From the Guidelines
Borderline lymph nodes on MRI should be further evaluated through follow-up imaging in 3-6 months to monitor for changes in size or characteristics, as they may represent reactive changes or potential malignancy, particularly in the context of endometrial cancer staging 1. When assessing borderline lymph nodes on MRI, it is essential to consider the clinical context, including the patient's medical history, symptoms, and the presence of known malignancy. In the context of endometrial cancer staging, MRI is accurate at identifying surrogate markers of lymph node metastases, such as deep myometrial invasion and cervical stromal involvement 1.
Key Considerations
- Borderline lymph nodes typically measure between 8-10mm in short-axis diameter, which is at the threshold between normal and enlarged.
- Further evaluation through follow-up imaging in 3-6 months is recommended to monitor for changes in size or characteristics.
- Additional imaging modalities like PET-CT may be helpful to assess metabolic activity within these nodes.
- If there is significant clinical suspicion for malignancy, a biopsy may be warranted to obtain a definitive diagnosis.
Clinical Context
In the context of endometrial cancer staging, the presence of borderline lymph nodes may indicate a need for full surgical staging by gynecological surgeons, particularly if surrogate markers of lymph node metastases are present 1. High-grade tumors are at risk for extrauterine spread and therefore warrant full surgical staging by gynecological surgeons. The role of imaging in this subgroup may be to identify extrauterine metastases or spread, which helps plan the surgical approach.
Management Decisions
Radiologists typically describe borderline nodes in their reports with specific measurements and characteristics such as shape, borders, and internal architecture to help clinicians make appropriate management decisions. The significance of borderline lymph nodes depends on the clinical context, including the patient's medical history, symptoms, and the presence of known malignancy. These nodes may represent reactive changes due to infection or inflammation rather than malignancy.
From the Research
Implications of Borderline Lymph Nodes on MRI
- The presence of nodal metastases in borderline lymph nodes can limit therapeutic options and indicate a worse prognosis for patients 2.
- Anatomic imaging, such as MRI, has limited value in depicting small metastatic deposits in normal-sized nodes, and nodal size is a poor criterion for diagnosing nodal metastases 2, 3.
- Contrast-enhanced MR imaging of lymph nodes can be a non-invasive method for analyzing the lymphatic system and detecting lymph node metastases, independent of nodal size 2, 3.
- The use of lymphotropic contrast media, such as ultrasmall superparamagnetic iron oxide particles or Gadofluorine M, can improve the detection of lymph node metastases on MRI 3.
- In some cases, mullerian inclusion cysts in lymph nodes may be metastases from serous borderline tumors of the ovary, rather than benign inclusions 4.
- MRI can be used to evaluate the central lymphatic system, including lymph nodes and lymphatic vessels, and can be useful for diagnostic purposes or pre-procedural planning 5.
- The management of borderline axillary lymph nodes in breast cancer patients is unclear, and core needle biopsy may be disruptive rather than helpful in some cases 6.