Cutaneous lymphoid proliferations: a clinicopathological continuum?

Abstract 

The distinction of cutaneous lymphomas from inflammatory dermatoses is considered to be one of the most vexing problems in diagnostic dermatopathology. Identification of “clonal dermatoses” which, in some instances, evolve into overt lymphomas, has prompted the suggestion that cutaneous lymphoid hyperplasia may represent a continuum with lymphomatous potential. Some of the difficulties that we encounter in the diagnosis of cutaneous lymphomas are, however, conceptual. That is because diagnostic criteria for the earliest stages of malignant tumours impinge on the “grey zone” between what is clearly benign and what is obviously malignant. On the other hand, a pragmatic approach to the management of patients with “borderline” lymphoproliferative disorders seems to be the most appropriate. Dermatologists and dermatopathologists should be mindful of patients’ best interests, avoiding unnecessarily aggressive treatment of cutaneous lymphoid infiltrates. That approach is valid regardless of personal opinion over whether such lesions are “premalignant” or “early malignant”.

Keywords: clonal dermatitis, cutaneous B-cell lymphoma, cutaneous T-cell lymphoma, lupus erythematosus panniculitis, lymphomatoid papulosis, mycosis fungoides, pseudolymphoma, small plaque parapsoriasis, subcutaneous ‘panniculitis-like’ T-cell lymphoma