Delays in oral cavity cancer

The association between referral by specialists in oral diagnosis on survival rates of patients with oral cancer: A retrospective cohort study

BACKGROUND

To assess the influence of diagnosis and referral provided by specialists in oral diagnosis on disease-free survival and overall survival of patients with oral cancer.

METHODS

A cohort of 282 patients with oral cancer treated at a regional cancer hospital from 1998 to 2016 was analyzed retrospectively. The referral register of the patients was analyzed and assigned to two groups: (1) those referred by oral diagnosis specialists (n = 129), or (2) those referred by nonspecialized professionals (n = 153). The cancer treatment evolution was assessed from the patients' records, and the outcome was registered concerning cancer recurrence and death. Sociodemographic and clinicopathological variables were explored as predictors of disease-free survival and overall survival.

RESULTS

Group 1 exhibited lower T stages and a reduced incidence of regional and distant metastases. Surgery was performed in 75.2% of cases in Group 1, while in Group 2, the rate was 60.8%. Advanced T stages and regional metastases reduced the feasibility of surgery. Higher TNM stages and tumor recurrence were associated with decreased disease-free survival, while surgical intervention was a protective factor. Higher TNM stage had a negative impact on the overall survival.

CONCLUSION

Specialized oral diagnosis did not directly impact disease-free survival and overall survival and did not influence the indication of surgery in oral cancer; however, it was associated with the diagnosis of early tumors and better prognosis.

An Acid-Responsive Iron-Based Nanocomposite for OSCC Treatment

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, characterized by invasiveness, local lymph node metastasis, and poor prognosis. Traditional treatment and medications have limitations, making the specific inhibition of OSCC growth, invasion, and metastasis a challenge. The tumor microenvironment exhibits mildly acidity and high concentrations of H2O2, and its exploitation for cancer treatment has been widely researched across various cancers, but research in the oral cancer field is relatively limited. In this study, by loading ultra-small Prussian blue nanoparticles (USPBNPs) into mesoporous calcium-silicate nanoparticles (MCSNs), we developed an acid-responsive iron-based nanocomposite, USPBNPs@MCSNs (UPM), for the OSCC treatment. UPM demonstrated excellent dual enzyme activities, generating toxic ·OH in a mildly acidic environment, effectively killing OSCC cells and producing O2 in a neutral environment to alleviate tissue hypoxia. The results showed that UPM could effectively inhibit the proliferation, migration, and invasion of OSCC cells, as well as the growth of mice solid tumors, without obvious systemic toxicity. The mechanisms may involve UPM inducing ferroptosis of OSCC cells by downregulating the xCT/GPX4/glutathione (GSH) axis, characterized by intracellular iron accumulation, reactive oxygen species accumulation, GSH depletion, lipid peroxidation, and abnormal changes in mitochondrial morphology. Therefore, this study provides empirical support for ferroptosis as an emerging therapeutic target for OSCC and offers a valuable insight for future OSCC treatment.

Primary Management of Operable Locally Advanced Oral Cavity Squamous Cell Carcinoma: Current Concepts and Strategies

INTRODUCTION

Locally advanced oral cavity carcinoma (LAOCSCC) is primarily treated with surgery followed by radiotherapy with or without chemotherapy.

METHODS

A review of literature using PubMED was performed for studies reporting the management of LAOCSCC. Based on the reviewed literature and opinions of experts in the field, recommendations were made.

RESULTS

Studies have shown that outcomes following resection of T4a and infranotch (inferior to mandibular notch) T4b are comparable. We discuss the concept of compartmental resection of LAOCSCC and issues concerning the management of the neck. Further, patients who refuse or are unable to undergo surgery can be treated with chemoradiotherapy with uncertain outcomes. The role of neoadjuvant chemotherapy has shown promise for organ (mandibular) preservation in a select subset of patients.

CONCLUSION

The management strategy for LAOCSCC should be determined in a multidisciplinary setting with emphasis on tumor control, functional preservation, and quality of life of the patient.

The effect of the COVID-19 pandemic on the diagnosis and progression of oral cancer

The COVID-19 pandemic placed a significant burden on healthcare resources, limiting care to emergent and essential services only. The objective of this study was to describe the effect of the COVID-19 pandemic on the diagnosis and progression of oral cancer lesions in Montreal, Canada. A retrospective analysis of health records was performed. Patients presenting for a new oncology consultation for an oral lesion suspicious for cancer between March 2018 and March 2022, within the Department of Oral and Maxillofacial Surgery of the McGill University Health Center, were included. Data was collected on sociodemographic characteristics, oral cancer risk behaviors of study participants, oral cancer delays, tumor characteristics, and clinical management. A total of 190 patients were included, 91 patients from the pre-pandemic period and 99 from the pandemic period. The demographic characteristics of the patients in the two periods were comparable. There was no significant difference in the patient, professional, or treatment delay between the two periods. There was a non-significant increase in pathologic tumor size during the pandemic, but the pathologic staging and postoperative outcomes were comparable to those of the pre-pandemic cohort. The results indicate that emergent care pathways for oral cancer treatment were efficiently maintained despite the pandemic shutdown of services.

General dentists' knowledge, perceptions, and practices regarding oral potentially malignant disorders and oral cancer in Indonesia

INTRODUCTION

The most effective means for reducing oral cancer (OC) mortality is by preventing late-stage disease. Early diagnosis can be improved by increasing awareness among healthcare providers, specifically general dental practitioners (GDP). Therefore, our study aimed to assess GDPs' knowledge of OC risk factors and perceived competence in performing conventional oral examination (COE) in routine dental practice.

MATERIAL AND METHODS

This was a cross-sectional study conducted in five provinces of Indonesia, namely: Aceh, Banda Aceh (BA); Bandung, West Java (WJ); special district Jakarta (JKT), JKT; Pontianak, West Kalimantan (WK); and Sorong, West Papua (WP). The local Dental Association or Faculty of Dentistry invited the GDPs to attend an education program and complete the survey.

RESULTS

One hundred seventy-seven GDPs completed the survey (WJ, n = 63; BA, n = 44, JKT, n = 27; WP, n = 23; and WP, n = 20). A large proportion (164 out of 177, 92.66%) of GDPs felt they had received insufficient training to equip them to diagnose OC and as many as 22.6% (n = 40) did not refer to specialists when they found suspicious mucosal lesions. Notwithstanding the significant regional variations, the majority of Indonesian GDPs self-reported inadequate knowledge and awareness of OC and scarce confidence in performing COE.

CONCLUSION

GDP knowledge of OC risk factors and COE is key to improving early diagnosis of OC at a community level. Therefore, it is suggested that the lack of knowledge and confidence of GDPs reported here should be addressed through the national dental curriculum in Indonesia.

Knowledge, attitude, and practice in oral cancer: A national survey on 150 dental hygienists

OBJECTIVE

The aim of this study is to explore knowledge, practice, and attitude on oral cancer (OC) among a cohort of Italian dental hygienists, in consideration of their role in the field of early diagnosis.

MATERIALS AND METHODS

A cross-sectional study of 150 Italian dental hygienists was performed to assess the participant's knowledge, practice, and attitude on OC. Data were collected using a structured self-administered questionnaire (through Google Forms). The questionnaire included four sections: sociodemographic information, disease knowledge, answers related to attitudes toward OC, and a questionnaire assessing the practice of dental hygienists on oral screening.

RESULTS

Responses were received from 137 participants (83 women and 54 men). Overall, there is a good knowledge of the real risk factors among the participants (98.5%, 98.5%, and 94.2% regard smoking, alcohol, and HPV, respectively). The analysis related to the knowledge of non-risk factors, oral potentially malignant disorders, and clinical features of OC showed more heterogeneous results. Only 60% considered university education to be adequate. The totality of dental hygienists considered continuing education necessary, but despite this, only half took updating courses. Finally, 90% performed intraoral screening visits, and 95% and 69% investigated smoking and alcohol consumption, respectively.

CONCLUSIONS

Our data showed the need to implement OC training courses by re-evaluating pre- and post-graduate training programs.

Delay in health-seeking behaviour and associated factors among adult patients with cancer in Ethiopia: a multicentre cross-sectional study

OBJECTIVES

Delays in obtaining proper cancer treatment can lead to advanced stages at diagnosis. Despite the problems, there is not enough evidence regarding delay in presentation. This study aims to assess delay in health-seeking behaviour and associated factors among adult patients with cancer in Ethiopia.

