Assessing immuno-expression of p53 protein and TP 53 gene amplification in histologically negative surgical margins of oral squamous cell carcinoma patients and normal oral mucosa.

OBJECTIVE: To assess and compare the immuno-expression of p53 and TP 53 gene amplification and correlate local recurrence and survival in histologically negative surgical margins of oral squamous cell carcinoma (OSCC) with normal oral mucosa. METHODS: Forty formalin-fixed paraffin-embedded tissue blocks of HNMs of OSCC and 40 normal oral mucosa samples were analyzed for p53 immunostaining and TP 53 gene amplification by PCR. RESULTS: Significantly, higher positivity was noted with p53 immuno-expression, TP53 gene amplification, and combined p53 and TP53 expression in the study group compared to the control group (C0.05). Most cases that were positive for p53 immuno-expression, TP 53 gene amplification, and combined p53 and TP53 expression showed local recurrence and poor survival. Kaplan-Meier survival analysis showed that subjects with TP53 and combined p53 and TP53 positivity had decreased survival rate than their negative counterparts. CONCLUSION: Detection of p53 in HNMs of OSCC can be used as a biomarker to identify patients at a higher risk of developing local recurrence and to predict survival. CLINICAL RELEVANCE: Combined p53 and TP 53 assessment may be more reliable for predicting LR to help clinicians and surgeons in treatment planning.

Immunoexpression of p53 in histologically negative surgical margins adjacent to oral squamous cell carcinoma: A preliminary study.

The prognostic significance of genetic changes occurring in the histologically negative surgical margins (HNMs) has been focus of various studies recently. Since p53 is the most frequently observed genetic alteration found in oral squamous cell carcinoma (OSCC), we hypothesized that a similar variation might be evident in HNMs as well. Literature is scarce regarding comparison of expression of p53 in the tumor tissue and its adjacent HNMs; hence, the aim of the present study was to study p53 immunoexpression in OSCC and its HNMs. We included 12 paraffin-embedded tissue blocks of OSCC having tumor tissue and HNMs. The samples were subjected to immunohistochemical staining using primary mouse monoclonal antibody against p53, and the stained slides were evaluated for staining intensity and percentage of expression. Descriptive analysis and Chi-square test were applied. The expression of p53 was observed in 66% of HNMs and 91.6% of tumor tissue. The three cases which showed local recurrence demonstrated the expression of p53 in HNM. Hence, molecular analysis of p53 in surgical margins might potentially predict local recurrence of OSCC.

Primary melanoma of oral mucosa: A case report and review of literature.

Primary oral melanoma is a rare neoplasm of melanocytic origin, accounting for 0.5% of all oral malignancies. The "chameleonic" presentation of a mainly asymptomatic condition, rarity of this lesion, poor prognosis, and the necessity of a highly specialized treatment are factors that should be seriously considered by the involved health provider. Here is a case report presenting a malignant melanoma of oral mucosa in 48-year-old male patient on maxillary gingiva. The lesion was removed by partial maxillectomy and patient is disease free after 11 months of regular followup. This case provides an example of how dental clinicians play a major role in the identification of pigmented lesions of oral cavity and also emphasize on the fact that any pigmented lesion detected in the oral cavity may exhibit potential growth and should be submitted to biopsy to exclude malignancy.

Oral Candida carriage, quantification, and species characterization in oral submucous fibrosis patients and healthy individuals.

AIM: To determine the prevalence of oral Candida carriage, candidal quantification, and various subtypes of Candida species in oral submucous fibrosis patients and healthy individuals. METHODS: The study comprised 30 clinically-diagnosed and -staged oral submucous fibrosis patients aged 20-40 years, and 20 age- and sex-matched controls. Buccal mucosa was sampled by sterile swab technique. Each sample was inoculated on Sabouraud's dextrose agar and CHROMagar culture media. Candida species identification was done using the KB006 Candida identification kit. RESULTS: Eleven (36.67%) cases in the study group, and two (10%) cases in the control group, yielded Candida on culture. The value of CFU/mL increased with an increased duration of betel quid chewing habit. All Candida-positive oral submucous fibrosis patients complained of a burning sensation. Candida albicans and Candida tropicalis were the most common species in the oral submucous fibrosis cases. Candida dubliniensis was isolated in both the study and control groups. CONCLUSIONS: Our observations in this study affirm that oral submucous fibrosis favors the colonization of Candida. Mucosal alterations due to the underlying disease process or betel quid chewing, coupled with other factors, might lead to candidal colonization, even in the absence of clinically-related mycotic manifestations.