Interventional laser surgery: an effective surgical and diagnostic tool in oral precancer management

Oral Pre-malignancy: An Update on Novel Therapeutic Approaches

PURPOSE OF REVIEW

This review aims to provide a comprehensive overview of the current advances in managing and preventing progression of oral potentially malignant disorders (OPMDs), focusing on their histological and clinicopathological features, and management.

RECENT FINDINGS

Recent studies, including a multicenter cross-sectional study, have identified oral leukoplakia as the most prevalent form of OPMD, comprising over half of the cases examined. Advances in histological grading, specifically the World Health Organization's three-tier system (mild, moderate, and severe dysplasia), have significantly enhanced the accuracy of risk assessment for malignant transformation. Additionally, treatments such as surgical interventions, photodynamic therapy, and chemopreventive and molecularly targeted agents are being evaluated for their safety and efficacy as well as, immune checkpoint inhibitors being evaluated as potential preventive strategies to halt the progression of OPMDs. The management of OPMDs remains challenging due to the lack of standardized screening protocols and varied clinical management approaches. Despite this, recent advancements in diagnostic grading and therapeutic interventions provide a framework for improved treatment outcomes. Continued research into the molecular and cellular mechanisms driving development and progression of OPMDs and innovative treatment trials are essential to optimize strategies that prevent malignant progression and thereby reduce the global health burden of oral cancer.

CO2 LASER versus Blade Scalpel Surgery in the Management of Nasopharyngeal Masses in Dogs

We aimed to compare surgical time, bleeding level, patient pain level, healing period, scar tissue, relapse of the initial process and complications in patients with nasopharyngeal oncological masses undergoing surgery using a scalpel blade versus a CO2 surgical laser. This is a clinical prospective study comprising surgical work in the nasopharynx area. A sample of 12 inpatients dogs (N = 12) of both genders underwent a surgical excision of nasopharyngeal masses with a scalpel blade (GS n = 6) and CO2 surgical laser (GL n = 6). An Aesculigth CO2 surgical laser-Vetscalpel® model with a superpulse mode, 12 W of power, and a multi-focus pen was used. Statistically significant differences were registered for a p-value of < 0.05. Variations were noted between both groups (GS and GL) concerning surgery time (p = 0.038), first meal time (p = 0.013), pain level (p = 0.003), and healing time (p = 0.014), with the GL group presenting lower values. GL exhibited only one relapse case, with the elapsed time being more than double that of the GS group. Surgical and healing times were shorter in the GL group, and pain levels were lower, with the GL group also demonstrating less scar tissue than the GS group, along with a lower relapse rate. Nasopharynx surgical exposure with precision via the soft palate using the CO2 laser has facilitated successful treatment of regional masses without discomfort and complications, compared to conventional blade scalpel procedures.

Relevant parameters for laser surgery of soft tissue

In recent years, the laser has become an important tool in hospitals. Laser surgery in particular has many advantages. However, there is still a lack of the understanding of the influence of the relevant parameters for laser surgery. In order to fill this gap, the parameters pulse frequency, use of an exhaustion system, air cooling, laser power, laser scan speed, laser line energy and waiting time between cuts were analysed by ANOVA using inter-animal variation as a benchmark. The quality of the cuts was quantized by a previously published scoring system. A total of 1710 cuts were performed with a [Formula: see text] laser. Of the parameters investigated, laser power and scan speed have the strongest influence. Only the right combination of these two parameters allows good results. Other effects, such as the use of pulsed or continuous wave (CW) laser operation, or air cooling, show a small or negligible influence. By modulating only the laser power and scan speed, an almost perfect cut can be achieved with a [Formula: see text] laser, regardless of the external cooling used or the laser pulse duration or repetition rate from CW to nanosecond pulses.

Importance of the vaporization margin during CO2 laser treatment of oral leukoplakia: A survival study

OBJECTIVES

The main purpose of this study was to assess the response of oral leukoplakia to CO2 laser vaporization treatment, as well as determining possible factors that may affect recurrence of lesions.

MATERIALS AND METHODS

A retrospective study was conducted, in which the medical records of patients who had been clinically and histologically diagnosed with oral leukoplakia and treated with CO2 laser between 1996 and 2019 at the Oral Medicine Teaching Unit of the Faculty of Dentistry of the University of Santiago de Compostela were reviewed.

RESULTS

Fifty-eight patients were included: 36 female and 22 male subjects, with a mean age of 63.7 years old (SD ±13.1). The average follow-up time was 57.5 months (SD ±57.9). A relapse rate of 52.6% was determined. Of all the studied variables, the margin was the only one for which a statistically significant association with recurrence of lesions was demonstrated (p < 0.05).

CONCLUSION

The vaporization of lesions using CO2 laser with a safety margin of at least 3 mm from the clinical limits of OL is a key factor in preventing recurrence.

Gold nanorod-based multiplex bioanalytical assay for the detection of CYFRA 21-1 and CA-125: towards oral cancer diagnostics

The study emphasizes the application of gold nanorods (GNRs) with different aspect ratios (ARs) for the development of multiplex assay for oral cancer detection. The tunable optical properties of the GNRs that rely on the geometrical alterations of the nanostructure and the corresponding change in the refractive indices of the local environment form the basis of the label-free biosensing mechanism. In the present work, two GNRs with AR 2.1 and AR 3.9 exhibiting LSPR at 620 and 775 nm were used for sensing oral cancer biomarkers (Cyfra 21-1 and CA-125). Clinically relevant salivary concentrations of CYFRA 21-1 and CA-125 were taken into consideration for designing the assay range. Herein, the antibodies against Cyfra 21-1 and CA-125 have been employed as biospecific probes to functionalize the GNRs with different ARs. Molecular interactions that induce a spectral shift of distinct plasmon band maxima facilitated quantitative assessment of the target analyte. The GNR bioprobe employed for sensing Cyfra 21-1 had a wide linear detection range of 0.496-48.4 ng mL^-1 with a detection limit as low as 0.84 ng mL^-1 and for CA-125 the detection range was 5-320 U mL^-1 with a detection limit of 1.6 U mL^-1. The individual GNR bioprobe also showed high specificity against several interferents. For multiplexed biosensing, the plasmon spectra of the GNR bioprobe mixture showed distinct responses upon binding of single and dual targets in the sample mixture and/or artificial saliva. The quantitative data from the developed method are of high clinical significance that can aid in the understanding of clinicopathological advancements in oral cancer at an early stage. This simple yet novel nanosized optical transducer technology can be further converted into miniaturized biochips and can be deployed in clinics as a nanoparticle-based point-of-care diagnostic adjunct.

Development and evaluation of a scoring system for assessing incisions in laser surgery

The idea of laser surgery is nearly as old as the laser itself. From the first trials to modern laser surgery systems, it was and is the aim to selectively cut the tissue in the focus spot without causing harm to surrounding structures. This is only possible when the correct parameters for the surgical laser are chosen. Usually, this is done by parameter studies. However, the concrete evaluation scheme often differs between groups and more precise approaches require staining and microscopic evaluation. To overcome these issues, a macroscopic scoring system is presented and evaluated. It can be shown that the scoring system works well and, thus, a laser cut can be evaluated within a few seconds. At the same time, the whole cutting front is taken into account. The presented scoring system is evaluated by the intra class correlation (ICC). The final agreement between different raters is more than 0.7. Therefore, the scoring system can be used to optimize and evaluate the cutting process and it should be suitable for comparing the results between different groups. Definitely, it can be applied for scoring within a group to enable e.g., a profound statistical analysis for a parameter study.

