Case 50
Presentation:
69-year-old male admitted to the hospital for critical limb ischemia of the left leg. He was found to have incidental liver lesions.
CT scans demonstrated lytic lesions of the skull, bone scan showed uptake in the left 10th rib suspicious for metastases CT findings of the liver lesions was indeterminate though MRI of liver was in favor hemangiomas, referred for further assessment of liver lesions.
Fig-1: Tc99m RBC scan; static images acquired right after dynamic imaging
Findings: Subtle uptake overlying the liver parenchyma. Blood pool activity and uptake in the spleen are seen as expected.
A delayed SPECT-CT imaging was acquired (Fig-2 and 3).
Fig-2
Fig-3
Fig-2 & 3. The delayed SPECT-CT images showed solid uptake in the lesion in the right liver lobe (Fig-2) and a peripheral uptake with photopenia in the center (Fig-3) which finally showed a solid uptake.
Diagnosis:
Liver hemangiomas
Discussion:
Hepatic haemangiomas are benign, non-neoplastic, hypervascular lesions of the liver, typically classified as slow-flow venous malformations. While the majority of haemangiomas present with typical characteristics common in the general population, "atypical" haemangiomas are less frequent and include subtypes such as giant hemangiomas, hemangiomatosis, and pedunculated hemangiomas.
Other forms of haemangiomas include cavernous hemangioma, capillary hemangioma (also known as flash-filling or rapidly-filling hemangioma), and sclerosing hemangioma, which may also be referred to as thrombosed or hyalinized hemangioma.
Technetium-99m-labeled red blood cell (Tc-99m RBC) scintigraphy is a non-invasive diagnostic technique that offers high specificity in detecting hepatic haemangiomas. On Tc-99m RBC imaging, these lesions exhibit a distinctive mismatch between perfusion and blood pool, with reduced perfusion in the early dynamic phases followed by a gradual increase in radiotracer uptake during the blood pool phase. Initially, the lesion may appear "cold" or less active, but typically demonstrates intense activity within 1–2 hours after Tc-99m injection.
The sensitivity of this imaging method depends on lesion size: it is 17–20% for lesions under 1 cm, increases to 65–80% for lesions between 1 and 2 cm, and approaches nearly 100% for lesions larger than 2 cm in diameter. The specificity of Tc-99m RBC scintigraphy, especially when enhanced with Single Photon Emission Computed Tomography (SPECT), remains 100% across all lesion sizes.
References:
1. Vásquez Montoya JD, Molinares B, Vásquez Trespalacios EM, García V, Pérez Cadavid JC. Atypical hepatic haemangiomas. BJR Case Rep. 2017 Nov 1;4(1):20170029. doi: 10.1259/bjrcr.20170029.
2. Kacała A, Dorochowicz M, Matus I, Puła M, Korbecki A, Sobański M, Jacków-Nowicka J, Patrzałek D, Janczak D, Guziński M. Hepatic Hemangioma: Review of Imaging and Therapeutic Strategies. Medicina (Kaunas). 2024 Mar 8;60(3):449. doi: 10.3390/medicina60030449.
3. Nakanuma Y. Non-neoplastic nodular lesions in the liver. Pathol. Int. 1995;45:703–714. doi: 10.1111/j.1440-1827.1995.tb03386.x.