Management of Septated Liver Cysts

Initial Diagnostic Approach

The American Association for the Study of Liver Diseases recommends obtaining contrast-enhanced MRI to differentiate between a benign simple cyst with septations versus a mucinous cystic neoplasm (MCN), as septations represent a worrisome feature that requires further characterization 1
MRI with contrast is the preferred imaging modality for characterizing hepatic cysts with worrisome features, as it provides superior tissue characterization compared to CT or ultrasound alone 1

The presence of thick septations or nodularity are major worrisome features for MCN, while thin septations alone are a minor worrisome feature 1
Mural nodules >1 cm are associated with malignancy in MCNs 1
Wall enhancement or calcifications should be assessed on MRI 1
Signal characteristics on T1 and T2 sequences should be evaluated to assess for hemorrhage or protein content 1, 2
The number of coexistent hepatic cysts should be assessed, with <3 cysts being a minor worrisome feature for MCN 1

If MRI shows simple cyst with thin septations only, and no wall enhancement, no thick septations, and multiple other simple cysts are present, this represents a benign simple cyst with septations, and no treatment is needed if asymptomatic 1, 2, 3
The combination of ≥1 major feature (thick septations or nodularity) plus ≥1 minor feature (thin septations, upstream biliary dilatation, internal hemorrhage, perfusional change, or <3 coexistent cysts) should raise concern for MCN, with a 94-98% specificity for MCN 1

Hydatid disease (echinococcosis) must be excluded, particularly if the patient has travel history to endemic areas, and hydatid serology should be reviewed before any aspiration attempt to avoid anaphylaxis 3, 6, 7
For cysts <5 cm, albendazole alone is recommended if hydatid disease is confirmed 3, 6
Never perform liver biopsy if hydatid disease is suspected due to high risk of cyst rupture and anaphylaxis 5

Obtain contrast-enhanced MRI to characterize the septations and assess for worrisome features 1, 5
If worrisome features are present (thick septations, nodularity, wall enhancement), refer to hepatobiliary surgeon for evaluation and likely surgical resection 1, 5
If travel history to endemic areas, check hydatid serology before any intervention 7
If hemorrhagic features on MRI, conservative management is recommended, as symptoms resolve spontaneously 2

Do not rely on ultrasound alone for characterizing septated cysts, as it cannot adequately differentiate benign from malignant features 1
Do not perform aspiration or biopsy before excluding hydatid disease with serology 5, 7
Do not assume all septated cysts are benign – the combination of thick septations with other features requires surgical evaluation 1
Do not use CT as first-line advanced imaging – MRI is superior for tissue characterization of cystic lesions 1
Do not delay surgical referral if multiple worrisome features are present, as MCNs can harbor malignancy 1