Critical update, systematic review, and meta-analysis of oral erythroplakia as an oral potentially malignant disorder

Background

Oral erythroplakia has been classically considered as the potentially malignant disorder with the highest rate of malignant development into squamous cell carcinoma. This critical systematic review and meta‐analysis aim to estimate the malignant development rate of oral erythroplakia and identify the associated risk factors.

Methods

We performed a bibliographic search in PubMed, Scopus, Web of Science, Embase, and LILACS, with keywords “erythroplakia,” “erythroplasia,” “malignant transformation,” “malignant development,” “malignization,” “carcinogenesis,” “oral cancer,” “oral squamous cell carcinoma,” “mouth neoplasm,” and “prognosis.” Meta‐analysis was conducted using a random‐effects model.

Results

Ten observational studies with 441 patients met the inclusion criteria, whose mean malignant development rate was 12.7% and with a mean follow‐up period of patients of 6.66 years. In the initial biopsy, 42.8% of oral erythroplakia were already squamous cell carcinoma. The buccal mucosa was the most frequent location of oral erythroplakia, but the floor of the mouth was the most common site of malignant development. All patients who underwent malignant development showed epithelial dysplasia on the initial diagnostic biopsy.

Conclusion

Overall malignant development rate of OE in the meta‐analysis was 19.9%. We could not associate any specific clinicopathological feature with the malignant development. The presence of epithelial dysplasia in the initial biopsy remains the worst prognostic factor. Further observational studies on OE are needed, with well‐established diagnostic criteria and good clinical follow‐up, in order to identify the true risk of malignant development of oral erythroplakia and the related risk factors.

Recurrence and malignant transformation rates of high grade oral epithelial dysplasia over a 10 year follow up period and the influence of surgical intervention, size of excision biopsy and marginal clearance in a UK regional maxillofacial surgery unit

OBJECTIVES

To determine the overall recurrence rate (RR) and malignant transformation rate (MTR) of high grade oral mucosal epithelial dysplasias (HGOED).

MATERIALS & METHODS

A clinicopathological review of records of patients diagnosed with a unifocal HGOED between 2004 and 2016 on incisional biopsy who then underwent excision. The mean duration of follow-up was 47.7 months (±29.9 SD).

RESULTS

Full demographic, historical and histopathological data were available for 120 patients. Six were lost to follow-up after excisional biopsy. Invasive squamous cell carcinoma (SCC) was present in 19 (18.3%) excisions. HGOED affected the lateral and ventral tongue in 58% of patients. Fourteen (11.7%) were not treated surgically but kept under surveillance. The overall RR was 34.7% (33 patients) and MTR 17.8% (17 patients). Four of the 14 (28.6%) patients who had not had the HGOED excised developed SCC, by contrast to the 13 of the 106 (12.3%) who had been treated. RR was significantly associated with positive excision margins (p = 0.007; OR = 3.6) and a clinical presentation of erythroplakia (p = 0.023; OR = 1.5). MTR was significantly associated with age (p = 0.034), clinical appearance (p = 0.030), site (p = 0.007), treatment received (p = 0.012) and positive excision margins (p = 0.007). The mean time for recurrence to develop was 62 months (±31.5 SD) (range 22-144 months), that for malignant transformation was 50 months (±32.5 SD) (range 8-97 months).

CONCLUSION

Patients with HGOED require follow-up for at least 10 years after treatment. Younger age, homogeneous clinical appearance, complete excision, a larger excision specimen and clear margins all improve prognosis.

Patient-reported pain after surgical removal of leukoplakia - an observational 1-year follow-up study

OBJECTIVE

Oral leukoplakia (OL) presents as a white lesion of the oral mucosa and is not typically associated with the sensation of pain. OL should be surgically removed when possible because it is considered a potentially malignant oral disorder (PMOD). This study assessed the pain sensations experienced by patients in association with the occurrence and surgical treatment of OL.

METHODS

Inclusion criteria were: a clinical diagnosis of OL; biopsy excision; and observation for at least 12 months in the ORA-LEU-CAN study. At the first visit, all the patients were asked about the occurrence of symptoms within the lesion. Ninety-four subjects were assessed over a period of 1 year. All patients underwent complete removal of OL. The patient cohort was divided into three sub-groups: (i) no pain before excision and at the 1-year follow-up; (ii) pain before excision; and (iii) pain at the 1-year follow-up.

RESULTS

Overall, pain was reported by 21.3% of the patients at the study start whereas 13.8% of the patients reported pain 1 year after surgical treatment. Patient-reported pain from the lesion at study inclusion was significantly associated with lesions found on the lateral side of the tongue (p=.002). Pain reported by patients one year after surgery was significantly related to female gender (p=.038) and the presence of epithelial cell dysplasia (p=.022).

CONCLUSION

We conclude that surgical removal of OL results in a low risk of long-term post-surgical pain. However, OL located on the lateral side of the tongue and in OL with dysplasia are more likely to be associated with pain.

Low-fluence and low-density CO2 laser: histological analysis of collagen fiber changes in skin and its clinical repercussions in photorejuvenation

This study refers to clinical and histologic analysis of effects on photorejuvenation after one single treatment of fractional CO2 laser with low fluence and low density. To analyze histologically the quantitative variation of collagen fibers type I and III, elastic fibers, and epidermal thickness on D84, besides clinical evaluation of amount, length, thickness, and depth of periocular wrinkles during the same period. This is an open, prospective, interventional study. There were 40 healthy female with age between 35 and 65 years. Twenty-six participants were randomly selected for D0 and D84 biopsy. A single session of fractional CO2 laser was done in the hole face, using a 800-µm tip, 5% density, and 10 mJ fluence with a single pass. On D0, D42, and D84, a clinical comparative analysis of amount, length, depth, and thickness of periocular wrinkles has been done. On histological analysis, a comparative quantitative evaluation of collagen fibers type I and III, elastic fibers, and epidermal thickness has been done on D0 and D84. The results of this study denoted a significant clinical improvement of amount (- 32.17%; p < 0.0001), thickness (- 33%; p < 0.0001), lenght (- 35.84%; p < 0.0001), and depth of periocular wrinkles (- 32.46%; p < 0.0001). A significant increase in the amount of collagen fibers type III was observed on D84 (+ 60.67%; p = 0.0013). Collagen fibers type I and elastic fibers did not have the same result, with a nonsignificant increase (+ 8.31%; p = 0.3820) and a decrease (- 12.4%; p = 0.0585) respectively. Epidermal thickness has a tendency to significant variation (p = 0.05553). The results demonstrate that fractional CO2 laser with low fluence and low density is a safe and efficient option for photorejuvenation of the face.

