Warthin's tumor: a functional immunologic study of the lymphoid cell component.

The origin and nature of the lymphoid cell component of Warthin's tumor are controversial. The present report describes the application of immunologic functional testing to the study of Warthin's tumor lymphocytes. Numbers of B and T cells are comparable to those of other lymph nodes. A vigorous stimulatory response to phytohemagglutinin reflects the predominance of functional T cells. These findings, in conjunction with morphologic observations, support the concept that the lymphoid component of Warthin's tumor is derived from a pre-existing lymph node.