Management of oral leukoplakia: a position paper of the Society of Oral Medicine, Chinese Stomatological Association

Antioxidants for the management of oral leukoplakia: A systematic review of randomized controlled trials

Introduction

Oral leukoplakia (OL) is a potentially malignant disorder characterized by non-scrabble white lesions that may turn into invasive carcinoma if left untreated. Few antioxidant treatments have shown promising results in the regression of lesions and prevention of their progression to carcinoma. We aim to summarize the current evidence on the effectiveness of antioxidants in the management of OL.

Materials and methods

The present systematic review followed PRISMA guidelines and involved a thorough search of three scientific databases: PubMed, Scopus, and Cochrane. We used specific algorithms related to the keywords "antioxidant" and "Oral leukoplakia" to identify randomized controlled trials (RCTs) that have explored the utility of antioxidants in the management of OL. The risk of bias assessment was conducted using the Cochrane risk of bias tool (ROB 2.0), ensuring the reliability of our findings.

Results

Out of 2490 articles retrieved, only thirteen RCTs involving 1147 participants fulfilled the inclusion criteria. Lycopene was found to be the most consistently effective antioxidant, showing significant effectiveness in reducing lesion size, both in oral and topical forms. The trials incorporating other antioxidants, including vitamin A, vitamin C, β-carotene, and curcumin, demonstrated mixed results. Severe heterogeneity was detected in treatment forms, dosage, administration frequency, treatment duration, and follow-up time among all included trials.

Conclusion

Lycopene may play a significant role in the non-surgical management of OL. Future research with large-scale, well-designed, randomized controlled trials with standardized dosing, delivery methods, and outcome measures is mandatory to provide more robust evidence on the available antioxidant therapy for OL.

Effect of the combination of diode laser ablation with photodynamic therapy for oral leukoplakia with epithelial dysplasia: a retrospective study

OBJECTIVE

Photodynamic therapy (PDT) has become a promising treatment option for oral leukoplakia (OLK), but its clinical efficacy and efficiency remain limited. The aim of this study was to assess the effect of combining diode laser ablation with PDT for OLK with epithelial dysplasia.

METHODS

Forty-one patients diagnosed with OLK with epithelial dysplasia (mild, moderate, severe) were recruited in the study. All patients received one session of laser ablation, followed by 1-3 sessions of aminolevulinic acid (ALA) -PDT using a 635 nm laser at 100 mW/cm2 power density at a dosage of 100 J/cm2. The treatment effect was evaluated 1 month after therapy and every 3 months thereafter for a total of 12 months.

RESULTS

All patients responded to the combined therapy. The complete and partial response rates were 61.0% and 39.0%, respectively. Lesion size ≤200 mm2 was associated with complete response (P < .05). During the 12-month follow-up, recurrence occurred in 13 patients. The cumulative rate of malignant transformation was 7.3%.

CONCLUSIONS

Diode laser ablation combined with PDT is an effective and high-efficiency treatment modality for OLK with epithelial dysplasia, particularly for lesion size ≤200 mm2. However, recurrence and malignant transformation still exist after therapy.

Mapping oral medicine (stomatology) and oral and maxillofacial pathology international organizations: a scoping review of global data and historical analysis

OBJECTIVES

To describe the historical evolution and dissemination of the Oral Medicine and Oral and Maxillofacial Pathology international societies and associations across the globe, and to provide insights into their significant contributions toward oral health promotion.

STUDY DESIGN

This review was conducted in accordance with the JBI Scoping Review Methodology Group guidance. The reporting followed the Preferred Reporting Items for Systematic Reviews extension for Scoping Reviews (PRISMA-ScR).

RESULTS

Search strategy was applied to 5 databases (MEDLINE/PubMed, Scopus, Embase, Web of Science, Latin American and Caribbean Health Sciences (LILACS)) and grey literature (Google Scholar, Open Grey and ProQuest), as well as additional sources, such as organization websites. Eighty-nine sources were included in this review. Forty-six professional associations/societies were identified, of which 39 represented a country or geopolitical region, 2 represented continents, 2 represented multinational organizations and 3 multinational study groups.

