Shrinking hemangiomas amid advancing cirrhosis: A report of 2 cases.

Introduction
Hepatic hemangiomas are the most common benign vascular tumors of the liver and are often identified incidentally during imaging performed for unrelated clinical indications. In non-cirrhotic livers, these lesions typically exhibit classic imaging features, including hypo intensity on T1-weighted MRI, marked hyperintensity on T-2 weighted MRI, and peripheral nodular enhancement with progressive centripetal fill-in on contrast-enhanced imaging. These lesions are often found on repeat imaging to be stable or growing slowly [1,2].
In patients with cirrhosis, however, hemangiomas behave atypically. Studies suggest that hemangiomas can shrink due to the background fibrotic changes and altered hepatic vasculature that accompany cirrhosis [3]. This reduction in size does not indicate true lesion regression but rather reflects a deterioration of the background hepatic parenchyma. Additionally, hemangiomas in cirrhotic livers may lose typical imaging characteristics, complicating their differentiation from malignant lesions such as hepatocellular carcinoma or intrahepatic cholangiocarcinoma [4].
We present 2 cases of shrinking hepatic hemangiomas in the setting of progressive cirrhosis, illustrating the dynamic imaging evolution of these lesions. These cases highlight the evolving imaging appearance of hemangiomas in fibrotic livers and the importance of accurate radiologic interpretation in cirrhotic patients undergoing routine surveillance for hepatocellular carcinoma (HCC).

Case reports

Case 1
A 54-year-old female patient with liver cirrhosis secondary to untreated hepatitis C underwent MRI of the abdomen for HCC screening. Imaging revealed hepatic steatosis, mild heterogeneity of hepatic parenchyma, and mild surface nodularity. There was a right hepatic lobe lesion consistent with a hemangioma with a volume of 10.6 cubic centimeters (cc) and no suspicious findings. (Figs. 1A and B) 1 year later, a follow-up MRI showed the hemangioma had decreased to 6.4 cc (Fig. 1C and D). The background parenchyma displayed increased nodularity, caudate hypertrophy, and increased parenchymal heterogeneity. No suspicious focal lesions were seen in the repeat imaging either. Model for End Stage Liver Disease (MELD) sodium (Na) score was 11 at both instances, however no worsening signs of decompensated cirrhosis in the interim. Fig. 1 demonstrates a reduction in the size of the lesion with the advancement of the imaging features of cirrhosis.

Case 2
In another case, a 69-year-old male patient with cirrhosis due to alcohol use had an MRI ten years prior to evaluate a CT-detected liver lesion. The scan confirmed an 11.4 cc hemangioma in the right hepatic lobe. (Figs. 2A-C). A more recent MRI for HCC screening showed that the hemangioma had decreased to 2.9 cc (Figs. 2D-F). At the time of this second MRI 2 years later, the patient also had worsening clinical symptoms, such as peripheral edema. The MRI also demonstrated greater cirrhotic morphology of the liver, including greater surface nodularity, and portal hypertension. MELD Na score dropped from12 points to 8 points during the interval. Fig. 2 similarly demonstrates a reduction in size of the hemangioma in the context of a decreasing MELD score with slightly worsened imaging features of liver cirrhosis.

Discussion
Hemangiomas in cirrhotic livers often decrease in size, become more fibrotic, and may lose their typical enhancement pattern, complicating radiologic diagnosis. This process is thought to result from the underlying fibrotic changes and alteration of hepatic vasculature implicit in the disease. Cirrhosis has been found to result in the alteration of natural hepatic perfusion through various mechanisms, including development of shunt vessels, dilated sinusoids, and altered microvascular flow, producing uneven perfusion and areas with limited blood flow [5,6]. One proposed for the shrinkage mechanism is the narrowing of vascular pools due to fibrotic distortion, resulting in a vascular redistribution process that only leaves hyperdynamic portions of the hemangiomas visible [3]. Additionally, fibrosis may physically compress the hemangioma and collapse its vascular pools, resulting in a smaller appearance [3]. This hypothesis is supported by 3D vascular casting in rat models which demonstrates that advancing cirrhosis may cause a collapse in hepatic vasculature, particularly near the liver’s surface [7].
In a study of 17 cirrhotic patients with 21 hemangiomas, 7 lesions decreased in size and 5 displayed capsular retraction, highlighting that hemangiomas can shrink in size alongside an overall reduction in liver volume. Several hemangiomas lost typical imaging features such as nodular peripheral enhancement and isoattenuation to blood. In 1 case, a previously classic hemangioma evolved into a nonmenacing fibrotic scar, highlighting the potential for dramatic imaging transformation in cirrhosis [8].
MRI signal characteristics and enhancement patterns of hemangiomas may be altered in cirrhotic livers, sometimes mimicking malignant lesions, such as small HCCs. Nearly 24% of hemangiomas in cirrhotic livers had atypical enhancement patterns (e.g., heterogenous enhancement, lack of complete fill-in, and reduced T2 signal), compared to 5% in non-cirrhotic livers. Atypical hemangiomas usually deviate from classical imaging patterns, making them more difficult to distinguish from malignancies, such as small HCCs. The diagnostic confidence of radiologists decreased significantly when interpreting hemangiomas in fibrotic livers due to overlapping imaging features with malignancy [4]. MRI with hepatobiliary contrast agents such as gadoxetic acid improves detection of HCC lesions less than 2 cm and helps differentiate HCC from hemangiomas [9]. Features consistent with hemangiomas on gadoxetic acid-enhanced MRI include bright signal on T2, high apparent diffusion coefficient value, and equal signal intensity to the portal vein [9]. Furthermore, ultrasound evaluation in cirrhotic patients can be utilized to guide the differential diagnosis of hepatic hemangiomas.
The American College of Gastroenterology recommends ongoing surveillance of focal liver lesions in cirrhotic patients due to elevated risk of malignancy [1]. Accordingly, radiologists should exercise caution when evaluating hemangiomas in cirrhotic livers, particularly changes in size, signal intensity, or enhancement patterns occur. Our case illustrates these challenges, emphasizing the importance of recognizing atypical hemangioma behavior in cirrhotic patients undergoing routine HCC surveillance.

Conclusions
Although hepatic hemangiomas are common and typically stable, their imaging appearance may change significantly as the liver becomes progressively fibrotic. These transformations may appear atypical or even regressive but often reflect the altered baseline physiology of the cirrhotic liver rather than true lesion evolution. This case report underscores the importance of recognizing such patterns to avoid misinterpretation of benign lesions as malignant during routine surveillance in patients with cirrhosis.

Authors contributions
The authors declare that this is their original work, and they all approve the content of this manuscript. They confirm that this manuscript has not been published previously, in any language, in whole or in part, and is not currently under consideration elsewhere.

Ethical clearance
This project did not involve any research and no ethical clearance was required.

Patient consent
A written informed consent was obtained from the patient for the publication of this case report.