• Prior recommendations for pelvic MRI
  
• Optional recommendation (ESUR Guidelines)
  
• Recommended sequences and planes (ESUR Guidelines)
  
• Introduction to Endometrial Carcinoma

Endometrial carcinoma is the most common tumor of the female genitourinary system, with MRI being the technique of choice for local staging. 

• New FIGO 2023 Classification for Staging Endometrial Cancer

Unlike the previous classification, it establishes histological and molecular findings as key elements for tumor staging, which makes it impossible to include this information in the radiological report.

• Myometrial Invasion

The 2023 FIGO guidelines recommend expressing the percentage of myometrial invasion using three categories, given their implications for surgical management: none, <50%, or ≥50%.

• Myometrial Invasion – Why? How to calculate? 

According to the 2021 ESGO guidelines, the presence of myometrial invasion requires sentinel lymph node biopsy, and if the myometrial invasion is ≥50%, and the sentinel lymph node localization is not feasible, pelvic lymphadenectomy is necessary given the high risk of lymph node metastasis in this patient group.

The calculation is performed by drawing two lines: one measuring the total thickness of the myometrium and the other measuring the maximum myometrial tumor extension. 

• Myometrial Invasion – Importance of DWI sequences 

DWI sequences are needed to calculate the % of myometrial invasion when endometrial carcinomas are isointense relative to the surrounding myometrium in T2-weighted sequences.

DWI enhances the diagnostic accuracy of MRI in detecting myometrial invasion, particularly in clinical scenarios where uterine morphology is distorted.

• Disease confined to the uterus - radiological report 

2023 FIGO Staging System, unlike the previous classification, establishes histological and molecular findings as key elements for tumor staging, which makes it impossible to provide a radiological stage in stages I and II.

• Cervical Stromal Invasion

Cervical stromal invasion alters the tumor staging (IIA – no aggressive histology or IIC – aggressive histology). According to the 2021 ESGO guidelines, adjuvant EBRT is recommended in case of cervical stromal invasion. 

• Cervical Stromal Invasion – Importance of DWI sequences

DWI sequences facilitate the detection of small cervical or vaginal implants that might go unnoticed on anatomical sequences.

• Parametrial Invasion

Parametrial invasion alters the tumor staging (IIIB1 according to FIGO 2023). DWI imaging can help avoid the overestimation of inflammation and improve the accuracy of T2 – weighted sequences.

• • • Lymph Node Detection

DWI sequences help detect lymph node; however, to differentiate benign from malignant nodes, the most widely used criterion is the short axis of the node or its morphology.

• • • Presence of Metastatic Disease

DWI sequences aid in identifying possible ovarian extension or foci of pelvic peritoneal carcinomatosis.