Ultrasound Expertise Important in the Diagnosis of Ovarian Cancer
Improving the quality of diagnostic ultrasound scans could significantly reduce unnecessary surgeries in women with suspected ovarian cancer who, in fact, have benign disease, according to a study by British researchers.
Lancet Oncology, published online January 21, 2008, in print February 2008 (see the journal abstract).
(Lancet Oncol. 2008 Feb;9(2):124-31)
An ultrasound scan uses sound waves to create an image of the internal organs of the body. Sonographers, who may or may not be doctors, are specifically trained in ultrasound scanning.
Women who have symptoms that suggest an ovarian tumor usually undergo a diagnostic ultrasound scan. Because of the complexity of the organs in this area, gynecological ultrasonography can be difficult to perform and interpret. Studies have shown that experts in gynecological ultrasonography can accurately distinguish between benign and malignant tumors 95 percent of the time. In the absence of a definitive ultrasound result, many women are referred for exploratory surgery to find out if cancer is present.
In this study, which was conducted in the United Kingdom, 150 women with suspected ovarian tumors were assigned at random to receive either “expert” or “routine” ultrasonography. The expert scans were performed by gynecologists who specialized in gynecological ultrasonography, had more than 10 years’ experience, were active in research, and were involved in training less-experienced practitioners. The routine scans were performed by nonphysician ultrasonographers who were trained in gynecological ultrasonography but were not specialists in this field.
Researchers kept track of how many other procedures, including follow-up diagnostic tests and exploratory surgery, the women in each group had, as well as how many days they spent in the hospital. The average follow-up period was about 14 months. The study’s principal investigator was Joseph Yazbek, M.D., of King’s College Hospital in London, United Kingdom.
Thirty-seven percent of the women who had routine scans went on to have exploratory surgery, compared with 22 percent of those who had expert scans. The ultrasound scan resulted in a definitive diagnosis in 99 percent of women in the expert group but in just 38 percent of those in the routine group. Eighteen of the 150 patients enrolled in the study (12 percent) were found to have ovarian cancer.
More women who had expert scans received minimally invasive procedures (27 percent, compared with just 6 percent of women who had routine scans). In addition, the median hospital stay was a day shorter (five days instead of six) for women who had expert scans.
Despite significant differences in medical practice between the United Kingdom and the United States, this study’s findings are important and relevant for women with suspected ovarian cancer in this country, says Edward L. Trimble, M.D., M.P.H., of the National Cancer Institute’s Cancer Therapy Evaluation Program.
In the U.S., many women have an ultrasound scan to diagnose a suspected ovarian tumor in their gynecologist’s office, explains Trimble. Like the ultrasonographers who performed the routine scans in this study, most U.S. gynecologists are not experts in gynecological ultrasonography. As a result, many women in the U.S. are referred for exploratory surgery because the doctor cannot determine from the ultrasound scan whether a tumor is benign or malignant.
Dr. Trimble recommends that women seek a second opinion on their ultrasound scan before agreeing to have surgery. “The number of surgeries to obtain a definitive diagnosis could be reduced if more women got a second opinion on their scan from a senior radiologist with a special interest in gynecological cancer imaging,” he says.