Expression of stem-cell markers (cytokeratin 15 and nestin) in primary adnexal neoplasms-clues to etiopathogenesis.
BACKGROUND
The overlap in histopathologic features and immunoprofile of eccrine and apocrine neoplasms confounds basic issues relating to lineage of these entities.


METHODS
We evaluated expression of follicular stem-cell markers, cytokeratin (CK) 15 and nestin, in 78 benign and 23 malignant adnexal neoplasms.


RESULTS
CK15 and nestin expression were noted in 39 of 78 (50%) and 36 of 78 (46%) cases in the benign group, respectively (8 cutaneous mixed tumor, 10 hidradenoma papilliferum, 9 apocrine cystadenoma, 11 cylindroma and/or spiradenoma, and 9 poroma/dermal duct tumor). CK15 and nestin expression were noted in 11 of 23 (48%) and 7 of 23 (30%) cases in the malignant group, respectively (6 microcystic adnexal carcinoma, 7 porocarcinoma, and 9 eccrine carcinoma). Except 1, both markers were negative in 4 syringocystadenoma papilliferum, 10 hidradenoma, 1 syringofibroadenoma, 10 syringoma, 1 eccrine adenoma, 8 poroma/dermal duct tumor, 5 eccrine hidrocystoma, and 1 apocrine carcinoma.


CONCLUSIONS
Given that follicular germinative cells give rise to the folliculosebaceous apocrine unit, expression of CK15 and nestin in the majority of cutaneous mixed tumor, hidradenoma papilliferum, apocrine cystadenoma, and cylindroma/spiradenoma is suggestive of an apocrine origin/differentiation of these neoplasms. Reinforcing this and a novel finding of our study is the preferential expression of nestin in myoepithelial cells of these lesions.
Mahalingam
Meera
M
Department of Dermatology, Boston University School of Medicine, MA, USA.
Srivastava
Anvita
A
Hoang
Mai P
MP
D001050:Apocrine Glands / Q000737:chemistry* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D001900:Boston; D019070:Cell Lineage; D003937:Diagnosis, Differential; D004439:Eccrine Glands / Q000737:chemistry* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000032:analysis*; D053569:Keratin-15 / Q000032:analysis*; D018294:Neoplasms, Adnexal and Skin Appendage / Q000737:chemistry* / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000737:chemistry* / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000032:analysis*; D064231:Nestin; D011237:Predictive Value of Tests; D013544:Sweat Gland Neoplasms / Q000737:chemistry* / Q000473:pathology
D014408:Biomarkers, Tumor; D007381:Intermediate Filament Proteins; C116015:KRT15 protein, human; D053569:Keratin-15; C577484:NES protein, human; D009419:Nerve Tissue Proteins; D064231:Nestin