Recognition of common childhood malignancies.

Although cancer has an annual incidence of only about 150 new cases per 1 million U.S. children, it is the second leading cause of childhood deaths. Early detection and prompt therapy have the potential to reduce mortality. Leukemias, lymphomas and central nervous system tumors account for more than one half of new cancer cases in children. Early in the disease, leukemia may cause nonspecific symptoms similar to those of a viral infection. Leukemia should be suspected if persistent vague symptoms are accompanied by evidence of abnormal bleeding, bone pain, lymphadenopathy or hepatosplenomegaly. The presenting symptoms of a brain tumor may include elevated intracranial pressure, nerve abnormalities and seizures. A spinal tumor often presents with signs and symptoms of spinal cord compression. In children, lymphoma may present as one or more painless masses, often in the neck, accompanied by signs and symptoms resulting from local compression, as well as signs and symptoms of systemic disturbances, such as fever and weight loss. A neuroblastoma may arise from sympathetic nervous tissue anywhere in the body, but this tumor most often develops in the abdomen. The presentation depends on the local effects of the solid tumor and any metastases. An abdominal mass in a child may also be due to Wilms' tumor. This neoplasm may present with renal signs and symptoms, such as hypertension, hematuria and abdominal pain. A tumor of the musculoskeletal system is often first detected when trauma appears to cause pain and dysfunction out of proportion to the injury. Primary care physicians should be alert for possible presenting signs and symptoms of childhood malignancy, particularly in patients with Down syndrome or other congenital and familial conditions associated with an increased risk of cancer.