The role of Ki‑67, p16, CD34, Bcl‑2, cyclooxygenase‑2 in the pathogenesis of proliferative verrucous leukoplakia.

CONTEXT: Proliferative verrucous leukoplakia (PVL) is a highly persistent and aggressive oral pre‑malignant lesion with an obscure etiopathogenesis and a malignant transformation rate of 85‑100%. AIMS: The aim of the present study is to assess the role of Ki‑67, p16, CD34, Bcl‑2, cyclooxygenase‑2 (COX‑2) in the spectrum of PVL to ascertain their role in its etiopathogenesis. SETTINGS AND DESIGN: A retrospective chart analysis was carried out on a series of seven confirmed cases of PVL, which were followed‑up for 2 years. SUBJECTS AND METHODS: Immunohistochemical appraisal of these cases was carried out by a panel of markers, related to cell proliferation, cell cycle regulation, angiogenesis, apoptosis and inflammation. The expression of these markers was correlated with patients’ clinicopathological profile. STATISTICAL ANALYSIS USED: The frequency distribution of the group data was analyzed. RESULTS: The latest labeling index of Ki‑67 in our cases ranged from 8.18 to 12.6. p16 was positive in 3/7 cases. Bcl‑2 expression was moderately positive in 2/7 cases. All cases were intensely positive for COX‑2 staining. Microvascular density assessed by CD34 staining ranged from 11 to 20/high power fields. One case which transformed into squamous cell carcinoma demonstrated increased Ki‑67, Bcl‑2, COX‑2, CD34 expression, but negative p16 and Bcl‑2 expression. CONCLUSIONS: Application of these markers in understanding the behavior of PVL suggests that an imbalance between the proliferation apoptosis dynamics of the lesion accompanied by an increase in inflammation and angiogenesis underlie the molecular pathogenesis of the PVL spectrum.

Molecular analysis of oral squamous cell carcinoma: A tissue microarray study.

Background : An intriguing aspect of Oral Squamous Cell Carcinomas (OSCC) is its behavioral disparity. Among patients who present with the similar clinicopathological features, some have a better prognosis than others. Identification of molecular alterations responsible for this may contribute to a greater understanding of tumor behavior. Tissue microarray (TMA) approach is a high throughput technology that enables analysis of multiple molecular targets simultaneously without causing any morphological alteration to tissue specimens. Aim and Objective : To assess the tumor behavior based on the expression of p53, Bcl-2 and E-cadherin using TMA technology. Settings and Design : This was a case series analysis using tissue microarray technology. Materials and Methods : Formalin-fixed Paraffin-embedded (FFPE) tissue blocks of histological proven cases of OSCC (n = 30) were retrieved from the department archives. Tissue microarray blocks were constructed; 4 ΅m thick sections were cut and immunostained for p53, Bcl-2 and E-cadherin. Stastistical Analysis : Mean (SD) was used to summarize age, frequencies with percentages was used to summarize categorical variable and Chi-square test was used to find association between histopathology evaluation and expression of Bcl-2, p53, E-cadherin. Results and Conclusion : Bcl-2 was the most frequently expressed biomarker. The expression of Bcl-2 was inversely related to the degree of differentiation (P = 0.005). The follow-up data showed that 63.6% of the cases that were positive for both Bcl-2 and E-cadherin were disease-free following treatment. Tissue microarray technology is a promising way to analyse multiple biomarkers simultaneously. The molecular data obtained from TMA will enhance diagnosis, provide better prognostication and will improve cancer treatment for individual patients.

Glandular odontogenic cyst. A rare entity with aggressive biological behaviour. A case report.

Glandular Odontogenic cyst is an apparently rare jaw cyst characterised by typical histopathological features, propensity to reach large size and high rate of local recurrence, if not adequately treated. Identification of this cyst as a separate entity is important because of the difference in biological behaviour. We report a case of Glandular Odontogenic cyst occurring in maxilla.