From the Guidelines
A decidualized endometrioma is an endometrioma that has undergone decidualization, a process where the endometrioma enlarges and develops rounded vascularized papillary projections along a smooth wall, mimicking malignancy, in response to hormonal progesterone stimulation.
Characteristics of Decidualized Endometriomas
- Can be difficult to diagnose in pregnancy due to loss of typical appearance 1
- May enlarge and develop rounded vascularized papillary projections along a smooth wall, mimicking malignancy 1
- Can be mistaken for other benign lesions, such as mucinous cystadenomas, or borderline tumors 1
Diagnosis and Differentiation
- US-based ovarian scoring systems, such as the ADNEX model, may be used to assess adnexal lesions in pregnant patients, but their application is limited and subjective assessment may perform best 1
- Histopathologic diagnosis is necessary to confirm the presence of an endometrioma, as US findings can be non-specific 1
Clinical Context
- Endometriomas are a type of adnexal lesion that can occur in pregnancy, with an incidence ranging from 1% to 6% 1
- The majority of adnexal lesions in pregnancy are benign and can be accurately characterized via US 1
From the Research
Definition of Decidualized Endometrioma
- A decidualized endometrioma is a type of ovarian endometrioma that undergoes decidualization, a process of endometrial change in pregnancy, in response to hormonal stimulation 2, 3, 4.
- Decidualization can cause changes in the appearance of the endometrioma, making it resemble a malignant tumor on ultrasound or other imaging modalities 2, 3, 5.
Characteristics of Decidualized Endometrioma
- Decidualized endometriomas often present with a cystic mass and abundant blood flow signals on ultrasound 2, 5.
- They may contain papillary projections, which can be vascularized, and have a ground-glass or low-level echogenicity of the cyst fluid 5.
- The number of cyst locules can vary, and most decidualized endometriomas do not have ascites 5.
Diagnosis and Management
- Diagnosis of decidualized endometrioma can be made using fine needle aspiration cytology and confirmed by immunocytochemistry 6.
- Ultrasound and magnetic resonance imaging (MRI) can be helpful in differential diagnosis and monitoring of decidualized endometriomas 2, 3, 5.
- Conservative management, including expectant management and serial monitoring, may be adopted if decidualized endometriosis is suspected 2, 3.
- In some cases, surgical removal of the decidualized endometrioma may be necessary, especially if there are concerns about malignancy or if the patient is symptomatic 2, 5.