Introduction/Background Leiomyomas are benign mesenchymal smooth muscle tumors found in 75% of hysterectomy specimens. There are several subtypes, among them plexiform leiomyoma. When they are microscopic findings are referred to as plexiform tumorlets. We report a case of plexiform tumorlet in a patient with history of invasive lobular carcinoma (ILC) and concomitant endometrioid carcinoma.

Methodology A 64 year-old patient with history of ILC three years ago was admitted to the gynaecology department due to recurrent vaginal bleeding. An endometrial curettage was performed. Histological diagnosis was endometrioid carcinoma grade I arising in a polyp. A hysterectomy and bilateral saplingo-oophorectomy was performed.

On microscopic examination residual endometrioid carcinoma was not present. Six uterine leiomyomas with a maximum diameter ranging from 1.2–4.3 cm were found. A small tumor measuring 3 mm was found in the uterine wall. It consisted of small nests, islands, cords and tubules of epithelioid cells surrounded by loose stroma. Mitotic figures, pleomorphism or necrosis were absent. The differential diagnosis included plexiform tumorlet, uterine tumor resembling ovarian sex cord tumor and metastatic ILC.

Immunohistochemical study was positive for SMA, Desmin, CD56 and negative for AE1/AE3, EMA, Inhibin, WT1 and CD99.

Results The diagnosis of leiomyomatous uterus consisting of six leiomyomas and a plexiform tumorlet was made. The patient is alive without any evidence of recurrence or metastasis fifteen months after surgery.

Conclusion Plexiform tumorlet is a very rare variant of epithelioid leiomyomas. It is usually discovered incidentally, showing a benign clinical course.

Disclosure Nothing to disclose.