Jornal de Biomarcadores Moleculares e Diagnóstico

Comparative Immunohistochemical Study of P63, SMA, CD10 and Calponin in Distinguishing In Situ from Invasive Breast Carcinoma

Abstract

Dina M Abdallah, and Nevine MF El Deeb

Background: Loss of the outer myoepithelial layer is the hallmark of invasive carcinoma, and demonstration of this loss can be documented by immunohistochemical techniques. The purpose of this study was to compare the specificity and sensitivity of four of the most commonly used-markers of myoepithelial cells: P63, SMA, CD10 and Calponin in distinguishing in situ from invasive breast carcinoma.

Material and methods: Immunostaining using antibodies against P63, SMA, CD10 and Calponin was performed on representative paraffin sections from 40 cases of breast masses examined at the Department of Pathology, Alexandria Faculty of Medicine, and diagnosed as ductal carcinoma in situ ± an invasive ductal or lobular carcinoma.

Results: Calponin yielded a slightly higher sensitivity than each of P63, CD10 and SMA (65% vs 54%, 19% and 17%, respectively). The results of both semiquantitative assessment and computerized image analysis of immunohistochemically-stained sections were statistically correlated, statistically p63 showed the highest specificity for myoepithelium and the least expression in non-myoepithelial layer of all antibodies tested. In contrast, SMA showed the least specificity and highest non-myoepithelial expression especially in stromal myofibroblasts and in vascular smooth muscle cells.

Conclusions: Calponin and P63 are more sensitive myoepithelial markers as compared to CD10 and SMA; with Calponin slightly more sensitive than P63. SMA should not be used alone as a myoepithelial marker due to its low specificity.