Andrea Gabusi

Predictive Role of p53 Protein as a Single Marker or Associated with ki67 Antigen in Oral Leukoplakia: A Retrospective Longitudinal Study

Oral leukoplakia (OL) is the most common potentially malignant lesion of the oral cavity. Immunohistochemical analysis of p53 and Ki67 proteins is a simple and inexpensive method widely used in non-dysplastic OLs to reveal lesions predicted to develop oral cancer. The present longitudinal study evaluated the predictive role of p53 and Ki67 proteins alone or in combination in a group of OLs without dysplasia followed for many years. Seventy-seven OL patients referred to our Department between January 2006 and October 2013 underwent histochemical analysis of p53 and Ki67 expression. OLs were considered at high risk in the presence of either high p53 expression (>20%), or low/normal p53 expression associated with high Ki67 expression (Ki67/p53 ratio >3). Seven OLs evolved to OSCC during the follow-up period. Three cases had p53 overexpression, while four had a high Ki67/p53 ratio. Statistical significance was reached when samples with p53 overexpression were combined with samples with high Ki67/p53 ratio (Chi square 5.3; p<0.02). The combined immunohistochemical expression of p53 and Ki67 proteins could be a useful and simple molecular marker for early detection of non-dysplastic OLs at risk of developing oral cancer.

Histological and immunohistochemical evaluation of new epithelium after removal of oral leukoplakia with Nd:YAG laser treatment

Laser excision has been used with increasing success to treat oral leukoplakia. The aim of the present study was to evaluate whether clinical healing of a leukoplakia after laser surgery is associated with a normal functional status of the new epithelium and whether pathological alterations in these parameters are related to the risk of local recurrence. The study population consisted of 13 consecutive patients with oral leukoplakia in which clinical healing was achieved after laser therapy using an Nd:YAG laser (Model 6000, Laser Sonics, Cooper Laser Sonics). At the end of the therapy, all patients underwent a second biopsy of the clinically healthy tissue. Epithelial cell turnover was evaluated before and after laser surgery by Ki67 protein expression, and positive staining of more than 20% was considered abnormal. All patients were followed on a monthly basis. Eight patients had abnormally high Ki67 values before laser therapy (mean 27.4 ± 6.2%), but the levels decreased significantly after treatment (17.6 ± 8.5%; t = 2.6, p < 0.05). High Ki67 values persisted in three patients, and local recurrences in the new epithelium was observed in two of these patients. Kaplan–Meier statistics showed that the between-group difference was statistically significant (Chi square 7.3; p < 0.01). In conclusion, this is the first prospective study to show that clinical healing of leukoplakia treated by laser surgery may be accompanied by altered cell turnover in 20% of the cases. Ki67, as a marker of proliferative status, may be a prognostic indicator in the mucosa replacing the lesion.

Paraesthesia after local anaesthetics: an analysis of reports to the FDA Adverse Event Reporting System.

This study was aimed to evaluate the possible alert signals of paraesthesia by local anaesthetics, focusing on those used in dentistry. A case/non‐case study of spontaneous adverse events recorded in FAERS (FDA Adverse Event Reporting System) between 2004 and 2011 was performed. Cases were represented by the reports of reactions grouped under the term ‘Paraesthesias and dysaesthesias’ involving local anaesthetics (ATC: N01B*); non‐cases were all other reports of the same drugs. Reporting odds ratios (ROR) with the relevant 95% confidence intervals (95CI) were calculated. Alert signal was considered when number of cases >3 and lower limit of ROR 95CI > 1. To estimate the specificity of signals for dentistry, the analysis was restricted to the specific term “Oral Paraesthesia” and to reports concerning dental practice. Overall, 528 reports of ‘Paraesthesias and dysaesthesias’ were retrieved, corresponding to 573 drug–reaction pairs (247 lidocaine, 99 bupivacaine, 85 articaine, 30 prilocaine, 112 others). The signal was significant only for articaine (ROR=18.38; 95CI = 13.95–24.21) and prilocaine (2.66; 1.82–3.90). The analysis of the specific term “Oral Paraesthesia” retrieved 82 reports corresponding to 90 drug–reaction pairs (37 articaine, 19 lidocaine, 14 prilocaine, 7 bupivacaine, 13 others) and confirmed the signal for articaine (58.77; 37.82–91.31) and prilocaine (8.73; 4.89–15.57). The analysis of reports concerning dental procedures retrieved a signal for articaine, both for any procedures (8.84; 2.79–27.97) and for non‐surgical ones (15.79; 1.87–133.46). In conclusion, among local anaesthetics, only articaine and prilocaine generated a signal of paraesthesia, especially when used in dentistry.

