Predictors of malignant transformation in oral leukoplakia and proliferative verrucous leukoplakia: An observational prospective study including the DNA ploidy status.

BACKGROUND: This prospective observational study investigated the determinants of malignant transformation (MT) in localized oral leukoplakia (OL) and proliferative verrucous leukoplakia (PVL). METHODS: Demographic, clinical, histological, and DNA ploidy status data were collected at enrolment. Survival analysis was performed (MT being the event of interest). RESULTS: One-hundred and thirty-three patients with OL and 20 patients with PVL entered the study over 6 years (mean follow-up 7.8 years). The presence of OED, DNA ploidy, clinical presentation, and lesion site were associated with MT in patients with OL in a univariate analysis. In a multivariate model, OED was the strongest predictor of MT in patients with OL. Adding DNA ploidy increased the model's predictive power. None of the assessed predictors was associated with MT in patients with PVL. CONCLUSIONS: DNA ploidy might identify a subset OL with low risk or minimal risk of MT, but it does not seem to be a reliable predictor in patients with PVL.

Interobserver and intraobserver variability affecting the assessment of loss of autofluorescence of oral mucosal lesions.

OBJECTIVES: The assessment of loss of tissue autofluorescence (LAF) has been proposed as an adjunct to comprehensive oral examination to enhance the detection of mucosal lesions harbouring dysplasia or carcinoma. The assessment of LAF is not based on completely objectified parameters therefore intraobserver and interobserver variability cannot be neglected alongside the issue of correct interpretation of LAF. The present study evaluated intraobserver and interobserver variability in the clinical assessment of LAF as performed by oral medicine practitioners (OMPs) or general dental practitioners (GDPs). MATERIALS AND METHODS: Couples of clinical pictures, acquired under white incandescent dental operatory light and during the assessment of LAF performed by VELscope were retrieved. Four OMPs and eight GDPs were asked to assess the pictures and to score the LAF. Kappa statistics allowed the assessment of intra- and inter-observer related variability. RESULTS: Pictures of 109 lesions representative of all oral mucosal sites and clinical appearances were selected. OMPs had a better intraobserver agreement than GDPs (substantial versus moderate). The moderate (k = 0.506) interobserver agreement observed among both OMPs and GDPs in a 2-score model (positive versus negative), lowered down to poor values only among GDPs when a 3-score or 4-score model (including uncertain judgements) was applied. CONCLUSIONS: A good agreement (k>0.8) was never observed and the present results are similar to previously reported data about conventional oral examination. Irrespective of the diagnostic accuracy, the assessment of AF seems not to be able to improve observer-related variability in the clinical assessment of oral mucosal lesions.

Variations of salivary concentration of cytokines and chemokines in presence of oral squamous cell carcinoma. A case-crossover longitudinal prospective study.

Salivary biomarkers represent a promising diagnostic tool. Non-invasive and stress-free sampling results in objective parameters able to overcome the need of clinical expertise required for a correct interpretation of early oral squamous cell carcinoma (OSCC). The present study aims at evaluating potential variations in the salivary concentration of cytokines in presence of OSCC. Twenty patients who underwent surgical resection of OSCC were enrolled in order to assess the variation of the salivary concentration of cytokines and chemokines in a longitudinal prospective case-crossover setting. The salivary concentration of 27 salivary cytokines/chemokines was assessed before and after surgical resection of OSCC. In cases of relapsing/recurrent disease further assessments were performed. In presence of OSCC an increased concentration of IL-8(p = 0.004), IL-6(p = 0.005), VEGF(p = 0.014), MIP-1ß(p = 0.033), IP-10(p = 0.047), IL-1ß(p = 0.049) was observed; conversely the concentration of IFN-γ(p = 0.036) and IL-5(P = 0.048) decreased. In cases with relapsing/recurrent disease IL-5, IL-6 and MIP-1ß showed variations consistent with the previously reported results. Further studies are needed in order to confirm these results and to determine reference values to determine the presence or absence of disease.

DNA aneuploidy relationship with patient age and tobacco smoke in OPMDs/OSCCs.

