Verrucous Carcinoma, A Very Well Differentiated Form of OSCC? - An Immunochemical Exploratory Study

Introduction: Verrucous carcinoma shows an analogous biological behaviour to well-differentiated Oral Squamous Cell Carcinoma (OSCC). So, it is a difficult task to differentiate the above two entities based on clinical and pathological behaviour. Immunohistochemical studies can help in investigating the differences between the biological behaviours of these carcinomas. Laminin may be used as a status indicator of intact or degraded basement membrane during tumorigenesis. Thus, the present study aimed to assess the immunohistochemical expression of laminin in different grades histological grades of OSCC and VC. Methods: Laminin expression was evaluated in 31 biopsy-proven cases of Oral Squamous Cell Carcinoma (OSCC) and 10 cases of Verrucous Carcinoma (VC). Results: We observed that most cases of VC (90%) were negative or mildly stained for cytoplasmic laminin while the majority of cases of OSCC (74.2%) stained moderately for the same. Further, VC cases showed a total absence of linear laminin staining around the tumour-host interface in contrast to 13% of OSCC cases that were correspondingly stained (p<0.001). Conclusion: The present study, therefore concludes that the interface expression in Verrucous Carcinoma distinctly differed from that in well-differentiated Oral Squamous Cell Carcinoma. Cytoplasmic laminin expression increased and interface staining decreased with unfavourable clinicopathological outcomes thereby rendering laminin an expedient marker in evaluating the histological differentiation and aggressiveness of oral carcinoma