True incidence of uterine adenomatoid tumors.

Uterine adenomatoid tumors (UATs) are benign tumors of the uterine serosa and myometrium that originate from the mesothelium and forming gland-like structures. This study was conducted in order to determine the true incidence of UATs, which are usually an incidental finding during uterine surgery performed for other causes. UATs may resemble pre-existing vessels and lymphatic ducts, as well as metastatic adenocarcinomas. A total of 199 consecutive surgical operations (134 hysterectomies and 65 uterus-preserving tumor excisions) were performed by a single team of gynecologists and examined by a single attending pathologist, who performed a thorough macro- and microscopic examination of all the specimens. UATs were identified in nine (5%) out of the 199 cases [six (5%) out of the 134 hysterectomies and three (5%) out of the 65 uterus-preserving tumor excisions]. Therefore, the true incidence of UATs may be significantly higher than 1%, which is the incidence reported in the presently available literature.