Lower Abdominal and Periumbilical Pain in a Patient With Focal Nodular Hyperplasia of the Liver: A Case Report and Literature Review.

Focal nodular hyperplasia (FNH) is the second most common benign liver tumor, primarily affecting women of childbearing age. It is typically asymptomatic and carries no risk of malignant transformation. While conservative management is usually preferred, diagnostic uncertainty or symptomatic cases may require intervention. Here, we present the case of a 23-year-old female with chronic periumbilical and lower abdominal pain. Extensive laboratory and imaging studies, including contrast-enhanced CT and MRI, revealed no abnormalities. Diagnostic laparoscopy was performed, which identified a superficially located, multilobulated mass on liver segment IVb. The patient opted for laparoscopic atypical liver segment resection, and histopathological analysis confirmed FNH. Postoperatively, the patient experienced symptom relief without complications. While most FNH cases are incidental and do not require intervention, this case highlights the diagnostic challenges and management of symptomatic lesions. Imaging, particularly contrast-enhanced MRI, is crucial to diagnosis, although biopsy may be necessary in atypical cases. Surgical resection is generally reserved for cases with diagnostic uncertainty, progressive lesion growth, or persistent symptoms. Minimally invasive options, such as transarterial chemoembolization or radiofrequency ablation, may serve as alternative treatment approaches. This case underscores the importance of individualized decision-making in the management of FNH. Although conservative management is typically the standard approach, surgical resection may be justified in symptomatic patients or when the diagnosis is unclear. Minimally invasive therapies offer promising alternatives in select cases.