Antenatally-detected liver cysts: Causes and characteristics, indications for intervention.

AIM: The prevalence of antenatally-detected hepatic cysts is increasing owing to increased use of maternal ultrasonography (USS). Diagnostic precision, however, is challenging and subsequently there is no clear consensus on postnatal management. The aim of the study was to evaluate the natural history and long-term follow up of congenital simple hepatic cysts.

METHODS

Single-center review of prospectively-maintained dataset collected over a 25-year period. Data are quoted as median (range).

RESULTS

In the period 1991-2016, 31 infants presented with an antenatally-detected cyst which, on postnatal imaging, was likely confirmed as a simple parenchymal hepatic cyst. These together with a further infant who presented at 4 days without any antenatal imaging comprised the study group (n = 32). Gestational age at detection was 23 (13-38) weeks. Maximum antenatal cyst diameter was measured at 19 (4-120) mm. Only the largest required percutaneous aspiration at 35 weeks' gestation being associated with polyhydramnios. Postnatally, serial USS was performed alongside MRI/CT or liver scintigraphy if there was diagnostic doubt. Initial maximum cyst diameter was 30 (12-120) mm. Five infants came to surgical intervention and this included excision ± marsupialization (n = 4), and a cyst-jejunostomy en Roux in one child thought to have a connection with the biliary tract on intraoperative cholangiography. The mucosal lining in two cysts showed areas of squamous metaplasia, with one more showing an intact squamous lining probably more consistent with an epidermoid cyst. In the remaining cases (n = 27), all asymptomatic, serial USS showed volume maintenance (n = 16) actual volume regression (n = 4) and resolution (n = 7). Median follow-up in these cases was 42 (4-252) months.

CONCLUSION

This is the largest case series to date of antenatally-detected simple hepatic cysts. Most can be managed conservatively, and relative regression or resolution is likely. Surgical intervention should be reserved for those: that are large at the outset; show rapid cyst growth - these being typically exophytic in nature; wall irregularity or where there is diagnostic doubt.

TYPE OF STUDY: Case series.

LEVEL OF EVIDENCE: Level IV.