The aim of this study was to investigate the relationship between tobacco smoke habit, patient age, DNA aneuploidy and genomic DNA copy number aberrations (CNAs) in oral potentially malignant disorder (OPMD) and oral squamous cell carcinoma (OSCC) patients. DNA aneuploidy was detected by high-resolution DNA flow cytometry (hr DNA-FCM) on DAPI stained nuclei obtained from multiple tissue samples from OPMDs/OSCCs in 220 consecutive patients. Nuclear genomic aberrations were determined in a subset of 65 patients by genome-wide array comparative genomic hybridization (aCGH) using DNA extracted from either diploid or aneuploid nuclei suspension sorted by FCM. DNA aneuploidy and mean nuclear genomic aberrations were associated with patients' age. In particular, DNA aneuploidy strongly associated with age in non-smoker OPMDs/OSCCs patients. OSCCs from smokers showed a lower prevalence of DNA aneuploidy compared to OSCCs from non-smokers. A higher occurrence of DNA aneuploidy (particularly in smokers' OPMDs) was observed in patients characterized by involvement of a single oral subsite. Our study suggests that: 1) DNA aneuploidy in non-smokers is mainly related to aging; 2) OPMDs/OSCCs involving multiple oral subsites in smokers are less likely to develop DNA aneuploidy compared to non-smokers; 3) OSCC development is characterized by both CIN and CIN-independent mechanisms and that the latter are more relevant in smokers. This study provides evidence that DNA diploid OPMDs may be considered at lower risk of cancerization than DNA aneuploid ones in non-smokers but not in smokers.

Physics and Histologic Evaluation of Rotary, Ultrasonic, and Sonic Instruments.

Rotary instruments (RIs) are the most commonly used to perform osteotomies in many fields of medicine. Owing to a new interest in performing a minimally invasive surgery, over last fifteen years new devices have been used in oral surgery such as ultrasonic instruments (UIs) and, lately, sonic instruments (SIs). Nowadays, bone preservation and regeneration are paramount in many clinical situations and, consequently, it is crucial to rely upon instruments, which cause the least tissue damage during the surgery. Concerning SIs, there is still few information about workload to be applied and related temperature increases; furthermore, there are no comparative in-vivo studies, which analyze the thermal and mechanical effects on bone. Thus, SIs have been compared with UIs and RIs in terms of heat generation, operating time, accuracy, and tissue damage. Decalcification and sectioning procedure resulted in no significant differences between the applied instruments in terms of bone damage. RIs resulted more efficient than UIs (P < 0.001), but demonstrated low accuracy (NRS 4.9), whereas SIs (P = 0.005) required more time to perform the osteotomy. The maximum temperature increase occurred in the ultrasonic group. Even though SI were the slowest, they have proved to be the most accurate (NRS 8.4) in comparison with UI (NRS 7.6) and RI (NRS 4.9). Within the limit of this study, sonic instruments could be considered a safe alternative to ultrasonic instruments.

Genomic DNA Copy Number Aberrations, Histological Diagnosis, Oral Subsite and Aneuploidy in OPMDs/OSCCs.

Oral potentially malignant disorders (OPMDs) characterized by the presence of dysplasia and DNA copy number aberrations (CNAs), may reflect chromosomal instability (CIN) and predispose to oral squamous cell carcinoma (OSCC). Early detection of OPMDs with such characteristics may play a crucial role in OSCC prevention. The aim of this study was to explore the relationship between CNAs, histological diagnosis, oral subsite and aneuploidy in OPMDs/OSCCs. Samples from OPMDs and OSCCs were processed by high-resolution DNA flow cytometry (hr DNA-FCM) to determine the relative nuclear DNA content. Additionally, CNAs were obtained for a subset of these samples by genome-wide array comparative genomic hybridization (aCGH) using DNA extracted from either diploid or aneuploid nuclei suspension sorted by FCM. Our study shows that: i) aneuploidy, global genomic imbalance (measured as the total number of CNAs) and specific focal CNAs occur early in the development of oral cancer and become more frequent at later stages; ii) OPMDs limited to tongue (TNG) mucosa display a higher frequency of aneuploidy compared to OPMDs confined to buccal mucosa (BM) as measured by DNA-FCM; iii) TNG OPMDs/OSCCs show peculiar features of CIN compared to BM OPMDs/OSCCs given the preferential association with total broad and specific focal CNA gains. Follow-up studies are warranted to establish whether the presence of DNA aneuploidy and specific focal or broad CNAs may predict cancer development in non-dysplastic OPMDs.

