Abstract

Background: Oral Squamous Cell Carcinoma (OSCC) cancer arises due genetic and epigenetic changes caused by added infliction of various carcinogens including alcohol, smoking, tobacco, chronic injury. Patients treated with primary OSCC are more prone to develop multiple premalignant and malignant lesions in aero digestive tract compared to healthy individuals, due to existing field defects. Our study was conducted to histopathologically evaluate the apparently normal looking mirror image mucosa from contralateral anatomic site in unilateral, single, untreated and histopathologically diagnosed oral cancer patients to detect the incidence of premalignant and malignant lesions.

Methods: A cross-sectional observational study was carried out in Oral and Maxillofacial Surgery Department, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. About 44 consecutive eligible patients aged between 28 to 76 years diagnosed with primary, solitary, unilateral and untreated OSCC were subjected to mirror image biopsy and histopathologic examination from corresponding contralateral intraoral anatomic locations.

Results: Among 44 patients, 16 patients displayed dysplasia in oral mucosa at mirror image site, among which 12 had mild dysplasia and 4 had moderate dysplasia. Dysplasia was found higher in patients with pan with betel nut chewers plus tobacco chewers followed by paan with betel nut chewers and smokers. It was observed that buccal mucosa and gingivobuccal sulcus displayed more premalignant changes.

Conclusion: This study has demonstrated that clinically normal-looking mucosa from oral cancer patient’s exhibit premalignant dysplastic changes in significant proportions. Hence, the mirror image biopsy would be an important diagnostic tool for early detection dysplastic changes in apparently normal mucosa preconditioned with field effect, to prevent further progression to cancer.

Keywords: Field cancerization; Metachronous tumors; Erythroleukoplakia; Primary cancer; Aerodigestive tract