DESIGN

Multicentre cross-sectional study design.

SETTING

Data were collected from selected oncology centres in Ethiopia.

PARTICIPANTS

A multistage sampling technique was used to select 635 study participants from May 9 to June 9 2022.

OUTCOME MEASURES

Patients who have a duration of ≥3 months from symptom recognition to the first healthcare visit were considered as delay in health-seeking behaviour. Data were entered using Epi data and exported to SPSS for further analysis. Before analysis, model fitness was carried out using Hosmer and Lemeshow test. Variables with a p value<0.25 in the bivariable analysis were included in multivariable logistic regression. In multivariable logistic regression, a p value<0.05 significant level was considered as the factor for delay in health-seeking behaviour.

RESULTS

In this study, a total of 628 adult patients with cancer participated. A total of 72.6% of patients had a delay in health-seeking behaviour. Variables such as being female (AOR=2.81; 95% CI=1.29 to 6.14), rural residence (AOR=2.82; 95% CI=1.43 to 5.58), low social support (AOR=4.16; 95% CI=2.04 to 8.49), not having comorbidity (AOR=4.44; 95% CI=2.28 to 8.66), stage III cancer (AOR=3.73; 95% CI=1.37 to 9.98), stage IV cancer (AOR=3.07; 95% CI=1.28 to 6.41), additional symptoms (AOR=3.03; 95% CI=1.55 to 5.94), never heard about cancers (AOR=4.09; 95% CI=2.06 to 8.11) and never heard about cancer screening (AOR=2.16; 95% CI=1.06 to 4.40) were identified as factors for delay in health-seeking behaviour.

CONCLUSION

This study showed that relatively higher magnitude in which approximately three-fourth of adult patients with cancer were delayed in seeking medical attention. As a result, more effort must be made to tackle delay in health-seeking behaviour and associated factors.

The duration of intervals on the oral cancer care pathway and implications for survival: a systematic review and meta-analysis

Introduction

Previous studies measuring intervals on the oral cancer care pathway have been heterogenous, showing mixed results with regard to patient outcomes. The aims of this research were (1) to calculate pooled meta-analytic estimates for the duration of the patient, diagnostic and treatment intervals in oral cancer, considering the income level of the country, and (2) to review the evidence on the relationship of these three intervals with tumor stage at diagnosis and survival.

Materials and methods

We conducted a systematic review with meta-analysis following PRISMA 2020 guidelines (pre-registered protocol CRD42020200752). Following the Aarhus statement, studies were eligible if they reported data on the length of the patient (first symptom to first presentation to a healthcare professional), diagnostic (first presentation to diagnosis), or treatment (diagnosis to start of treatment) intervals in adult patients diagnosed with primary oral cancer. The risk of bias was assessed with the Aarhus checklist.

Results

Twenty-eight studies reporting on 30,845 patients met the inclusion criteria. The pooled median duration of the patient interval was 47 days (95% CI = 31-73), k = 18, of the diagnosis interval 35 days (95% CI = 21-38), k = 11, and of the treatment interval 30 days (95% CI = 23-53), k = 19. In lower-income countries, the patient and treatment intervals were significantly longer, and longer patient intervals were related to later stage at diagnosis. In studies with a lower risk of bias from high-income countries, longer treatment intervals were associated with lower survival rates.

Conclusion

Interval duration on the oral cancer care pathway is influenced by the socio-economic context and may have implications for patient outcomes.

Oral and oropharyngeal cancer: time from first symptoms to treatment initiation and associated factors

The aim of this study was to evaluate the time elapsed from first symptoms to the treatment of oral and oropharyngeal cancer (OOC) and to identify variables associated with treatment delay. This is an observational study with retrospective and prospective data collection. Patients with a diagnosis of OOC seen at the Head and Neck Surgery outpatient clinic of a Brazilian public hospital were included and followed up to treatment initiation. Participants answered a questionnaire for the collection of socioeconomic, demographic, cultural, and clinical information, as well as information about the time elapsed from first symptoms to the first appointment with a head and neck surgeon. Time to treatment was classified into four intervals: 1- first symptoms to first medical appointment; 2- first medical appointment to specialized medical care; 3- specialized medical care to preparation for treatment; and 4- preparation for treatment to treatment initiation. Bivariate statistics were computed. Out of 100 participants, nine died before treatment. Mean time to treatment was 217 days. Highest mean time was observed for interval 2 (94 days), followed by interval 1 (63 days), interval 4 (39 days), and interval 3 (21 days). At interval 1, a longer time was associated with severe alcohol consumption, severe smoking, and family history of cancer. At interval 2, the delay was associated with appointment with a general practitioner, clinical diagnosis of disease other than cancer, and antibiotic prescription. At interval 4, delay in treatment was associated with surgical treatment. Patients with OOC experience delays from symptom onset to treatment initiation. The longest interval was associated with professional delay, followed by patient delay in help-seeking.

Diagnostic delay of oral squamous cell carcinoma and the fear of diagnosis: A scoping review

The mortality rate of patients affected with oral squamous cell carcinoma (OSCC) has been stable in recent decades due to several factors, especially diagnostic delay, which is often associated with a late stage diagnosis and poor prognosis. The aims of this paper were to: analyze diagnostic delay in OSCC and to discuss the various psychological factors of patients with OSCC, with particular attention to the patient's fear of receiving news regarding their health; and the professional dynamics related to the decision-making processes in cases of suspected OSCC. A preliminary review of literature focusing on OSCC diagnostic delay was performed. Seven articles were included with the diagnostic delay ranging from 45  days to approximately 6  months. Patients' fears and, to a lesser degree, the concerns of dentists, were found to be still poorly investigated. On the basis of the authors' professional experience, the development of oral lesions of unknown origin may generate different behaviors in the decision-making processes by patients and clinicians, and fear may play a key role in the distinct steps of this process. It is crucial to increase awareness and inform patients about the onset of OSCC, and contemporaneously encourage experimental studies on patients' fear and professional behaviors with respect to communication regarding OSCC.

Nanophotosensitizers Composed of Phenyl Boronic Acid Pinacol Ester-Conjugated Chitosan Oligosaccharide via Thioketal Linker for Reactive Oxygen Species-Sensitive Delivery of Chlorin e6 against Oral Cancer Cells

Chlorin E6 (Ce6)-incorporated nanophotosensitizers were fabricated for application in photodynamic therapy (PDT) of oral cancer cells. For this purpose, chitosan oligosaccharide (COS) was conjugated with hydrophobic and reactive oxygen species (ROS)-sensitive moieties, such as phenyl boronic acid pinacol ester (PBAP) via a thioketal linker (COSthPBAP). ThdCOOH was conjugated with PBAP to produce ThdCOOH-PBAP conjugates and then attached to amine groups of COS to produce a COSthPBAP copolymer. Ce6-incorporated nanophotosensitizers using the COSthPBAP copolymer were fabricated through the nanoprecipitation and dialysis methods. The Ce6-incorporated COSthPBAP nanophotosensitizers had a small diameter of less than 200 nm with a mono-modal distribution pattern. However, it became a multimodal and/or irregular distribution pattern when H₂O₂ was added. In a morphological observation using TEM, the nanophotosensitizers were disintegrated by the addition of H₂O₂, indicating that the COSthPBAP nanophotosensitizers had ROS sensitivity. In addition, the Ce6 release rate from the COSthPBAP nanophotosensitizers accelerated in the presence of H₂O₂. The SO generation was also higher in the nanophotosensitizers than in the free Ce6. Furthermore, the COSthPBAP nanophotosensitizers showed a higher intracellular Ce6 uptake ratio and ROS generation in all types of oral cancer cells. They efficiently inhibited the viability of oral cancer cells under light irradiation, but they did not significantly affect the viability of either normal cells or cancer cells in the absence of light irradiation. The COSthPBAP nanophotosensitizers showed a tumor-specific delivery capacity and fluorescence imaging of KB tumors in an in vivo animal tumor imaging study. We suggest that COSthPBAP nanophotosensitizers are promising candidates for the imaging and treatment of oral cancers.

