|Year : 2015 | Volume
| Issue : 4 | Page : 967-969
Cystic adenomatoid tumor of the uterus
Varsha Manucha1, Azniv Azar1, James M Shwayder2, Joseph L Hudgens2, Jack Lewin1
1 Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi, USA
2 Department of Obstetrics and Gynecology, University of Mississippi Medical Center, Jackson, Mississippi, USA
|Date of Web Publication||15-Feb-2016|
Department of Pathology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216
Source of Support: None, Conflict of Interest: None
We present a case of a cystic adenomatoid tumor in a 40-year-old woman. The tumor was an intramural multicystic mass, histologically similar to a multicystic mesothelioma. Cystic adenomatoid tumors of the uterus are extremely rare. They present with a wide differential diagnosis in radiology. The tumors are known to be benign and awareness of this rare entity is the key to its diagnosis for a pathologist.
Keywords: Adenomatoid tumor, cystic adenomatoid tumor, uterus
|How to cite this article:|
Manucha V, Azar A, Shwayder JM, Hudgens JL, Lewin J. Cystic adenomatoid tumor of the uterus
. J Can Res Ther 2015;11:967-9
| > Introduction|| |
An adenomatoid tumor arising in the uterus is not well-recognized and may be mistaken for other benign or malignant neoplasms. The tumors are thought to be of mesothelial origin and have been commonly described as small nodular subserosal lesions. We report a rare case of intramural cystic adenomatoid tumor of the uterus in a 40-year-old woman.
| > Case report|| |
A 40-year-old woman presented with left lower quadrant pain to the out-patient office. Physical examination revealed tenderness in the left lower quadrant on deep palpation and was otherwise unremarkable. She had a prior history of appendectomy and left salpingectomy. An office ultrasound of the uterus showed an unusual appearance of the myometrium with large cystic spaces and septations with the absence of Doppler flow [Figure 1]. Magnetic resonance imaging performed for further characterization of the lesion revealed a well-defined multiloculated cystic lesion (4.1 cm × 3.1 cm × 5 cm) within the myometrium of the uterus with multiple thin enhancing septae [Figure 2]. No solid or mural components were seen. There was no connection with the endometrial cavity. The differential diagnosis including large degenerating intramural fibroid, congenital uterine cyst, intramyometrial hydrosalpinx, cystic endosalpingiosis, cystic adenomatoid tumor, and the echinococcal cyst was considered. A separate multiloculated cyst was noted in the right adnexa that represented a hemorrhagic cyst or involuting corpus luteal cyst. Other organs were within normal limits. A hysterectomy with right salpingo-oophorectomy was performed. On gross examination, the uterus was slightly enlarged (7.0 cm × 7.3 cm × 5.2 cm; 128 g) with a smooth serosal surface. Bivalving the uterus revealed a multiloculated cyst (4.7 cm × 3.8 cm × 2.8 cm) filled with serous, clear fluid. The cyst was located on the left wall of uterus involving both anterior and posterior myometrium. The luminal surface of the cyst was smooth and tan-pink with the absence of any papillary projections or solid nodules [Figure 3]. The endometrium was 0.2 cm in thickness. A few nabothian cysts were present in the cervix.
|Figure 1: Uterus with large cystic lesion and septations with absence of Doppler flow (ultrasound)|
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|Figure 2: Multiloculated cystic lesion within the interstitium of the uterus with multiple thin enhancing septae (magnetic resonance imaging)|
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|Figure 3: Intramural multiloculated cystic mass with smooth luminal surface (gross image)|
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On microscopic examination, the myometrial cyst was mostly denuded of lining epithelium except in a couple of sections where it was lined by cuboidal to flattened epithelium [Figure 4]a]. The surrounding myometrium was remarkable for the presence of several cavernous, thin-walled vascular structures reminiscent of a cavernous lymphangioma [Figure 5]a]. One section revealed a microscopic haphazard proliferation of bland tubular structures (measuring 4 mm in greatest dimension) in the myometrium adjacent to the cyst [Figure 6]a]. The endometrium was weakly proliferative and the ovary showed an unrelated benign hemorrhagic cyst and the fallopian tube was unremarkable. Adequately controlled immunohistochemical stains showed the lining epithelial cells of the cyst and the glandular proliferation to be positive for calretinin [Figure 4]b and [Figure 6]b], broad spectrum keratin (AE1/AE3), and negative for CD31 and estrogen receptor (ER). The cavernous vascular structures surrounding the cyst were positive for CD31 and negative for calretinin [Figure 5]b].