A novel genomic signature reclassifies an oral cancer subtype.

Verrucous carcinoma of the oral cavity (OVC) is considered a subtype of classical oral squamous cell carcinoma (OSCC). Diagnosis is problematic, and additional biomarkers are needed to better stratify patients. To investigate their molecular signature, we performed low-coverage copy number (CN) sequencing on 57 OVC and exome and RNA sequencing on a subset of these and compared the data to the same OSCC parameters. CN results showed that OVC lacked any of the classical OSCC patterns such as gain of 3q and loss of 3p and demonstrated considerably fewer genomic rearrangements compared to the OSCC cohort. OVC and OSCC samples could be clearly differentiated. Exome sequencing showed that OVC samples lacked mutations in genes commonly associated with OSCC (TP53, NOTCH1, NOTCH2, CDKN2A and FAT1). RNA sequencing identified genes that were differentially expressed between the groups. In silico functional analysis showed that the mutated and differentially expressed genes in OVC samples were involved in cell adhesion and keratinocyte proliferation, while those in the OSCC cohort were enriched for cell death and apoptosis pathways. This is the largest and most detailed genomic and transcriptomic analysis yet performed on this tumour type, which, as an example of non-metastatic cancer, may shed light on the nature of metastases. These three independent investigations consistently show substantial differences between the cohorts. Taken together, they lead to the conclusion that OVC is not a subtype of OSCC, but should be classified as a distinct entity.

Peculiar alexithymic traits in burning mouth syndrome: case-control study.

OBJECTIVES: The present case-control study aims to assess the occurrence of alexithymic traits in burning mouth syndrome (BMS) subjects and to correlate alexithymic traits to anxious and depressive traits in BMS subjects. MATERIALS AND METHODS: Prospectively enrolled BMS and control subjects were administered the 20-item Toronto Alexithymia Scale (TAS-20). Anxiety and depressive traits were assessed using the Hamilton Anxiety Rating Scale and the Montgomery and Asberg Depression Rating Scale. Occurrence of alexithymic traits was compared between BMS and control subjects. Correlation tests were used to measure the importance of alexithymic traits related to demographic characteristics, pain intensity (VAS score), and to the other psychometric scores. RESULTS: Fifty-eight BMS subjects (46 females and 12 males) had a mean TAS-20 score significantly higher when compared to controls (p < 0.001; r = 0.72), corresponding to an occurrence rate of alexithymic traits of 79.3 versus 6.9%. Alexithymic traits in BMS subjects were just related to depressive traits (p = 0.02; ρ = 0.31). CONCLUSIONS: The high occurrence of alexithymia in BMS is an adjunctive issue in favor of its multifactorial pathogenesis, with a not negligible role for somatization. CLINICAL RELEVANCE: Clinicians should be aware of the high occurrence of alexithymic traits among BMS subjects as such traits may affect the doctor-patient relationship.

Next-generation sequencing analysis for detecting human papillomavirus in oral verrucous carcinoma.

OBJECTIVE: The etiology of oral verrucous carcinoma is unknown, and human papillomavirus 'involvement' remains contentious. The uncertainty can be attributed to varied detection procedures and difficulties in defining 'gold-standard' histologic criteria for diagnosing 'verrucous' lesions. Their paucity also hampers investigation. We aimed to analyze oral verrucous lesions for human papillomavirus (HPV) subtype genomes. STUDY DESIGN: We used next-generation sequencing for the detection of papillomavirus sequences, identifying subtypes and computing viral loads. We identified a total of 78 oral verrucous cases (62 carcinomas and 16 hyperplasias). DNA was extracted from all and sequenced at a coverage between 2.5% and 13%. RESULTS: An HPV-16 sequence was detected in 1 carcinoma and 1 hyperplasia, and an HPV-2 sequence was detected in 1 carcinoma out of the 78 cases, with viral loads of 2.24, 8.16, and 0.33 viral genomes per cell, respectively. CONCLUSIONS: Our results indicate no conclusive human papillomavirus involvement in oral verrucous carcinoma or hyperplasia.

