A two-year-old girl presented with a 3-month history of generalized pruritus. One week before hospitalization she developed a superior vena cava syndrome and obstruction of the upper airways. Clinical and laboratory findings included generalized lymphadenopathy, a mediastinal mass compressing the tracheal lumen to the point of near closure, hepatomegaly and moderate eosinophilia. The diagnosis of an anaplastic large cell lymphoma (ALCL) was made by the histologic examination of a mediastinal lymph node. The history of generalized pruritus without diagnostic skin lesions was as uncommon as age at presentation. In conclusion, this case illustrates that generalized pruritus in a toddler can be an early sign of ALCL.