Clonal analysis as a prognostic factor in multiple oral squamous cell carcinoma

OBJECTIVES A novel classification based on molecular methods to assess clonality defines three types of secondary oral squamous cell carcinoma (OSCC): second primary tumour (SPT) independent from the index tumour, local recurrence (LR), clonally related to the primary tumour, and second field tumour (SFT), derived from the same genetically altered mucosal field as the primary tumour. The present study applied mtDNA analysis in a group of patients experiencing a second loco-regional neoplastic manifestation. The purpose was to differentiate secondary tumours into LRs, SPTs and SFTs and evaluate the prognostic impact in terms of survival rate. MATERIAL AND METHODS The study population comprised 23 patients who experienced a second neoplastic lesion after a surgical resection of primary OSCC. mtDNA D-loop analysis was applied in paired neoplastic lesions and in clinically and histologically normal mucosa. On the basis of mtDNA results, the second OSCC was classified as LR or SPT or SFT. Disease-free survival was defined as the duration between the appearance of the second neoplastic lesion and death of disease, or last follow-up visit. RESULTS Seven secondary tumours were classified as LR, 12 as SFT, 4 as SPT. An altered mucosal field proved a variable significantly related to a better survival rate (p<0.05); 2/12 (16.6%) SFT events failed as compared to 5/7 LRs (71.4%) and 3/4 SPTs (75%). CONCLUSION mtDNA analysis may be considered a useful tool to differentiate secondary tumours and might influence the choice of the most appropriate treatment in patients with multiple OSCCs.

A Noninvasive Test for MicroRNA Expression in Oral Squamous Cell Carcinoma

MicroRNAs have recently been proposed as non-invasive biomarkers in Oral Squamous Cell Carcinoma (OSCC). The aim of this study was to analyze the expression of a panel of miRNAs in epithelial cells collected by oral brushing from OSCCs from regenerative areas after OSCC surgical resection and from their respective normal distant mucosa. Oral brushing specimens were collected from 24 healthy donors, 14 OSCC patients with specimens from tumour and normal distant mucosa, and from 13 patients who had OSCC resection, with samples from regenerative areas after OSCC resection and normal distant mucosa. Expression levels of eight targets (miR-21, miR-375, miR-345, miR-181b, miR-146a, miR-649, miR-518b, and miR-191) were evaluated by real-time Polymerase Chain Reaction (PCR). A highly significant between-group difference was found for miR-21 (F = 6.58, p < 0.001), miR-146a (F = 6.974, p < 0.001), and miR-191 (F = 17.07, p < 0.001). The major difference was observed between samples from healthy donors and from OSCC brushing, whereas no significant differences were observed between areas infiltrated by OSCC and their respective normal distant mucosa. Furthermore, altered expression of miR-146a and miR-191 was also observed in regenerative areas after OSCC resection. Conclusions: Oral brushing could be proposed as a noninvasive method to study microRNA expression in oral mucosa in OSCC patients.

Two Unusual Cases of Oral Lichen Planus Arising After Oral Squamous Cell Carcinoma: Can Oral Cancer Trigger Autoimmunity?:

Autoimmune diseases occur when the immune system fails to recognize self-antigens expressed on the body’s own cells and attacks them. Oral lichen planus (OLP) is a chronic autoimmune mucocutaneous disease of the oral cavity characterized by white/red lesions. Considered a potentially malignant disorder, OLP evolution into oral squamous cell carcinoma (OSCC) is still a matter of debate. While chronic autoimmune inflammation is considered a potential risk factor for malignant transformation in many solid tumors, the opposite idea that cancer may trigger autoimmune responses remains controversial. We describe 2 patients who developed lesions clinically suggestive of OLP with histological evidence of lichenoid infiltration some time after OSCC removal, even in areas far from the neoplastic site. Neither patient had OLP before the diagnosis of OSCC, or reported exposure to OLP-associated etiologic factors, and neither. experienced tumor recurrence during follow-up. Our findings suggest that oral cancer remission may be linked to OLP development, but further studies are necessary to unveil the underlying mechanisms and possible prognostic implications.

Unusual Histological Evidence of Dysplasia in a Case of Oral Pemphigus Vulgaris: A Potential Diagnostic Challenge.

This report describes the management of an unusual case of oral pemphigus vulgaris (PV). The patient was referred for a painful single bullous lesion together with a small proliferative area localized in the soft palate. Histology and direct immunofluorescence data were consistent for PV but disclosed unusual signs of high-grade dysplasia in the proliferative area. At surgical removal of the dysplastic area 1 week after the start of cortisone therapy there was no evidence of dysplasia. Histological signs of high-grade dysplasia in oral mucosa are often associated with concurrent or subsequent carcinoma. However, severe inflammation may induce reactive epithelial cell changes and hence mimic histologic dysplasia. Pathologic evaluation of dysplasia in an inflammatory disease like PV may be a diagnostic challenge and a careful pathological evaluation is advisable before choosing between surgical and medical approach.