, chest pain, lower extremity edema, hypotension, and shock. Echocardiography is the diagnostic modality of choice. Small asymptomatic effusions do not require treatment, but large or symptomatic effusions require drainage.
Superior vena cava (SVC) syndrome results from either intraluminal clot or extrinsic compression on the SVC, limiting blood return from the upper extremities. Malignancy is the leading cause, and thrombotic causes are often precipitated by an indwelling central venous catheter. Patients present with dyspnea, facial flushing, and cough worsened by leaning forward. Treatment strategies include clot removal, tumor shrinkage with radiation, and SVC stenting.
Hyperviscosity syndrome is caused by stasis of blood flow in patients with extremely high levels of circulating immunoglobulins, paraproteins, or leukocytes, as seen in patients with Waldenström macroglobulinemia, multiple myeloma, or leukemia. Clinical presentations are related to decreased end-organ perfusion and ischemia causing mucocutaneous bleeding, papilledema, and mental status changes. Plasmapheresis is effective in reducing paraprotein in hyperviscosity syndromes. Fever and pulmonary infiltrates with dyspnea are characteristic of severe leukostasis, and can make differentiating this entity from infection difficult. Leukopheresis can quickly reduce leukocytosis, and is indicated when the leukocyte count is greater than 100,000/mm3.
Neutropenic fever is defined as a single oral temperature greater than 38.3°C or a sustained temperature (longer than an hour) greater than 38.0°C, in addition to an absolute neutrophil count less than 1000/mm3. The neutrophil nadir usually occurs five to 10 days after the last chemotherapy dose. Both gram-positive and gram-negative organisms can cause infection in neutropenic patients. Common infections may present in an atypical faction in the neutropenic host, such as pneumonia without infiltrates or cellulitis without marked erythema. Patients with neutropenic fever should be pan-cultured, and receive immediate antibiotics. Single-drug therapy with a broad-spectrum agent such as cefipime, ceftazidime, or a carbapenem has been shown to be as effective as dual-drug therapy and associated with fewer adverse advents.
Article from the 2008 Reading List
Wait-and-See Prescription for the Treatment of Acute Otitis Media: A Randomized Controlled Trial
Spiro DM, et al
Otitis media is the most common diagnosis for children receiving antibiotics. A number of recent papers and subsequent guidelines have looked at avoiding antibiotics in cases where the etiology is likely viral to decrease cost and antibiotic overuse. This study looked at whether giving parents a “wait-and-see” prescription for antibiotics in children with uncomplicated otitis media was an alternative to a routine prescription for antimicrobial therapy.
Children 6 months to 12 years with otitis media presenting to an academic pediatric ED were eligible for the study. The diagnosis was made by the attending physician who had been given a review of recent evidence-based guidelines for treatment. Children were excluded from the study for concurrent bacterial infection such as pneumonia, toxic appearance, need for hospitalization, immunosuppression, treatment with antibiotics in the previous seven days, perforation of the tympanic membrane, or poor social support.
The authors of the study assessed 776 patients with acute otitis media, and randomized 283 patients. Some 138 patients were enrolled in the “wait-and-see” prescription group, and 145 were assigned to the standard prescription group. Patients assigned to “wait-and-see” were given an antibiotic prescription of the clinician's choosing, and told not to fill the prescription unless the child had not improved 48 hours after the visit. The standard prescription group received a prescription with explicit instructions to take the antibiotic after discharge from the emergency department. Both groups received analgesic otic drops and ibuprofen suspension with instructions to use these medications.
The primary outcome was the proportion of each group that filled the prescription for the antibiotic. Secondary outcomes included days of school missed, clinical course, unscheduled medical visits, and if the parents would be comfortable managing future episodes of otitis media without antibiotics.
No serious adverse events such as serious bacterial infection were reported in this study. Prescriptions were not filled in 62 percent of the “wait-and-see” group and 13 percent of patients in the standard prescription group. Parents in the “wait-and-see” group filled the prescription for fever (60%), otalgia (34%), or fussy behavior (6%). Interestingly, patients in the “wait-and-see” group whose parents filled the prescription reported more ear pain, fever, and diarrhea than those in the same group whose parents did not fill the prescription. For the secondary outcomes, patients were more likely to have diarrhea in the standard prescription group, but there were no statistically significant differences in the frequency of rash, otorrhea, or unscheduled follow-up visits between the two groups.
About the LLSA
As part of its continuous certification program, the American Board of Emergency Medicine has developed the Lifelong Learning and Self-Assessment (LLSA) program to promote continuous education of diplomates. Each year, beginning in 2004, 16 to 20 articles are chosen based on the Emergency Medicine Model. A list of these articles can be found on the ABEM web site, www.abem.org.
ABEM is not authorized to confer CME credit for the successful completion of the LLSA test, but it has no objection to physicians participating in such activities. EMN's CME activity, Living with the LLSA, is not affiliated with ABEM's LLSA program, and reading this article and completing the quiz does not count toward ABEM certification. Rather, participants may earn 1 CME credit from the Lippincott Continuing Medical Education Institute, Inc., for each completed EMN quiz.
CME Participation Instructions
To earn CME credit, you must read the article in Emergency Medicine News, and complete the quiz, answering at least 80 percent of the questions correctly. Mail the completed quiz with your check for $10 payable to the Lippincott Continuing Medical Education Institute, Inc., 770 Township Line Road, Suite 300, Yardley, PA 19067. Only the first entry will be considered for credit, and must be received by Lippincott Continuing Medical Education Institute, Inc., by June 30, 2010. Acknowledgement will be sent to you within six to eight weeks of participation.
Lippincott Continuing Medical Education Institute, Inc., is accredited by the Accreditation Council for Continuing Medical Education to provide medical education to physicians. Lippincott Continuing Medical Education Institute, Inc., designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit.™ Physicians should only claim credit commensurate with the extent of their participation in the activities.