Indian Journal of Pathology and Microbiology

: 2010  |  Volume : 53  |  Issue : 4  |  Page : 793--795

Giant uterus-like mass of the uterus

El Harroudi Tijani1, Taleb Meryem2, Gamra A Lamya2, Jalil Abdelouahed3,  
1 Faculty of Medicine, Oujda; Department of Surgery, National Institute of Oncology, Rabat, Morocco
2 Department of Pathology, National Institute of Oncology, Rabat, Morocco
3 Department of Surgery, National Institute of Oncology, Rabat, Morocco

Correspondence Address:
El Harroudi Tijani
BP: 502, Oujda principale, Oujda


Uterus-like masses, such as cavities lined by endometrium-type mucosa surrounded by bundles of smooth muscle cells, may strikingly resemble the uterus. In this report, we describe a case of a uterus-like mass of the uterus in a 35-year-old woman.

How to cite this article:
Tijani E, Meryem T, Lamya GA, Abdelouahed J. Giant uterus-like mass of the uterus.Indian J Pathol Microbiol 2010;53:793-795

How to cite this URL:
Tijani E, Meryem T, Lamya GA, Abdelouahed J. Giant uterus-like mass of the uterus. Indian J Pathol Microbiol [serial online] 2010 [cited 2021 Jan 15 ];53:793-795
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Full Text


Uterus-like mass of the ovary is a unique disease entity proposed by Cozzutto in 1981. [1] It represents a cavity lined by endometrium-type mucosa surrounded by bundles of smooth muscle cells and may show a striking macroscopic and microscopic resemblance to the uterus. [2] We report a case of a giant uterus-like mass of the uterus and review the relevant literature.

 Case Report

A 35-year-old nulliparous woman was admitted to hospital with intense pain in the left iliac fossa and pelvis. She had intermittent bouts of similar but less severe pain and continuous vaginal bleeding and dysuria for the previous 8 months. Physical examination revealed an abdomino-pelvic mass with a large cystic component reaching until the epigastric area. An ultrasound scan demonstrated a cystic mass arising probably from the left ovary. There was no ascites. Her serum CA125 level was elevated (161 U/mL).

At laparotomy, a 16 × 21 cm sized mass was located in posterior fundus of the uterus and posterior face of the bladder, attached to these organs [Figure 1]a. The mass was surgically excised, requiring marsupialization for complete excision [Figure 1]b. Both the ovaries and cornua of the uterus were entirely normal.{Figure 1}

The mass was grossly well circumscribed and had variably sized cystic spaces surrounded by a thick layer of muscle. The cystic portion looked like endometriosis and contained dark brown viscous material, and its inner surface was coated by multiple adherent blood clots [Figure 1]c.

Microscopically, the mass was composed of a thick muscular cyst wall lined with benign endometrial glands and endometrial stroma, with an arrangement resembling endometrium. The endometrial glands had proliferative to hyperplastic features and the cystic wall consisted of thickened smooth muscle bundles that resembled myometrium [Figure 2].{Figure 2}


Uterus-like masses are a rare entity of uncertain histogenesis. Most arise within the ovary, but extraovarian cases have been described. Uterus-like masses should be differentiated from adenomyomas, which lack a uterus-like organization. The first uterine-like mass was documented by Cozzutto in 1981. [1] described a mass originating from stromal cells due to smooth muscle cell metaplasia, possibly due to the effect of estrogen. Fibroblasts and smooth muscle cells appear to be closely related to myofibroblasts and possibly participate in the transitional stage. [1]

A uterus-like mass in the ovary with central endometriosis was first described by Cozzutto in 1981, [1] and similar lesions in the ovary, uterine cervix, uterosacral ligament, broad ligament, small intestine, small bowel mesentery, conus medullaris, and scrotum have since been reported. [2],[3],[4],[5],[6],[7],[8]

A review of these cases showed that they occurred in women aged 11-59 years (average age 35 years). Mass sizes ranged from 2.5 to 16 cm with an average of 8 cm. To our knowledge, the present lesion has been the only one reported with a giant uterus-like mass till date.

