Oral Potentially Malignant Disorders and Oral Cancer in Saudi Arabia: An Epidemiological Review of the Literature

Background: Oral potentially malignant disorders (OPMDs) are a group of chronic oral mucosal diseases associated with an increased risk of malignant transformation. Multiple studies have investigated the prevalence of these conditions in multiple regions; however, there are limited data about the prevalence of OPMDs in the Kingdom of Saudi Arabia (KSA). This paper aims to review the prevalence of OPMDs in the KSA, to ensure better understanding of the population risk and propose a more standardised approach to the diagnosis and management of this group across the KSA. In addition, this review will discuss the prevalence of oral cancer in the KSA, considering independent risk factors for oral cancer development. Methods: Electronic databases including PubMed, Medline, Medscape, ScienceDirect, StatPearls, BMC Oral Health and the Cochrane Library were searched with the keywords "Oral Potentially Malignant Disorders"; "Saudi Arabia"; and "Oral Cancer". Identified articles were reviewed independently by 2 reviewers against defined inclusion and exclusion criteria. Results: 16 studies were included in this review. The prevalence of OPMDs in KSA varies significantly depending on age, gender, social habits, background disease and dental status. Conclusions: This review highlights the need for up-to-date data on the prevalence, distribution, and characteristics of OPMDs in KSA. The diverse prevalence rates and distinct characteristics of various OPMDs emphasise the necessity for targeted preventive measures. As the data on OPMDs in KSA remains limited, future research efforts should prioritise the establishment of comprehensive epidemiological studies to inform effective public health interventions in this region.

Dental hygienists and dentists as providers of brush biopsies for oral mucosa screening

BACKGROUND

Oral cancer is a severe and potentially fatal disease usually starting in the squamous epithelium lining the oral cavity. Together with oropharyngeal carcinoma, it is the fifth to sixth most common malignancy worldwide. To limit the increase in the global oral cancer incidence over the past two decades, the World Health Assembly adopted a resolution urging member states to integrate preventive measures such as engagement and training of dental personnel in screening, early diagnosis, and treatment into their national cancer control programs.

AIM

The aim of this study was to investigate if dental hygienists (DHs) and dentists (Ds) in general dental practice care can be entrusted to perform brush sampling of oral potentially malignant disorders (OPMDs), and to evaluate their level of comfort in performing brush biopsies.

METHODS

Participants were five DHs and five Ds who received one day of theoretical and clinical training in oral pathology to identify OPMDs (leukoplakia [LP], erythroplakia [EP], and oral lichen planus [OLP]), and perform brush sampling for PAP cytology and high-risk human papillomavirus (hrHPV) analysis.

RESULTS

Out of 222 collected samples, 215 were adequate for morphological assessment and hrHPV analysis. All the participants agreed that sample collection can be incorporated in DHs and Ds routine clinical duties, and most of them reported that sample collection and processing was easy/quite easy.

CONCLUSION

Dentists and DHs are capable of collecting satisfactory material for cytology and hrHPV analysis. All the participating DHs and Ds were of the opinion that brush sampling could be handled routinely by DHs and Ds in GDP.

Oral Potentially Malignant Disorders: Etiology, Pathogenesis, and Transformation Into Oral Cancer

Among oral diseases, oral cancer is a critical health issue due to its life-threatening potential. Globocan, in its 2020 report, estimated ∼0.37 million new cases of oral cancer, with the majority of them coming from the Asian continent. The WHO has anticipated a rise in the incidences of oral cancer in the coming decades. Various factors, such as genetic, epigenetic, microbial, habitual, and lifestyle factors, are closely associated with oral cancer occurrence and progression. Oral lesions, inherited genetic mutations (dyskeratosis congenital syndrome), and viral infections (HPV) are early signs of oral cancer. Lesions with dysplastic features have been categorized under oral potentially malignant disorders (OPMDs), such as oral leukoplakia, erythroplakia, oral submucous fibrosis (OSMF), and proliferative verrucous leukoplakia, are assumed to have a high risk of malignancy. The incidence and prevalence of OPMDs are recorded as being high in South-Asian countries. Early detection, prevention, and treatment of OPMDs are needed to prevent its malignant transformation into oral cancer. Many advanced diagnostic techniques are used to predict their progression and to assess the risk of malignant transformation. This communication provides insight into the importance of early detection and prevention of OPMDs.

