RESUMO
To extend flow cytometry (FC) to the diagnosis of nonhematopoietic neoplasms, we have developed new flow cytometric assays to identify expression of cytokeratin, epithelial cell adhesion molecule (EpCAM)/epithelial glycoprotein-2, myogenin, and CD99. To validate these assays, we correlated the flow cytometric results with the histologic and immunohistochemical results on paraffin-embedded tissue in a series of 21 cases, including 17 carcinomas, 1 atypical carcinoid, 2 rhabdomyosarcomas, and 1 Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET). Six of 7 assayed carcinomas and the carcinoid were positive for cytoplasmic cytokeratin by the flow cytometric assay. EpCAM was expressed by 11 of 12 carcinomas that were assayed by FC. Both rhabdomyosarcomas expressed myogenin by FC, and the ES/PNET case expressed CD99. Interestingly, the blast-associated antigen CD90 was expressed uniformly on the ES/PNET case and on subsets of cells in the rhabdomyosarcoma and carcinoma cases. Potential applications of the flow cytometric assay to nonhematopoietic neoplasms will include evaluating samples with limited material, monitoring disease persistence and recurrence in patients with previous diagnoses, and making rapid diagnoses in urgent cases.
Assuntos
Linhagem da Célula , Citometria de Fluxo , Neoplasias/patologia , Antígeno 12E7 , Antígenos CD/análise , Antígenos de Neoplasias/análise , Carcinoma/patologia , Moléculas de Adesão Celular/análise , Molécula de Adesão da Célula Epitelial , Estudos de Viabilidade , Imuno-Histoquímica , Imunofenotipagem , Queratinas/análise , Antígenos Comuns de Leucócito , Miogenina/análise , Rabdomiossarcoma/patologia , Antígenos Thy-1RESUMO
The coexistence of 2 types of malignant neoplasms is relatively uncommon. We report a pigmented melanocytic lesion occurring adjacent to a previously treated basal cell carcinoma. Histology showed melanoma (lentigo maligna type) colonizing basal cell carcinoma demonstrated by hematoxylin-eosin and immunocytochemistry stains. It is unclear whether this lesion has the metastatic potential of an invasive melanoma of similar thickness, or simply reflects melanoma in situ extending into an epidermal-derived tumor analogous to appendageal extension of lentigo maligna. We review the literature on melanoma colliding with basal cell carcinoma. Therapeutic and prognostic problems are posed by this unique situation.