CONCLUSIONS

Documentation of the historical establishment and development of Oral Medicine and Oral and Maxillofacial Pathology organizations worldwide is limited and describing these processes remains challenging. Analysis of global data reveals heterogeneous development and distribution, resulting in disparities in accessibility and standardization. Further efforts toward oral health promotion should be implemented.

Cucurbitacin B induces ferroptosis in oral leukoplakia via the SLC7A11/mitochondrial oxidative stress pathway

BACKGROUND

Oral leukoplakia (OLK), characterized by abnormal epithelial hyperplasia, is the most common precancerous oral mucosa lesion and is closely related to oxidative stress. Cucurbitacin B (CuB), a tetracyclic triterpenoid molecule derived from plants, has shown promising anti-proliferative and antioxidant effects in preclinical studies. However, whether CuB can play an antiproliferative role in OLK by regulating oxidative stress remains elusive.

PURPOSE

To investigate the role of CuB in inhibiting the malignant progression of oral leukoplakia and to further explore its underlying mechanisms of action.

METHODS

In vitro, the effect of CuB on the proliferation, migration, apoptosis, and cell cycle of OLK cells DOK was detected. The core genes and key pathways of OLK and CuB were analyzed in the transcriptome database, by using immunofluorescence, qRT-PCR, and Western blot to evaluate the expression levels of the ferroptosis markers ROS, GSH, MDA, Fe2+, and marker genes SLC7A11, GPX4, and FTH1. Immunohistochemistry of human tissue was performed to investigate the expression of the SLC7A11. In vivo, the model of OLK was established in C57BL/6 mice and the biosafety of CuB treatment for OLK was further evaluated.

RESULTS

CuB substantially suppressed the proliferation of DOK cells. Bioinformatics analysis showed that the core targets of OLK crossing with CuB include SLC7A11 and that the essential pathways involve ROS and ferroptosis. In vitro experiments indicated that CuB might promote ferroptosis by down-regulating the expression of SLC7A11. We observed a gradual increase in SLC7A11 expression levels during the progression from normal oral mucosa to oral leukoplakia with varying degrees of epithelial dysplasia. In vivo experiments demonstrated that CuB inhibited the malignant progression of OLK by promoting ferroptosis in OLK mice and exhibited a certain level of biosafety.

CONCLUSION

This study demonstrated for the first time that CuB could effectively inhibit the malignant progression of OLK by inducing ferroptosis via activating the SLC7A11/ mitochondrial oxidative stress pathway. These findings indicate that CuB could serve as the lead compound for the future development of anti-oral leukoplakia drugs.

Novel tetrahydrocurcumin integrated mucoadhesive nanocomposite κ-carrageenan/xanthan gum sponges: a strategy for effective local treatment of oral cancerous and precancerous lesions

Oral cancer is one of the leading causes of death worldwide. Oral precancerous lesions (OPL) are the precursors of oral cancer, with varying degrees of progression. Tetrahydrocurcumin (THC) is a major metabolite of curcumin with superior anticancer properties against various types of cancer. However, THC's clinical outcome is limited by its poor aqueous solubility. Herein, we developed novel mucoadhesive biopolymer-based composite sponges for buccal delivery of THC, exploiting nanotechnology and mucoadhesion for efficient prevention and treatment of oral cancer. Firstly, THC-nanocrystals (THC-NC) were formulated and characterized for subsequent loading into mucoadhesive composite sponges. The anticancer activity of THC-NC was assessed on a human tongue squamous carcinoma cell line (SCC-4). Finally, the chemopreventive activity of THC-NC loaded sponges (THC-NC-S) was examined in DMBA-induced hamster OPL. The selected THC-NC exhibited a particle size of 532.68 ± 13.20 nm and a zeta potential of -46.08 ± 1.12 mV. Moreover, THC-NC enhanced the anticancer effect against SCC-4 with an IC50 value of 80 µg/mL. THC-NC-S exhibited good mucoadhesion properties (0.24 ± 0.02 N) with sustained drug release, where 90% of THC was released over 4 days. Furthermore, THC-NC-S had a magnificent potential for maintaining high chemopreventive activity, as demonstrated by significant regression in the dysplasia degree and a decline in cyclin D1 (control: 40.4 ± 12.5, THC-NC-S: 12.07 ± 5.2), culminating in significant amelioration after 25 days of treatment. Conclusively, novel THC-NC-S represent a promising platform for local therapy of OPL, preventing their malignant transformation into cancer.