Effect of Fluorescence Visualization-Guided Surgery on Local Recurrence of Oral Squamous Cell Carcinoma: A Randomized Clinical Trial

Importance

High local recurrence rates with aggressive disease remain the main concern in oral cancer survival. Use of a translational device using fluorescence visualization (FV) approved by the US Food and Drug Administration and Health Canada, has shown a marked reduction in the 3-year local recurrence rate of high-grade oral lesions in a single-center observational study.

Objective

To determine whether FV- guided surgery can improve local control rates in the treatment of in situ or T1 to T2 category oral squamous cell carcinoma (OSCC).

Design, Setting, and Participants

A multicenter randomized clinical trial was conducted in a surgical setting. A total of 457 patients were enrolled between January 18, 2010, and April 30, 2015. Data analysis of the intention-to-treat population was performed from April 3, 2019, to March 20, 2020. Patients with histologically confirmed high-grade dysplasia/carcinoma in situ or T1 to T2 category OSCC were randomized to receive traditional peroral surgery or FV-guided surgery.

Intervention

Fluorescence visualization during surgery.

Main Outcomes and Measures

The primary outcome was local recurrence of OSCC. Secondary outcomes were failure of the first-pass margin, defined as a histologically confirmed positive margin for severe dysplasia or greater histologic change of the main specimen (ie, not the margins taken from the resection bed), regional or distant metastasis, and death due to disease.

Results

Of the 457 patients enrolled in the study, 443 patients (264 [59.6%] men; mean [SD] age, 61.5 [13.3] years) completed the randomized treatment: 227 FV-guided and 216 non-FV guided surgery. The median follow-up was 52 (range, 0.29-90.8) months. In total, 45 patients (10.2%) experienced local recurrence. The 3-year local recurrence rate was 9.4% in the FV-guided group and 7.2% in the non-FV group (difference, 2.2%; 95% CI, -3.2% to 7.4%). Other similarities between the FV vs non-FV groups included failure of first-pass margin (68/227 [30.0%]) vs 65/216 [30.1%]), regional failure (39/227 [17.2%] vs 37/216 [17.1%]), disease-specific survival (23/227 [10.1%] vs 19/26 [8.8%]), and overall survival (41/227 [18.1%] vs 38/216 [17.6%]) were also similar between groups. No adverse events were judged to be related to the intervention.

Conclusions and Relevance

In this randomized clinical trial, FV-guided surgery did not improve local control rates in the treatment of patients with in situ or T1 to T2 category oral cancer. Under a controlled environment, FV-guided surgery did not have an evident effect in reduction of local recurrence for localized OSCC. This result suggests that attention be directed to strategies other than improving definitions of nonapparent disease at clinical margins to identify the sources of local recurrence.

Trial Registration

ClinicalTrial.gov Identifier: NCT01039298.

In Vitro Cytological Responses against Laser Photobiomodulation for Periodontal Regeneration

Periodontal disease is a chronic inflammatory disease caused by periodontal bacteria. Recently, periodontal phototherapy, treatment using various types of lasers, has attracted attention. Photobiomodulation, the biological effect of low-power laser irradiation, has been widely studied. Although many types of lasers are applied in periodontal phototherapy, molecular biological effects of laser irradiation on cells in periodontal tissues are unclear. Here, we have summarized the molecular biological effects of diode, Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO₂ lasers irradiation on cells in periodontal tissues. Photobiomodulation by laser irradiation enhanced cell proliferation and calcification in osteoblasts with altering gene expression. Positive effects were observed in fibroblasts on the proliferation, migration, and secretion of chemokines/cytokines. Laser irradiation suppressed gene expression related to inflammation in osteoblasts, fibroblasts, human periodontal ligament cells (hPDLCs), and endothelial cells. Furthermore, recent studies have revealed that laser irradiation affects cell differentiation in hPDLCs and stem cells. Additionally, some studies have also investigated the effects of laser irradiation on endothelial cells, cementoblasts, epithelial cells, osteoclasts, and osteocytes. The appropriate irradiation power was different for each laser apparatus and targeted cells. Thus, through this review, we tried to shed light on basic research that would ultimately lead to clinical application of periodontal phototherapy in the future.

The "Peter Principle" revisited-Reflections on science, surgery and research

Revisiting the eponymous "Peter Principle," in this article the author reflects upon a professional lifetime as a clinician, surgeon and researcher, and summarises his efforts to improve contemporary understanding of oral cancer development, refine diagnostic procedure and facilitate efficacious, early treatment intervention to halt the process of carcinogenesis. The author reviews the principles underpinning effective translational research. Utilising his own work in oral epithelial cell science, interventional surgery and potentially malignant disorder patient management and surveillance, a number of significant advances in our knowledge base and their specific clinical application and potential impact are discussed. Research remains an active and ongoing process, however, and the author believes it essential for future relevance that hypotheses should always be initiated, led and mentored by experienced clinical practitioners.

Saponin Facilitates Anti-Robo1 Immunotoxin Cytotoxic Effects on Maxillary Sinus Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide. The standard treatment of surgery, chemotherapy, and radiotherapy can result in long-term complications which lower the patient's quality of life, such as eating disorders, speech problems, and disfiguring or otherwise untoward cosmetic issues. Antibody therapy against cancer-specific antigens is advantageous in terms of its lesser side effects achieved by its greater specificity, though the antitumor activity is still usually not enough to obtain a complete cure. Robo1, an axon guidance receptor, has received considerable attention as a possible drug target in various cancers. We have shown previously the enhanced cytotoxic effects of saporin-conjugated anti-Robo1 immunotoxin (IT-Robo1) on the HNSCC cell line HSQ-89 in combination with a photochemical internalization technique. Considering the light source, which has only limited tissue penetrance, we examined the drug internalization effect of saponin. Treatment with saponin facilitated significant cytotoxic effects of IT-Robo1 on HSQ-89 cells. Saponin exerts its own nonspecific cytotoxicity, which may cover the actual extent of the internalization effect. We thus examined whether a flashed treatment with saponin exerted a significant specific cytotoxic effect on cancer cells. The combination of an immunotoxin with saponin also exhibited a significant tumor-suppressive effect on mice HSQ-19 xenografts. These results suggest the utility of saponin treatment as an enhancer of immunotoxin treatment in cancer.

EVALUATION OF INNOVATIVE DIGITALLY CONTROLLED ER:YAG LASER IN SURGICAL TREATMENT OF ORAL LEUKOPLAKIA - A PRELIMINARY STUDY

The use of lasers for treatment of oral leukoplakia has gained a lot of interest in the past years, however, data on the use of Er:YAG laser are scarce. The aim of this study was to compare the efficacy of Er:YAG laser and 1% topical isotretinoin in the treatment of 27 oral leukoplakia patients. Er:YAG laser (LightWalker AT, Fotona, Slovenia) was used in 27 patients with 27 leukoplakia lesions. Postoperative pain was assessed by use of visual analog scale (VAS), and the impact of laser treatment on the quality of life was assessed by the OHIP-14 questionnaire (Croatian version). Control group consisted of the same 27 patients previously treated with 1% topical isotretionin three times a day during the period of one year. No improvement in the size of leukoplakia lesions was observed after treatment with topical isotretinoin. There were significant differences between men and women according to leukoplakia localization, number of laser sessions and VAS (p<0.05). At follow-up after six months and one year, there was no recurrence of lesions. Er:YAG laser is a successful treatment for oral leukoplakia. Topical isotretionin treatment is unsuccessful in patients with oral leukoplakia.

