Acute leukemia is the most common malignancy in childhood and may present with a variety of symptoms including fever, fatigue, bleeding, adenopathy, or bone pain.
Most oncologic emergencies arise from metabolic, hematologic, structural, or toxic chemotherapy effects.
Findings associated with inflammation may be absent in the immunocompromised patient, with fever potentially the only sign of serious infection. However, immunocompromised patients may have serious infections without the presence of fever.
Infection may progress rapidly in the immunocompromised host; evaluation and initiation of antibiotic therapy must be done urgently.
Tumor lysis syndrome (TLS) results from the death of tumor cells and release of their intracellular contents leading to hyperuricemia, hyperphosphatemia, and hyperkalemia.
Mediastinal compression from tumor may result in superior vena cava syndrome (SVCS) or superior mediastinal syndrome (SMS), resulting in an airway emergency.
Approximately 10% of childhood deaths are related to cancer.1 Acute leukemia, central nervous system (CNS) tumors, and lymphomas account for more than one-half of all childhood malignancies. Advances in cancer treatment have led to improvement in survival rates. However, this progress has often come with increased intensity of treatment regimens, with concomitant increase in possible toxicity. It is important for the emergency physician to be aware of the common malignancies that occur in children and to be ready to treat the complications of cancer at presentation and during treatment.
COMMON PEDIATRIC MALIGNANCIES
Leukemia is a condition in which there is uncontrolled, clonal proliferation of an immature white blood cell (WBC) within the bone marrow, with subsequent suppression of normal hematopoiesis. Acute leukemia is the most common childhood malignancy, with an incidence of approximately 30 cases per million persons younger than 20 years of age.2 Acute lymphoblastic leukemia (ALL) accounts for approximately 75% of pediatric leukemia, with acute myelogenous leukemia (AML) accounting for the other 25%. Chronic myelogenous leukemia (CML) accounts for less than 1% of all childhood cancers.
The peak incidence of ALL in children occurs between the ages of 3 and 5 years. Overall, greater than 80% of patients survive more than 5 years beyond diagnosis, with many patients considered cured of the disease.3 Unlike ALL, the incidence of AML is relatively constant throughout childhood and in general has a poorer prognosis, with approximately 60% of patients surviving at 5 years from diagnosis.4
The signs and symptoms of acute leukemia reflect replacement of bone marrow or result from extramedullary collections of leukemic blasts. Common presentations include pallor, fatigue, petechiae, purpura, and infection as a result of defective hematopoiesis from marrow replacement. Lymphadenopathy, hepatomegaly, splenomegaly, and mediastinal or testicular masses may represent extramedullary involvement. Bone pain may result from leukemic involvement of the periosteum and bone, causing patients to limp or even refuse to walk. Leukemia may be present in the CNS, leading to cranial nerve deficits, headache, or changes ...