Improving the Diagnostic Performance by Adding Methylation Marker to Conventional Visual Examination in Identifying Oral Cancer

Background: Visual oral examination (VOE) is a conventional oral cancer screening method. This study aimed to evaluate the value of methylation marker to assist VOE in identifying oral epithelial dysplasia and oral squamous cell carcinoma (OED/OSCC) from non-cancerous lesions in a real-world situation. Methods: 201 patients with high-risk personal habits who self-perceived oral anomaly were VOE examined, ZNF582 methylation (ZNF582^m) tested, and histologically diagnosed. Results: Among them, 132 patients (65.7%) were histologically diagnosed OED/OSCC. Using VOE, 56.1% OED/OSCC patients had possible oral cancer, whereas 37.7% non-OED/OSCC patients had leukoplakia. ZNF582^m-positive was detected in 90.2% OED/OSCC patients and 44.9% non-OED/OSCC patients. Various logistic regression models were postulated to evaluate the diagnostic performance of conventional VOE and new strategies using ZNF582^m. ROC analysis and its corresponding C-index demonstrated that either triage or co-testing models of VOE and ZNF582^m could improve diagnostic performance and discriminative abilities compared with the VOE only approach. Conclusions: In conclusion, methylation marker test shows equivalent performance to an experienced judgment by oral maxillofacial surgeons and plays a significantly supplementary role in increasing the efficacy in identifying oral malignant lesions. ZNF582^m may be an especially important tool for family physicians or general dentists to properly diagnose suspicious oral lesions.

Clinical Outcomes and Cost Analysis of Fibula Free Flaps: A Retrospective Comparison of CAD/CAM versus Conventional Technique

(1) Background: A decrease in operative time can not only improve patient outcomes through a reduction in the risk of developing complications but can also result in cost savings. The aim of this study is to determine whether there an intraoperative time gain can be achieved by using the preoperative virtual planning of mandibular reconstruction using a free fibula flap compared with freehand plate bending and osteotomies. (2) Methods: A retrospective comparative study was carried out in the Oral and Maxillofacial Department of La Paz University Hospital, Madrid, Spain. The study compared 18 patients in the CAD/CAM group with 19 patients in the conventional freehand group. A comparison was made between the total surgical time, the comorbidities, and the hospital stay. The resource consumption was estimated using a cost analysis. (3) Results: Although CAD/CAM was a statistically more expensive procedure in the perioperative phase, no significant differences were observed in total health care costs between the two groups. There was a non-significant trend towards an increase in complications with conventional reconstruction plates compared to patient-specific plates (PSI). (4) Conclusions: CAD/CAM technology and a 3D printed cutting guide offer a significantly shorter surgical time, which is associated with a reduction in hospital days, PACU days, and complications. The cost of CAD/CAM technology is comparable to that of the conventional freehand technique.

Gold nanomaterials for oral cancer diagnosis and therapy: Advances, challenges, and prospects

Early diagnosis and treatment of oral cancer are vital for patient survival. Since the oral cavity accommodates the second largest and most diverse microbiome community after the gut, the diagnostic and therapeutic approaches with low invasiveness and minimal damage to surrounding tissues are keys to preventing clinical intervention-related infections. Gold nanoparticles (AuNPs) are widely used in the research of cancer diagnosis and therapy due to their excellent properties such as surface-enhanced Raman spectroscopy, surface plasma resonance, controlled synthesis, the plasticity of surface morphology, biological safety, and stability. AuNPs had been used in oral cancer detection reagents, tumor-targeted therapy, photothermal therapy, photodynamic therapy, and other combination therapies for oral cancer. AuNPs-based noninvasive diagnosis and precise treatments further reduce the clinical intervention-related infections. This review is focused on the recent advances in research and application of AuNPs for early screening, diagnostic typing, drug delivery, photothermal therapy, radiotherapy sensitivity treatment, and combination therapy of oral cancer. Distinctive reports from the literature are summarized to highlight the latest advances in the development and application of AuNPs in oral cancer diagnosis and therapy. Finally, this review points out the challenges and prospects of possible applications of AuNPs in oral cancer diagnosis and therapy.

Factors Associated With a Prolonged Diagnosis-to-Treatment Interval in Laryngeal Squamous Cell Carcinoma

OBJECTIVE

Evaluate factors associated with treatment delays and their effect on survival in laryngeal squamous cell carcinoma.

STUDY DESIGN

Retrospective cohort study.

SETTING

National Cancer Database.

METHODS

Patients receiving primary radiation or surgery for laryngeal squamous cell carcinoma were included from 2004 to 2017. The primary outcomes were the diagnosis-to-treatment interval (DTI) and 5-year survival. Variables of prolonged DTI (>30 days) were assessed via logistic regression models. Survival was then assessed through Cox proportional hazards models. Candidate variables for both outcomes included age, sex, race, ethnicity, distance to treatment facility, insurance coverage, treatment facility type, TNM T stage, nodal status, and DTI (in models estimating survival).

RESULTS

An overall 136,203 patients with laryngeal cancer were identified, from which 51,747 remained after exclusions were applied: 18,499 received primary surgery and 33,248 received primary radiation. Being a member of a racial or ethnic minority, advanced age, female sex, ≥30 miles from treatment facility, lack of insurance, treatment at an academic cancer center, and primary radiation were associated with a prolonged DTI. However, in spite of a faster DTI, treatment at a community cancer center was independently associated with higher mortality (hazard ratio, 1.2; P < .0001).

CONCLUSIONS

Despite being associated with prolonged DTI, receiving treatment at a high-volume academic facility was associated with significantly improved survival. Our results indicate that improved referral pathways or outreach may help improve survival in laryngeal cancer, especially in high-risk populations.

Reexamination of delays in diagnosis of oral cancer following an intervention program in Cordoba, Argentina

OBJECTIVE

We compare the results of delay in oral cancer diagnosis before and after a campaign directed toward dentists and raising awareness of the population to achieve early diagnosis of oral cancer in Córdoba, Argentina. The campaign included training dentists in diagnostic skills and a public awareness program through media and networks.

STUDY DESIGN

Clinical records (period 1: before intervention program, n = 70; period 2: after intervention program, n = 60) of patients presenting with oral squamous cell carcinoma treated in 2 referral centers were analyzed. Records included first symptoms, first consultation with a health professional, and the time when treatment was formulated.

RESULTS

Oral cancer diagnosis at early stages increased from 27% (period 1) to 40% (period 2). Biopsy at first consultation was indicated in 6% of patients in period 1 and in 23.3% in period 2 (odds ratio = 4.68; 95% confidence interval, 1.87-11.73; P < .05). Professional delay at early stage decreased from 72% in period 1 to 36.8% in period 2. During period 1, for initial stage cancer, the average patient and professional delays were 2.7 and 2.9 months, respectively (P = .06); in period 2, patient delay was 2.67 months and professional delay was 1.34 months (P = .005).

CONCLUSION

The intervention program helped to improve early-stage diagnosis from 27% to 40% by reducing professional delays.

Butyrate promotes oral squamous cell carcinoma cells migration, invasion and epithelial-mesenchymal transition

BACKGROUND

Oral squamous cell carcinoma (OSCC), the most common type of primary malignant tumor in the oral cavity, is a lethal disease with high recurrence and mortality rates. Butyrate, a metabolite produced by periodontal pathogens, has been linked to oral diseases. The purpose of this study was to evaluate the effect of sodium butyrate (NaB) on the proliferation, migration, and invasion of OSCC cells in vitro and to explore the potential mechanism.

METHODS

Two OSCC cell lines (HSC-4 and SCC-9) were treated with NaB at different concentrations. The cell proliferation was assayed by CCK-8, ethylene deoxyuridine (EdU), and flow cytometry. Wound healing and transwell assay were performed to detect cell migration and invasion. Changes in epithelial-mesenchymal transition (EMT) markers, including E-cadherin, Vimentin, and SNAI1, were evaluated by quantitative real-time PCR (qRT-PCR), western blot, and immunofluorescent staining. The expression levels of matrix metalloproteinases (MMPs) were analyzed by qRT-PCR and gelatin zymography.

RESULTS

Our results showed that NaB inhibited the proliferation of OSCC cells and induced cell cycle arrest at G1 phase, but NaB significantly enhanced cell migration and invasion compared with the control group. Further mechanistic investigation demonstrated that NaB induced EMT by increasing the expression of Vimentin and SNAI1, decreasing the expression of membrane-bound E-cadherin, and correspondingly promoting E-cadherin translocation from the membrane to the cytoplasm. In addition, the overexpression of MMP1/2/9/13 was closely related to NaB treatment.

CONCLUSIONS

Our study conclude that butyrate may promote the migration and invasion of OSCC cells by inducing EMT. These findings indicate that butyrate may contribute to OSCC metastasis.