Oral leukoplakia, leukoerythroplakia, erythroplakia and actinic cheilitis: Analysis of 953 patients focusing on oral epithelial dysplasia

BACKGROUND

To analyse the clinical and histological characteristics from a series of oral leukoplakias, leukoerythroplakias, erythroplakias and actinic cheilitis diagnosed in a 14-year period.

METHODS

The files were reviewed and all cases diagnosed as leukoplakia, leukoerythroplakia, erythroplakia and actinic cheilitis were selected. Clinical information was obtained from the biopsy submission forms, and histological review was performed in all cases.

RESULTS

Final sample included 953 lesions, mostly affecting females (534, 56%), and 87.5% of the patients were 41 to 80 years old. The most commonly affected regions were the lower lip (20.1%), tongue (18.1%) and buccal mucosa (16.9%). Leukoplakias, actinic cheilitis, leukoerythroplakias and erythroplakias represented, respectively, 74.6%, 15.2%, 9.3% and 0.8% of the sample. Most cases presented no dysplasia (42.1%) or mild dysplasia (33.5%). Lesions in the tongue, floor of mouth and lower lip, as well as lesions that presented hyperparakeratosis, showed higher frequencies of moderate dysplasia and severe dysplasia/carcinoma in situ. The most common histological criteria were the increase in number and size of nucleoli, loss of polarity of the basal cells and variations in cellular size and shape. Classification by the binary system showed that 7% were high-risk lesions.

CONCLUSION

All histological criteria for classification of oral epithelial dysplasia recommended by the World Health Organization showed increased frequency as grading increased. Additional criteria seem to be useful in grading oral epithelial dysplasia, such as the presence of normal and abnormal superficial mitotic figures and endophytic epithelial proliferation.

Successful GaAlAs low-level laser therapy of self-inflicted thermal burns of the palate

Thermal burns of the oral cavity usually arise from ingestion of hot foods or beverages. A 38-year-old female patient presented with two painful ulcerative erythematous patches of the palate. The patient was consulted on the same day lesions appeared. Medical history was unremarkable. Clinically significant self-inflicted injuries may result in wide ulcers in the mouth and usually do not take less than 2 weeks to heal, whereas our patient, treated with low-level laser therapy, had a complete response in day 4, after 2 days of treatment. The fact that multiple lesions were present signaled against the World Health Organization exclusion diagnosis of erythroplakia for red patches. A traumatic ulcer, regardless of its cause of origin, usually heals within 2 weeks, after the source of injury is resolved. A thermal burn in the oral cavity usually takes longer than that to heal, but whenever this time frame is not respected, the suspicion of a potentially malignant disorder should always arise, and a biopsy should be performed. The present case showed two painful thermal burns with great results in terms of speeding up the relieve of symptoms and healing time with soft laser as opposed to the traditional treatment with oral topical corticosteroid.

Convolutional Neural Network-Based Clinical Predictors of Oral Dysplasia: Class Activation Map Analysis of Deep Learning Results

Oral cancer/oral squamous cell carcinoma is among the top ten most common cancers globally, with over 500,000 new cases and 350,000 associated deaths every year worldwide. There is a critical need for objective, novel technologies that facilitate early, accurate diagnosis. For this purpose, we have developed a method to classify images as "suspicious" and "normal" by performing transfer learning on Inception-ResNet-V2 and generated automated heat maps to highlight the region of the images most likely to be involved in decision making. We have tested the developed method's feasibility on two independent datasets of clinical photographic images of 30 and 24 patients from the UK and Brazil, respectively. Both 10-fold cross-validation and leave-one-patient-out validation methods were performed to test the system, achieving accuracies of 73.6% (±19%) and 90.9% (±12%), F1-scores of 97.9% and 87.2%, and precision values of 95.4% and 99.3% at recall values of 100.0% and 81.1% on these two respective cohorts. This study presents several novel findings and approaches, namely the development and validation of our methods on two datasets collected in different countries showing that using patches instead of the whole lesion image leads to better performance and analyzing which regions of the images are predictive of the classes using class activation map analysis.

