Clinicopathological comparison and assessment of Ki67, p53 and c-myc immunoexpression in carcinoma cuniculatum, verrucous carcinoma and microinvasive squamous cell carcinoma of the oral cavity

Abstract

ObjectiveTo illustrate the clinicopathological comparison of carcinoma cuniculatum (CC), verrucous carcinoma (VC) and microinvasive squamous cell carcinoma (MISCC) and to compare the immunoexpression Ki67, p53 & c-myc in these entites. Material and methodsClinical and histopathological parameters observed in total 67 cases (12 cases of CC, 22 cases of VC and 27 cases of MISCC). Ki67 & p53 labelling index and c-myc immunoexpression (localization of stain (1: cytoplasmic; 2: nuclear; 3: both), intensity of stain (1: mild; 2: moderate; 3: strong) and distribution of stain in epithelium (1: basal third; 2: up to middle third; 3: up to upper third; 4: invasive islands)). ResultsCC predominantly showed keratin filled crypts, keratin microabscess, microsequestra formation and lymphocytic exocytosis. VC showed broad pushing invasive front, parakeratin plugging along with verrucous projections. Irregular infiltrating rete ridge pattern and severe cytological atypia were findings of MISCC. Ki67 LI was 12.70 % in CC, 23.34 % in VC and 28.27 % in MISCC. p53 LI was 44.167 % in CC, 30.18 % in VC and 29.51 % in MISCC. Ki67 LI showed statistically significance difference between CC and MISCC. Moderate to strong cytoplasmic immunoexpression was found in epithelium as well as in invasive islands of MISCC compared to CC and VC. ConclusionCC shows endophytic epithelium proliferation with mild to moderate dysplasia and no definite invasive front in contrast to VC. High p53 in CC basal cells correlate with more endophytic epithelial proliferation. Significant high Ki67 LI in invasive islands of MISCC supports its aggressive nature. p53, Ki67 and c-myc panel may be helpful as an adjunct in difficult cases with poorly oriented specimens.