A clinicopathological and molecular analysis of cervical carcinomas with basaloid features.

ABSTRACT

AIMS: To investigate the relationship between adenoid basal carcinoma (ABC), adenoid cystic carcinoma (ACC) and squamous cell carcinoma (SCC) in the uterine cervix. METHODS AND RESULTS: We analysed the clinicopathological and molecular features in two pure ABCs, 15 SCCs with ABC-/ACC-like features and seven basaloid SCCs (BSCCs) by chart review, immunohistochemistry, human papillomavirus (HPV) RNA in-situ hybridisation and fluorescence in-situ hybridisation. All patients were alive with no evidence of disease, except for one patient with ACC-like features who died of disease at 18 months post diagnosis. The mixed carcinomas comprised variable SCCs and ABC-/ACC-like components displaying vague transitional zones. All components consistently showed diffuse p16, p63 and SOX2, variable cytokeratin (CK)7 and CK17 and rare Ber-EP4 and MYB expression; there was a substantially lower Ki67 index in pure ABCs and the ABC-like components. The ACC-like components showed no myoepithelial differentiation (SMA, calponin and S100) and MYB gene fusions. CK7, CK17 and Ber-EP4 were characteristically stronger in BSCCs than in the mixed carcinomas (P < 0.01). High-risk HPV (HR-HPV) E6/E7 mRNA was detected in 12 mixed carcinomas and seven BSCCs, but not in pure ABCs. The HR-HPV mRNA expression was higher in the SCC components and BSCCs than in the ABC-like components of mixed carcinomas (P < 0.05). CONCLUSIONS: The ACC-like components in mixed carcinomas probably represent the morphological mimics of salivary ACCs. ABC-like components may be the potential precursor of the ACC-like and SCC components. HR-HPV oncogenes may play a role in the pathogenesis of SCCs with ABC-/ACC-like features.