Malignant transformation of oral potentially malignant disorders in Taiwan: An observational nationwide population database study

Oral cancer is one of the leading causes of cancer death, which are mostly preceded by oral potentially malignant disorders (OPMDs). Taiwanese government launched a free oral cancer screening program. The aim of this study was to analyze the malignant transformation rate of OPMDs.This study was based on national-wide oral screening databases. 3,362,232 people were enrolled. Patients clinically diagnosed with leukoplakia, erythroplakia, oral submucosal fibrosis (OSF), oral verrucous hyperplasia (OVH), and oral lichen planus (OLP), from 2010 to 2013, were identified. We followed up OPMD patients in cancer registry databases to analyze the malignant transformation rate.The malignant transformation rates from the highest to the lowest were: OVH > OSF > erythroplakia > OLP > leukoplakia. The malignant transformation rate was 24.55, 12.76, 9.75, 4.23, and 0.60 per 1000 person-years in the OVH, OSF, erythroplakia, leukoplakia, and comparison cohort. The hazard ratio was 8.19 times higher in the OPMD group compared with comparison cohort group, after age and habit adjustment. Female patients with OPMDs had a high risk of malignant transformation.Nationwide screening is very important for early diagnosis. OVH had the highest malignant transformation possibility. Female OPMD patients are a rare but have a relatively high malignant transformation rate.

Glottic Keratosis: Significance and Identification of Laryngoscopic Findings

Objective

Glottic keratosis poses a challenge because a decision to biopsy must weigh the likelihood of dysplasia and cancer against the voice outcome after biopsy. We determined the significance of laryngoscopic findings and agreement among clinicians to identify those specific findings.

Study Design

Retrospective case-control study.

Setting

Tertiary care university hospital.

Methods

Adults with glottic keratosis with preoperative office laryngoscopies were included. Preoperative videostroboscopies were reviewed by a blinded reviewer. Multivariable logistic regression was used to examine the correlation between laryngoscopic appearance of glottic keratosis and presence or absence of high-grade dysplasia or carcinoma on biopsies. Consensus among head and neck cancer surgeons to detect specific laryngoscopic findings was evaluated by presenting representative laryngoscopies to a blinded cohort. Interrater reliability was calculated using Fleiss’s κ.

Results

Sixty glottic keratotic lesions met inclusion criteria. On logistic regression, both erythroplakia and aberrant microvasculature like vascular speckling were significantly associated with high-grade dysplasia and carcinoma, P = .002 and P = .03, respectively. Interrater reliability among clinicians to identify erythroplakia and aberrant microvasculature was minimal, κ = 0.35 and κ = 0.29, respectively. Interrater reliability was improved with the use of virtual chromoendoscopy.

Conclusion

The presence of erythroplakia and aberrant microvasculature in glottic keratosis is associated with the presence of high-grade dysplasia or carcinoma. Virtual chromoendoscopy can be used to improve reliability for detecting erythroplakia and vascular speckling, and this is a potential area for practice-based learning. Clinicians should identify and consider immediate diagnostic biopsy of suspicious glottic keratosis.

Oral potentially malignant disorders: A consensus report from an international seminar on nomenclature and classification, convened by the WHO Collaborating Centre for Oral Cancer