Circulating Natural Autoantibodies to HER2-Derived Peptides Performed Antitumor Effects on Oral Squamous Cell Carcinoma

Natural autoantibodies play a crucial role in destruction of malignant tumors due to immune surveillance function. Epidermal growth factor receptor 2 (HER2) has been found to be highly expressed in a variety of epithelial tumors including oral squamous cell carcinoma (OSCC). The present study was thus undertaken to investigate the effect of anti-HER2 natural autoantibodies on OSCC. Compared with cancer-adjacent tissues, cancer tissues from OSCC patients exhibited higher HER2 expression especially in those with middle & advanced stage OSCC. Plasma anti-HER2 IgG levels examined with an enzyme-linked immunosorbent assay (ELISA) developed in-house showed differences between control subjects, individuals with oral benign tumor and patients with OSCC. In addition, anti-HER2 IgG-abundant plasma was screened from healthy donors to treat OSCC cells and to prepare for anti-HER2 intravenous immunoglobulin (IVIg). Both anti-HER2 IgG-abundant plasma and anti-HER2 IVIg could significantly inhibit proliferation and invasion of OSCC cells by inducing the apoptosis, and also regulate apoptosis-associated factors and epithelial-mesenchymal transition (EMT), respectively. Besides, the complement-dependent cytotoxicity (CDC) pathway was likely to contribute to the anti-HER2 IgG mediated inhibition of OSCC cells. After the HER2 gene was knocked down with HER2-specific siRNAs, the inhibitory effects on OSCC cell proliferation and apoptotic induction faded away. In conclusion, human plasma IgG, or IVIg against HER2 may be a promising agent for anti-OSCC therapy.

Common blind spots and interpretive errors of neck imaging

Complex anatomy and a wide spectrum of diseases in the head and neck predispose interpretation of neck imaging to cognitive pitfalls and perceptual errors. Extra attention to common blind spots in the neck and familiarity with common interpretive challenges could aid radiologists in preventing these diagnostic errors.

Cost-effectiveness of oral cancer screening approaches by visual examination: Systematic review

The present study is the first systematic review of papers that have performed a full economic evaluation on oral cancer screening strategies using visual oral examination. The review questions were (1) Is screening a cost-effective strategy in oral cancer? (2) What is the most cost-effective strategy among the different screening approaches in oral cancer? The main outcome measure was the incremental cost-effectiveness ratio. The study identifies and reviews seven full economic evaluations. The included studies scored 75%-100% on the methodological appraisal. Majority of the studies reports that oral cancer screening is a cost-effective strategy, especially in an opportunistic setting and high-risk subset of patients. The results were sensitive to cost and effectiveness parameters. Oral cancer screening, though found cost-effective, the uncertainty around these parameters necessitates additional studies that include better estimates in the modeling assessments. The heterogeneity in studies limited comparison and generalization.

Prediction of oral squamous cell carcinoma based on machine learning of breath samples: a prospective controlled study

Background

The aim of this study was to evaluate the possibility of breath testing as a method of cancer detection in patients with oral squamous cell carcinoma (OSCC).

Methods

Breath analysis was performed in 35 OSCC patients prior to surgery. In 22 patients, a subsequent breath test was carried out after surgery. Fifty healthy subjects were evaluated in the control group. Breath sampling was standardized regarding location and patient preparation. All analyses were performed using gas chromatography coupled with ion mobility spectrometry and machine learning.

Results

Differences in imaging as well as in pre- and postoperative findings of OSCC patients and healthy participants were observed. Specific volatile organic compound signatures were found in OSCC patients. Samples from patients and healthy individuals could be correctly assigned using machine learning with an average accuracy of 86–90%.

Conclusions

Breath analysis to determine OSCC in patients is promising, and the identification of patterns and the implementation of machine learning require further assessment and optimization. Larger prospective studies are required to use the full potential of machine learning to identify disease signatures in breath volatiles.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01862-z.

Identifying misconceptions about oral radiology and medicine among dental students

PURPOSE/OBJECTIVES

Misconceptions are learning deficiencies that can lead to inappropriate clinical decision-making in dental practice. Although misconceptions are common among students, they are rarely analyzed in dental education. Thus, this study aimed to identify and analyze students' misconceptions about oral radiology and medicine at a Brazilian dental school.

METHODS

Between October 2019 and March 2020, a self-administered anonymous questionnaire was distributed to dental students at the Federal University of Pernambuco, Brazil, which comprised multiple-choice questions about oral radiology and medicine. The questions were divided into two groups: 10 knowledge-based questions (less demand for reasoning) and five scenario-based questions (higher demand for reasoning). The students' responses were assessed for correctness (correct or incorrect) and confidence (sure or unsure), while misconceptions were identified when a student was sure of an incorrect response. Pearson's chi-square test was used to analyze the variables (α = 0.05).

RESULTS

A total of 1380 responses were collected. Misconceptions represented 24.3% (n = 336) of the total responses and 56.8% of the incorrect responses. The mean misconceptions per student were 3.7 (range, 0-8). Students who chose incorrect answers tended to have higher confidence levels (p < 0.001). Moreover, misconceptions were more frequent for scenario-based questions (25.7%) than for knowledge-based questions (23.7%) (p = 0.000).

CONCLUSION

A large number of misconceptions existed among participants. Our findings will aid educators and students in identifying misconceptions and planning measures to prevent and correct them.

Role of Artificial Intelligence in the Early Diagnosis of Oral Cancer. A Scoping Review

The early diagnosis of cancer can facilitate subsequent clinical patient management. Artificial intelligence (AI) has been found to be promising for improving the diagnostic process. The aim of the present study is to increase the evidence on the application of AI to the early diagnosis of oral cancer through a scoping review. A search was performed in the PubMed, Web of Science, Embase and Google Scholar databases during the period from January 2000 to December 2020, referring to the early non-invasive diagnosis of oral cancer based on AI applied to screening. Only accessible full-text articles were considered. Thirty-six studies were included on the early detection of oral cancer based on images (photographs (optical imaging and enhancement technology) and cytology) with the application of AI models. These studies were characterized by their heterogeneous nature. Each publication involved a different algorithm with potential training data bias and few comparative data for AI interpretation. Artificial intelligence may play an important role in precisely predicting the development of oral cancer, though several methodological issues need to be addressed in parallel to the advances in AI techniques, in order to allow large-scale transfer of the latter to population-based detection protocols.

Salvage surgery for patients with residual/persistent diseases after improper or insufficient treatment of oral squamous cell carcinoma: can we rectify these mistakes?

BACKGROUND

Patterns of failure after treatment of oral and squamous cell carcinomas (OSCC) are diversified, with recurrences being one of the common causes. A special group of patients are sometimes encountered in the outpatient clinic for improper or insufficient initial treatment with reports of positive margins, implying residual/persistent diseases. The question of whether these patients can be surgically salvaged remain unanswered.

METHODS

A retrospective study was performed between January 2013 and December 2017 for patients with residual or rapid recurrent (within 3 months) OSCCs, who received salvage surgeries in our institution. The patients with residual/persistent OSCCs were those with microscopic or macroscopic positive surgical margins, while those with rapid recurrent OSCCs were those with close or negative margins, but unabated painful symptoms right after treatment. Both clinicopathological and prognostic variables were analyzed. The focus was also directed towards lessons for possible initial mistakes, resulting in these residual/persistent diseases.

RESULTS

Of 103 patients, 68 (66%) were men, with mean age of 56.3 years. The overall survival reached 60.2%. Regarding the primary OSCC status, most of our patients (n = 75, 72.8%) were diagnosed with ycT2-3 stages. Besides, most patients were found with macroscopic residual diseases (52.4%) before our salvage surgery. The sizes of the residual/persistent OSCCs were generally under 4 cm (87.3%) with minimally residual in 21 (20.4%). Among all the variables, primary T stage (p = 0.003), and residual lesion size (p < 0.001) were significantly associated with the prognosis in multivariate analysis. Though the causes for the initial surgical failure were multifactorial, most were stemmed from poor planning and unstandardized execution.

CONCLUSIONS

Cases with residual/persistent OSCCs were mostly due to mistakes which could have been avoided under well-round treatment plans and careful surgical practice. Salvage surgery for cases with smaller residual/persistent OSCCs is still feasible with acceptable outcomes.

