DiGeorge syndrome associated with multiple squamous cell carcinomas.

Experimental evidence and clinical experiences have have shown that immune mechanisms and cancer are closely related. A case of a 42-year-old man with DiGeorge syndrome is presented as an interesting example of an impaired immune mechanism and is described in association with multiple squamous cell carcinomas of the upper respiratory system. The congenital absence of the thymus gland in DiGeorge syndrome results in an absence of a cell-mediated immune response. There are plasma cells and germinal centers in lymph nodes, but lymphocytes in the paracortical areas are sparse. Patients wiith DiGeorge syndrome have no delayed hypersensitivity, cannot be actively sensitized with dinitrochlorobenzene, reject allografts poorly, and have no lymphocytic response to phytohemagglutinin antigens.