Risk-based oral cancer screening - lessons to be learnt

Risk Prediction Models for Oral Cancer: A Systematic Review

In the last 30 years, there has been an increasing incidence of oral cancer worldwide. Earlier detection of oral cancer has been shown to improve survival rates. However, given the relatively low prevalence of this disease, population-wide screening is likely to be inefficient. Risk prediction models could be used to target screening to those at highest risk or to select individuals for preventative interventions. This review (a) systematically identified published models that predict the development of oral cancer and are suitable for use in the general population and (b) described and compared the identified models, focusing on their development, including risk factors, performance and applicability to risk-stratified screening. A search was carried out in November 2022 in the Medline, Embase and Cochrane Library databases to identify primary research papers that report the development or validation of models predicting the risk of developing oral cancer (cancers of the oral cavity or oropharynx). The PROBAST tool was used to evaluate the risk of bias in the identified studies and the applicability of the models they describe. The search identified 11,222 articles, of which 14 studies (describing 23 models), satisfied the eligibility criteria of this review. The most commonly included risk factors were age (n = 20), alcohol consumption (n = 18) and smoking (n = 17). Six of the included models incorporated genetic information and three used biomarkers as predictors. Including information on human papillomavirus status was shown to improve model performance; however, this was only included in a small number of models. Most of the identified models (n = 13) showed good or excellent discrimination (AUROC > 0.7). Only fourteen models had been validated and only two of these validations were carried out in populations distinct from the model development population (external validation). Conclusions: Several risk prediction models have been identified that could be used to identify individuals at the highest risk of oral cancer within the context of screening programmes. However, external validation of these models in the target population is required, and, subsequently, an assessment of the feasibility of implementation with a risk-stratified screening programme for oral cancer.

Methods, Detection Rates, and Survival Outcomes of Screening for Head and Neck Cancers: A Systematic Review

Importance

Head and neck cancers (HNCs) are often diagnosed at advanced clinical stages during their symptomatic phase, leading to a reduced treatment window and poor survival. Screening programs have been suggested as a mitigation strategy.

Objective

To examine the effectiveness of current HNC screening programs in improving diagnosis and survival in adults.

Evidence Review

This Preferred Reporting Items for Systematic Reviews and Meta-analyses-guided systematic review involved use of peer-reviewed, English-language journal articles identified from MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials between January 1, 2001, and July 15, 2022. Snowballing was applied to retrieve more studies. Eligible articles were original clinical trials and observational studies presenting a universal or risk-targeted screening program of primary HNC in the adult population. Reporting quality was assessed using the JBI's critical appraisal tools.

Findings

Database searches yielded 3646 unique citations with an additional 8 studies found via snowballing. Five reviewers assessed the full text of 106 studies. Sixteen articles were ultimately included in the review, involving 4.7 million adults (34.1%-100% male; median age, 30-59 years). Fifteen studies were based in Asia and 1 in Europe (Portugal). Five reported data from randomized clinical trials. An oral inspection conducted once or once every 2 to 3 years was described in 11 studies for screening oral cancer, while multistep screening involving Epstein-Barr virus serologic testing for nasopharyngeal carcinoma delivered every 1 to 4 years was presented in 5. In 4 trials and 6 observational studies, screening significantly increased the detection of localized (stage I/II) tumor or was associated with an increased proportion of diagnoses, respectively, regardless of the population and cancer subsites. Universal screening of asymptomatic adults improved 3- to 5-year overall survival but did not increase cancer-specific survival in 4 trials. Targeted screening improved overall and cancer-specific survival or was associated with improved survival outcomes in 2 trials and 2 observational studies, respectively. Studies had low to medium risks of bias.

Conclusions and Relevance

Evidence from the existing literature suggests that a risk-targeted screening program for oral and nasopharyngeal cancers could improve diagnosis and patient survival. Screening adherence, societal cost-effectiveness, and optimal risk stratification of such a program warrant future research, especially in low-incidence settings outside Asia.

Oral cancer screening knowledge and practices among dental professionals at the University of Toronto

INTRODUCTION

Opportunistic oral cancer screening during visits to the dentist is a non-invasive and accessible option for detection of pre-malignant lesions and early-stage malignancies. The objective of this study was to investigate the knowledge, practices, and attitudes towards oral cancer screening among dentists.

METHODS

A 42-item survey was sent to 650 dental professionals affiliated with the University of Toronto. Data regarding training/practice characteristics, knowledge of oral cavity cancer, current screening practices, attitudes towards screening, and remuneration were collected.