Effect of Human Development Index and other socioeconomic factors on mortality-to-incidence ratio of lips and oral cavity cancer in Mexican states: an ecological study

OBJECTIVES

To assess the association between the Human Development Index (HDI) and covariates on the mortality-to-incidence ratio (MIR) of lips and oral cavity cancer (LOCC) in Mexico.

DESIGN

Ecological study.

SETTING

Data from 32 Mexican states for year 2019.

PARTICIPANTS

Data set of male and female populations from Mexico.

EXPOSURES

Socioeconomic conditions based on HDI and covariates related to healthcare system capacity (total health spending per capita, school dropout and ratio of medical personnel in direct contact with patients).

PRIMARY AND SECONDARY OUTCOME MEASURES

MIR of LOCC by state and sex was calculated from the Global Burden of Disease Study website for year 2019. Data for calculating HDI 2019 by state and covariates were obtained from the National Institute of Statistics and Geography. A multiple regression model was constructed to measure the effects of HDI and covariates on LOCC-MIR.

RESULTS

Among the states with the highest HDI (>0.780), Colima had the highest aged-standardised rates per 100.000 in men for incidence (5.026) and mortality (3.118). The greatest burden of the disease was found on men, with the highest Men:Women MIR in Colima (3.10) and Baja California Sur (2.73). The highest MIR (>0.65) was found among the states with the lowest HDI (Oaxaca and Chiapas). For each unit of increase of the HDI there was a decrease in the LOCC- MIR of -0.778, controlling for the covariates. The most suitable regression model explained the 57% (F (p): 0.000) of the variance.

CONCLUSIONS

Men were most affected by LOCC in Mexican states. The highest MIRs of LOCC were found in the states with the highest HDI. But a worse prognosis of the disease, expressed as a higher MIR, is expected in contexts with lower HDI in the country, even with lower MIRs.

Serum HSP90-Alpha and Oral Squamous Cell Carcinoma : A Prospective Biomarker

AIM

Current study aims to perform differential protein expression analysis of serum samples from Oral squamous cell carcinoma (OSCC) patients and healthy controls in search of potential diagnostic and/or prognostic biomarker(s).

OBJECTIVE

OSCC is diagnosed late, resulting in poor survival and high mortality. Identification of non-invasive prognostic biomarker is of utmost importance for early diagnosis and proper management of the disease; hence we used proteomic approach to identify potential biomarkers from serum.

METHODS

Serum samples (OSCC n=45 and control n=30) were depleted and proteins were separated using 2-D gel electrophoresis followed by identification by mass spectrometric analysis. Gene expression analysis of identified proteins in malignant and normal tissue was also performed to complement proteomics studies.

RESULTS

Among differentially expressed proteins, a noteworthy observation was up regulation of Heat shock protein alpha (HSP90α) from serum of oral cancer patients. We also observed elevated levels of Haptoglobin (HP) along with down regulation of Type II keratin cytoskeletal 1(KRT1) and serum Albumin (ALB) in oral cancer patients. Gene expression studies of identified proteins in malignant and normal tissue revealed a similar pattern with the exception of KRT1. We believe that elevated levels of serum HSP90 alpha might be used as a potential biomarker.

CONCLUSION

Our findings suggest the contribution of HSP90 alpha and other identified proteins in oral pathology as pro/anti apoptotic modulators, thus they are being considered as predictive biomarkers.

Oral Squamous Cell Carcinoma Bone Invasion: Possible Roles of E-Cadherin in Osteoclastogenesis and Bone Infiltration

INTRODUCTION

Squamous cell carcinoma is the most common cancer of the oral cavity. When the tumor invades the bone tissue, the prognostic and survival rates decrease a lot, and the treatment becomes more aggressive, with several damages to the patient and health system. Many of the molecular mechanisms of bone invasion process are not understood yet, but it is already known that one of central processes of tumor evolution - adjacent tissues invasion and metastasis - is a large spectrum of phenotypic changes in epithelial cells to mesenchymal, in a process named as epithelial-mesenchymal transition (EMT). Loss of E-cadherin, an important epithelial cell adhesion protein, is a hallmark of this phenomenon. The objective of this retrospective study is to evaluate the expression of E-cadherin protein, comparing its distribution with clinical characteristics of the patients and possibly relation to EMT.

METHODS

Sixty-two cases with respective clinical data were analyzed by comparing immunohistochemical, H and E staining, and clinical data, observing the tumor-bone interface (TBI) and the surrounding tumor that had no direct contact with the bone surface (ST).

RESULTS

Forty cases were positive for E-cadherin (64%) with a heterogeneous pattern. Statistical analysis showed a significant difference between the presence of E-cadherin expression and tobacco smokers. Also, the equal or weaker protein expression in the ST than TBI is related to a worse overall survival. No statistically significant difference in other prognostic factors was observed.

CONCLUSION

Our results suggest that the tumor cells that interact with the bone tissue could gain molecular changes, like partial EMT and osteoclastogenesis induction, which facilitate their migration and increase the bone resorption, resulting in a worse patient's prognosis.

The hidden curve behind COVID-19 outbreak: the impact of delay in treatment initiation in cancer patients and how to mitigate the additional risk of dying-the head and neck cancer model

PURPOSE

The rapid spread of the SARS-CoV-2 pandemic around the world caused most healthcare services to turn substantial attention to treatment of these patients and also to alter the structure of healthcare systems to address an infectious disease. As a result, many cancer patients had their treatment deferred during the pandemic, increasing the time-to-treatment initiation, the number of untreated patients (which will alter the dynamics of healthcare delivery in the post-pandemic era) and increasing their risk of death. Hence, we analyzed the impact on global cancer mortality considering the decline in oncology care during the COVID-19 outbreak using head and neck cancer, a known time-dependent disease, as a model.

METHODS

An online practical tool capable of predicting the risk of cancer patients dying due to the COVID-19 outbreak and also useful for mitigation strategies after the peak of the pandemic has been developed, based on a mathematical model. The scenarios were estimated by information of 15 oncological services worldwide, given a perspective from the five continents and also some simulations were conducted at world demographic data.

RESULTS

The model demonstrates that the more that cancer care was maintained during the outbreak and also the more it is increased during the mitigation period, the shorter will be the recovery, lessening the additional risk of dying due to time-to-treatment initiation.

CONCLUSIONS

This impact of COVID-19 pandemic on cancer patients is inevitable, but it is possible to minimize it with an effort measured by the proposed model.

Saliva Gene Promoter Hypermethylation as a Biomarker in Oral Cancer

Oral carcinogenesis is a multistep process characterized by a summation of multiple genetic and epigenetic alterations in key regulatory genes. The silencing of genes by aberrant promoter hypermethylation is thought to be an important epigenetic event in cancer development and progression which has great potential as a biomarker for early diagnosis, tumor molecular subtyping, prognosis, monitoring, and therapy. Aberrant DNA methylation has been detected in different liquid biopsies, which may represent a potential alternative to solid biopsies. The detection of methylated genes in saliva may have clinical application for noninvasive oral cancer screening and early diagnosis. Here, we review the current evidence on gene promoter hypermethylation in saliva.

Time-to-Treatment in Oral Cancer: Causes and Implications for Survival

The purpose of this review was to identify and describe the causes that influence the time-intervals in the pathway of diagnosis and treatment of oral cancer and to assess its impact on prognosis and survival. The review was structured according to the recommendations of the Aarhus statement, considering original data from individual studies and systematic reviews that reported outcomes related to the patient, diagnostic and pre-treatment intervals. The patient interval is the major contributor to the total time-interval. Unawareness of signs and/or symptoms, denial and lack of knowledge about oral cancer are the major contributors to the process of seeking medical attention. The diagnostic interval is influenced by tumor factors, delays in referral due to higher number of consultations and previous treatment with different medicines or dental procedures and by professional factors such as experience and lack of knowledge related to the disease and diagnostic procedures. Patients with advanced stage disease, primary treatment with radiotherapy, treatment at an academic facility and transitions in care are associated with prolonged pre-treatment intervals. An emerging body of evidence supports the impact of prolonged pre-treatment and treatment intervals with poorer survival from oral cancer.

