Tackling Ovarian Cancer, "One Histotype At a Time"
In 2008, the OVCARE team announced an important discovery showing that ovarian cancer is not a single disease but is made up of a spectrum of distinct diseases. “Until now,” says OVCARE team leader, Dr. David Huntsman, “ovarian cancer has been treated as a single disease in both the cancer clinic and the research lab.” The OVCARE team has shown that progress depends on both clinically managing and researching these histotypes as distinct diseases.
The discovery, published in the journal PLoS (Public Library of Science) Medicine,will lead to new avenues for early detection and more effective customized treatments for women with ovarian cancer.
Ovarian cancer has always been a difficult disease to diagnose and treat. The symptoms in early stages are often vague, leading to late stage diagnosis and poor outcomes. Treatment has also remained homogeneous, using a combination of platinum and taxane based chemotherapy, even though physicians and researchers have suspected different subtypes exist and respond to treatment in different ways. Many scientists have been focusing their efforts on developing biomarkers for early detection and prognostication as a means to better diagnose the disease and increase survival, but this study shows that approach has been flawed because while biomarkers of different ovarian cancer subtypes vary, previous studies lumped subtypes together as one disease. The biomarker identification of separate ovarian cancer subtypes means a distinct path is now available for researchers to follow.
“We have been able to identify and attach specific biomarkers for five different subtypes of ovarian cancer,” said Dr. David Huntsman, lead author and genetic pathologist at the BC Cancer Agency and Vancouver General Hospital and associate professor in UBC’s Department of Pathology and Laboratory Medicine. “The biomarkers are the same for each subset from early diagnosis through late stage, meaning we can develop screening tools that can identify and predict the type of ovarian cancer and outcome, and from this point we can develop customized treatments. This is important because some subtypes are more deadly than others, and they cannot all be treated the same way.”
To expedite the uptake of this information, the researchers have created a comprehensive image bank to allow the international ovarian cancer research community to be able to see all of the experimental data and reproduce the analysis. “We believe we have set a new standard for how tissue-based biomarker studies should be performed,” says Dr. Huntsman.
The OVCARE team was able to make this discovery because of the centralized treatment and record keeping at the BC Cancer Agency and the Genetic Pathology Evaluation Centre (GPEC) located at Vancouver General Hospital.
“We have some unique features in British Columbia that allow us to break new ground in biomarker studies,” said Dr. Blake Gilks, Director of Anatomic Pathology at Vancouver General Hospital and professor in UBC’s Department of Pathology and Laboratory Medicine. “The centralization of treatment and excellent record keeping of the BC Cancer Agency provide a large data pool to draw from that other areas don’t have. The GPEC lab is solely dedicated to improving the management of cancer patients through the validation of prognostic and predictive cancer biomarkers, and finally, the multidisciplinary nature of the OVCARE team allows us to quickly bring observations from the patient’s bed to the lab and back again.”
Ovarian cancer affects about one in 70 Canadian women. Approximately 2500 new cases are diagnosed each year and the five-year survival rate is only 30 percent.
“This discovery is exciting to us because the way we have been treating ovarian cancer for the last several decades can be equated to trench warfare,” says Dr. Dianne Miller, gynecologic oncologist, BC Cancer Agency and Vancouver General Hospital. “We have only had one approach and the line never moved. We can now develop new strategies that will prove more effective against this deadly disease.”