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the lip or oral cavity. This paper presents an updated report on the nomenclature and the classification of OPMDs, based predominantly on their clinical features, following discussions by an expert group at a workshop held by the World Health Organization (WHO) Collaborating Centre for Oral Cancer in the UK. The first workshop held in London in 2005 considered a wide spectrum of disorders under the term "potentially malignant disorders of the oral mucosa" (PMD) (now referred to as oral potentially malignant disorders: OPMD) including leukoplakia, erythroplakia, proliferative verrucous leukoplakia, oral lichen planus, oral submucous fibrosis, palatal lesions in reverse smokers, lupus erythematosus, epidermolysis bullosa, and dyskeratosis congenita. Any new evidence published in the intervening period was considered to make essential changes to the 2007 classification. In the current update, most entities were retained with minor changes to their definition. There is sufficient evidence for an increased risk of oral cancer among patients diagnosed with "oral lichenoid lesions" and among those diagnosed with oral manifestations of 'chronic graft-versus-host disease'. These have now been added to the list of OPMDs. There is, to date, insufficient evidence concerning the malignant potential of chronic hyperplastic candidosis and of oral exophytic verrucous hyperplasia to consider these conditions as OPMDs. Furthermore, due to lack of clear evidence of an OPMD in epidermolysis bullosa this was moved to the category with limited evidence. We recommend the establishment of a global research consortium to further study the natural history of OPMDs based on the classification and nomenclature proposed here. This will require multi-center longitudinal studies with uniform diagnostic criteria to improve the identification and cancer risk stratification of patients with OPMDs, link them to evidence-based interventions, with a goal to facilitate the prevention and management of lip and oral cavity cancer.

Oral potentially malignant disorders: A scoping review of prognostic biomarkers

This scoping review aimed to map evidence regarding biomarkers for malignant transformation of oral potentially malignant disorders (OPMD). Seventy-three longitudinal studies investigating prognostic biomarkers for OPMD malignant transformation were included, encompassing 5612 disorders and 108 biomarkers, of which 72 were investigated by immunohistochemistry. Most biomarkers were assessed in one or two studies, while five (p53, Ki-67, podoplanin, p16, and DNA ploidy) were analyzed in five or more studies. All studies investigating podoplanin (n = 8) reported a significant association between positive/high immunoexpression and malignant transformation. Similarly, all studies assessing DNA ploidy (n = 5) found that aneuploidy or gross genomic aberrations were significantly associated with malignant transformation. Included studies often presented mixed data from different OPMD subtypes, inadequate description of population characteristics, and lack of adjusted analysis for confounding factors. One hundred and eight biomarkers were identified and, from these, podoplanin immunoexpression and DNA ploidy were considered promising candidates for future long-term clinical research.

Efficacy of Fluorescence Technology vs Conventional Oral Examination for the Early Detection of Oral Pre-Malignant Lesions. A Clinical Comparative Study

BACKGROUND AND OBJECTIVE

Oral cancer is one of the most common malignancies that affect human beings across the world and early detection of oral cancer is believed to reduce the morbidity significantly. Fluorescence diagnosis is emerging as a promising method in the differentiation of cancerous lesions and thus helping in the determination of resolution for the surgical resection of affected area of malignancy very accurately. The aim of this study was to evaluate the usefulness of an autofluorescence hand held device (OralID) to detect oral premalignant lesions.

METHODS

98 potentially high-risk oral cancer patients were divided into two groups (n=49/group). Both the groups were first examined by conventional oral examination under white light and oral findings were noted. Subjects under group B were further examined under fluorescence light through hand held device, i.e. OralID. After the examinations, a surgical biopsy sample was taken from the suspected lesions under local anaesthesia from both the groups to confirm the diagnosis through histopathological analysis.

RESULTS

The positive potential malignant lesions (PMLs) observed in Group A when compared with biopsy reporting was 89.47% true positive while in Group B was 95.24%. The sensitivity reported of Group A was 89.47% and Group B was 97.56%. We observed 8.09% more sensitivity and 11.36% more specificity when we incorporate adjunctive the fluorescence examination using OralID.

CONCLUSION

Results from this study suggests that OralID is a true adjunct to conventional oral examination in detecting early potential malignant changes in subjects visiting for regular dental check-up.

Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

Periodontal health is defined by absence of clinically detectable inflammation. There is a biological level of immune surveillance that is consistent with clinical gingival health and homeostasis. Clinical gingival health may be found in a periodontium that is intact, i.e. without clinical attachment loss or bone loss, and on a reduced periodontium in either a non-periodontitis patient (e.g. in patients with some form of gingival recession or following crown lengthening surgery) or in a patient with a history of periodontitis who is currently periodontally stable. Clinical gingival health can be restored following treatment of gingivitis and periodontitis. However, the treated and stable periodontitis patient with current gingival health remains at increased risk of recurrent periodontitis, and accordingly, must be closely monitored. Two broad categories of gingival diseases include non-dental plaque biofilm-induced gingival diseases and dental plaque-induced gingivitis. Non-dental plaque biofilm-induced gingival diseases include a variety of conditions that are not caused by plaque and usually do not resolve following plaque removal. Such lesions may be manifestations of a systemic condition or may be localized to the oral cavity. Dental plaque-induced gingivitis has a variety of clinical signs and symptoms, and both local predisposing factors and systemic modifying factors can affect its extent, severity, and progression. Dental plaque-induced gingivitis may arise on an intact periodontium or on a reduced periodontium in either a non-periodontitis patient or in a currently stable "periodontitis patient" i.e. successfully treated, in whom clinical inflammation has been eliminated (or substantially reduced). A periodontitis patient with gingival inflammation remains a periodontitis patient (Figure 1), and comprehensive risk assessment and management are imperative to ensure early prevention and/or treatment of recurrent/progressive periodontitis. Precision dental medicine defines a patient-centered approach to care, and therefore, creates differences in the way in which a "case" of gingival health or gingivitis is defined for clinical practice as opposed to epidemiologically in population prevalence surveys. Thus, case definitions of gingival health and gingivitis are presented for both purposes. While gingival health and gingivitis have many clinical features, case definitions are primarily predicated on presence or absence of bleeding on probing. Here we classify gingival health and gingival diseases/conditions, along with a summary table of diagnostic features for defining health and gingivitis in various clinical situations.

Photodynamic treatment outcomes of potentially-malignant lesions and malignancies of the head and neck region: A systematic review

AIM

The aim of the present study was to systematically review the efficacy of photodynamic therapy (PDT) in the management of oral potentially-malignant disorders (PMDS) and head and neck squamous cell carcinoma (HNSCC).

METHODS

From 1985 to 2015, PubMed/Medline, Google Scholar, EMBASE, and ISI Web of Knowledge were searched using different combinations of the following key words: PDT, oral precancer, leukoplakia, erythroplakia, erythroleukoplakia, verrucous hyperplasia, oral submucous fibrosis, and HNSCC. Review articles, experimental studies, case reports, commentaries, letters to the editor, unpublished articles, and articles published in languages other than English were excluded.

RESULTS

Twenty-six studies were included in the present study. The number of patients ranged from 2 to 147, with a mean age of 50-67 years. The reported numbers of PMDS and HNSCC ranged between 5 and 225. Photosensitizers used were aminolevulinic acid, meta-tetrahydroxyphenylchlorin, Foscan, hematoporphyrin derivatives, Photofrin, Photosan, and chlorine-e6. Laser wavelength, power density, irradiation duration were 585-652 nm, 50-500 mW/cm² , and 1-143 minutes, respectively. Complete, partial, and no response to PDT was found in 22.58%-100%, 4%-66%, and 0%-38.70% of PMDS, respectively, and 16%-100% of complete response in HNSCC patients.

CONCLUSION

PDT is effective in the management of PMDS and HNSCC.

Implication for second primary cancer from visible oral and oropharyngeal premalignant lesions in betel-nut chewing related oral cancer

BACKGROUND

Visible oral and oropharyngeal premalignant lesions may be used to monitor for a second primary oral cancer. To control for bias, we focused on the visible oral and oropharyngeal premalignant lesions of patients with oral cancer with a positive betel-nut chewing habit. Visible oral and oropharyngeal premalignant lesions that can predict second primary oral cancers were studied.

METHODS

Nine hundred ninety-seven patients with positive betel-nut chewing habits and oral cancer were enrolled in this retrospective cohort study. We analyzed the relevance of their visible oral and oropharyngeal premalignant lesion incidence and relative clinicopathological variables to the development of a second primary oral cancer.

