Researchers have detected an alarming rise in tongue cancers among young Australian women who have none of the known risk factors for the potentially deadly condition.
Tongue cancers have increased 385 per cent over 32 years in women aged from their teens to 44, found an analysis of 11,682 patients with the disease in Australia and Singapore.
Janine Chung survived tongue cancer. Credit:Janie Barrett
These cancers are traditionally found in older men with a history of heavy tobacco smoking and drinking.
But the rate of tongue cancer was rising by roughly 4.5 per cent every year in young women, very few of whom smoke, or they have not been exposed to alcohol and smoking long enough for the cancers to have developed from these risk factors.
Nor were their tongue cancers - on the side of the tongue - linked to the human papillomavirus (HPV).
The study’s co-author and head and neck surgeon at Chris O'Brien Lifehouse Associate Professor Carsten Palme said it was a disturbing and perplexing trend.
“It is a small group of women but also a significant group who often fall through the cracks because they don’t promptly recognise the disease,” Associate Professor Palme said.
“We need to work out what’s causing it. If there’s a common link or defect then maybe we can screen for it [and develop a targeted treatment]."
Janine Chung was 18 when she was diagnosed with Stage 3 tongue cancer in 2015. She had put up with an ulcer on the side of her tongue for months as she worked through her HSC.
When she did see her doctor and had a biopsy she was shocked to learn it was cancerous, "but in the back of my mind I knew for something to have been there for so long it wouldn’t be minor”, Ms Chung said.
She had "a 20-cent coin-sized chunk" of her tongue cut out and lymph nodes removed from her neck.
“It taught me that just because you’re young, don’t be naive. If you have any health concerns get it checked out straight away,” the 23-year-old said.
Tongue cancers are relatively uncommon in Australia. By the end of 2020, 5168 people are expected to be diagnosed with head and neck cancer, of which tongue cancer accounts for roughly one-third of cases.
If the cancer is detected early and expertly treated at a specialised head and neck cancer centre, the five-year survival rate is above 70 per cent, but survival drops below 50 per cent if the cancer is in its more advanced stages.
“The numbers aren’t too high now but they could become significantly higher over the next decade,” Professor Palme said.
Professor Dorothy Keefe, the chief executive of Cancer Australia, said the findings suggested that yet again we think we have a firm grasp of the risk factors for cancers “and then they change”.
“It happened with lung cancer where for decades most were caused by smoking, but now we’re seeing an increasing number in non-smoking women,” Professor Keefe said,
“I think this is a similar story. There is another risk factor coming into play that we don’t know about yet. In lung cancer it was genetic changes that caused it,” she said.
Professor Palme, in collaboration with a research team from Chris O’Brien Lifehouse the University of Sydney, Royal Prince Alfred Hospital and the Garvan Institute, has sequenced the whole genomes of 20 young female tongue cancer patients, and so far 70 per cent have mutations called ‘whole-genome duplication’, which occurs when cells receive four copies of every chromosome instead of two.
The researchers have also found an association with a mutation in the TP53 gene (a tumour suppressor gene). Mutations in this gene cause uncontrolled cellular growth.
Tongue cancer with whole-genome duplication was also associated with shorter survival.
More research is needed to prove any genetic link and, hopefully, find a targeted treatment.
In the meantime Professor Palme urged anyone with persistent ulcers in their mouths to seek medical attention and if necessary get treatment from a highly specialised head and neck surgeon.
Genetic cause or not, Professor Keefe warned smoking and alcohol were still major risk factors for many cancers, and encourage people to minimise both.