Oral Cancer Screening

People can screen themselves for asymptomatic oral cancers by regularly examining their own mouth in a mirror and reporting any changes to their dentist or doctor. These screenings can be organized as part of a dental or general health screening program, or as opportunistic.


The detection rates for OPMDs increased with subsequent screening, except in the case of leukoplakia/erythroleukoplakia and verrucous hyperplasia. The PPVs for these OPMDs also increased with age.


In the laboratory, a pathologist looks at your cells under a microscope to see if they are normal. This is called cytology.

Cytology is a non-invasive screening tool for oral epithelial dysplasia and cancer. However, it has a high false negative rate, and to date few studies have assessed the reasons for this.

A specialized mouthwash or a brush is used to scrape off some of the cells in the area of your mouth being tested, and the samples are then sent to a lab for analysis. There are two types of cytology used for oral lesions, conventional (CC) and liquid-based (LBC). LBC has been shown to have better sensitivity, specificity and positive predictive value than CC.

Before a cytology sample is taken, your healthcare provider will rinse the area and then shine a special light in your mouth to make healthy tissues look dark and abnormal tissues look white. This is called fluorescence cytology, and it is a way to help the pathologist identify atypical cells more easily. During this test, the pathologist also examines your lips, cheeks and tongue to check for red or white patches of tissue, thickened areas and rough or raised surfaces. They may use a finger to feel (palpate) for lumps or swelling in the area of your mouth being tested.

Brush Biopsy

Brush biopsy is an easy and non-invasive technique to evaluate an oral lesion. The specimen is collected with a cytology brush that samples the entire thickness of the epithelium in a non-irritating fashion and then disaggregated to identify potential abnormal cells. The brush is then examined with the specialized microscope to determine whether there are any cellular changes present.

A recent study analyzed brush biopsies that were matched with scalpel biopsies from patients who underwent an evaluation for suspicious lesions of the oral mucosa. The study demonstrated that the computer analysis of a brush biopsy is a sensitive and specific tool to distinguish squamous cell carcinoma from other neoplasias. The findings of this study demonstrate that a brush biopsy is an important addition to the diagnostic toolbox for oral cancer screening and could decrease the number of unnecessary invasive biopsies in this population.

The PDQ cancer information summaries are prepared by the National Cancer Institute (NCI), part of the National Institutes of Health, and are reviewed regularly to reflect new medical evidence. These summaries are for general education only and do not replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.

Although several studies have shown that brush biopsy is a reliable method to differentiate squamous cell carcinoma from other oral mucosal lesions, it cannot diagnose all neoplasias. Therefore, if a patient is clinically suspicious of a lesion and the brush biopsy report is negative, it is important to follow up with a scalpel biopsy.

Mucosal Staining

Conventional oral examinations using visual inspection and palpation can miss subtle lesions. Even when a suspicious lesion is identified, diagnosis often requires biopsy and histopathology. Early detection and diagnosis significantly improves survival rates. While a biopsy and histopathology are the only way to diagnose mouth cancer, several adjunctive tools help clinicians identify and characterise oral mucosal abnormalities.

One of these is a staining technique with Lugol’s iodine, which makes the appearance of a malignant lesion more visible. The iodine reacts with the oxygen in the air to produce a blue color that contrasts with normal appearing mucosa. The coloration also helps to delineate the extent of a dysplastic or malignant lesion (Gandolfo et al., 2006).

Another tool to assist with the identification of a suspicious oral lesion is digital color analysis. The GOCCLES device (Pierrel Pharma Srl, Italy) is an easy-to-use, portable system that allows clinicians to record the colour and texture of the suspicious area. This is achieved by filtering the light from any dental curing light to highlight the autofluorescence of the oral mucosa.

The USPSTF found insufficient evidence about the balance of benefits and harms to recommend TB staining as a routine procedure for screening for oral premalignant and malignant lesions in asymptomatic adults. However, there is a growing body of evidence that combining TB staining with brush biopsy increases the accuracy of oral cancer detection and reduces the number of patients needing unnecessary biopsies.

Chemiluminescent Light

Many adjunctive optical techniques have emerged claiming to improve detection and distinction of oral mucosal lesions. These use chemiluminescence and tissue autofluorescence to highlight abnormalities. The principle is that cells and tissues contain molecules called fluorophores that emit light when illuminated with specific wavelengths of light. When a blue-white diffuse light source (such as the Microlux Transilluminator 2) is used to illuminate mucosal areas, the light reflected from normal epithelium is greenish and that of malignant and pre-malignant lesions is white.

Commercially available chemiluminescent devices such as the ViziLite and toluidine blue have been adapted from gynecological and cervical cancer screening for use in the mouth. The technique is referred to as lumenoscopy and involves inspection of the cervix following rinsing with acetic acid, to enhance cell surface transparency allowing chemiluminescence of cellular proteins to be visualised.

The application of acetic acid also increases the nucleus to cytoplasmic ratio in cellular structures of the oral epithelium, thereby increasing their reflectance and making them appear white under blue-white illumination. It is thought that this increased luminosity distinguishes them from benign squamous mucosa which reflects red (see Figure 1).

However, the studies to date have shown variable results and some reported no improvement in lesion identification compared to histopathology. Further, a number of these studies were conducted using per-patient analysis which may influence the results. Some investigators have combined chemiluminescence with toluidine blue staining and report better sensitivity and specificity. Nevertheless, the technique is promising and may reduce the need for noninformative biopsies.