Differential expression of HER2, STAT3, SOX2, IFI16 and cell cycle markers during HPV-related head and neck carcinogenesis.

The aim of this study was to analyze protein and gene expression of HER2 in 224 head and neck precancerous and malignant lesions by immunohistochemistry and FISH analysis. In parallel, expression of pStat3, Sox2, IFI16 and p16, Ki67 was evaluated. Immunohistochemical analysis was assessed on formalin-fixed paraffin-embedded (FFPE) tissue specimens. A combined method for HPV detection consisting of p16 immunostaining and two PCR probes was applied. HER2 gene status was evaluated by FISH analysis. HPV DNA was detected in 24% of cases with predominant HPV16 genotype. HPV-positive lesions had higher HER2, pStat3 and within carcinoma group, and higher IFI16 expression compared to the HPV-negative group (Fig. 1A-B-C). A strong positive correlation between Sox2 and proliferative activity was observed, whereas IFI16 expression displayed a negative relationship with Sox2 and Ki67 activity. The most striking result was higher pStat3 expression in HPV-positive lesions and its strong positive correlation with IFI16 expression. The presence of HPV may induce upregulation of HER2/neu, pStat3 and IFI16. High levels and a strong positive correlation between pStat3 and IFI16 suggest their synergistic pro-apoptotic effects in HPV-positive lesions.

Microbiopsy a novel sampling technique to early detect dysplastic/malignant alterations in oral mucosal lesions: practicability by general dentists.

BACKGROUND: When used in oral medicine clinics, microbiopsy is able to obtain tissue fragments suitable for a highly sensitive first-level diagnosis of dysplastic/malignant alterations in oral mucosal lesions. If feasible by general dentists, this sampling technique could reduce the diagnostic delay for oral malignant and premalignant lesions. This study assesses the adequacy of microbiopsy samples when taken by general dentists. METHODS: Fifty dentists, without specific training on oral medicine, volunteered for enrolment. They were given brief training and asked to prospectively sample any mucosal lesion observed during their routine practice. The sample adequacy features were assessed. RESULTS: The dentists sampled 152 lesions; there were 92.1% of adequate samples (140/152), and the BMZ was visible in 78.6% of these (110/140). Neither the clinical aspect nor lesion site affected either the adequacy or the presence of BMZ. CONCLUSIONS: The high adequacy rate observed and the advantages histological specimens have over cytological ones go to support the feasibility of microbiopsy taken by general dentists for the characterization of oral mucosal lesions and in selecting those requiring further assessment in specialized oral medicine centres.

Impact of academic and continuing education on oral cancer knowledge, attitude and practice among dentists in north-western Italy.

The present study aims to assess the knowledge, attitude and practice of dentists practicing in the Turin Province (north-western Italy) regarding oral cancer prevention and early detection, to weigh the impact of academic and continuing education and to compare actual and perceived knowledge/practice. A survey was prospectively carried out using an anonymous 23-item questionnaire. Bivariate analyses, multivariate logistic regression analyses and Spearman's correlation analyses examined the overall effect of demographic/background characteristics of responders, with particular emphasis on academic and continuing education. The responder group was formed by 450 dentists representative of the Turin Province Council of Dentists. Both academic and continuing education have a significant impact on knowledge, with a significant association between the time elapsed from continuing education and the degree of knowledge. Knowledge acquired during graduation is seen to significantly weaken in the absence of continuing education. The present study highlights the need of both thorough academic curricula and compulsory current continuing education.

Choristoma involving the floor of the mouth and the anterior tongue: a case of teratoid cyst with gastric and respiratory epithelia.

Oral dysontogenic cysts result from defective embryonic development. Among them teratoid cysts are the most unusual presentation and may be lined by gastric, intestinal, respiratory, squamous, ciliated epithelium or even pancreatic structures. Teratoid cysts containing respiratory and gastrointestinal epithelium have typically been called choristomas. This article describes a 15-year-old boy presenting a choristoma involving both the floor of the mouth and the anterior tongue and characterized by the presence of squamous epithelium with skin adnexa, gastric and respiratory epithelium.

Chromosomal instability, DNA index, dysplasia, and subsite in oral premalignancy as intermediate endpoints of risk of cancer.