The"Newcastle Nomogram"-Statistical modelling predicts malignant transformation in potentially malignant disorders

BACKGROUND

Nomograms are graphical calculating devices used to predict risk of malignant transformation (MT) or response to treatment during cancer management. To date, a nomogram has not been used to predict clinical outcome during oral potentially malignant disorder (PMD) treatment. The aim of this study was to create a nomogram for use by clinicians to predict the probability of MT, thereby facilitating accurate assessment of risk and objective decision-making during individual patient management.

METHODS

Clinico-pathological data from a previously treated cohort of 590 newly presenting PMD patients were reviewed and clinical outcomes categorized as disease free, persistent PMD or MT. Multiple logistic regression was used to predict the probability of MT in the cohort using age, gender, lesion type, site and incision biopsy histopathological diagnoses. Internal validation and calibration of the model was performed using the bootstrap method (n = 1000), and bias-corrected indices of model performance were computed.

RESULTS

Potentially malignant disorders were predominantly leukoplakias (79%), presenting most frequently at floor of mouth and lateral tongue sites (51%); 99 patients (17%) developed oral squamous cell carcinoma during the study period. The nomogram performed well when MT predictions were compared with patient outcome data, demonstrating good bias-corrected discrimination and calibration (D_xy  = 0.58; C = 0.790), with a sensitivity of 87% and specificity 63%, and a positive predictive value of 32% and negative predictive value 96%.

CONCLUSION

The "Newcastle Nomogram" has been developed to predict the probability of MT in PMD, based on an internally validated statistical model. Based upon readily available and patient-specific clinico-pathological data, it provides clinicians with a pragmatic diagrammatic aid for clinical decision-making during diagnosis and management of PMD.

Tumors of the oral cavity: CO2 laser management

BACKGROUND

Cancer of the oral cavity combined with oropharyngeal cancer is the sixth leading cause of death for cancer worldwide. Surgery remains the standard treatment for this disease in early clinical and locally advanced stages. Numerous studies have shown that laser management is useful for premalignant lesions in the oral cavity; however, there is no conclusive evidence that its use is appropriate in cancer of the oral cavity and that results are comparable with traditional surgery. The objective of this study is to determine cancer control after wide local resection with CO2 laser for oral malignant neoplasms.

MATERIAL AND METHODS

Retrospective study in patients with tumors of the oral cavity who were considered for surgical resection with CO2 laser from January 2006-December 2015. Demographic data, treatment modalities, histopathological diagnosis and clinical stage variables were obtained. All resections were done with the use of the microspot. Patients with cancer of the tongue were not included because a specific protocol for these patients does exist in our institution.

RESULTS

There were twenty patients, 10 male and 10 female with a average age of 58 years (range: 20-92 years). Mean age was 53.5 years for females and 63 years for males. Twelve (60%) patients are alive and disease free and four (20%) were lost free of disease.

CONCLUSIONS

CO2 laser is an acceptable surgical method for the management of small lesions in the oral cavity. We cannot rule out that small lesions of the oral cavity with positive neck could be managed in this manner, adding treatment to the neck, producing an adequate local regional control. However, this hypothesis requires additional studies.

IL-8 promotes HNSCC progression on CXCR1/2-meidated NOD1/RIP2 signaling pathway

NOD1 (nucleotide-binding oligomerization domain 1) is overexpressed in head and neck squamous cell carcinoma (HNSCC) cells, as is IL-8 in cancer cells. However, the mechanism of the IL-8-mediated overexpression of NOD in HNSCC not been identified. This study determines whether IL-8 promotes tumor progression via the NOD signaling pathway in HNSCC. Higher IL-8, NOD1 and receptor-interacting protein kinase (RIP2) expressions were observed in HNSCC tissue than in non-cancerous matched tissue (NCMT), whereas NOD2 was weakly expressed. Furthermore, IL-8 stimulated the proliferation of HNSCC cells (SCC4, SCC9 and SCC25) but not dysplastic oral mucosa DOK cells. Exposure to IL-8 increased the clonogenicity of HNSCC cells. IL-8 siRNA inhibited cell proliferation and cell colony formation, suggesting that IL-8 is involved in HNSCC cancer progression. The expressions of CXCR1 and CXCR2 were higher in HNSCC tissue than in NCMT. HNSCC cells that were exposed to IL-8 exhibited higher expression of CXCR1/2 than did controls. The blocking of IL-8 by siRNA reduced CXCR1/2 expression in HNSCC cells, suggesting that the cancer progression of HNSCC cells that is induced by IL-8 depends on CXCR1/2. Additionally, IL-8 is associated with increased NOD1 and RIP2 expression and reduced NOD2 expression in three types of HNSCC cells. The blocking of IL-8 by siRNA reduces IL-8, NOD1 and RIP2 expressions in HNSCC cells, but not the level of NOD2. These results suggest that IL-8 has an important role in HNSCC progression via a CXCR1/2-meidated NOD1/RIP2 signaling pathway.

Outcome of CO2 laser vaporization for oral potentially malignant disorders treatment

Background

Oral cancer is a public health issue worldwide. Oral potentially malignant disorders (OMPDs) are lesions of the oral mucosa that are predisposed to malignant transformation. The mainstay of OMPDs treatment around the world is now the carbon dioxide (CO2) laser but the reported recurrence and malignant transformation rates vary widely in the literature. We aimed to estimate the recurrence and the malignant transformation rates of OPMDs treated with CO2 laser at the University Hospital of Bordeaux, in France, from 2010 to 2014, and to identify associated factors with recurrence or malignant transformation.

Material and Methods

We conducted a retrospective study in patients with a minimum follow-up of 12 months. Collected variables included characteristics of the patients (gender, age, alcohol and tobacco consumption, previous diagnosis of graft-versus-host disease, previous treatments for OPMD or for upper aerodigestive tract cancers and human immunodeficiency virus infection), characteristics of the lesions (form, colour, size, location, degree of dysplasia), laser treatment outcome (complications, recurrence, malignant transformation).

Results

Twenty-five patients were included. Mean follow-up was 28.9 months. Recurrence was observed in 11 patients (44%). Annual recurrence rate was 18.3% and annual malignant transformation rate was 1.7%. Hyperplasia without dysplasia was the only factor found to be statistically associated with recurrence.

Conclusions

Our results suggest that OMPDs treated by CO2 laser vaporization have high recurrence rates, particularly those presenting hyperplasia. A standardized definition of recurrence would be necessary for inter-study comparisons. Long-term follow-up is recommended in order to detect and treat squamous cell carcinoma in its early stages.

Key words:CO2 lasers, precancerous conditions, malignant transformation, oral cancer, recurrence.

An actionable test using loss of heterozygosity in identifying high-risk oral premalignant lesions

OBJECTIVES

To develop an actionable test using fluorescence capillary electrophoresis (FCE) to assess loss of heterozygosity (LOH) of histologically similar low-grade lesions (LGLs) to identify high-risk lesions for oral cancer progression.

