Immunohistochemical characterization of non-epithelial cells in spiradenoma.

Spiradenoma is unique with respect to the presence of a large number of non-epithelial cells, including S100 protein(+) cells, most of which are presumably Langerhans cells, in the parenchyma as shown in the published work. However, the characterization of these non-epithelial cells to date is insufficient. Immunohistochemistry of CD1a, CD3, CD4, CD8, CD56, CD68, intercellular adhesion molecule-1 (ICAM-1), and HLA-DR, as well as double-immunofluorescence labeling of S100 protein/CD1a and CD1a/CD3, was performed using paraffin-embedded specimens from five cases of spiradenoma retrospectively. Non-epithelial cells evenly distributed throughout the parenchyma of spiradenoma primarily consisted of CD1a(+) Langerhans cells and CD3(+) T cells. ICAM-1 was expressed by epithelial cells and non-epithelial cells in the parenchyma. HLA-DR on the epithelial cells was limited to the focal area. In double-immunofluorescence labeling, approximately one-half of Langerhans cells were spatially related to T cells in the parenchyma, suggesting their functional interaction.

Erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis: frozen-section diagnosis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) may be fatal. Although classified by body surface area skin detachment, initial stages of both may present with erythema multiforme (EM)-like lesions. To diagnose and predict disease activity adequately as early as possible for patients revealing EM-like lesions, we performed frozen-section diagnosis. Thirty-five patients clinically diagnosed as EM, SJS or TEN were biopsied to diagnose and predict disease progression within the initial-visit day. Half of a histological section taken from a lesion was snap-frozen and immediately cryostat-sectioned, acetone-fixed and stained with hematoxylin-eosin. Specimens were examined with light microscopy for presence of epidermal necrosis. A section from unaffected sites was also examined for 11 patients. Specimens were examined with light microscopy for presence of graft-versus-host reaction (GVHR)-like findings: apoptotic keratinocytes and satellite cell necrosis. Epidermal necrosis was seen in nine patients. Initial diagnosis of the nine was one of overlap SJS-TEN, four of SJS and four of EM, and final diagnosis of those was one of TEN, one of overlap SJS-TEN, four of SJS and three of EM. Dissociation between initial and final diagnosis was seen in three cases. GVHR-like findings in the epidermis were observed in two patients finally diagnosed as overlap SJS-TEN and TEN. Frozen sections are useful not only to make a diagnosis of erythema multiforme but to assess a potential to exhibit more aggressive clinical behaviors (SJS or TEN).