A series of 25 cutaneous B-cell lymphoid proliferations was analyzed for the presence of the (14; 18) translocation using the polymerase chain reaction. Junctional sequences of rearranged chromosomes 14 and 18 were amplified in vitro, and t (14; 18) specific sequences were detected in 1 of 14 primary cutaneous B-cell lymphomas, in 3 of 8 primary nodal B-cell lymphomas and in none of 3 B-cell pseudolymphomas. These results indicate that the t (14; 18) may occur in a small subset of primary cutaneous lymphoma. However, the difference in incidence of the t (14; 18) between primary nodal and primary cutaneous lymphomas suggests that different molecular mechanisms are involved in the pathogenesis of these lymphomas.