Percentage of {Gamma}{Delta} T Cells in Panniculitis by Paraffin Immunohistochemical Analysis.

Cutaneous T-cell lymphomas with panniculitis-like histologic features have different clinical courses depending on whether they are composed of alphabeta T cells or gammadelta T cells, necessitating their distinction for proper prognostication. However, unlike alphabeta T cells, gammadelta T cells cannot be reliably detected in formalin-fixed, paraffin-embedded sections. We demonstrated that a commercially available antibody can detect gammadelta T cells and examined 2 cases of flow cytometry-proven gammadelta T-cell lymphomas and 15 control cases of nonneoplastic panniculitis. In both lymphomas, the atypical lymphocytes were gammadelta T cells, whereas the reactive lymphocytes were alphabeta T cells. In contrast, nonneoplastic panniculitis had predominantly alphabeta T cells with many fewer and individually scattered gammadelta T cells. The detection of gammadelta T cells in paraffin sections provides a powerful new tool to characterize T cells in lymphomas and inflammation

Lupus erythematosus induced by medications, ultraviolet radiation, and other exogenous agents: a review, with special focus on the development of subacute cutaneous lupus erythematosus in a genetically predisposed individual.

Exogenous agents implicated in or suspected of precipitating subacute cutaneous lupus erythematosus (SCLE) and lupus erythematosus (LE) are reviewed. An illustrative case of environmentally induced SCLE is presented. A previously healthy 30-year male homozygous for the tumor necrosis factor-alpha (TNF-alpha) 308. A promoter allele developed SCLE after spending several hours removing fertilizer- and pesticide-containing hay from an agricultural barn in the springtime. The cutaneous eruption soon resolved, only to reappear 3 weeks later on the day the patient re-entered the barn. An environmental agent present in the barn, coupled with springtime ultraviolet light, likely triggered the disease in this immunogenetically susceptible individual

Cutaneous metastatic chordoma with concomitant tuberous sclerosis.

BACKGROUND: Chordomas are rare malignant tumors of notochord origin and are locally aggressive with a metastatic potential. Of noted interest, the skin rarely is seen as a metastatic site. METHODS AND OBSERVATIONS: We describe a 20-month-old infant whose primary presentation of a clivus-based chordoma was multiple asymptomatic cutaneous nodules. A skin biopsy showed large vacuolated cells embedded in a myxoid stroma. Immunohistochemical staining was positive for S-100, keratin, and epithelial membrane antigen markers consistent with malignant chordoma. Magnetic resonance imaging revealed a clivus-based chordoma with scattered metastases within the neuraxis and multiple visceral sites. Further examination also revealed a diagnosis of tuberous sclerosis. LIMITATIONS: An observed association between chordoma and tuberous sclerosis cannot be established firmly on the basis of a case report. CONCLUSIONS: This case illustrates a diagnostic challenge because of the unusual presentation of an already rare tumor. By reporting our case, we hope to assist in the recognition of this rare dermal condition and highlight the speculated coexistence of tuberous sclerosis with chordoma tumors