PAX2, PTEN, and β-catenin immunostains were performed on endometriosis-associated endometrioid ovarian lesions from a total of 85 patients, including 32 usual-type (nonatypical) endometriosis/endometriomas, n=5 EA, n=19 EBT, and n=29 endometrioid adenocarcinomas (n=16 FIGO Grade 1, n=10 Grade 2, and n=3 Grade 3). The gene discussed is PAX2; the disease is endometriosis.