Understanding malignant transformation of endometriosis: imaging features with pathologic correlation

  • Kristin A. RobinsonEmail author
  • Christine O. Menias
  • Longwen Chen
  • Giancarlo Schiappacasse
  • Akram M. Shaaban
  • Melanie P. Caserta
  • Khalid M. Elsayes
  • Wendaline M. VanBuren
  • Candice W. Bolan
Special Section: Endometriosis
Part of the following topical collections:
  1. CME articles



Transformation of benign endometriosis to endometriosis-associated ovarian carcinoma (EAOC) is rare; however, women with endometriosis are four times more likely to develop EAOC which can present 20 years earlier than de novo ovarian cancer. Presenting symptoms are often vague and the radiologist’s role in recognizing EAOC is critical for early detection and treatment. Histopathologic evaluation remains the mainstay for definitive diagnosis.


Using a case-based approach, this article will review the sonographic, CT, and MRI features of EAOC with an emphasis on MRI. Histopathologic correlation of benign and malignant endometriosis will be reviewed.


Multiple factors contribute to the malignant transformation of endometriosis including genetic alterations, hormonal influences, oxidative stress, and inflammation. Malignancy most often occurs in ovarian endometriomas with less common sites involving the rectovaginal septum, rectosigmoid colon, and abdominal wall scars. The most common pathologic subtypes are endometrioid adenocarcinoma and clear cell carcinoma. MRI is the most specific imaging modality for evaluating EAOC. Key MR features include solid enhancing nodules (accentuated by subtraction imaging), nodular septations, loss of T2 shading within the endometrioma, and diffusion restriction.


EAOC is a distinct disease that affects women with benign endometriosis at younger ages than classic ovarian cancer. Understanding the imaging features of malignant transformation of endometriosis is essential for early diagnosis and timely definitive treatment.


Endometriosis-associated ovarian carcinoma Malignant endometriosis Endometriosis Pathology Clear cell carcinoma Endometrioid adenocarcinoma 



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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Kristin A. Robinson
    • 1
    Email author
  • Christine O. Menias
    • 2
  • Longwen Chen
    • 3
  • Giancarlo Schiappacasse
    • 4
  • Akram M. Shaaban
    • 5
  • Melanie P. Caserta
    • 6
  • Khalid M. Elsayes
    • 7
  • Wendaline M. VanBuren
    • 8
  • Candice W. Bolan
    • 9
  1. 1.Department of Diagnostic RadiologyMayo Clinic HospitalPhoenixUSA
  2. 2.Department of Diagnostic Radiology, Abdominal DivisionMayo Clinic HospitalPhoenixUSA
  3. 3.Department of PathologyMayo Clinic HospitalPhoenixUSA
  4. 4.Facultad de Medicina Clínica Alemana - UDDSantiagoChile
  5. 5.Department of Diagnostic RadiologyUniversity of UtahSalt Lake CityUSA
  6. 6.Department of Diagnostic Radiology, Ultrasound DivisionMayo Clinic HospitalJacksonvilleUSA
  7. 7.Department of Diagnostic RadiologyUniversity of Texas MD Anderson Cancer CenterHoustonUSA
  8. 8.Department of Diagnostic Radiology, Ultrasound DivisionMayo Clinic HospitalRochesterUSA
  9. 9.Department of Diagnostic Radiology, Abdominal DivisionMayo Clinic HospitalJacksonvilleUSA

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