Study confirms dentists’ key role in oral cancer detection
TORONTO, Canada: A new study has shown that dentists are playing an important role in detecting oral cancer. After examining data gathered over an 11-year period in a provincial study—the first of its kind—researchers found that dentists in the Canadian province of Ontario are detecting more cases of oral cancer and precancer than ever before. Early detection of cancer increases the chances of successful treatment and is therefore key to saving patients’ lives.
In the study, researchers at the University of Toronto looked at 63,483 biopsies submitted to the Faculty of Dentistry’s Toronto Oral Pathology Service (TOPS) between 2005 and 2015. “We wanted to look at the scope of oral biopsies performed by dentists, what they’re seeing in practice,” said the lead author of the study Dr. Marco Magalhaes, an assistant professor in the Faculty of Dentistry and an oral pathologist at TOPS. The biopsy data from TOPS was then compared with numbers collected by the Ontario Cancer Registry, Cancer Care Ontario, which tracks all reported cases of cancer in the province.
The data showed a steep rise in the overall numbers of carcinomas and dysplasia detected by dentists. Overall, 828 cases of oral cancer were diagnosed by TOPS between 2005 and 2015, along with 2,679 premalignant lesions. However, the percentage of oral cancer detection by oral health professionals rose significantly over time. In 2005, only 56 cases of oral cancer and 99 cases of oral epithelial dysplasia were detected through biopsy. By 2015, the number of cancers had nearly doubled, rising to 103 cases of oral cancer. Dysplasia cases more than tripled from 2005, rising to 374 cases. “These numbers are important because the number of diagnosed cases outpaced both the rise in population in Ontario and the increased number of dentists licensed in Ontario,” said Magalhaes.
The number of cases detected at TOPS rose by 180 percent, a significantly higher increase than the 30 percent overall increase of oral cancers recorded in the province over that same period. Cancer Care Ontario identified a total of 9,045 cases of oral cancer between 2005 and 2015.
According to Magalhaes, comprehensive training and continuing education programs for oral health professionals may explain why dentists in Ontario play such an important role in early detection of cancer. While advanced oral cancers are fairly easy to detect, premalignant lesions and early cancer, which are crucial to survival rates, can be harder to spot without specialized training, he explained. According to the Canadian Cancer Society, patients treated in the early stages of oral cancer have the highest survival rates, between 75 and 93 percent over five years depending on the tumor site. The number drops to approximately 38–63 percent over five years when the cancer is detected at a locally advanced or regional stage.
The study, titled “Increase in detection of oral cancer and precursor lesions by dentists: Evidence from an oral and maxillofacial pathology service,” was published online on April 25, 2019, in the Journal of the American Dental Association ahead of inclusion in an issue.