Ovarian cancer test promising

A step-wise approach accurately spots early stage ovarian cancer in older women at average risk for the disease, new research suggests.

This cancer is known as a silent killer because it is often diagnosed too late to be successfully treated. Scientists have long sought a reliable method of early detection. The "Risk of Ovarian Cancer Algorithm" (ROCA), which uses a mathematical model, is geared specifically to postmenopausal women at average risk for the disease.

"This ROCA algorithm represents yet another example of personalised medicine. This is personalised towards a screening strategy for a vicious cancer," explained Dr Douglas W. Blayney, ASCO president, professor of internal medicine at the University of Michigan Medical School and medical director of the Comprehensive Cancer Center at the University of Michigan.

However, experts are awaiting the results of a much larger trial, due out in 2015, before recommending this as routine procedure.

"This is not practice-changing at this time," said study lead author Dr Karen Lu, professor of gynecologic oncology at the University of Texas M.D. Anderson Cancer Centre.

No effective screenng method

Ovarian cancer is the most lethal gynaecologic cancer and the fourth leading cause of death in cancer in women," Lu said. "Over 75% of cases present with advanced-stage disease, when the cure rate is less than 30%. There is no effective screening method at the current time."

Measuring levels of a blood protein called CA-125 can help detect ovarian cancer, but the marker is far less than perfect.

This study involved more than 3 200 postmenopausal women, aged 50 to 74, who had not had ovarian cancer themselves and who had no significant family history of breast or ovarian cancer.

The women started off getting a CA-125 blood test every year. If the test indicated low risk, the women could wait another year before their next test. If levels were elevated, putting them in an intermediate-risk category, however, the women were scheduled for a follow-up test in three months.

If that test was also high, the women were considered high risk and underwent transvaginal sonography (TVS) or ultrasound, and were referred to a gynaecologic oncologist, who decided whether or not surgery was needed.

Over the nine years of the trial, 6.8% of the volunteers were bumped up to the three-month CA-125 test group, while only 1% were referred to TVS and a cancer specialist.

What the study found

In total, eight of the more than 3 ,200 women underwent the recommended surgery. Three of those had invasive early-stage cancer (the three had undergone three years of annual CA-125 testing before moving to the next group), two had "borderline" ovarian tumors and the remaining three had benign ovarian tumours.

The specificity of the ROCA method was 99.7%, meaning there were virtually no false-positives, the team noted.

No women with invasive ovarian cancer were missed by the test, Lu said.

If results of the larger ROCA trial, currently underway in Britain, are encouraging, ROCA may be coming to a doctor's office in the not too distant future, "part of the routine health exam for postmenopausal women," Blayney said. - (HealthDay News, May 2010)