Comprehensive bioinformatics analysis combined with experimental validation to screen biomarkers for malignant transformation of oral leukoplakia

Oral leukoplakia (OLK) is the most common potentially malignant disorders in the oral cavity. This study aimed to screen the key genes of OLK malignant transformation using the Gene Expression Omnibus (GEO) database and experiments. In this study, the GEO database was employed to screen OLK malignant transformation-related genes, which were subsequently identified with a series of bioinformatic analyses. External validation showed that the model based on LAPTM4B, NR3C1, and COX6A1 had high accuracy in diagnosing OLK malignant transformation. Furthermore, the DMBA-induced potentially malignant disorders and OSCC models in vivo and real-time PCR experiment in vitro further verified the database analysis results. In conclusion, three key genes (LAPTM4B, NR3C1, and COX6A1) were screened as potential biomarkers for the diagnosis and treatment of OLK malignant transformation.

Developmental synergism in the management of oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the oral cavity or lips. The unifying theme of OPMDs is their potential risk for cancer development. Therefore, the primary objective of the management should be to prevent carcinogenesis. Beyond diagnosis, current strategies for the management of OPMDs predominantly include non-surgical and surgical interventions and a "watch-and-see" approach, such as disease monitoring or surveillance, and preventive strategies. Though no optimal clinical treatment has gained universal approval for reducing or preventing malignant development of OPMDs. Therefore, an urgent need exits for improved treatment properties and effective predictive markers for OPMDs treatment. This review aims to outline recent synergism regarding to the management of OPMDs. Developing new technologies and improved application parameters to promote the treatment efficacy and a novel management prescription approach to OPMDs are proposed.

Diode Laser in the Management of Leukoplakia - A Retrospective Study

Introduction

Leukoplakia is among the most common potentially malignant disorders encountered in clinical dental practice. The treatment of leukoplakia includes nonsurgical and surgical management. The surgical treatment includes excision, electrocauterisation, laser surgery or cryosurgery. This retrospective study aimed to analyse the efficacy of diode lasers in the management of leukoplakia.

Methods

The sample consists of 56 cases with 77 leukoplakia sites treated with diode laser between January 2018 and December 2020 with a minimum of six months follow-up. For each patient, personal data was collected along with site of lesions, leukoplakia phase, type of treatment performed (laser ablation or laser excision), side effects, recurrences and malignant transformation. Inferential statistical analysis was then conducted.

Results

After applying exclusion criteria, 56 cases with 77 leukoplakia sites were included in this study. Males aged >45 years were predominantly affected. Homogeneous leukoplakia (48.1%) was the most common phase. Recurrences were noted in 19.48% of the cases. Compared to laser excision, laser ablation had more recurrences. Gingival lesions showed a higher recurrence rate than other sites in the oral cavity. None of the cases showed malignant transformation.

Discussion

Laser offers many advantages over other conventional methods including lesser postoperative pain and swelling, bloodless dry operating field and increased patient comfort and requires minimal local anaesthesia. The study concluded that diode laser is an effective surgical treatment modality for treating leukoplakia. Furthermore, the laser excision technique was found to be superior to laser ablation due to lesser recurrence.