To determine the possible contribution of endometriosis or chronic inflammation to the expression of FOXL2 by ovarian cancer stromal cells, we compared the presence of endometriosis and the number of CD138-positive plasma cells and CD163-positive macrophages between FOXL2-poor (score1, 2) and FOXL2-rich (score 3, 4) cases. Here, SDC1 is linked to endometriosis.