BACKGROUND: Chromosomal instability and aneuploidy may represent biomarkers of oral exposure to damaging agents and early signs of clinical disease according to the theory of "oral field cancerization." METHODS: The hypothesis was tested that the DNA index (DI) values, obtained by high-resolution DNA flow cytometry (DNA-FCM), may potentially contribute to oral cancer risk prediction. For this purpose, the DI of oral fields of normal-appearing mucosa and oral potentially malignant disorders (OPMDs) in 165 consecutive patients was tested for association with dysplasia and/or the oral subsites of tongue and floor of the mouth taken as high-risk intermediate endpoints surrogate of cancer clinical endpoints. The association was evaluated by logistic regression using patient gender, age, tobacco, cigarette smoking habit, and alcohol abuse as confounding variables. RESULTS: Different DI models provided evidence of statistical significant associations. Subdividing the DI values in diploid, near-diploid aneuploid, and high or multiple aneuploid from both OPMDs and oral normal-appearing mucosa, ORs, respectively, of 1, 4.3 (P = 0.001), and 18.4 (P < 0.0005) were obtained. CONCLUSION: Routine DI analysis by high-resolution DNA-FCM seems potentially useful to complement dysplasia and subsite analysis for assessment of oral cancer risk prediction and for a better management of the patients with OPMDs. Work is in progress to validate the present findings in a prospective study with clinical endpoints. IMPACT: Identifying DNA abnormalities in oral premalignancy may lead to biomarkers of oral exposure and cancer risk and potentially to more effective prevention measures.

Chromosomal instability, aneuploidy and routine high-resolution DNA content analysis in oral cancer risk evaluation.

Carcinogen exposure of the oral cavity is thought to create an extensive 'field cancerization'. According to this model, a very early precursor of oral cancer is a patch of normal-appearing mucosa in which stem cells share genetic/genomic aberrations. These precancerous fields then become clinically visible as white and red lesions (leuko- and erythro-plakias), which represent the vast majority of the oral potentially malignant disorders. This review focuses on aneuploidy (where it is from) and on biomarkers associated with DNA aneuploidy in oral mucosa and oral potentially malignant disorders, as detected by DNA image and flow cytometry. Data from the literature strongly support the association of DNA ploidy with dysplasia. However, work is still needed to prove the clinical value of DNA ploidy in large-scale prospective studies. Using high-resolution DNA flow cytometry with fresh/frozen material and the degree of DNA aneuploidy (DNA Index) might improve the prediction of risk of oral cancer development.

Clinical and histological features of gingival lesions: A 17-year retrospective analysis in a northern Italian population

Objectives: Only few studies on gingival lesions considered large enough populations and contemporary literature does not provide a valid report regarding the epidemiology of gingival lesions within the Italian population. The histopathological and clinical appearance of 538 gingival lesions from northern Italians are described and discussed here.Study Design: The case records of patients referred for the diagnosis and management of gingival lesions, from October 1993 to October 2009, were reviewed. Data regarding the histological type of lesion were also obtained from the biopsy register for each case, and blindly re-examined.Results: We reported a greater frequency of benign lesions (reactive and/or inflammatory) in non-plaque/noncalculus induced gingival disorders. We confirmed an unambiguous prevalence of oral squamous cell carcinoma above all other malignant neoplasia, and a prevalence of neoplastic malignant lesions in the maxilla, with a slight increase in females and a drift of the incidence peak from the seventh to the eighth decade. There was a prevalence of precancerous gingival lesions in the maxilla, with a higher incidence in females and with a drift from the sixth to the seventh decade. We also reported a prevalence of oral lichen planus and lichenoid lesions as major manifestations of desquamative gingivitis.Conclusions: The high frequency of gingival involvement of such different diseases emphasizes the importance of histological characterization and differential diagnosis for periodontists, but more prospective studies are needed to better describe the true incidence of the non-plaque related gingival diseases (AU)

Clinical and histological features of gingival lesions: a 17-year retrospective analysis in a northern Italian population.