STUDY DESIGN

To determine the cutoffs of LOH, the FCE results of 52 surgical margin samples were used to compare with the existing LOH results from the previously validated 32 P-GE approach. Using the developed FCE workflow, an independent set of 102 LGLs with known progression status was used to determine the LOH molecular risk (MR) patterns and associated risk of progression.

RESULTS

Using 65% cutoff LOH-FCE, the agreement of LOH-32 P-GE had an average of 82.3% (76.8-87.8). Compared with nonprogressors (n = 61), anatomic site and MR patterns (LOH at 9 p21, 3 p14, or 17 p13) were independent risk factors. High-risk profile of tongue and MR3 (LOH at 9 p21 and/or 3 p14 and 17 p13) was significantly associated with progression (hazard ratio [HR] 6.7; 95% confidence interval [CI] 2.6-17.6) with specificity of 98.4% at identifying progressors.

CONCLUSIONS

We have developed an objective test using LOH to stratify the risk of LGLs. With further validation, it can be used in the clinical settings to provide clinicians additional information guiding the management of these lesions.

Treatment resistance in potentially malignant disorders-'Nature' or 'Nurture'…?

BACKGROUND

Contemporary potentially malignant disorder management is based upon provisional histological diagnosis followed by interventional surgery to excise or ablate 'high-risk' mucosal lesions. Although the majority of patients achieve disease-free status post-treatment, others develop further or persistent disease unresponsive to intervention.

METHODS

A detailed, retrospective clinico-pathological review of treatment resistant potentially malignant lesions, from a 590 patient cohort treated by CO₂ laser surgery and followed for a mean of 7.3 years, was undertaken. Clinical outcome was determined at study census date (31 December 2014).

RESULTS

A total of 87 patients (15%) exhibited PMD disease resistant to treatment: 34 (6%) became disease free following further treatment, whilst 53 (9%) had persistent disease despite intervention. Disease-free patients were younger, changed lesion appearance from erythroleukoplakia to leukoplakia (P = .004), developed further lesions at new sites, demonstrated reduction in dysplasia severity with time and required multiple treatments to achieve disease-free status (P = .0005). In contrast, persistent disease patients were older, male, often presented with proliferative verrucous leukoplakia (PVL) on gingival and alveolar sites, displayed less severe dysplasia initially and underwent laser ablation rather than excision (P = .027).

CONCLUSION

Despite clinico-pathological profiling of treatment resistant patients, the precise inter-relationship between the inherent nature of potentially malignant disease and the external influence of treatment intervention remains obscure.

Profiling cancer risk in oral potentially malignant disorders-A patient cohort study

BACKGROUND

Oral potentially malignant disorders harbour variable and unpredictable risk for squamous carcinoma development. Whilst current management strategies utilise histopathological diagnoses, dysplasia grading and targeted intervention for "high-risk" lesions, clinicians are unable to predict malignant potential.

METHODS

Detailed, retrospective clinico-pathological analysis of potentially malignant lesions undergoing malignant transformation, from a 590 patient cohort treated by interventional laser surgery and followed for a mean of 7.3 years, was undertaken. Clinical outcome was documented at study census date (31 December 2014).

RESULTS

A total of 99 patients (16.8%) developed cancer: 71 (12%) seen "unexpectedly" upon excision and 28 (4.8%) progressing to malignancy at a median of 87.3 months post-surgery. Thirty "unexpected" excisions were micro-invasive (42.3%) arising primarily in severely dysplastic precursors (75%) at ventro-lateral tongue and floor of mouth sites (54.5%); 1 patient (1.4%) had a cancer-related death, whilst 58 (81.7%) were disease free. A total of 19 of 28 "progressive" cancers (67.9%) arose at new sites, with erythroleukoplakia a significant predictor of malignancy (P = .0019). Nine (32.1%) developed at the same precursor site, with 6 (77.7%) on the ventro-lateral tongue and floor of mouth. Three (10.7%) were micro-invasive, 9 patients (32.1%) died from metastatic disease and 12 (42.9%) were disease free (P < .001).

CONCLUSION

Squamous carcinoma may arise at the site of a precursor lesion as transformation or new-site development via field cancerisation. Whilst interventional surgery facilitates early diagnosis and treatment of occult disease, thus reducing risk from same-site transformation, new-site cancer is a significant long-term risk for patients with potentially malignant disorder.

Efficacy of oral brush biopsy in potentially malignant disorder management

BACKGROUND

Oral potentially malignant disorders (PMD) harbour unpredictable risk for squamous cell carcinoma development. Current management requires tissue biopsy for histopathology characterisation, dysplasia grading and targeted intervention to "high-risk" lesions, although evidence-based guidelines are limited and diagnoses subjective. This study investigated the use of adjunctive oral brush biopsy techniques during the management of PMD in a UK hospital population.

METHODS

Retrospective review of a 310 PMD patient cohort presenting to Maxillofacial Surgery in Newcastle upon Tyne with new, single-site lesions between December 2009 and May 2014. Patients underwent Orcellex^® brush biopsy and liquid-based cytology examination in addition to conventional biopsy techniques, with management proceeding along established care pathways. Patient demographics, cytology data, most significant histopathology diagnoses and clinical outcome were all documented at the study census date (31.12.15).

RESULTS

A total of 170 male & 140 female patients (age range 18-91 years), exhibiting primarily leukoplakia (86.5%) at floor of mouth and ventrolateral tongue sites (44.9%), were identified. Management comprised: observation (49.7%), laser surgery (44.9%), antifungal treatment (3.5%) and Head & Neck clinic referral following cancer diagnosis (1.9%). Clinical outcomes were as follows: disease free (51.3%), persistent PMD (42.3%) and malignant transformation (6.4%). Histology and cytology diagnoses strongly correlated (r = .305). Treatment modality, lesion site, histology and cytology diagnoses were the best predictors of clinical outcome.

CONCLUSIONS

Orcellex^® brush cytology provides reliable diagnoses consistent with conventional histopathology and offers less invasive, adjunctive assessment appropriate for long-term monitoring of patients in specialist clinics.

Type of surgical treatment and recurrence of oral leukoplakia: A retrospective clinical study

BACKGROUND

Oral leukoplakia (OL) is the most typical potentially malignant disorder of the oral mucosa. We aimed to evaluate the clinical outcome of oral leukoplakia treated with several types of lasers and with the use of quantic molecular resonance (QMR) lancet, in terms of recurrence rate.

MATERIAL AND METHODS

Eighty-seven previously untreated OL (52 occurring in females and 35 in males, mean age of 59.4 ± 13.9 years) were consecutively submitted to surgical treatment at University Hospital of Parma, Italy, and Hospital de Valongo, Portugal, (1999 to 2012). Interventions were subclassified into 5 groups according to the instrument used for the surgical removal of OL (cold blade - 17; Nd:YAG 1064nm laser - 14; Er:YAG 2940nm laser - 33; CO2 10600nm laser - 15; and QMR scalpel - 8). The mean follow-up period after treatment was 21.6 months (range 1-151 months). The outcome of treatment was scored through the same clinical protocol in the two participating units. Statistical analysis were carried by univariate analysis using chi-square test (or Pearson's test when appropriate).

