The cutaneous manifestations of paraproteinaemia. I

Primary cutaneous B‐cell lymphomas: then and now

“…Several authors were even reluctant to recognize the existence of pCBCL: Isaacson and Norton 1 remarked in their excellent book on ‘Extranodal lymphomas’ that ‘… low‐grade B‐cell lymphomas are an extremely rare group …’ or that ‘primary follicular lymphoma of the skin is extremely uncommon, if it occurs at all’. For Russel Jones, 2 ‘… lymphoproliferative disorders involving the B‐cell series are characterized by the absence of cutaneous involvement’, and Edelson 3 in a discussion of cutaneous lymphomas writes that ‘… application of the principles of cellular immunology to their study has shown them to be almost invariably T‐cell neoplasms’. Current evidence indicates that pCBCL represent about 25% of all cutaneous lymphomas 4,5 …”

Cutaneous manifestations of paraproteinaemia. Part II

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In the first part of this review (Russell Jones, 1980), the associations between paraproteinaemia and cutaneous disorders were classified on a pathogenetic basis into five groups: specific infiltrates (Group I), light chain deposition (Group II), quantitative effects of paraprotein production (group III), immunological effects of paraprotein production (group IV) and associations of indeterminate aetiology (group V). Vasculitis and related processes which depend upon the complement-fixing ability of paraproteins, were included in group IV, and a distinction was made between paraproteins which activate complement directly and paraproteins with antibody activity in which complement activation results from immune complex formation.

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