Fascin expression in cervical normal squamous epithelium, cervical intraepithelial neoplasia, and superficially invasive (stage IA1) squamous carcinoma of the cervix

The aims of this study were to: investigate fascin expression in normal cervix, cervical intraepithelial neoplasia (CIN), and stage IA1 squamous cell carcinoma (SCC). Fascin immunostaining was performed in cervical biopsies showing normal squamous epithelium (n=10), CIN 1 (n=10), CIN 2-3 without invasion (n=11), and CIN 2-3 adjacent to SCC (n=40); SCC was also present in 27 of the latter cases. Fascin expression in normal squamous epithelium was restricted to basal and parabasal cells, whereas there was increased staining in immature squamous metaplasia and in most CIN lesions. Full thickness staining was more frequent in high grade CIN adjacent to invasion than in CIN 2-3 alone. Eighteen SCCs (67%) were fascin positive and seven cases showed accentuated staining at the tumour-stromal interface (invasive front). There was no consistent relationship between fascin expression in CIN lesions and in corresponding carcinomas. Fascin staining in reactive stromal cells sometimes made identification of the invasive neoplastic cells difficult. Fascin is overexpressed in most CIN lesions and this may be a marker of increased invasive potential in high grade CIN. However, fascin staining does not distinguish low and high grade CIN or in situ and invasive squamous neoplasia. Therefore fascin has limited diagnostic utility in demonstrating superficial stromal invasion. Copyright © 2014 Royal College of pathologists of Australasia.