CD10 expression in trichoepithelioma and basal cell carcinoma.
BACKGROUND
Trichoepithelioma (TE) is a benign neoplasm that shares both clinical and histologic features with basal cell carcinoma (BCC). However, it is important to distinguish these neoplasms. Limited immunohistochemical stains are available to separate these two tumors.


METHODS
CD10 protein immunohistochemistry was performed on paraffin-embedded biopsies of 13 TE and 23 BCC diagnosed by routine microscopy. Cases were analyzed for pattern of CD10 expression by tumor cells and surrounding stroma.


RESULTS
Twelve of 13 (92%) TE showed positive stromal immunoreactivity. Of these, eight cases also demonstrated positivity of the papilla, and two also showed positivity of the basaloid cells. No TE demonstrated epithelial expression alone. On the other hand, expression of CD10 by basaloid cells was identified in 20 (87%) cases of BCC. Stromal positivity was also identified in three cases of BCC. Condensation of CD10-positive stromal cells around basaloid nests was statistically significant in differentiating TE from BCC (p < 0.0001). Conversely, CD10-positive basaloid cells were seen predominantly in BCC (p < 0.0001).


CONCLUSIONS
This study demonstrates a statistically significant difference in CD10 staining pattern between TE and BCC. Thus, CD10 may be a useful adjunct marker in distinguishing these tumors.
Pham
Teresa Tram N
TT
Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA.
Selim
M Angelica
MA
Burchette
James L
JL
Madden
John
J
Turner
John
J
Herman
Christopher
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002280:Basal Cell Carcinoma / Q000378:metabolism* / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D018295:Neoplasms, Basal Cell / Q000378:metabolism* / Q000473:pathology; D015260:Neprilysin / Q000378:metabolism*; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology
D014408:Biomarkers, Tumor; D015260:Neprilysin