Over the last decade researchers have become concerned about a possible link between a benign gynecologic lesion called endosalpingiosis (ES) and ovarian cancer. However, using a diagnostic method typically reserved for specimens suspicious for cancer, a team of researchers led by a Baylor College of Medicine physician found the prevalence of ES and other gynecological lesions was substantially higher than previously reported, even among women without cancer. This higher rate of occurrence led the researchers to believe that ES is not a direct cause of cancer as previously suspected. Their findings are published in the journal PLOS ONE.
“Recently, researchers started to wonder if ES could be a precursor to ovarian cancer,” said Dr. Jan Sunde, associate professor and division director of gynecologic oncology at the Dan L Duncan Comprehensive Cancer Center at Baylor. “An association of cancer with ES would make ES a concerning finding. But pathologists weren’t reporting benign ES lesions in all surgical cases, and the actual prevalence of ES was unknown.”
Sunde led this research during his time at the Madigan Army Medical Center in Tacoma, Washington. He worked with pathologists there to use a more stringent analysis to determine the actual prevalence of ES in all gynecologic samples, those with cancer and without, at their institution. After implementing the new protocol, the reported prevalence of ES increased from 2.54 percent to 22.15 percent in all specimens over a one-year period. When sorting the data by age group, the researchers found an ES prevalence of 37 percent in women age 31-50 and 66 percent in post-menopausal women.
“This is a way more common finding than what people suspected,” Sunde said. “If ES occurs so frequently, then it likely is not the first step in cancer development, and it’s much less concerning.”
Women with ovarian cancer do have ES at a higher rate, but Sunde said this could be due to sampling bias. Women with cancer undergo more thorough pathology testing, and studies of ES and cancer do not include a control group of ES patients with no cancer. Sunde said further study is needed to determine the true association between ES and cancer.
Next, Sunde and his team at Baylor will focus on what conditions allow ES to develop and whether any of those may also be linked to cancer.
“We know there are some benign ES lesions that have the same genetic mutations found in malignant lesions in patients who have an ovarian borderline tumor,” Sunde said. “We hope to find a way to evaluate ES lesions that would tell us if a patient is at risk for developing either borderline or high grade ovarian cancer. If we figure that out, we can evaluate methods of preventing this deadly cancer.”
