METHODS: This study was conducted on 83 cases of known OSCCs and OPMDs (oral submucous fibrosis, leukoplakia, and oral lichen planus). Assays, such as polymerized chain reaction (PCR) and reverse transcription-PCR, were carried out for HPV and p16 . The results were compared with clinical information and with the literature. The results were analyzed using SPSS 16.0 for windows.
RESULTS: P16 expression was mostly seen in males than in female patients. Out of 21 cases of keratosis with dysplasia, 19% expressed p16 . Of 26 oral lichen planus patients, 29% showed the p16 gene with immunohistochemistry. Interestingly, a high percentage of OSF cases expressed p16 (48.27%). Minimal expression was observed in OSCC (6.25%). HPV DNA was detected in 2.4% of the total sample. Both p16 and HPV were detected in a single case of OSCC. OPMDs expressed a significant amount of the p16 gene by immunohistochemistry and reverse transcription-PCR technique when compared with malignant lesions, suggesting a possible inactivation of the p16 gene. HPV and p16 are mostly negative in our OSCC sample, exhibiting low prevalence.
CONCLUSIONS: OPMDs expressed a significant amount of the p16 gene when compared with malignant lesions, suggesting a possible inactivation of the p16 gene. Although OSF expressed p16 , HPV was not detected, suggesting that over-expression could be independent of HPV. OSCC shows low HPV prevalence.
OBJECTIVES: To design and perform a simple surveillance on OLP patients based on colour-coded topography mouth maps (TMM).
MATERIALS AND METHODS: Three colour-coded TMM were employed: red for OLP in high risk oral mucosal sites, yellow for cases showing improvement and green for asymptomatic lesions at each recall visit. In this preliminary study, these were applied on 30 histologically confirmed OLP individuals attending the Oral Medicine Clinic at the Department of Oral Pathology, Oral Medicine and Periodontology, Faculty of Dentistry, University of Malaya. The sites and extent of OLP lesions were charted on either red, yellow or green TMM based on defined criteria. This surveillance evaluated OLP in relation to patientandapos;s age, race, gender, underlying systemic conditions, oral habits, initial onset of OLP, oral manifestations and presence/absence of clinically suspicious areas.
RESULTS: Study sample comprised 4 (13.3%) Malays, 9 (30.0%) Chinese and 17 (56.7%) Indians. Most OLP patients belong to the green TMM (n= 14, 46.6%) group followed by red (n= 11, 36.7%) and yellow (n= 5, 16.7%) groups. Of the 11 cases with red TMM, rebiopsy was performed on 4 cases but no dysplasia was detected. Any local confounding factors namely periodontal disease or faulty dental restorations were managed accordingly.
CONCLUSIONS: TMM is simple to use and aided the clinicians in terms of time saving and patient management. Hence, follow-up of OLP patients can be carried out more efficiently and appropriately. TMM can be used for surveillance of other oral precancerous lesions and conditions.