RESULTS

Ninety-one dentists responded. Most obtained their dental degree from Canada (71.4%) and were practicing in large urban centers (87.9%). Most dentists correctly identified the oral tongue (87.8%) and floor of mouth (80%) as the two of most common sites of oral cavity cancer but only 56% correctly identified the most common presentation. 91% performed intra/extra oral examinations at every patient visit. Only 9.9% of dentists discussed the risk factors of oral cancer and 33% were not familiar with resources for smoking cessation and alcohol abuse. International medical graduates were more likely to discuss risk factor management than Canadian medical graduates (p < 0.01). Over 80% of dentists referred to a specialist when a suspected lesion was found. The greatest barrier for oral cancer screening was lack of time. Almost all dentists (98.8%) reported that their screening practices do not differ depending on the patient's insurance status and 63.8% reported compensation would not influence their decision to perform oral examinations.

CONCLUSION

Most dentists have a good knowledge of the presentation and risk factors associated with oral cavity cancer. Most dentists perform screening with every patient, with no influence from compensation and insurance status. Dentists are therefore an excellent first contact for oral cavity cancer screening for the general public and for high-risk populations.

Status and Determinants of Early Detection of Oral Premalignant and Malignant Lesions in India

It has been over four decades since the launch of the National Cancer Control Programme in India, yet the cancer screening rates for oral cancer remain unremarkable. Moreover, India is bracing a large burden of oral cancer with poor survival rates. An effective public health programme implementation relies on a multitude of factors related to cost-effective evidence-based interventions, the healthcare delivery system, public health human resource management, community behaviour, partnership with stakeholders, identifying opportunities and political commitment. In this context, we discuss the various challenges in the early detection of oral premalignant and malignant lesions and potential solutions.

Effectiveness of screening for oral cancer and oral potentially malignant disorders (OPMD): A systematic review

Oral cancer (OC) is a debilitating disease with a high mortality rate when diagnosed in advanced stage. Conversely, early-stage OC has a high survival rate, supporting a need for early detection programmes. A previous systematic review of clinical trials evaluating efficacy of screening for OC was inconclusive. This systematic review aimed to determine the impact of screening for oral lesions on reducing mortality and incidence of OC by looking at a broader spectrum of evidence. The search for randomized controlled trials and observational studies with a control group was conducted in PubMed, OVID, Cochrane, CINAHL and grey literature sources. Risk of bias for included studies was assessed with the tools developed by the Cochrane collaboration. Six out of two identified randomized trials and five observational studies had moderate to high risk of bias. Nevertheless, the predictions on impact of OC screening on incidence and mortality were similar across the majority of the studies. The meta-analysis concluded on a 26% decrease in OC mortality, and an 19% decrease in advanced OC cases as a result of OC screening in high-risk population. Three out of four studies did not identify an impact of screening on OC incidence. No positive impact of OC screening on incidence or mortality among general population was identified in the only available randomized trial. Consistency in the outcomes and the limitations of the few available studies suggest a need for real-life setting research to evaluate the overall effectiveness of screening for OC in high-risk population.

GLOBOCAN 2020 Report on Global Cancer Burden: Challenges and Opportunities for Surgical Oncologists

Cancer is emerging as a major public health challenge globally. Recently, IARC (International Association of Research on Cancer) published global cancer burden using GLOBOCAN 2020 estimates for 36 cancers in 185 countries of the world. As per the estimates of the World Health Organization (WHO) in 2019, cancer is the first or second leading cause of death in 112 of 183 countries. The major takeaways of the GLOBOCAN 2020 report relevant to the surgical oncology community include the rising global burden of cancer, global disparity in cancer incidence and mortality in different geographic regions, and the impact of the human development index (HDI) on cancer incidence and projected global cancer burden by 2040. In this article, we discuss the implications of the GLOBOCAN report on future global cancer control strategies and the role of surgical oncologists in the fight against cancer.

Salivary Metabolomics for Oral Cancer Detection: A Narrative Review

The development of low- or non-invasive screening tests for cancer is crucial for early detection. Saliva is an ideal biofluid containing informative components for monitoring oral and systemic diseases. Metabolomics has frequently been used to identify and quantify numerous metabolites in saliva samples, serving as novel biomarkers associated with various conditions, including cancers. This review summarizes the recent applications of salivary metabolomics in biomarker discovery in oral cancers. We discussed the prevalence, epidemiologic characteristics, and risk factors of oral cancers, as well as the currently available screening programs, in India and Japan. These data imply that the development of biomarkers by itself is inadequate in cancer detection. The use of current diagnostic methods and new technologies is necessary for efficient salivary metabolomics analysis. We also discuss the gap between biomarker discovery and nationwide screening for the early detection of oral cancer and its prevention.