Mouth mapping to find oral cancer
A saliva test, a cutting-edge probe and new software promise to detect oral cancer more quickly and effectively.
According to the World Health Organization, more than 370,000 cases of oral cancer are diagnosed each year. In Australia, around 900 oral cancer cases are diagnosed each year that affect the tongue, lips, cheeks, gums, back of the throat or the soft palate of the mouth.
It can be an aggressive cancer with a 50 percent survival rate over five years.
As with many cancers, early diagnosis is key – especially the early diagnosis and management of oral potentially malignant disorders (OPMDs) before they transform into oral squamous cell carcinoma.
Dr Tami Yap is an oral medicine specialist and clinician-researcher at the Melbourne Dental School and a fellow of the Royal Australasian College of Dental Surgeons. She spent six years in general practice before specialising in oral medicine and has a particular interest in oral pre-cancer.
Dr Tami Yap.
“Oral cancer is often lumped with other fields of dentistry and I don’t feel there’s the same level of advocacy as there is for other cancers. But it is a cancer that has great impact. People may lose a large portion of their jaw or half their tongue. It changes their speech, how they eat and swallow. Part of their face may always feel numb and it can change their smile and those impacts can last forever,” says Dr Yap.
“Surgery to remove the tumour is the main treatment and 1cm around the tumour has to be removed to prevent cancer coming back. If you remove that from your leg you wouldn’t notice it as much, but it is much more noticeable in your face.”
Preventing a disorder in the mouth from progressing to cancer has been the focus of Dr Yap’s PhD research. She examined molecules in saliva that could help predict if a patient had oral cancer – identifying oral cancer in its earliest stages and before symptoms were visible.
The test was a simple oral swirl that was washed around the mouth and expelled into a tube for analysis. The test predicted that oral cancer was present with a high level of accuracy and it has also been studied for throat cancer risk.
Progressing oral cancer prevention research further, Dr Yap and the Melbourne Dental School partnered with Optiscan Imaging Ltd as part of a BioMedTech Horizons Program that uses Optiscan’s non-invasive confocal endomicroscopy system to enhance oral cancer screening. The leading imaging technology has been successfully miniaturised into a 4.7mm diameter probe that allows digital biopsy, reducing the need for surgical biopsy.
“We have worked with Optiscan to optimise the use of the handheld probe of their InVivage device to make it user-friendly. It’s similar to holding a pencil,” says Dr Yap.
Imagery taken from the MouthMap software, published in the Frontiers of Oncology journal.
“We also worked with MoleMap, who have expertise in skin cancer screening, to create a first version of a software called MouthMap that houses and annotates life-size and microscopic digital images of the mouth captured by the probe.”
Artificial Intelligence is also being harnessed to analyse the thousands of images captured by the probe to predict oral cancer risk, or to identify pre-cancerous changes that require treatment.
Dr Yap’s next piece of research will make the MouthMap software web-based and used to run a community level program in Bendigo. Patients will be able to have their mouth screened using the probe, digital images that will be analysed and reported on by oral dermatologists. The report will be sent to the patient’s local GP and dentist with any recommendations depending on what the images present.
“I’d like to see the tools we have been working on used in clinical practice – we need to show the community that these tools are helpful in detecting oral pre-cancer. I see that MouthMap could be used at the first level and then escalated to the saliva molecule test and digital biopsy if needed,” says Dr Yap.
“I’d like to see Melbourne Dental School become a centre of research excellence in this field. We have clinicians across the treatment pathways for oral cancer, we have experienced scientists and we have spaces where we can test new therapies and personalised medicine to make a difference.”