From the Guidelines
Focal nodular hyperplasia (FNH) typically requires no treatment as it is a benign liver lesion that rarely causes symptoms or complications. The standard approach for asymptomatic FNH is observation, with regular imaging follow-up (usually ultrasound or MRI) every 6-12 months initially to confirm stability, which can be extended to longer intervals once stability is established 1. Surgical resection is reserved only for rare cases with significant symptoms like persistent abdominal pain, rapid growth, or diagnostic uncertainty. Unlike hepatic adenomas, FNH has no malignant potential and doesn't rupture or bleed, making conservative management appropriate. Women with FNH can safely continue oral contraceptives as these medications don't affect FNH growth or behavior, unlike their effect on hepatic adenomas 1. If incidental FNH is discovered during imaging for other reasons and is asymptomatic with typical radiographic features, no specific intervention or lifestyle modification is necessary. Some key points to consider in the management of FNH include:
- The benign nature of FNH relates to its origin as a hyperplastic response to a pre-existing vascular abnormality rather than a true neoplasm.
- Pregnancy is not contraindicated in women with FNH, and vaginal delivery is not associated with increased risks 1.
- Imaging is not routinely recommended to monitor FNH during pregnancy 1.
- The relationship between FNH and estrogen exposure is controversial, but the available evidence suggests that estrogen does not significantly affect FNH growth or behavior 1. Overall, the management of FNH should focus on conservative observation and avoiding unnecessary interventions, unless significant symptoms or complications arise.
From the Research
Treatment Approach for Focal Nodular Hyperplasia (FNH)
The treatment approach for FNH is largely dependent on the symptoms and characteristics of the lesion.
- Asymptomatic patients with FNH do not require treatment, and systematic follow-up is considered the gold standard 2.
- Elective surgery should be considered in symptomatic patients, those with marked enlargement, and in cases where there is uncertainty about the diagnosis 2.
- Surgery for FNH is a safe procedure with low morbidity and very good long-term results, especially concerning quality of life after surgery 2.
- For patients with FNH who are asymptomatic, no further investigation or treatment is required, and they can be managed without invasive investigation or treatment 3.
- In some cases, percutaneous biopsy may be necessary to establish a definitive diagnosis, especially when imaging findings are unclear or when there is a suspicion of malignancy 4, 5.
Diagnostic Considerations
- Magnetic resonance (MR) imaging has higher sensitivity and specificity for FNH than ultrasonography or computed tomography, and is useful for distinguishing FNH from other hypervascular liver lesions 6.
- Typical imaging findings for FNH include a central scar and homogeneous enhancement during the arterial phase of gadolinium-enhanced imaging 6.
- CT and MRI are valuable for the diagnosis of FNH, but definite preoperative diagnosis can be difficult to make, and biopsy guided by ultrasonography may be necessary in some cases 5.