The contribution of artificial intelligence to reducing the diagnostic delay in oral cancer

Oral cancer (OC) is the sixth most commonly reported malignant disease globally, with high rates of disease-related morbidity and mortality due to advanced loco-regional stage at diagnosis. Early detection and prompt treatment offer the best outcomes to patients, yet the majority of OC lesions are detected at late stages with 45% survival rate for 2 years. The primary cause of poor OC outcomes is unavailable or ineffective screening and surveillance at the local point-of-care level, leading to delays in specialist referral and subsequent treatment. Lack of adequate awareness of OC among the public and professionals, and barriers to accessing health care services in a timely manner also contribute to delayed diagnosis. As image analysis and diagnostic technologies are evolving, various artificial intelligence (AI) approaches, specific algorithms and predictive models are beginning to have a considerable impact in improving diagnostic accuracy for OC. AI based technologies combined with intraoral photographic images or optical imaging methods are under investigation for automated detection and classification of OC. These new methods and technologies have great potential to improve outcomes, especially in low-resource settings. Such approaches can be used to predict oral cancer risk as an adjunct to population screening by providing real-time risk assessment. The objective of this study is to (1) provide an overview of components of delayed OC diagnosis and (2) evaluate novel AI based approaches with respect to their utility and implications for improving oral cancer detection.

Treatment delay in early-stage oral squamous cell carcinoma and its relation to survival

The aim of this study was to investigate the impact of a prolonged treatment delay on survival in patients with primary oral squamous cell carcinoma. The investigators hypothesized that treatment delay affects survival, supposing a poor outcome in patients with prolonged treatment initiation. In addition, a critical treatment delay should be defined. Inclusion criteria were a histopathological diagnosis of primary squamous cell carcinoma of the oral cavity and a surgery-based treatment of the tumor. Patients with a history of previously diagnosed malignancies and patients with distant metastasis at the time of diagnosis were excluded from this protocol. Common clinical and histopathological data were assessed retrospectively. Treatment delay was analyzed for the interval between initial presentation and the date of surgery. A total of 484 patients could be included. Considering early-stage patients, the risk of death increases by 1.8% for each day that the treatment delay is prolonged if all other characteristics do not change (p = 0.0035). In patients with advanced disease, a prolonged treatment delay does not affect the risk of death (p = 0.9134). In terms of progression-free survival, treatment delay tends to be associated with a higher risk of recurrence in early-stage disease, but without being statistically significant (p = 0.0718). For patients with early-stage disease, a treatment delay of 20 days is critical regarding overall survival (p = 0.011). For patients with advanced-stage disease, no significant differences have been observed. As patients with early-stage oral squamous cell carcinoma profit from early treatment initiation, we suggest an acceptable maximum treatment delay of no more than 20 days in the surgical management of these patients.

Salivary Micro-RNA and Oral Squamous Cell Carcinoma: A Systematic Review

Oral squamous cell carcinoma (OSCC) is a widespread malignancy with high mortality. In particular, a delay in its diagnosis dramatically decreases the survival rate. The aim of this systematic review was to investigate and summarize clinical results in the literature, regarding the potential use of salivary microRNAs (miRNAs) as diagnostic and prognostic biomarkers for OSCC patients. Twelve papers were selected, including both case-control and cohort studies, and all of them detected significantly dysregulated miRNAs in OSCC patients compared to healthy controls. Based on our results, salivary miRNAs might provide a non-invasive and cost-effective method in the diagnosis of OSCC, and also to monitor more easily its evolution and therapeutic response and therefore aid in the establishment of specific therapeutic strategies.

Triptolide suppresses oral cancer cell PD-L1 expression in the interferon-γ-modulated microenvironment in vitro, in vivo, and in clinical patients

Biological and prognostic roles of programmed death ligand 1 (PD-L1) remain unclear in oral squamous cell carcinoma (OSCC). Moreover, the pivotal role of tumor microenvironmental interferon-gamma (IFN-γ) in host responses to malignant cells, oral cancer growth, and PD-L1 expression has not been adequately studied. Thus, PD-L1 expression in 130 OSCC samples was analyzed using immunohistochemistry, which was found significantly overexpressed at the tumor site (P <  .01). We further analyzed the effects of IFN-γ on OSCC cell proliferation using enzyme-linked immunosorbent assays and found that IFN-γ drives PD-L1 expression in OSCC cells in a dose-dependent manner. Triptolide (TPL), a bioactive compound isolated from Tripterygium wilfordii, exhibits anti-inflammatory and antitumor activities. To investigate whether the antitumor effect of TPL involves the suppression of PD-L1 expression, we treated OSCC cells in vitro and a patient-derived tumor xenograft (PDTX) model with TPL. TPL suppressed PD-L1 expression in the PDTX model, inhibiting tumor growth, and in OSCC cells in an IFN-γ-modulated microenvironment. We concluded that TPL inhibits tumor growth in oral cancer and downregulates PD-L1 expression in oral cancer cells in vitro. Our results provide evidence for the clinical development of PD-L1-targeted therapy for OSCC.

The G-Protein Coupled Formyl Peptide Receptors and Their Role in the Progression of Digestive Tract Cancer

Chronic inflammation is a causative factor of many cancers, although it originally acts as a protective host response to the loss of tissue homeostasis. Many inflammatory conditions predispose susceptible cells, most of which are of epithelial origin, to neoplastic transformation. There is a close correlation between digestive tract (DT) cancer and chronic inflammation, such as esophageal adenocarcinoma associated with Barrett’s esophagus, helicobacter pylori infection as the cause of stomach cancer, hepatitis leading to liver cirrhosis and subsequent cancer, and colon cancer linking to inflammatory bowel diseases and schistosomiasis. A prominent feature of malignant transformation of DT tract epithelial cells is their adoption of somatic gene mutations resulting in abnormal expression of proteins that endow the cells with unlimited proliferation as well as increased motility and invasive capabilities. Many of these events are mediated by Gi-protein coupled chemoattractant receptors (GPCRs) including formyl peptide receptors (FPRs in human, Fprs in mice). In this article, we review the current understanding of FPRs (Fprs) and their function in DT cancer types as well as their potential as therapeutic targets.

Prognostic factors analysis for oral cavity cancer survival in the Netherlands and Taiwan using a privacy-preserving federated infrastructure

The difference in incidence of oral cavity cancer (OCC) between Taiwan and the Netherlands is striking. Different risk factors and treatment expertise may result in survival differences between the two countries. However due to regulatory restrictions, patient-level analyses of combined data from the Netherlands and Taiwan are infeasible. We implemented a software infrastructure for federated analyses on data from multiple organisations. We included 41,633‬ patients with single-tumour OCC between 2004 and 2016, undergoing surgery, from the Taiwan Cancer Registry and Netherlands Cancer Registry. Federated Cox Proportional Hazard was used to analyse associations between patient and tumour characteristics, country, treatment and hospital volume with survival. Five factors showed differential effects on survival of OCC patients in the Netherlands and Taiwan: age at diagnosis, stage, grade, treatment and hospital volume. The risk of death for OCC patients younger than 60 years, with advanced stage, higher grade or receiving adjuvant therapy after surgery was lower in the Netherlands than in Taiwan; but patients older than 70 years, with early stage, lower grade and receiving surgery alone in the Netherlands were at higher risk of death than those in Taiwan. The mortality risk of OCC in Taiwanese patients treated in hospitals with higher hospital volume (≥ 50 surgeries per year) was lower than in Dutch patients. We conducted analyses without exchanging patient-level information, overcoming barriers for sharing privacy sensitive information. The outcomes of patients treated in the Netherlands and Taiwan were slightly different after controlling for other prognostic factors.

A deep learning algorithm for detection of oral cavity squamous cell carcinoma from photographic images: A retrospective study

BACKGROUND

The overall prognosis of oral cancer remains poor because over half of patients are diagnosed at advanced-stages. Previously reported screening and earlier detection methods for oral cancer still largely rely on health workers' clinical experience and as yet there is no established method. We aimed to develop a rapid, non-invasive, cost-effective, and easy-to-use deep learning approach for identifying oral cavity squamous cell carcinoma (OCSCC) patients using photographic images.

METHODS

We developed an automated deep learning algorithm using cascaded convolutional neural networks to detect OCSCC from photographic images. We included all biopsy-proven OCSCC photographs and normal controls of 44,409 clinical images collected from 11 hospitals around China between April 12, 2006, and Nov 25, 2019. We trained the algorithm on a randomly selected part of this dataset (development dataset) and used the rest for testing (internal validation dataset). Additionally, we curated an external validation dataset comprising clinical photographs from six representative journals in the field of dentistry and oral surgery. We also compared the performance of the algorithm with that of seven oral cancer specialists on a clinical validation dataset. We used the pathological reports as gold standard for OCSCC identification. We evaluated the algorithm performance on the internal, external, and clinical validation datasets by calculating the area under the receiver operating characteristic curves (AUCs), accuracy, sensitivity, and specificity with two-sided 95% CIs.

