Biomarkers Predict First-Line Treatment Response for Endometriosis
A PPM Brief
A new study1 found that biomarkers could predict whether women will respond to first-line treatment for endometriosis. While progestin-based therapies such as oral contraceptives are usually used for managing endometriosis-associated pain, response is typically unpredictable and varies among women. Hormonal therapy and surgery are two cornerstones of endometriosis management, both with high recurrence rates.
In a retrospective cohort study, researchers studied 52 subjects with endometriosis and found that progesterone receptor levels were an important predictor of progesterone responsiveness in endometriosis. Immunohistochemistry (IHC) was performed on sections of endometriotic lesions using a rabbit polyclonal IgG for detection of progesterone receptor (PR)-A/B. The Histo (H)-score was used for quantifying the PR status. Response to progestin-based therapies was determined from electronic medical record review. Subjects were categorized into three groups: high (H-score > 80, n = 7), medium (H-score 6-80, n = 28) and low (H-score ≤ 5, n = 17) PR status. The threshold of PR > 80 was associated with a 100% positive predictive value. The threshold of PR < 5 was associated with a 94% negative predictive value.
"Receptor status in endometriosis could be used in a similar way to how estrogen receptor and progesterone receptor status is used in breast cancer for personalizing treatment options," said lead study author Valerie A. Flores, MD, of the Department of Obstetrics, Gynecology and Reproductive Sciences at Yale School of Medicine in New Haven, CT. "Such an approach to endometriosis management could better determine which medication each individual patient responds to and minimize delays in providing the optimal medical therapy."