RESULTS

Recurrences were observed in 24 cases of OL (27.6%). Malignant transformation occurred in one patient (1.1%) after a period of 35 months. Statistical comparison of the 5 surgical treatment modalities showed no differences in clinical outcomes nor in the recurrence rate of OL. However, when Er:YAG laser group was compared with traditional scalpel, a significantly better outcome in cases treated with Er:YAG laser (P = 0.015) was highlighted.

CONCLUSIONS

Our results suggests that Er:YAG laser could be a promising option for the treatment of OL.

Factors affecting Clinical Outcomes after Treatment of Oral Leukoplakia with CO2 and Diode Laser

INTRODUCTION

To analyze factors that may affect recurrence, development of new lesions, and malignant transformation in patients with oral leukoplakia (OL) following surgical treatment with lasers.

MATERIALS AND METHODS

A total of 40 patients were enrolled in this study, 17 females (mean age of 64.5 years; 33-88 years) and 23 males (mean age of 56.6 years; 28-84 years) with an overall mean age of 60.5 years. A total of 49 lesions were diagnosed and treated; 9 patients had more than one site affected. Mean time of follow-up was 22 months (6-71 months). Data were assessed by univariate Cox and multivariate Cox regression analyses.

RESULTS

Recurrence (OL at the same site of the initial lesion) was observed in 11 patients (27.5%) while 4 patients (10%) developed new lesions, and 2 patients (5%) experienced malignant transformation. Only two clinical factors were statistically associated with the outcome for the development of new lesions: patients ≥ 60 years and female gender (p < 0.1). Neither of the outcomes of recurrences and malignant transformations was significantly correlated with any of the risk factors analyzed.

CONCLUSION

Surgical laser is not a deterrent for the outcomes evaluated; additionally, the design of this study did not allow us to determine whether the laser treatment had provided a great benefit by significantly reducing the rate of malignant transformation among the patients.

CLINICAL SIGNIFICANCE

It is highly important to inform patients with OL that their condition can be treated, when possible, by surgical laser, and that this treatment may be helpful in bringing down the odds of malignant transformation of their lesions. In addition, the patients should also be brought to the attention of the necessity of a continued clinical monitoring regardless of the outcome following a surgical intervention.

Evaluation of Different Laser-Supported Surgical Protocols for the Treatment of Oral Leukoplakia: A Long-Term Follow-Up

PURPOSE

The aim of this study was to evaluate the long-term success rate of oral leukoplakia treatments by using different laser-supported surgical protocols.

PATIENTS AND METHODS

Overall, 2347 diagnosed homogeneous oral leukoplakias were treated with CO₂ laser and were included in this study. Different surgical protocols (P) were used: P1 (SV = superficial scanning) was a complete superficial vaporization of the leukoplakia by a scanning mode in two passages respecting an overlapping. Only the visible white area was treated in one surgical session independently of the lesion size. P2 (CR1x1) was a complete excision of the lesions until a tissular depth of 1 mm and 1 mm of surrounding healthy-like tissue were attained. The visible white area was treated in one surgical session independently of the lesion size. P3 (CR1x3) was a complete excision of the lesions until a minimum tissue depth of 1 mm and 3 mm of surrounding healthy-like tissue were obtained. The visible white area was treated in one surgical session independently of the lesion size. P4 (PR1x3) was similar to the third one, but for patient comfort, the large lesions of leukoplakias (lesion size higher than 20 mm), the complete surgical excision of the leukoplakia was performed in multiple sessions that were spaced by 1 month (partial surgical removal of 10 mm per session). All patients were recalled at 2 and 8 weeks after surgery, and then every 2 months during the first year, every 4 months during the second year, and once a year for the follow-up period of 6 years. A biopsy was done once a year during the follow-up period in the surgical site when needed. The control consisted of checking the nature and the aspect of the healed mucosa to exclude an eventual recurrence of leukoplakia.

RESULTS

The percentage of permanent success after 6 years of follow-up was 5.7%, 69.7%, 97.8%, and 71.9%, respectively, for the first surgical protocol (SV), the second (CR 1 × 1), the third (CR 1 × 3), and the fourth (PR 1 × 3). The appearance of malignant transformation after laser treatment (during the follow-up period of 6 years) was 20%, 1%, and 0.2%, respectively, for the groups treated by the following protocols: 1 (SV), 2 (CR 1 × 1), and 4 (PR 1 × 3). Only in the third group CR1x3, no dysplasia or malignant transformation was noted. On the contrary, the appearance of malignant transformation in failed treated cases was 21.21% for the protocol 1 (SV), 3% for the protocol 2 (CR 1 × 1), and 0.6% for the protocol 4 (PR 1 × 3).

CONCLUSIONS

The results of this long-term follow-up of treated patients with oral homogeneous leukoplakias pointed out that the surgical laser protocol respecting the complete excision of leukoplakias, in one session, by the removal of a minimum of 1 mm in lesion depth and 3 mm of surrounding healthy-like tissues (CR 1 × 3) offers significantly the highest success rate.

A Low-Level Carbon Dioxide Laser Promotes Fibroblast Proliferation and Migration through Activation of Akt, ERK, and JNK

BACKGROUND

Low-level laser therapy (LLLT) with various types of lasers promotes fibroblast proliferation and migration during the process of wound healing. Although LLLT with a carbon dioxide (CO2) laser was also reported to promote wound healing, the underlying mechanisms at the cellular level have not been previously described. Herein, we investigated the effect of LLLT with a CO2 laser on fibroblast proliferation and migration.

MATERIALS AND METHODS

Cultured human dermal fibroblasts were prepared. MTS and cell migration assays were performed with fibroblasts after LLLT with a CO2 laser at various doses (0.1, 0.5, 1.0, 2.0, or 5.0 J/cm2) to observe the effects of LLLT with a CO2 laser on the proliferation and migration of fibroblasts. The non-irradiated group served as the control. Moreover, western blot analysis was performed using fibroblasts after LLLT with a CO2 laser to analyze changes in the activities of Akt, extracellular signal-regulated kinase (ERK), and Jun N-terminal kinase (JNK), which are signaling molecules associated with cell proliferation and migration. Finally, the MTS assay, a cell migration assay, and western blot analysis were performed using fibroblasts treated with inhibitors of Akt, ERK, or JNK before LLLT with a CO2 laser.

RESULTS

In MTS and cell migration assays, fibroblast proliferation and migration were promoted after LLLT with a CO2 laser at 1.0 J/cm2. Western blot analysis revealed that Akt, ERK, and JNK activities were promoted in fibroblasts after LLLT with a CO2 laser at 1.0 J/cm2. Moreover, inhibition of Akt, ERK, or JNK significantly blocked fibroblast proliferation and migration.

CONCLUSIONS

These findings suggested that LLLT with a CO2 laser would accelerate wound healing by promoting the proliferation and migration of fibroblasts. Activation of Akt, ERK, and JNK was essential for CO2 laser-induced proliferation and migration of fibroblasts.