FINDINGS

1469 intraoral photographic images were used to validate our approach. The deep learning algorithm achieved an AUC of 0·983 (95% CI 0·973-0·991), sensitivity of 94·9% (0·915-0·978), and specificity of 88·7% (0·845-0·926) on the internal validation dataset (n = 401), and an AUC of 0·935 (0·910-0·957), sensitivity of 89·6% (0·847-0·942) and specificity of 80·6% (0·757-0·853) on the external validation dataset (n = 402). For a secondary analysis on the internal validation dataset, the algorithm presented an AUC of 0·995 (0·988-0·999), sensitivity of 97·4% (0·932-1·000) and specificity of 93·5% (0·882-0·979) in detecting early-stage OCSCC. On the clinical validation dataset (n = 666), our algorithm achieved comparable performance to that of the average oral cancer expert in terms of accuracy (92·3% [0·902-0·943] vs 92.4% [0·912-0·936]), sensitivity (91·0% [0·879-0·941] vs 91·7% [0·898-0·934]), and specificity (93·5% [0·909-0·960] vs 93·1% [0·914-0·948]). The algorithm also achieved significantly better performance than that of the average medical student (accuracy of 87·0% [0·855-0·885], sensitivity of 83·1% [0·807-0·854], and specificity of 90·7% [0·889-0·924]) and the average non-medical student (accuracy of 77·2% [0·757-0·787], sensitivity of 76·6% [0·743-0·788], and specificity of 77·9% [0·759-0·797]).

INTERPRETATION

Automated detection of OCSCC by deep-learning-powered algorithm is a rapid, non-invasive, low-cost, and convenient method, which yielded comparable performance to that of human specialists and has the potential to be used as a clinical tool for fast screening, earlier detection, and therapeutic efficacy assessment of the cancer.

The impact of delayed diagnosis on the outcomes of oral cancer patients: a retrospective cohort study

The contemporary literature is discordant regarding the role of delayed diagnosis in the prognosis of patients with oral cancer. This study examined data on a previously reported cohort of 101 patients with oral squamous cell carcinoma diagnosed at a single institution between 2008 and 2010. The time interval between symptom onset and initial histological diagnosis (diagnostic delay) was recorded for each patient, as were demographic data and cancer features such as T stage, nodal status, and smoking status. The mean follow-up period was 4 years 10 months. The mean diagnostic delay was 4 months, mean overall survival was 5years 6 months, and mean disease-specific survival was 4 years 9 months. No significant correlation was found between diagnostic delay and overall survival, disease-specific survival, or recurrence rates. Patients with node-positive disease were more likely to be diagnosed earlier, whereas women and non-smokers were more likely to have a delayed diagnosis. Inherent tumour biology is likely an important prognostic factor separate to diagnostic delay. Public education efforts should focus on symptom recognition and encourage early presentation for investigation of oral lesions, particularly for females and non-smokers, so that more aggressive tumours can be treated sooner to give the best chance at survival.

Relationship between the Human Development Index and its Components with Oral Cancer in Latin America

To evaluate the relationship between the Human Development Index (HDI) and its components with oral cancer (OC) in Latin America. Ecological study in 20 Latin American countries in 2010 and 2017, which evaluated the relationship between the Age-Standardized Rates (ASRs) of incidence and mortality from oral cancer and the following indicators: HDI, with its components (income, education, and health indexes); and the Gini and Theil-L indexes. Among the countries with the highest HDI, men from Brazil and Cuba had the highest incidence and mortality ASRs per 100,000 inhabitants (ASR incidence >7.5 and mortality >4.5). Among those with the lowest HDI, Haiti was the most affected country (ASR incidence >4.1 and mortality >3.0). The highest male:female ratio was in Paraguay in both years (incidence >3.5 and mortality >4.0). Mortality from oral cancer is negatively related to the global HDI in both years, with regression coefficients (95% confidence interval) being −5.78 (−11.77, 0.20) in 2010 and −5.97 (−11.38, −0.56) in 2017; and separate (independent) from the income [−4.57 (−9.92, 0.77) in 2010 and −4.84 (−9.52, −0.17) in 2017] and health indexes [−5.81 (−11.10, −0.52) and −6.52 (−11.32, −1.72) in 2017] (p < 0.05) in the countries with lower HDI. Oral cancer incidence and mortality rates vary both among and within Latin American countries according to sex, with a greater burden on men. The HDI is negatively related to mortality from oral cancer in the countries of medium and low HDI.

Isoform specific FBXW7 mediates NOTCH1 Abruptex mutation C1133Y deregulation in oral squamous cell carcinoma

Our group previously identified that the NOTCH1 Abruptex domain contains the most mutations in Chinese OSCC patients, including a hotspot mutation (C1133Y). FBXW7 is an E3 ubiquitin ligase that regulates a network of proteins, including NOTCH1, via degradation. In this study, we first described the co-localization of isoform specific FBXW7-FBXW7β and NOTCH1^C1133Y mutation in the same cytoplasmic sites. Gain- and loss-of-function assays were performed to examine the tumor suppressor role of FBXW7β in the proliferation and invasion of OSCC cells. The co-expression of NOTCH1^C1133Y and FBXW7β significantly attenuated tumor growth. Meanwhile, FBXW7β reversed the oncogenic phenotype and the activation of the AKT/ERK/NFκB pathway induced by NOTCH1^C1133Y mutation. FBXW7β downregulated the stability of NOTCH1^C1133Y protein and promoted protein ubiquitination. This was the first time that we selected a NOTCH1 hotspot mutation detected in clinical samples and identified the function of FBXW7β that mediated NOTCH1 mutation degradation in OSCC. The newly identified interaction between FBXW7β and NOTCH1^C1133Y protein provides new insights into the progression of OSCC, especially regarding Abruptex domain mutations, and represents a valuable target for OSCC therapy.

Metastasis of oral squamous cell carcinoma to the parotid lymph nodes

Parotid lymph node (PLN) metastasis greatly worsens the prognosis of patients with oral squamous cell carcinoma (OSCC) and poses a great challenge for further treatment of OSCC. The clinicopathological characteristics and treatment strategies for PLN metastasis from OSCC need to be comprehensively elucidated. A retrospective review of OSCC patients who experienced postoperative PLN metastasis in our department between 2000 and 2018 was performed in this study. A total of 47 OSCC patients with postoperative PLN metastasis were identified. PLN with metastasis were divided into three groups based on the location: parotid tail (PLN-t), superficial lobe (PLN-sl), and deep lobe (PLN-dl). Most of the patients experienced PLN metastasis within less than 12 months after the primary surgery for OSCC. Comparatively, patients with PLN-sl metastasis were more prone to have infiltration of the facial nerve. The tongue and buccal mucosa were the most frequent primary sites associated with PLN metastasis from OSCC. PLNs in the parotid tail were most commonly affected by the metastasized OSCC. Consequently, we recommend a series of strategies for the prevention and treatment of PLN metastasis for OSCC patients. In conclusion, PLNs should not be overlooked during preoperative evaluation and postoperative follow-up examinations for OSCC patients.

Prognostic factors associated with overall survival in patients with oral cavity squamous cell carcinoma

Background

Low socioeconomic status, increasing age, and poor lifestyle behaviors are associated with poor survival in patients with oral cavity squamous cell carcinoma (OCSCC). To determine the overall survival (OS) and the risk of OCSCC death by tumor subsite.

Material and Methods

A retrospective cohort study of OCSCC patients diagnosed from 2007 to 2009 and treated at a single cancer center in Rio de Janeiro, Brazil. Patient information was obtained from the Hospital Cancer Registry (HCR) database and complemented by individual search of physical and electronic medical records. Descriptive statistics of population characteristics were computed. OS was estimated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards regression analyses were used to estimate the risk of death by tumor subsite.

Results

Seven hundred and three patients with OCSCC were identified. Most patients were men (77.4%) with low levels of education (67.5%), who drank (73.9%) and smoked (79.7%). The most prevalent tumor site was the tongue (45.4%), 73.4% of patients had advanced (clinical stage III or IV) OCSCC at diagnosis and 74.1% died during follow-up. For the entire cohort, the OS was 39.1% at two years and 27.9% at five years. The median survival time was 1.4 years (95%CI: 1.2‒1.5). Non-operative treatment (HR: 3.11; 95%CI: 2.26‒4.29; p <0.001), advanced stage (HR 2.14; 95%CI 1.68-2.74; p <0.001), and age >60 years at diagnosis (HR: 1.37; 95%CI: 1.15‒1.64; p <0.001) were independently associated with the risk of death. However, these factors varied by tumour subsite.

