How does treatment of a hepatic adenoma greater than 10 cm change in a patient who is 24 weeks pregnant?

Management of Hepatic Adenoma >10 cm Diagnosed at 24 Weeks Pregnancy

For a hepatic adenoma greater than 10 cm diagnosed at 24 weeks gestation, close surveillance with ultrasound or MRI monitoring is essential, with strong consideration for intervention if the tumor enlarges, shows signs of hemorrhage, or becomes symptomatic, as these large adenomas carry substantial risk of life-threatening rupture during the third trimester and delivery. 1

Risk Stratification at This Gestational Age

The situation is particularly high-risk because:

• Hemorrhage risk is substantial with adenomas 6.5-17 cm, with historical data showing that 15 women with tumors in this size range experienced HCA-related hemorrhage, and bleeding occurred predominantly in the third trimester (7 cases), during labor (2 cases), and postpartum (5 cases). 1

• At 24 weeks, the patient is entering the highest-risk period, as the third trimester represents the time when most pregnancy-related adenoma complications occur due to increased hormonal stimulation, increased intra-abdominal pressure, and direct contact with the gravid uterus. 1

• The adenoma is already twice the size threshold (>5 cm) that guidelines recommend treating prior to pregnancy, placing this patient in a significantly elevated risk category. 1

Surveillance Protocol

Implement intensive monitoring with the following schedule:

• Ultrasound or MRI surveillance should be performed regularly to detect tumor enlargement, as tumors that enlarge are more likely to bleed and may require intervention. 1

• Each trimester monitoring is the minimum standard, though more frequent imaging (potentially monthly in the third trimester) may be warranted given the large size at presentation. 1

• Continue surveillance through 12 weeks postpartum, as HCAs continue to pose risk during the period of rapid normalization of sex hormone levels. 1

Intervention Thresholds

Be prepared to intervene if any of the following occur:

• Tumor enlargement of >20% from baseline, as this indicates hormone-sensitive growth and increased hemorrhage risk. 1

• Development of symptoms including abdominal pain, which may herald impending rupture. 1

• Any signs of hemorrhage on imaging or clinically. 1

Intervention Options During Pregnancy

If intervention becomes necessary:

• Transarterial embolization has been successfully performed at 26 weeks gestation in one case where an HCA grew to >7 cm, with good maternal and fetal outcomes. 1

• Radiofrequency ablation was successfully applied in the first trimester in one case, though at 24 weeks this option may be more challenging. 1

• Surgical resection can be performed during pregnancy if rapidly enlarging or complicated by rupture, preferably in the second trimester, though major hepatobiliary surgery has been safely performed in the third trimester. 1, 2

• Laparoscopic resection has been reported as feasible during pregnancy (at 16 weeks in one case), though at 24 weeks with a 10+ cm lesion, open surgery may be more appropriate if intervention is needed. 3

Delivery Planning

Modify delivery management to minimize hemorrhage risk:

• Plan for elective cesarean section if the tumor remains stable but large, as two cases with enlarging tumors were managed with elective cesarean at 34 and 36 weeks with good outcomes. 1

• Prevent prolonged second stage of labor and consider assisted delivery to avoid excessive Valsalva maneuvers, which increase intra-abdominal pressure and hemorrhage risk. 1

• Timing of delivery should balance fetal maturity against maternal hemorrhage risk, with consideration for delivery at 36-37 weeks if the tumor remains stable. 1

• Have interventional radiology and hepatobiliary surgery immediately available at the time of delivery, as emergency intervention may be required. 1

Critical Pitfalls to Avoid

• Do not perform biopsy of the lesion during pregnancy, as this has precipitated rupture of even a 3.5 cm lesion in one reported case. 3

• Do not adopt a purely conservative "wait and see" approach without intensive surveillance, as this size adenoma (>10 cm) exceeds the safety threshold established in contemporary studies. 1, 4

• Do not delay intervention if the tumor shows growth or symptoms, as maternal mortality with free rupture is 5-10% compared to <1% with elective resection, and historical series showed maternal and fetal deaths approaching 50% with spontaneous rupture. 3, 5, 6

Multidisciplinary Team Involvement

Coordinate care with:

• Maternal-fetal medicine specialists for high-risk obstetric management. 1

• Hepatobiliary surgeons for surgical planning if intervention becomes necessary. 1

• Interventional radiologists for potential embolization procedures. 1