부산대학교 도서관

BACKGROUND: A recent small series demonstrated perfect sensitivity and specificity utilizing immunostaining for PHLDA1, a marker of follicular stem cells, in the distinction of desmoplastic trichoepithelioma and morphoeiform basal cell carcinoma (BCC) in small biopsy specimens. OBJECTIVES: To assess this result more broadly. METHODS: We performed immunoperoxidase staining of BCCs (superficial n = 16, nodular n = 15, micronodular n = 15, infiltrative n = 17, morphoeiform n = 16, infundibulocystic n = 14) and trichoepitheliomas (conventional n = 19, desmoplastic n = 16) with PHLDA1. RESULTS: Morphoeiform BCCs typically lacked PHLDA1 staining (88% demonstrated no staining and 12% of cases had staining in < 25% of the tumour), while in contrast 74% of classical and 88% of desmoplastic trichoepitheliomas demonstrated strong PHLDA1 staining in over half of the tumour. However, micronodular BCCs demonstrated focal to diffuse positive staining in a third of the cases. CONCLUSIONS: Based upon our staining results, we discuss the biological significance of PHLDA1 expression and the limits in its diagnostic utility.