Conclusions

Analysis of specific subsites of the oral cavity revealed substantial differences in prognostic factors associated with poor survival in OCSCC.

Key words:Squamous cell carcinoma, oral cavity cancer, survival, prognosis.

Nanophotosensitizers for Folate Receptor-Targeted and Redox-Sensitive Delivery of Chlorin E6 against Cancer Cells

In this study, FA-PEG₃₅₀₀-ss-Ce6tri copolymer was synthesized to deliver photosensitizers via redox-sensitive and folate receptor-specific manner. Folic acid (FA) was attached to amine end of poly (ethylene glycol) (PEG₃₅₀₀) (FA-PEG₃₅₀₀ conjugates) and cystamine-conjugated chlorin e6 (Ce6) (Ce6-cystamine conjugates). FA-PEG₃₅₀₀ was further conjugated with Ce6-cystamine to produce FA-PEG₃₅₀₀-ss-Ce6 conjugates. To the remaining amine end group of Ce6-cystamine conjugates, Ce6 was attached to produce FA-PEG₃₅₀₀-ss-Ce6tri. Nanophotosensitizers of FA-PEG₃₅₀₀-ss-Ce6tri copolymer were smaller than 200 nm. Their shapes were disintegrated by treatment with GSH and then Ce6 released by GSH-dependent manner. Compared to Ce6 alone, FA-PEG₃₅₀₀-ss-Ce6tri copolymer nanophotosensitizers recorded higher Ce6 uptake ratio, reactive oxygen species (ROS) production and cellular cytotoxicity against KB and YD-38 cells. The in vitro and in vivo study approved that delivery of nanophotosensitizers is achieved by folate receptor-sensitive manner. These results indicated that FA-PEG₃₅₀₀-ss-Ce6tri copolymer nanophotosensitizers are superior candidate for treatment of oral cancer.

Diagnostic delay for head and neck cancer in South India: A Mixed-methods Study

Background:

Early diagnosis is an important aspect of quality of cancer care.Analysis of the diagnostic delays and the reasons for delay helps to plan strategies to improve cancer care.

Objectives:

To determine the primary, secondary, and total diagnostic delay of patients diagnosed with head and neck cancer and to explore the reasons for the delay from the patient perspective.

Methods:

Explanatory mixed method design was used. Two hundred persons with a confirmed diagnosis of head and neck cancer attending the ENT (ear, nose, throat) cancer clinic in a teaching hospital before the initiation of treatment were included in the study. The median delay and the association of the delay with the various factors were analyzed. Sixteen one-to-one interviews of patients were done to identify the reasons for the delays from the patient perspective.

Results:

Median primary, secondary, and total diagnostic delays were 30 days, 30 days, and 73 days, respectively. Statistically, primary delay was found significantly longer among ever users of smokeless tobacco and significantly longer secondary delay was found among those with age less than 60 years. The reasons for the delay were grouped in the categories (i) Symptom appraisal delay due to low perceived seriousness and (ii) health-seeking behavior delay.

Conclusions:

The diagnostic delay was considerable. Measures to enhance symptom appraisal by improving health literacy, opportunistic screening, and strengthening the referral system would decrease diagnostic delay.

Overall time interval ("Total diagnostic delay") and mortality in symptomatic oral cancer: A U-shaped association

OBJECTIVES

To assess the impact on survival of the total time interval since the first bodily change (sign/symptom) until the start of treatment in symptomatic oral cancer patients.

METHODS

Retrospective, hospital-based study designed within the "Aarhus Statement" conceptual framework, using the overall interval to treatment of 183 oral cancer patients to analyse their survival rates.

RESULTS

Overall time interval (T5): 107.1 ± 85.2 days. Overall survival rate: 58.4 (CI: 51.3-66.4%). Recurrence time (median): 724 days (IQR, 223-2963.5). Median survival time: 1744 days (IQR, 479.5-3438). Overall delay (T5) and mortality showed a U-shaped association, where patients with short (24.0-55.5 days) and long T5 intervals (127.5-420 days) had higher mortality than those with medium T5 intervals (55.5-127.5 days).

CONCLUSION

There is a non-monotonic association between time interval and mortality. Higher mortality rates are linked to shorter and longer time intervals. This may induce underestimation of the association when time intervals are considered dichotomously.

Awareness on oral cancer among patients attending dental school clinics in Brazil

Background

Oral cancer is considered a public health problem worldwide. Dental schools may play an important role in educating patients about oral cancer. This study aimed at evaluating the knowledge of patients attending clinics at two dental schools in Brazil.

Material and Methods

From March 2017 to April 2017, 251 patients who were attending clinics at two dental schools in Recife, Brazil, were included in the study. Patients were contacted in the waiting rooms of the clinic. Each participant completed a self-administered questionnaire, which consists of 21 questions, including socio-demographic and specific information on the disease. Data were analyzed using descriptive statistics, and a chi-square test (with a 5% significance level) was used to assess the correlation between the variables, education and family income and other variables.

Results

Most participants were women (64.9%) with a mean age of 42.72 years. Most participants were knowledgeable about oral cancer and identified tobacco use (48.6%), alcohol consumption (25.1%), and solar radiation (12%) as the primary risk factors for the disease. Only 36.7% of the participants reported having received counselling on oral cancer, of which 18.3% received the information from a dentist. All patients with an income higher than six minimum wages were aware about oral cancer (p = 0.001).

Conclusions

These findings emphasize the importance of educational programs in dental schools as well providing integrated services for patients seeking care at school clinics, including population’s awareness on oral cancer.

Key words:Dental school, knowledge, oral cancer, oral health education, patient education.

Cell-Free microRNAs as Potential Oral Cancer Biomarkers: From Diagnosis to Therapy

Oral cavity cancer is the most frequent malignancy of the head and neck. Unfortunately, despite educational interventions for prevention and early diagnosis, oral cancer patients are often diagnosed in advanced stages associated with poor prognosis and life expectancy. Therefore, there is an urgent need to find noninvasive biomarkers to improve early detection of this tumor. Liquid biopsy has emerged as a valuable tool in medical oncology which provides new horizons for improving clinical decision making. Notably, cell-free microRNAs (miRNAs), a class of short non-coding RNAs, are emerging as novel noninvasive cancer biomarkers. Here, we provide an overview of the potential clinical application of cell-free miRNAs as diagnostic, prognostic, and therapeutic biomarkers in oral cancer.

miRNAs in liquid biopsy for oral squamous cell carcinoma diagnosis: Systematic review and meta-analysis

Oral squamous cell carcinoma (OSCC) is often diagnosed at advanced stages and is associated with poor survival rates. Increasing evidence suggests that microRNAs (miRNAs) present in liquid biopsies could be potential biomarkers for non-invasive OSCC diagnosis. Here, we performed a comprehensive meta-analysis to evaluate the overall diagnostic accuracy of blood and salivary miRNAs in detecting OSCC. A literature search using PubMed EMBASE, Web of Science, LILACS, Scopus, and the Cochrane Library was undertaken up to February 2019. Study quality was assessed with the Quality Assessment for Studies of Diagnostic Accuracy-2, and sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and their corresponding 95% confidence intervals (CIs) were calculated using a bivariate random-effect meta-analysis model. Meta-regression and subgroup analyses were performed to assess the heterogeneity. Twenty-five study units from 16 articles with 2562 subjects were included in this meta-analysis. The pooled sensitivity and specificity of blood and salivary miRNAs in the diagnosis of OSCC were 0.78 (95% CI: 0.76-0.80) and 0.82 (95% CI: 0.79-0.84), respectively, and the pooled positive and negative likelihood ratios were 4.31 (95% CI: 3.38-5.51) and 0.25 (95% CI: 0.20-0.32), respectively. The overall area under the curve was 0.91 (95% CI: 0.88-0.93), with a diagnostic odds ratio of 21.46 (95% CI: 13.37-34.45). These findings provide evidence regarding the potential clinical application of blood and salivary miRNAs as a novel, non-invasive, and accurate diagnostic tool for OSCC.