Lymphoma is the third most common cancer in children in the United States.
Approximately 10 percent of cancers diagnosed in children less than 15 years of age are lymphomas. Symptoms depend on the site and extent of disease. They may consist of a painless unexplained swelling in the head, neck, armpit, groin or abdomen. Cough from a chest mass is possible, as are bone pain and refusal to walk. Abdominal pain and vomiting may bring children with an abdominal lymphoma to medical attention.