Carlos H. Nousari

Multicentric plasma cell variant of Castleman's disease with cutaneous involvement

Background:  Castlemans disease (CD) is a rare low‐grade B‐cell lymphoproliferative disorder that can be associated with a variety of antibody‐mediated paraneoplastic syndromes. The disease is classified clinically by two forms and three histologic variants.

Mucosal "peeling" biopsy technique for the immunopathologic evaluation of desquamative gingivitis-associated mucous membrane pemphigoid.

D ESQUAMATIVE GINGIVITIS CAN RESULT from various pathogenetic factors, including mucous membrane pemphigoid (MMP). Adequate gingival sampling for immunopathologic evaluation is mandatory for the diagnosis of MMP. The gingival mucosal “peeling” biopsy technique (Figure 1) yields sufficient epithelium samples for histologic analysis and direct immunofluorescence (DIF). Hemidesmosomal proteins (BPAG1-2 and 6 4-integrin) are the most common MMP autoantigens, resulting in a “capping hemidesmosomal” linear IgG DIF pattern on the gingival epithelial undersurface (Figure 2). To circumvent false-negative DIF results, related to less common, deeper basement membrane zone autoantigens (laminin5/6 and collagenVII), serologic evaluation for anti–basement membrane zone autoantibodies (eg, indirect immunofluorescence and enzyme-linked immunosorbent assay) should be performed. If the findings of DIF and serologic studies are nondiagnostic and a high index of clinical suspicion for MMP remains, an appropriate mucosal punch or incisional biopsy should be performed. Gingival lesions in patients with MMP may deter clinicians from performing sampling owing to technical difficulty. Mucosal peeling can provide adequate immunopathologic samples for the diagnosis of desquamative gingivitis– associated MMP.

Basal cell carcinoma-associated paratumoral follicular and epidermal hyperplasia.

Reactive epithelial hyperplasia is a well-known phenomenon which occurs adjacent to certain neoplasms such as cutaneous fibrous histiocytoma, granular cell tumor, Spitz nevus, and melanoma. We report 46 cases of paratumoral follicular and epidermal hyperplasia associated with basal cell carcinoma (BCC). This reactive process associated with BCC has certain characteristic features. It is focal, superficial, and predominantly folliculocentric. It may resemble other tumors such as squamous cell carcinoma and may appear in sections where BCC is absent. The recognition of this entity may help dermatopathologists avoid misdiagnosing this process as a tumor and can suggest further search (section through the block or rebiopsy) when this reactive phenomenon is seen in sections without the associated BCC.

29 – LUPUS ERYTHEMATOSUS AND THE SKIN

The term lupus (Latin for wolf) was used in the medieval period to describe several skin disorders. Some disorders were related to wolflike facies and others to skin lesions resembling wolf bites. These dermatoses included lupus vulgaris , a form of cutaneous tuberculosis; lupus pernio , a nasal form of cutaneous sarcoidosis, and lupus erythematosus (LE), an autoimmune disease.