Pseudolipomatosis affects specimens from endometrial biopsies.

Pseudolipomatosis refers to optically clear vacuoles that artifactually contaminate specimens, and it most commonly affects the gastrointestinal tract. Pseudolipomatosis closely resembles adult white fat and is of group "A" or "B" when vacuoles have mild or marked variation in size, respectively. Pseudolipomatosis has yet to be reported to occur in the endometrium. Pseudolipomatosis in the endometrium might be easily mistaken for extrauterine adipocytes and misdiagnosed as perforation. We retrospectively reviewed 50 consecutive specimens from endometrial biopsies to determine the prevalence of endometrial pseudolipomatosis and whether pseudolipomatosis was related to perforation. All 50 specimens contained pseudolipomatosis of group "B," and lacked extrauterine tissue. To our knowledge, all patients lacked clinical evidence of perforation at follow-up. Pseudolipomatosis commonly affects specimens from endometrial biopsies and is likely unrelated to perforation. Awareness of pseudolipomatosis is necessary to avoid misdiagnosing uterine perforation.