Reliability of Incision Biopsy for Diagnosis of Oral Verrucous Carcinoma: A Multivariate Clinicopathological Study.

INTRODUCTION: Studies have reported 20 % of conventional squamous cell carcinoma in patients with verrucous carcinoma (VC), later these cancers were termed as hybrid VC. It is important to distinguish both while planning treatment since hybrid VC requires addressing regional lymphatics in addition to respective surgery. Information on odds of missing the foci of invasion on routine incision biopsy might be useful in this regard.

PATIENTS AND METHODS: Records of all the patients surgically treated for oral cancer from Jan 2010 to Oct 2013 in a Tertiary Cancer Centre was analyzed. Patients diagnosed with primary VC or Verrucous Hyperplasia on incision biopsy were included in the study. Proportion of patients undiagnosed for invasive component on incision biopsy was calculated, multivariate analysis of the sample was performed to find associated cofounders.

RESULTS: Fifty-five patients who reported with the diagnosis of VC (n = 53) or Verrucous Hyperplasia (n = 2) on incision biopsy were included in the study. Twenty-seven were diagnosed as VC and 28 as hybrid VC after excision. This corresponded to 51 % (n = 28) of cases missing invasive component on incision biopsy. VC was significantly more commonly seen in lip and in buccal mucosa, hybrid VC was more commonly seen in tongue and gingiva and this association was statistically significant (p = 0.031) in our study.

CONCLUSION: Incision biopsy is extremely unreliable to diagnose and differentiate oral Hybrid VC from VC or Verrucous Hyperplasia. Caution is required while planning treatment of these patients regarding possibility of presence of conventional squamous cell carcinoma within these tumors.