Ovarian cancer screening approach may be flawed

Annual ultrasound examination plus a blood tests to detect CA-125, a biologic tumor marker, may be adequate to detect early-stage Ovarian cancer in women at increased genetic risk, according to UK researchers.

The two cancer screening methods are "ineffective in detecting tumors at a sufficiently early stage to influence prognosis," Dr. Diane Sterling of Western General Hospital, Edinburgh and colleagues report in the Journal of Clinical Oncology.

The team came to this conclusion after examining data for 1,110 women with an increased risk of Ovarian cancer who were screened between 1991 and 2004. Of these subjects, 553 had a 4-percent to 10-percent lifetime Ovarian cancer risk and were deemed to be at moderate risk. The remaining 557 had a greater than 10-percent lifetime risk and were classified as high risk.

Overall, 12 invasive and one borderline ovarian malignancy developed in the group. Ten of these tumors were detected at screening.

Of the other three, one was found when the patient underwent surgical removal of the ovaries two months after normal screening results. The other two women developed symptoms within 12 months after normal screening results. Twenty-nine women underwent diagnostic surgery, but were not found to have Ovarian cancer.

Based on the findings, the researchers conclude that "the performance of ultrasound does not satisfy the World Health Organization screening standards."

In addition, this combination screening approach "has a particularly high false-positive rate in premenopausal women, leading to unnecessary surgical intervention," the researchers note.

However, in an accompanying editorial, Dr. Ian Jacobs of University College, London finds the study methodologically flawed. The researchers' results may be correct, he points out, "but it is not possible to reach this conclusion from the data they have presented."

In light of this and other studies in the medical literature, he stresses the "need for well-designed, rigorously conducted and properly funded...trials of Ovarian cancer screening."

SOURCE: Journal of Clinical Oncology, August 20, 2005.