New test for ovarian cancer met with caution

GPs may be inundated with patient queries about a new early stage diagnostic test for ovarian cancer, following its widely publicised launch last week.

However, experts are warning that the test needs more research before it can be recommended for routine use.

Details of the OvPlex serum test were announced last week and it is already available to GPs in Melbourne.

The test, which costs about $200, is not covered by Medicare and is not approved by the TGA. It measures a combination of five biomarkers, including CA-125.

Dr Helen Zorbas, director of the National Breast and Ovarian Cancer Centre, said given the high mortality from ovarian cancer, new research into ways of increasing early detection were welcome.

“There are currently a number of tests in development worldwide to detect ovarian cancer in its early stages through the presence of protein biomarkers in the blood, [and] OvPlex is one of these tests being marketed for use in the diagnostic setting,” she said.

While these tests may have a role in the future in improving the detection of ovarian cancer, she said “further validation in large clinical trials is required before they could be recommended for routine use”.

The test claims to have a sensitivity of 94.1% and a specificity of 91.3 per cent.

Professor Greg Rice, chairman of the test’s co-developer, HealthLinx Ltd, emphasised that while the test may be superior to using CA-125 alone, it does not have the specificity required for use in screening the asymptomatic population.

“For it to be a community-based screening test, it would need to have a specificity of 99.6%,” he said.

HealthLinx, in collaboration with ARL Pathology, is promoting the test for use as a more accurate replacement of CA-125.

“The multi-marker panel... actually picks up cases of ovarian cancer where CA-125 alone does not,” Professor Rice said.

An unpublished, phase II retrospective case-control study of 362 women, including 150 newly diagnosed cases of ovarian cancer prior to treatment, had validated the five-biomarker model for predicting disease, he said.

The test will be available to GPs in Melbourne initially, and while the sole laboratory doing the assay, ARL Pathology, will accept tests from interstate, this will be at an increased cost.

A TGA spokeswoman said more information was being sought from HealthLinx about its test.

The test would not necessarily require registration, as some diagnostic kits were exempt, “depending on what they contain and what they purport to do”, she said.