Management of Septated Liver Cysts
A septated liver cyst requires immediate MRI characterization to distinguish benign hemorrhagic cysts from mucinous cystic neoplasms (MCNs), and surgical resection is mandatory when worrisome features are present. 1, 2
Initial Diagnostic Approach
Obtain MRI as the first-line imaging modality for any septated liver cyst, as it provides 94-98% specificity for MCN diagnosis when multiple worrisome features are present and is superior to CT for characterizing cyst contents. 1, 2, 3
Key MRI Features to Assess
Major worrisome features (each requires careful evaluation): 2, 4
- Thick septations (>2mm) - septations arising from the cyst wall without external indentation have very high association with MCN 1
- Mural nodularity or solid components 1, 2
- Wall enhancement on contrast imaging 1
Minor worrisome features include: 2, 4
- Upstream biliary dilatation
- Thin septations
- Internal hemorrhage
- Perfusional changes
- Fewer than 3 coexistent hepatic cysts
Management Algorithm
If ≥1 Major Feature + ≥1 Minor Feature Present:
Proceed directly to complete surgical resection - this combination carries 94-98% specificity for MCN, which has a 3-6% risk of invasive carcinoma and high recurrence rates (0-26%) after incomplete resection. 1, 2, 4
- Complete excision is the gold standard - fenestration alone is associated with higher tumor recurrence rates 1
- Enucleation with free margins is acceptable for centrally located tumors 1
- Major liver resections including extended hemihepatectomy may be necessary for complete removal 1
If No Worrisome Features (Hemorrhagic Simple Cyst):
Conservative management is appropriate when imaging shows: 2, 3, 4
- Heterogeneous hyperintense signal on both T1- and T2-weighted sequences with fluid-fluid levels representing blood-filled lakes between septa 2
- Hyperechoic mobile material (clots) on ultrasound 4
- Lack of enhancement on contrast-enhanced ultrasound - this is the critical distinguishing feature from MCN 3, 4
These typically resolve spontaneously within days to weeks. 3
If Symptomatic Simple Cyst Without Malignant Features:
Laparoscopic fenestration (deroofing) is the preferred treatment, with 92.5% symptom relief and <8% recurrence rate. 3, 5
- Aspiration sclerotherapy has higher recurrence (84.7%) but can be used for initial palliation to confirm symptoms are cyst-related before definitive surgery 3
Critical Clinical Context
MCNs predominantly occur in middle-aged women and typically present in the left liver lobe with symptoms (pain, fullness, early satiety) in 86% of cases. 4
Polycystic liver disease (PLD) should be considered if >10 hepatic cysts are present, which may have septations from prior hemorrhage or infection. 2, 3
Common Pitfalls to Avoid
Do not mistake hemorrhagic septations for malignancy - true MCNs have thick septations with nodularity and enhancement, whereas hemorrhagic cysts show hyperintense septations on T1-weighted imaging without enhancement on contrast studies. 2, 3, 4
Do not use CT as the primary diagnostic modality - it has limited ability to assess cyst contents and differentiate benign from malignant septations compared to MRI. 2
Do not perform prophylactic intervention for asymptomatic cysts - even large cysts (>8 cm) have extremely low absolute risk of complications given that simple hepatic cysts occur in up to 18% of the population. 3
20-50% of MCNs are not properly identified before surgery, so maintain high clinical suspicion when worrisome features are present and involve a multidisciplinary team including hepatogastroenterologists, abdominal radiologists, and abdominal surgeons. 1