Use of the Term "Atypical Hepatic Hemangioma" in Radiology Reports: An Analysis of Diagnostic Precision

Background/Objectives: Hepatic hemangiomas are the most common benign liver tumors, typically diagnosed confidently by their classic imaging features. However, a subset displays atypical characteristics that complicate diagnosis. We hypothesized that the term "atypical hemangioma" is used inconsistently and may contribute to both over-investigation of benign lesions and missed malignancies. Accordingly, this study aimed to assess the implications of the use of this term in radiology reports. Methods: This retrospective multicenter study reviewed 327 hepatic lesions labeled as atypical hemangiomas in radiology reports from two tertiary hospitals between 2013 and 2023. Two abdominal radiologists independently assessed imaging characteristics. Final diagnoses were based on imaging stability, histopathology or clinical follow-up. Results: Of the 327 lesions, 305 (93.3%) were benign and 22 (6.7%) malignant. Among the malignant lesions, 11 (50%) had no recommendations for further workup, and 10 (45%) did not mention malignancy in the differential diagnosis. Malignant lesions were significantly larger (mean size: 49.5-50.8 mm vs. 28.1-29.1 mm; p < 0.001), more likely to have ill-defined margins (50-54.5% vs. 17.9-18.1%; p ≤ 0.001), early heterogeneous enhancement (46.2% vs. ~9.5%; p < 0.001), and restricted diffusion (75-100% vs. 7.8-17.6%; p < 0.001). Among the benign lesions, 128 (42%) could have been confidently diagnosed at baseline, yet 62 of these lesions underwent unnecessary additional workup. Conclusions: The term "atypical hemangioma" is inconsistently used and associated with both delayed cancer diagnosis and excessive workup of benign lesions. Standardized terminology and risk-adapted strategies may improve diagnostic accuracy, optimize management, and minimize patient harm. Prospective validation of standardized imaging criteria is warranted.