IN the last six years an unusual cancer affecting children in Africa (Burkitt, 1958) has come to the attention of the scientific community. This cancer is particularly noteworthy because of its high incidence in African children (the commonest childhood cancer in Africa) and its peculiar geographic distribution on that continent. It is characterized by an unusual anatomic distribution; the jaws being involved in the majority of cases and a nearly universal sparing of the peripheral lymph nodes. The African lymphoma syndrome is significant within the context of the total cancer problem in that the epidemiology is highly suggestive of viral etiology. Support for this concept is given by the age distribution, apparent lack of racial predilection, and geographical distribution which is related to altitude, temperature and humidity (Burkitt, 1962).A study of the prevalence and distribution of the Burkitt lymphoma outside Africa has not yet been reported. Considering the similarity of geographic distribution between the lymphoma in Africa and tropical vector-born viral diseases on that continent, and considering further that for the most part these same vectorborn viral diseases are endemic to the tropical areas of Central America, this area seemed most likely to contain information about the prevalence and distribution of this entity in the Western hemisphere. This study was initiated to gather information about the Burkitt lymphoma on this hemisphere.The present study was conducted in two parts. The first, a safari by dug-out canoe into the tropical jungles of Darien, Panama, searching clinical evidence of the tumor, and the second part, a search through the histopathologic collection at