David Huntsman
UBC cancer researchers have led an international study to improve diagnosis of a rare sub-type of ovarian cancer that has been notoriously difficult to accurately identify.
The team created an algorithm to diagnose and predict the clinical course of adult-type granulosa cell tumours (AGCTs) of the ovary, which make up 3 per cent to 5 per cent of ovarian cancers.
“Effective cancer treatments rely on having an accurate diagnosis in the first place, and the results of our research underline the importance of this,” says lead investigator David Huntsman, the Dr. Chew Wei Memorial Professor of Gynecologic Oncology at UBC and scientific leader of OVCARE, British Columbia’s multidisciplinary ovarian cancer research program.
Outcomes for AGCTs seemed to be all over the place. While standard diagnosis is based on how tumour tissue appears under a microscope, recent research found that many AGCTs had a mutation in the FOXL2 gene. The Vancouver-based team wanted to see if FOXL2 could be used as a robust marker for the disease.
As described in their study, published in June in the Journal of the National Cancer Institute, the team used historical cases of tumours categorized as AGCT of the ovary from three major European centres.
“While the cases we examined had the most accurate diagnosis possible at the time, our team found that about 20 per cent were actually of different sub-types of ovarian cancer,” says Dr. Huntsman, a Professor in the Department of Pathology and Laboratory Medicine and the Department of Obstetrics and Gynaecology. “By assessing only the true cases of AGCT, a clearer picture emerged: the survival rates were very high for those with true AGCT and more than 95 per cent of those cases had a mutation in the FOXL2 gene, making it a disease-defining marker to use in diagnosis.”
The majority of deaths attributed to AGCT in the study were actually caused by aggressive forms of other types of ovarian cancer, says Dr. Huntsman, head of Terry Fox Research Institute’s New Frontiers Program Project Grant in the Genomics of Forme Fruste Tumours. The project studies rare tumours; historically, research on these kinds of tumours has yielded knowledge on our understanding of common cancers.
Dr. Huntsman says their research produced other important information for patients and doctors.
“For those with true AGCT we realize that the prognosis is actually very good, removing a great deal of stress for patients and their families,” he says. “For those who might have previously been diagnosed with AGCT, but who actually have a different form of ovarian cancer, this method will prompt clinicians to follow-up with further tests for an accurate diagnosis and ensure a more appropriate treatment plan. We wrote the paper with future patients in mind, hoping it will be used by health care providers to help explain the implications of this diagnosis and in many cases mitigate the fear that comes with a cancer diagnosis.”