A case is presented of primary Sjögren's syndrome of the parotid gland with specific skin manifestations, consisting of diffuse lymphoid infiltrates with proliferative and metaplastic changes of sweat glands, a histologic picture similar to that seen in the parotid gland. Material of the parotid gland, a submandibular lymph node showing expanded T-cell areas, and several skin biopsies were studied immunohistologically for the presence of clonal B-cell populations. Because of a polyclonal kappa/lambda pattern of the B-lymphocytes, the possibility of a B-cell non-Hodgkin's lymphoma (NHL) was excluded. The initially morphologically benign lymphocytic skin infiltrates (1985) changed into a pleomorphic T-cell lymphoma (1987). Southern blot analysis of the atypical skin infiltrates and of the original material of the parotid gland and submandibular lymph node revealed identical clonal rearrangements of the T-cell receptor B-chain. Rearrangement of Ig genes was not found.