Investigation of the differentiation of ex vivo nerve and fat tissues using laser-induced breakdown spectroscopy (LIBS): Prospects for tissue-specific laser surgery

In the present study, the elemental compositions of fat and nerve tissue during their plasma mediated laser ablation are studied in the context of tissue differentiation for laser surgery applications by using Laser-Induced Breakdown Spectroscopy (LIBS). Tissue samples of porcine fat and nerve were prepared as ex vivo experimental objects. Plasma mediated laser ablation is performed using an Nd : YAG laser in open air and under normal stray light conditions. The performed measurements suggest that the two tissue types show a high similarity in terms of qualitative elemental composition while at the same time revealing a distinct difference in the concentration of the constituent elements. Different analysis approaches are evaluated and discussed to optimize the tissue-differentiation performance of the LIBS approach. Plasma mediated laser tissue ablation.

Oral leukoplakia treatment with the carbon dioxide laser: A systematic review of the literature

We conducted a systematic review of the literature to evaluate treatment of oral leukoplakia with the carbon dioxide (CO2) laser. A comprehensive search of studies published between 1981 and 2015 and listed in the PubMed (National Library of Medicine, NCBI) database yielded 378 articles which were screened in detail. Relevant studies were selected according to predetermined inclusion and exclusion criteria. A total of 33 articles met the final inclusion criteria and were analysed in detail in accordance with the PRISMA-P statement. These full-text papers were classified as synopses (n = 7), recurrence and malignant transformation studies (n = 17), comparative studies between CO2 laser and cold knife surgery (n = 3) and studies evaluating the efficacy of CO2, Nd:YAG and KTP lasers. According to the literature the CO2 laser is the workhorse of oral leukoplakia treatment due to its effectiveness and low associated morbidity. However, randomized clinical trials are needed to compare CO2 laser with other lasers. The results of our systematic review showed that there is no consensus regarding the factors involved in higher recurrence and malignization rates, so further studies are needed.

Oral precursor lesions and malignant transformation--who, where, what, and when?

Oral potentially malignant disorders (PMD) are recognisable mucosal conditions that have an unpredictable risk of transformation to squamous cell carcinoma (SCC), a lethal and deforming disease of rising incidence. Contemporary management is based on clinical recognition of suspicious lesions and incisional biopsy to enable histopathological assessment and grading of dysplasia, together with excision of high-risk lesions and long-term surveillance. However, it is impossible to predict clinical outcome or risk of malignant transformation. Our aim was to evaluate the relevance of previously identified oral precursor lesions for the development of SCC and staging of disease. We therefore retrospectively reviewed 1248 cases of SCC diagnosed in oral and maxillofacial surgery units at Newcastle upon Tyne and Sunderland hospitals between 1996 and 2009. Of them, 58 identifiable precursor lesions became malignant but only 25 had been dysplastic on initial biopsy; 19 of 33 non-dysplastic lesions exhibited lichenoid inflammation only. SCC arose most often on the ventrolateral tongue and floor of the mouth, with a mean transformation time of 29.2 months. Transformation time was significantly shorter in men (p=0.018) and those over 70 years of age (p=0.010). Patients who consumed more than 21 units of alcohol/week and those who had had interventional laser surgery to treat precursor lesions, had higher-staged tumours (p=0.048). Although retrospective, this study shows that the results of incisional biopsy and grading of dysplasia have limited use as predictive tools, and supports the view that cancer may arise in the absence of recognisable epithelial dysplasia. Our findings confirm the importance of clinical vigilance and active surveillance in the management of all patients with clinically suspicious oral lesions, irrespective of the histological findings.

To treat...or not to treat? Clinicians' views on the management of oral potentially malignant disorders

Oral potentially malignant disorders (PMD) are recognisable mucosal conditions that have a variable and unpredictable risk of transformation to invasive squamous cell carcinoma (SCC). Modern management relies initially on clinical recognition of suspicious lesions and histopathological assessment and grading after incisional biopsy. However, it then varies from wide excision to observation and review, and depends not only on the severity of dysplasia but also on the clinician's preference as there is no high-level evidence to support best practice. We invited clinicians from oral and maxillofacial surgery, oral medicine, ear, nose, and throat (ENT), and plastic surgery, to complete an online questionnaire on current practice, which included 3 fictitious cases, to ascertain their views on the management of PMD and to find out whether they would be interested in becoming involved in a proposed future randomised controlled trial (RCT). Of the 251 who replied, 178 (71%) were oral and maxillofacial surgeons, and 99 (39%) expressed an interest in participating in a future RCT. Most respondents (n=164 or 99%) would always treat severely dysplastic lesions by excision or laser ablation, whereas only 8% (n=13) would always excise mild dysplasia. The greatest equipoise among those interested in taking part in a RCT was found in the case of moderate dysplasia for which 27% (n=27) favoured observation compared with surgical excision or laser ablation. This study shows that there is support for a multicentre, prospective RCT that compares observation with resection and laser ablation in patients with moderate dysplasia.

Managing oral potentially malignant disorders:A question of risk

The concept of an oral disease process that presents as a ‘potentially malignant state’ that is neither entirely benign nor frankly malignant is a difficult concept both for clinicians and their affected patients. While it is recognised that a range of oral mucosal conditions, now collectively termed ‘potentially malignant disorders’, harbour an increased risk of squamous carcinoma, we remain frustratingly unable in contemporary clinical practice to predict individual lesion behaviour, quantify the risk of malignant transformation or objectively plan interventions.

Clinical predictors of oral leukoplakia recurrence following CO₂ laser vaporization

OBJECTIVE

The objective of this study was to determine whether risk of early leukoplakia recurrence (within 3 months) following carbon dioxide (CO2) laser removal varies by clinical characteristics including lesion size, site and accessibility of margins.

MATERIALS AND METHODS

A retrospective cohort study included patients with oral leukoplakia who had their first CO2 laser surgery for removal of oral leukoplakia between 2005 and 2010 at the UCSF oral medicine clinic. Twenty-six patients with 32 separate lesions met the eligibility criteria after a clinic database search was followed by review of clinical notes and biopsy reports from existing patient charts. Data analysis included computation of summary statistics, and logistic regression analyses to evaluate recurrence of leukoplakia by clinical characteristics of the lesions.

RESULTS

Patient data and the characteristics of lesions were evaluated as possible predictors of early recurrence following laser removal; these included age, sex, duration, size, appearance and histopathology of the lesion. The only one that reached statistical significance was poor accessibility of the margins of the lesion (vs. good accessibility, OR = 24.57 (95% CI: 1.59-16.68), p = 0.016); the probability for trend for good, questionable, and poor accessibility was 0.0028. This finding remained significant after controlling for age, sex, duration and size of lesion. Four out of five lesions with poor accessibility showed recurrence at 3 months. Of these, three involved the gingiva and one the lateral tongue.

CONCLUSIONS

This study has identified poor accessibility of the lesion margins as a predictor for early recurrence of leukoplakia following laser removal. Other variables evaluated did not reach statistical significance, possibly due to lack of power.

Estimation of oral leukoplakia treatment records in the research of the Department of Maxillofacial and Oral Surgery, Medical University of Gdansk

Introduction

Oral leukoplakia (OL) is the most common potentially malignant lesion of the oral cavity.