OBJECTIVES: Only few studies on gingival lesions considered large enough populations and contemporary literature does not provide a valid report regarding the epidemiology of gingival lesions within the Italian population. The histopathological and clinical appearance of 538 gingival lesions from northern Italians are described and discussed here. STUDY DESIGN: The case records of patients referred for the diagnosis and management of gingival lesions, from October 1993 to October 2009, were reviewed. Data regarding the histological type of lesion were also obtained from the biopsy register for each case, and blindly re-examined. RESULTS: We reported a greater frequency of benign lesions (reactive and/or inflammatory) in non-plaque/non-calculus induced gingival disorders. We confirmed an unambiguous prevalence of oral squamous cell carcinoma above all other malignant neoplasia, and a prevalence of neoplastic malignant lesions in the maxilla, with a slight increase in females and a drift of the incidence peak from the seventh to the eighth decade. There was a prevalence of precancerous gingival lesions in the maxilla, with a higher incidence in females and with a drift from the sixth to the seventh decade. We also reported a prevalence of oral lichen planus and lichenoid lesions as major manifestations of desquamative gingivitis. CONCLUSIONS: The high frequency of gingival involvement of such different diseases emphasizes the importance of histological characterization and differential diagnosis for periodontists, but more prospective studies are needed to better describe the true incidence of the non-plaque related gingival diseases.

Field effect in oral precancer as assessed by DNA flow cytometry and array-CGH.

OBJECTIVE: 'Field cancerization' is an accepted model for oral carcinogenesis. So far, genetically altered fields have been just reported in the presence of carcinomas. This study assessed the distant mirror fields (MFs) of oral precancer by DNA high-resolution flow cytometry (hr DNA-FCM) and array-Comparative Genomic Hybridization (a-CGH). METHODS: Five leukoplakias without dysplasia (OLs), seven dysplastic leukoplakias (DOLs), and 12 corresponding visually normal and non-dysplastic MFs were analyzed. DNA aneuploidy (DNA Index, DI ≠ 1) was detected by hr DNA-FCM on DAPI stained nuclei suspensions. The epithelial DNA aneuploid subclones were FCM-sorted to obtain genomic DNA for a-CGH. RESULTS: Mirror fields, OLs, and DOLs showed increasing prevalence of DNA aneuploidy of, respectively, 8%, 20%, and 57%. The average number of chromosome aberrations (Ch-Abs) was 2.8 in MFs, 3 in OLs, and 10.6 in DOLs. MFs relative to OLs and DOLs had average numbers of Ch-Abs, respectively, of 1.8 and 3.6. Ch-Abs were also observed in DNA diploid sublines, and often the same aberrations were observed in both MFs and corresponding OLs/DOLs. CONCLUSION: DNA aneuploidy and Ch-Abs in MFs, the last ones being mainly gains, indicate an early onset of field effect in oral carcinogenesis.

Chromosomal aberrations and aneuploidy in oral potentially malignant lesions: distinctive features for tongue.

BACKGROUND: The mucosae of the oral cavity are different at the histological level but appear all equally exposed to common genotoxic agents. As a result of this exposure, changes in the mucosal epithelia may develop giving rise to Oral Potentially Malignant Lesions (OPMLs), which with time may in turn progress to Oral Squamous Cell Carcinomas (OSCCs). Therefore, much effort should be devoted to identify features able to predict the likeliness of progression associated with an OPML. Such features may be helpful in assisting the clinician to establish both appropriate therapies and follow-up schedules. Here, we report a pilot study that compared the occurrence of DNA aneuploidy and chromosomal copy number aberrations (CNAs) in the OPMLs from different oral anatomical subsites. METHODS: Samples from histologically diagnosed OPMLs were processed for high resolution DNA flow cytometry (hr DNA-FCM) in order to determine the relative DNA content expressed by the DNA index (DI). Additionally, array-Comparative Genomic Hybridization (a-CGH) analysis was performed on DNA obtained from diploid nuclei suspensions directly. When aneuploid nuclei were detected, these were physically separated from diploid nuclei on the base of their DI values by means of a DNA-FCM-Sorter in order to improve the a-CGH analysis. RESULTS: Tongue OPMLs were more frequently associated with DNA aneuploidy and CNAs than OPMLs arising from all the other mucosal subsites. CONCLUSIONS: We suggest that the follow-up and the management of the patients with tongue OPMLs should receive a distinctive special attention. Clearly, this hypothesis should be validated in a prospective clinical study.