Mesonephric carcinoma is a malignant gynecologic tumor most commonly arising in the cervix and is presumed to be derived from normal or hyperplastic mesonephric remnants [
1]. Recently McFarland et al. [
2] reported a series of 5 ovarian and 7 uterine endometrial neoplasms that were referred to as “mesonephric-like adenocarcinomas (MLAs)”; these tumors exhibited the classical histologic features of mesonephric carcinomas. MLAs are rare, representing approximately 1% of endometrial carcinomas, but appear to be aggressive in nature [
3,
4]. Histologically, MLAs are characterized by a variety of morphologies including tubular, ductal, papillary, retiform, and solid. These histologic patterns can easily be mistaken for endometrioid carcinoma, clear cell carcinoma, serous carcinoma, carcinosarcoma, and a variety of other neoplasms [
4,
5]. They also have a unique immunohistochemical profiles; they are usually positive for thyroid transcription factor 1 (TTF-1), GATA binding protein-3 (GATA-3), and CD10, and are negative for estrogen receptor (ER) and progesterone receptor (PgR) [
2,
6]. MLAs are often confined to the endometrium without deep myometrial involvement, where mesonephric remnants theoretically exist [
2]. MLAs harbor recurrent mutations in
KRAS and
PIK3CA but lack
PTEN mutations, demonstrating biological overlap with both mesonephric and endometrioid carcinomas [
7]. The pathogenesis of MLAs is unknown, and it remains debated whether they represent mesonephric (Wolffian) carcinomas arising in the endometrium/ovary or endometrioid (Müllerian) carcinomas that closely mimic mesonephric carcinomas. Herein, we report for the first time a case of a patient diagnosed with an endometrial MLA coexisting with a low-grade endometrioid carcinoma.