Aim

The purpose of the study was clinical and epidemiological analysis of patients with OL diagnosed and treated in the Department of Maxillofacial and Oral Surgery, Medical University of Gdansk, comparison of effectiveness of treatment methods, defining whether van der Waal level of OL influences treatment effectiveness, correlation between localization of OL and treatment effectiveness, and defining the optimal OL therapeutic method.

Material and methods

Among 55 911 patients diagnosed and treated in the Department in the years 1999–2009, 204 people with OL were selected (104 women, 100 men, average age: 58.1 years). Treatment and observation period of 6 months was completed by 178 (87.25%) patients. Seventy-four patients were treated with cream containing 0.05% tretinoin. Sixty-three patients underwent cryosurgery, and 41 surgery. Control visits were made in week 2, 4, 6 and 8 and 6 months after completed treatment.

Results

Three hundred and twenty lesions of OL were diagnosed. According to van der Waal classification, the largest group of patients was classified into stage I and II. The percentage of totally cured patients was 90.07%. There were no statistic differences in effectiveness between surgical and cryosurgical treatment.

Conclusions

Evaluation of OL treatment methods depends on localization of the lesions and its stage of progression. The effectiveness of treatment with locally applied tretinoin is smaller in comparison to surgery and cryosurgery. It allows to reduce the number and size of OL lesions, what makes it possible to reduce the number of ablative procedures.

The treatment of oral leukoplakia with the CO2 laser: A retrospective study of 65 patients

The use of CO2 laser has become a routine procedure for the treatment of oral leukoplakia. In this retrospective study, we evaluated 65 patients with oral leukoplakia treated with CO2 laser vaporization. The main location was the tongue (n = 21/65, 32.3%). The initial biopsy showed mild/moderate dysplasia in almost half the patients (n = 29, 44.6%) and hyperplasia without dysplasia in around a third of the patients (n = 21, 32.3%). The recurrence and malignant transformation rates were 33.8% (n = 22) and 15.4% (n = 10), respectively. The follow-up mean (standard deviation) was 15.0 (10.6) months. The procedure-related complications rate was 7.7% (n = 5). The Kaplan-Meier curves for time to recurrence showed differences only for gingiva lesions compared to tongue lesions (log rank, p = 0.032). Malignant leukoplakia transformation is independent of treatment, although it seems advisable to treat leukoplakia with or without dysplasia.

The role of interventional surgery in oral potentially malignant disorders

Oral potentially malignant disorders are mucosal diseases with a significantly increased risk of squamous carcinoma development – a lethal and deforming disease with rising incidence, especially in young people. Despite the ability to recognise pre-cancer disorders in patients, clinicians remain unable to predict individual mucosal lesion behaviour or quantify the risk of malignant transformation. No clear management guidelines exist and the available scientific literature is unable to answer the fundamental question: does early diagnosis and interventional management treat pre-cancer effectively and prevent malignant transformation?

Management for premalignant lesions of the oral cavity

Premalignant lesions of the oral cavity present as visibly abnormal areas of mucosa and may be a source of significant anxiety for the patient and the clinician. Suspicious lesions should be biopsied to evaluate for dysplasia. The risk of malignant transformation may relate to patient characteristics, environmental risk factors and genetic alterations. Management of such lesions hinges on risk modification, surveillance, symptom management and directed biopsies. Excision or ablation of dysplastic lesions is indicated. We review the current evidence relating to management of premalignant lesions of the oral mucosa and make recommendations for practice patterns.

Labial frenectomy with Nd:YAG laser and conventional surgery: a comparative study

Labial frenulums are sagittal fibrous folds of oral mucosa with a periosteal insertion that extend from the lips to the alveolar or gingival mucosa. Occasionally, they assume inadequate size or location and may lead to functional and esthetic limitations. The aim of the present study was to compare pre-, trans-, and postsurgical clinical parameters of labial frenectomies performed with conventional surgery and neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. Forty individuals were assessed as a convenience sample and were divided into two groups according to the treatment: group 1 (G1), conventional surgery (n = 22), and G2, Nd:YAG laser surgery (n = 18). Clinical parameters such as frenulum insertion, location, bleeding, surgical time, suturing, preoperative fear, and postoperative discomfort/functional limitations were evaluated. All surgeries were performed by the same operator, and the level of fear, pain, and discomfort related to oral functions were assessed with a visual numeric scale. Most of the frenulums (90%) were classified as papillary or transpapillary insertion. Preoperative fear was similar between groups (p = 0.593). All G2 patients did not require suture (p < 0.001), did not bleed during the procedure (p < 0.001), and had surgical time diminished (p < 0.001). No significant statistical difference regarding pain or oral function could be observed. Three individuals (7.5%) experienced postsurgical complications. Nd:YAG laser frenectomies reduces transoperative bleeding, avoiding the need of suturing, and promotes a significant reduction of surgical time in comparison with conventional surgery. Therefore, further studies are necessary to provide a complete understanding and standardization of the technique as well as the expected clinical results.

Clinical outcome following oral potentially malignant disorder treatment: a 100 patient cohort study

Oral potentially malignant disorders (PMDs) are at risk of transforming to invasive squamous cell carcinoma (SCC), but controversy exists over their management and the precise role of interventional treatment. In this study, a cohort of 100 patients presenting with new, single oral dysplastic PMD lesions were followed for up to 10 years following laser excision. PMDs presented primarily as homogeneous leukoplakias on floor of mouth and ventrolateral tongue sites and showed mainly high-grade dysplasia following analysis of excision specimens. Sixty-two patients were disease-free at the time of the most recent followup, whilst 17 experienced same site PMD recurrence, 14 developed further PMDs at new sites, 5 underwent same site malignant transformation, and 2 developed SCC at new oral sites. Whilst laser excision is an effective therapeutic tool in PMD management, prolonged patient followup and active mucosal surveillance together with clear definitions of clinical outcomes are all essential prerequisites for successful interventional management. Multicentre, prospective, and randomised trials of PMD treatment intervention are urgently required to determine optimal management strategies.

Comparison of pain and swelling after removal of oral leukoplakia with CO₂ laser and cold knife: a randomized clinical trial

Objective: The aim of this study was to compare conventional surgery with carbon dioxide (CO2) laser in patients with oral leukoplakia, and to evaluate the postoperative pain and swelling. Study design: A total of 48 patients (27 males and 21 females) with a mean age of 53.7 ± 11.7 years and diagnosed with oral leukoplakia were randomly assigned to receive treatment either with conventional surgery using a cold knife or with a CO2 laser technique. A visual analog scale (VAS) was used to score pain and swelling at different postoperative time points. Results: Pain and swelling reported by the patients was greater with the conventional cold knife than with the CO2 laser, statistically significant differences for pain and swelling were observed between the two techniques during the first three days after surgery. Followed by a gradual decrease over one week. In neither group was granuloma formation observed, and none of the patients showed malignant transformation during the period of follow-up. Conclusions: The CO2 laser causes only minimal pain and swelling, thus suggesting that it may be an alternative method to conventional surgery in treating patients with oral leukoplakia.

Key words:Oral leukoplakia, treatment, laser surgery, cold knife, pain, swelling.