Certain cases presented with complaints of lower abdominal pain with/without bleeding, and others were found incidentally during surgery or follow up; it is seldom presented as a palpable mass; sometimes it is presented with paresthesia and weakness of the legs. In all the cases are involved thick muscular walled masses with a central cavity or multicystic space, resembling a uterus. [9]

The histogenesis of uterus-like masses remains uncertain. Presently, three theories have been proposed: 1) metaplastic change, 2) congenital anomaly and 3) heterotopia.

The metaplasia theory is supported by the results of the following studies. Using a cytogenetic analysis, Verhest et al. [4] revealed a clonal chromosome deletion 2p21 and suggested that the uterus-like mass was a true neoplasm. Pai et al. [3] found that there was a close relationship among uterus-like mass of the ovary, breast cancer and elevated serum CA125, and that the uterus-like mass was a hormone-dependent lesion as well as a form of endometriosis.

Others authors [1],[3],[6] have also favored the theory that these masses may be the result of congenital malformations due to either a defect in fusion of the Mullerian ducts or a true partial duplication of the Mullerian system, supporting the finding that congenital abnormalities of the renal system have been associated with some of these cases. The sub-coelomic mesenchyme transformation theory challenges the Mullerian fusion defect hypothesis by noting the varied sites in which this entity has occurred, including the scrotum. [10] Ahmed et al. [5] proposed that some uterus-like masses might originate from the peritoneal mesothelium and its subjacent connective tissue and these tissues could retain the potential to produce different Mullerian structures such as the uterus and fallopian tubes.

Peterson et al. [6] reported a 12-year-old female patient with an ileal uterus-like mass, as well as multiple lower intestinal and urogenital tract anomalies and a past history of sacrococcygeal teratoma. These authors favored a theory of heterotopia as an explanation for this lesion, emphasizing that neither the metaplastic nor malformational theories were completely satisfactory.

In conclusion, we consider that the metaplastic theory best fits with our observations in the present case as both glandular and stromal smooth muscle cells proliferated as a true neoplasm rather than as an anomaly.


1Cozzutto C. Uterus-like mass replacing ovary. Report of a new entity. Arch Pathol Lab Med 1981;105:508-11.
2Horie Y, Kato M. Uterus-like mass of the small bowel mesentery. Pathol Int 2000;50:76-80.
3Pai SA, Desai SB, Borges AM. Uterus-like masses of the ovary associated with breast cancer and raised serum CA125. Am J Surg Pathol 1998;22:333-7.
4Verhest A, Simonart T, Noel JC. A unique clonal chromosome 2 deletion in endomyometriosis. Cancer Genet Cytogenet 1996;86:174-6.
5Ahmed AA, Swan RW, Owen A, Kraus FT, Patrick F. Uterus-like mass arising in the broad ligament: a metaplasia or Mullerian duct anomaly? Int J Gynecol Pathol 1997;16:279-81.
6Peterson CJ, Strickler JG, Gonzalez R, Dehner LP. Uterus-like mass of the small intestine. Heterotopia or monodermal teratoma? Am J Surg Pathol 1990;14:390-4.
7Rougier A, Vital C, Caillaud P. Uterus-like mass of the conus medullaris with associated tethered cord. Neurosurgery 1993;33:328-31.
8Scully RE. Smooth muscle differentiation in genital tract disorders (Editorial). Arch Pathol Lab Med 1981;105:505-7.
9Kim MJ, Sang Hee Seok. Uterus-Like mass with features of an extrauterine adenomyoma. Korean J Pathol 2007;4:347-51.
10Redman R, Wilkinson EJ, Massoll NA. Uterus-like mass with features of an extrauterine adenomyoma presenting 22 years after total abdominal hysterectomy-bilateral salpingo-oophorectomy: A case report and review of the literature. Arch Pathol Lab Med 2005;129:1041-3.