No abstract

EBV-associated cutaneous B-cell lymphoma is characterized by a long interval between the initiation of immunosuppression and the development of lymphoma. Although previous reports have reported an indolent clinical course, an aggressive clinical course may occur. HHV8 and lytic phase EBV antigens are detected in some cases, possibly suggesting a pathogenetic role.

Most cutaneous T-cell lymphomas are derived from mature postthymic T cells of the CD4 subtype. When other less common profiles are encountered, a diagnostic challenge is posed. Accurate categorization is critical because of the specificity of therapeutic regimens, including biologics. A 65-year-old woman was seen in 2001 because of a thigh mass manifesting an unusual phenotype eventually categorized as a mature postthymic CD8+ T-cell lymphoma with CD10 and weak CD20 expression. Molecular studies revealed T-cell receptor and heavy chain immunoglobulin rearrangement. Her cutaneous disease progressed despite several cycles of chemotherapy and radiation therapy. However, a therapeutic trial with denileukin diftitox resulted in a striking response. The importance of this case lies in the novel phenotype and dual T- and B-cell rearrangements. Rather than representing an aberrant phenotype, this tumor may represent the malignant counterpart of a benign population of weakly CD20+ T cells of the CD8 subset.

Dermatomyositis, a connective tissue disease syndrome where antibodies to the endothelium of the microvasculature of the skin, muscle and lung are implicated in lesional propagation, is characterized by photodistributed erythema, heliotrope rash, Gottron's papules, muscle weakness and interstitial pulmonary fibrosis. Endotheliotropic viruses and underlying neoplasia are among the inciting triggers. Uncommon drugs, namely the lipid-lowering agents, have been implicated in dermatomyositis. The patient, a 57-year-old man, developed a photodistributed rash and muscle weakness following treatment with the antifungal medication, terbinafine. A skin biopsy was performed, showing an atrophying interface dermatitis with pandermal mucinosis and striking vasculopathic changes including endothelial cell necrosis with denudement and basement membrane zone reduplication. Ultrastructural studies confirmed the presence of endothelial cell injury. Direct immunofluorescent testing showed prominent staining of C5b-9 along the dermal-epidermal junction and within the vasculature. Western blot studies showed strong seroreactivity of his serum to an endothelial-based protein weighing 45,000, a common target described in other microvascular injury-based syndromes. We have shown a temporal association between use of terbinafine and the development of dermatomyositis. The exact basis remains speculative. One potential hypothesis is based on the fact that terbinafine, the active agent in terbinafine, triggers apoptosis of human endothelial cells in culture. Enhanced endothelial cell apoptosis results in the displacement of various cellular antigens creating a state of neoantigenicity; its attendant sequelae is held to be one of anti-endothelial cell antibody formation, a defining pathogenetic event in the evolution of dermatomyositis. The second may be because of the effects of the drug on the promotion of an interferon-rich T-helper-1-dominant cytokine milieu.

This case identifies a cutaneous presentation of subclinical B-CLL. There are two prior reports describing B-CLL presenting initially in the skin. In one case, the infiltrates were incidental on a re-excision specimen. The second report suggests 16% of B-CLL patients have cutaneous manifestations as the first sign of disease.