|Figure 4: Flattened mesothelial cells lining the cyst, positive for calretnin ((a) H and E, ×200; (b) Calretinin, ×200)|
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|Figure 5: Large cavernous spaces in the myometrium (arrow mark), positive for CD31 (arrow mark); luminal surface (solid arrow) ((a) H and E, ×200; (b) CD31, ×200)|
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|Figure 6: Microscopic adenomatoid tumor positive for calretenin (arrow) ((a) H and E, ×200; (b) Calretenin, ×200)|
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| > Discussion|| |
Adenomatoid tumors of the uterus are rare and have been found in 1.2% of hysterectomy specimens.  They are typically described as incidental findings in uteri removed for other causes in women of reproductive age group. , The frequent association between solid type adenomatoid tumors and nodular proliferation of smooth muscle (leiomyo-adenomatoid tumor) and leiomyomas, frequently result in its misdiagnosis as leiomyomas macroscopically possibly resulting in its under sampling and false low incidence. , The rare coexistence of the tumor with endometrioid carcinomas and clinical association with immunosuppressed renal transplant status is possibly incidental. ,,
The origin of adenomatoid tumors was originally thought to be influenced by hormonal stimulation because of its predilection in the genital tract and common embryological origin from the coelomic thickening. However, the absence of expression of estrogen or progesterone receptors argues against this theory.  More recently, the histogenesis of the adenomatoid tumors is attributed to two different processes; mesothelial type arising from serosal mesothelial cells and adenomatoid type arising from immature Müllerian mesenchymal tissue that differentiate toward submesothelial cells and eventually mesothelial cells.  The immunohistochemical results and electron microscopic studies support the theory of histogenesis of the adenomatoid tumor from mesothelium. ,
Macroscopically the tumors have been described as solid, either nodular or diffuse ranging from 0.2 to 3.5 cm in greatest dimension located in the subserosa or nearby the subserosa of the uterine cornua or the outer wall of the myometrium. , The larger cystic variant of the adenomatoid tumor is extremely rare. Nogales et al.  described 60 cases of adenomatoid tumors of the uterus, of which 56 were the small solid type and 4 were the large cystic type. The cystic variant ranged in the size range from 7 to 10 cm and focally exhibited the presence of short papillae and serosal involvement. This group could be confused with intramural leiomyomas with mucoid degeneration or with adnexal masses on sonography. Four distinctive histologic types (adenoid, angiomatoid, solid, and cystic) have been identified, but a combination of growth patterns can be present.  The tumor in our case was entirely intramural in location, well circumscribed, and lacked any papillae or serosal involvement. Microscopically, the tumor was composed of multiple cysts lined by bland cuboidal epithelium intimately associated with dilated vascular channels, resembling a lymphangioma. Careful microscopic examination of multiple sections revealed a small adenomatoid tumor composed of small tubules growing within smooth muscles (4 mm in maximum dimension) in a pseudoinfiltrative pattern. The presence of bland and cuboidal epithelial cells argued against it being a metastatic carcinoma. The tumor's mesothelial origin was proven by immunohistochemistry.
The treatment of the adenomatoid tumor is simple excision of the tumor, if the uterus is not going to be removed for other reasons. So far, there is no case report of malignant degeneration or recurrence in these tumors.
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Conflicts of interest
There are no conflicts of interest.
| > References|| |
Tiltman AJ. Adenomatoid tumours of the uterus. Histopathology 1980;4:437-43.
Tiszlavicz L. Adenomatoid tumor of the uterus. Report of ten cases. Am J Clin Pathol 1981;76:627-35.
Quigley JC, Hart WR. Adenomatoid tumors of the uterus. Acta Pathol Jpn 1980;30:883-906.
Sarma NH, Srinivasulu M, Suchitra MJ. Leiomyoadenomatoid tumor of the uterus: Report of a rare entity and review of the literature. Indian J Pathol Microbiol 2014;57:450-2.
Nogales FF, Isaac MA, Hardisson D, Bosincu L, Palacios J, Ordi J, et al.
Adenomatoid tumors of the uterus: An analysis of 60 cases. Int J Gynecol Pathol 2002;21:34-40.
Cheng CL, Wee A. Diffuse uterine adenomatoid tumor in an immunosuppressed renal transplant recipient. Int J Gynecol Pathol 2003;22:198-201.
Livingston EG, Guis MS, Pearl ML, Stern JL, Brescia RJ. Diffuse adenomatoid tumor of the uterus with a serosal papillary cystic component. Int J Gynecol Pathol 1992;11:288-92.
Mai KT, Yazdi HM, Perkins DG, Isotalo PA. Adenomatoid tumor of the genital tract: Evidence of mesenchymal cell origin. Acta Morphol Hung 1991;39:309-20.
Suzuki T, Yoshida Y, Kaku T, Kikuchi K, Mori M. Adenomatoid tumor of the uterus. Ultrastructural, histochemical, and immunohistochemical analysis. Arch Pathol Lab Med 1985;109:1049-51.
Palacios J, Suárez Manrique A, Ruiz Villaespesa A, Burgos Lizaldez E, Gamallo Amat C. Cystic adenomatoid tumor of the uterus. Int J Gynecol Pathol 1991;10:296-301.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]