Uterus
Stromal tumors
Adenosarcoma

Author: Özlem Özen, M.D. (see Authors page)
Editor: Ayse Ayhan, M.D., Ph.D.

Revised: 26 March 2018, last major update March 2018

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Uterus stromal tumors adenosarcoma

Cite this page: Özen, Ö. Adenosarcoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/uterusadenosarcoma.html. Accessed April 20th, 2018.
Definition / general
Essential features
  • First reported and described by Clement and Scully in 1974 as a mixed tumor of the uterus (Cancer 1974;34:1138)
  • In 1979, two additional cases were reported and the term Müllerian adenosarcoma became universally recognized (Cancer 1979;43:1439)
Terminology
  • Synonym: Müllerian adenosarcoma
ICD-10 coding
Epidemiology
Sites
Etiology
Clinical features
Diagnosis
  • Best made by applying routine histopathologic criteria
  • Immunohistochemistry has only limited role
Prognostic factors
Case reports
  • 28 year old woman with adenosarcoma with sarcomatous overgrowth in which tumor resembling a smooth muscle tumor and diagnosed as "a clear cell leiomyoma" (Int J Gynecol Pathol 2014;33:573)
  • 28 year old woman with cervical adenosarcoma who was treated by fertility preserving surgery and successfully delivered a child 18 months later (Case Rep Obstet Gynecol 2017;2017:4187416)
  • 39 year old woman with adenosarcoma with sarcomatous overgrowth in the uterine cervix and pelvic lymph node involvement (Int J Surg Case Rep 2016;27:155)
  • 45 year old woman with postmenopausal bleeding (Case of the Week #451)
  • 55 year old woman with solitary brain metastasis without any extracranial recurrence from uterine adenosarcoma with sarcomatous overgrowth after 4 years of primary treatment (Brain Tumor Res Treat 2016;4:138)
Treatment
Gross description
Gross images

Images hosted on PathOut server:

Image contributed by Aysha Mubeen, M.D.

Case of the Week #451

Microscopic (histologic) description
  • Low power examination reveals a biphasic tumor composed of benign appearing epithelium and a cellular low grade malignant stroma
  • Condensation (cuffing) of the cellular stroma around glands which may be cystically dilated is a typical feature
  • Displays a phyllodes-like morphology with intraluminal polypoid projections of the stroma
  • Epithelium of the glands is usually endometrioid but often shows mucinous, squamous or tubal metaplasia and may show mild to moderate atypia
  • Stroma is a low grade sarcoma, frequently with no specific line of differentiation, although some consider it to resemble endometrial stromal sarcoma
  • Stroma may show hyalinization, elastosis, edema or myxoid change
  • May also show heterologous elements (such as immature cartilage and skeletal muscle), sex cord-like differentiation or smooth muscle metaplasia.
  • Mitotic threshold for the diagnosis of adenosarcoma is ≥ 2 MF / 10 HPF in stromal cells
  • Adenosarcoma with sarcomatous overgrowth is defined as the presence of sarcoma (without any epithelial component) in > 25% of the tumor, most frequently as homologous poorly differentiated sarcoma
  • Heterolog elements, most commonly rhabdomyosarcoma, may be present
  • Sarcomatous overgrowth is associated with deeper myometrial involvement and lymphovascular invasion (Mutter: Pathology of the Female Reproductive Tract, 3rd Edition, 2014, IARC: WHO Classification of Tumours of the Female Reproductive Organs, 4th Edition, 2014, Arch Pathol Lab Med 2016;140:286)
Microscopic (histologic) images

Images hosted on PathOut server:

Images contributed by Ayse Ayhan, M.D., Ph.D.
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High-grade sarcoma areas

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Mitotic figures in malignant stromal cells

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The sarcomatous component forms intraglandular papillae


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Periglandular cellular stroma resulting in cambium-like layer

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An area with squamous metaplasia

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The sarcomatous component forms intraglandular papillae and depicts periglandular stromal condensation

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Adenosarcoma with sarcomatous overgrowth

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Cystically dilated benign-appearing gland


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Subtle periglandular cuff

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Another area showing an periglanduler cuff

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Heterologous elements

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Periglandular condensation

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Intraglandular papillae and cambium-like layer

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Higher grade sarcomatous areas



Images contributed by Aysha Mubeen, M.D.

Case of the Week #451

Cytology images

Images hosted on other servers:
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Denuded malignant cells with variable sizes

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Dense clusters of polymorphic tumor cells

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Long oval, hyperchromatic nuclei with 1+ nucleoli (Pap)

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Partly denuded tumor cells with fragile cytoplasm

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Tumor cells have variable sizes

Positive stains
Differential diagnosis
Board review question #1
    Adenosarcoma:

  1. Differs from adenofibroma by showing marked cellularity (including periglandular cuffs), any degree of stromal cell atypia and ≥ 2 MF / 10 HPF
  2. Is associated with a good outcome even though myometrial invasion and sarcomatous overgrowth are present.
  3. Is classified as an “adenosarcoma with sarcomatous overgrowth” if a high grade sarcoma is seen in > 10% of the tumor.
  4. Is composed of glands with severe cytological atypia and a cellular low grade malignant stroma.
  5. Never shows any heterologous component while almost half of carcinosarcomas show this feature.
Board review answer #1
A. Differs from adenofibroma by showing marked cellularity (including periglandular cuffs), any degree of stromal cell atypia and ≥ 2 MF / 10 HPF. Adenosarcoma is a biphasic tumor composed of benign appearing epithelium and a cellular low grade malignant stroma. The main differential diagnosis includes adenofibroma and it differs from adenofibroma by showing marked cellularity (including periglandular cuffs), any degree of stromal cell atypia and ≥ 2 MF / 10 HPF. The tumor is classified as an adenosarcoma with sarcomatous overgrowth when at least 25% of the tumor contains a high grade sarcomatous component. Adenosarcoma is frequently associated with a good outcome if confined to the endometrium. Otherwise deep myometrial invasion and the presence of sarcomatous overgrowth predict a poor prognosis. Heterolog elements, most commonly rhabdomyosarcoma, may also be present especially in adenosarcoma with sarcomatous overgrowth.
Board review question #2
    Adenofibroma:

  1. Can be diagnosed in curettings or biopsy materials.
  2. Contains rare mitotic figures (< 2 MF / 10 HPF).
  3. Is a benign pure mesodermal tumor composed of endometrial stromal or fibroblastic cells.
  4. Requires immunohistochemistry for diagnosis.
  5. Typically shows periglandular stromal condensation and mild stromal cell atypia.
Board review answer #2
B. Contains rare mitotic figures < 2 MF / 10 HPF. Adenofibroma is a benign form of mixed mesodermal tumor composed of an admixture of Müllerian epithelium and stroma, both components being benign. It should be diagnosed only in a well sampled tumour removed totally and thorough microscopic examination is needed since the diagnosis can be made only by histopathology. The tumor is typically characterized by showing no periglandular stromal condensation and no stromal cell atypia with < 2 MF / 10 HPF.
Board review question #3
Which of the following is a poor prognostic factor for uterine adenosarcoma?

A. A+C
B. Cellular atypia
C. Deep myometrial invasion
D. Increased mitotic activity and presence of tumor necrosis
E. Sarcomatous overgrowth
Board review answer #3
A. (A+C)

Poor prognostic factors are presence of sarcomatous overgrowth and deep myometrial invasion.