RESULTS

Second primary oral cancer risk was significantly higher in patients with positive visible oral and oropharyngeal premalignant lesions (P < .0001), especially in younger patients (P = .0023; ≤40 years: adjusted odds ratio [OR] 2.66; 40-60 years: adjusted OR 2.61). The heterogeneous leukoplakia was (adjusted OR 2.17) higher than homogeneous leukoplakia.

CONCLUSION

The predictive value and practicality of visible oral and oropharyngeal premalignant lesions make it a potentially valuable marker in follow-ups of patients with a positive betel-nut chewing habit with oral cancer, especially young patients with heterogeneous leukoplakia.

Challenges in predicting which oral mucosal potentially malignant disease will progress to neoplasia

Probably the greatest challenge to those managing patients with oral diseases is the dilemma of attempting to predict which oral erythroplakias, leukoplakias, lichenoid and other potentially malignant mucosal disease (PMD) such as oral submucous fibrosis will progress to neoplasia--notably oral squamous cell carcinoma (OSCC). The paper reviews progress over the past decade and the application to the clinical situation.

Toluidine blue aids in detection of dysplasia and carcinoma in suspicious oral lesions

OBJECTIVES

Accurate clinical identification of 'higher-risk' oral premalignant lesions or 'higher-risk' areas within lesions is important. Assessment methods that predict their presence have great utility.

SUBJECTS AND METHODS

A cross-sectional, observational study enrolled a consecutive sample of consenting patients diagnosed with oral leukoplakia, erythroleukoplakia, or erythroplakia. Medical history, visual oral examination, ViziLite(®) examination, toluidine blue staining (TBlue(®) ), and finally a biopsy were completed in a single clinic visit. Seventy-seven of 100 examined lesions in 43 patients were biopsied. Sensitivity, specificity, and positive and negative predictive values were computed for visual examination, ViziLite(®) , and TBlue(®) using biopsy results as the gold standard.

RESULTS

The sensitivity of TBlue(®) in detecting high-risk lesions (carcinoma in situ or carcinoma) was 94 (71-100, P < 0.0003) and specificity 45 (32-58, P < 0.53), while for carcinoma, sensitivity was 100 (54-100, P < 0.032) and specificity 39 (28-52, P < 0.097). The results of ViziLite(®) testing either by itself or in combination with the information from toluidine blue testing revealed low sensitivity for the detection of high-risk lesions.

CONCLUSIONS

Clinical examination of leukoplakia, erythroplakia, or erythroleukoplakia lesions combined with toluidine blue staining may aid in the identification of severe dysplasia (carcinoma in situ) or carcinoma. This may help in determining whether, when, and where (the site within a lesion) a biopsy should be taken.

Potentially malignant disorders of the oral cavity: current practice and future directions in the clinic and laboratory

Despite commendable progress in the prevention, detection, and treatment of a wide variety of solid tumor types, oral squamous cell carcinoma (OSCC) remains a significant health burden across the globe. OSCC carcinogenesis involves accumulation of genetic alterations that coincide with the multistep malignant transformation of normal oral epithelium. OSCC is often first diagnosed at late stages of the disease (advanced regional disease and/or metastasis). Delayed diagnosis precludes successful treatment and favorable outcomes. In clinical practice, opportunities exist to identify patients with oral potentially malignant disorders (OPMDs), which precede the development of cancer. This review addresses the current status of laboratory and clinical research on OPMDs, with emphasis on leukoplakia and erythroplakia. OSF is also presented, though there is a paucity of published studies on this disorder. We focus on findings that could translate into earlier diagnosis and more efficacious treatment of those lesions with significant malignant potential. We explore how markers of OPMD malignant transformation might be implemented into current diagnostic practice to help clinicians objectively stratify patients into treatment/follow-up groups according to relative risk. We provide an overview of recently concluded and ongoing OPMD chemoprevention trials. We describe laboratory OPMD models that can be used to not only to reveal the genetic and molecular intricacies of oral cancer but also to develop novel screening methods and therapeutic approaches. Finally, we call for targeted screening programs of at-risk populations in order to facilitate diagnosis and treatment of OPMD and early OSCC.