Cavernous Hemangioma: A Potential Pitfall at Delayed 18F-FDG PET/CT Scan

Pitfalls in Positron Emission Tomography/Computed Tomography in the Thorax and Abdomen

Positron emission tomography/computed tomography (PET/CT) using [18F]-fluoro-2-deoxy-D-glucose (FDG) has become the mainstay imaging modality for evaluating oncology patients with certain cancers. The most common FDG PET/CT applications include staging/restaging, assessing response to therapy and detecting tumor recurrence. It is important to be aware of potential pitfalls and technical artifacts on PET/CT in the chest and abdomen to ensure accurate interpretation, avoid unnecessary intervention and optimize patient care.

PET/MRI evaluation of hepatobiliary tumors

Positron-emission tomography magnetic resonance imaging (PET/MRI) has emerged as a powerful hybrid molecular imaging technique in clinical practice, overcoming initial technical challenges to provide comprehensive anatomic and metabolic information. This advanced modality combines the superior soft tissue contrast of MRI with the metabolic insights of PET, offering advantages in hepatobiliary imaging, including improved detection of small liver metastases and reduced radiation exposure. The evolution of PET/MRI technology has been marked by significant advancements, such as the development of MRI-compatible PET detectors and sophisticated motion compensation techniques. These innovations have enhanced image quality and co-registration accuracy, crucial for hepatobiliary imaging. The integration of time-of-flight capability and silicon photomultipliers has further improved spatial resolution and sensitivity. PET/MRI protocols for liver imaging typically involve a whole-body scan followed by a targeted liver examination, utilizing radiotracers like FDG and DOTATATE. This approach allows for comprehensive staging and detailed liver assessment in a single session, potentially altering management decisions in up to 30% of patients with intrahepatic cholangiocarcinoma. While PET/MRI excels in characterizing various hepatobiliary lesions, including hepatocellular carcinoma and cholangiocarcinoma, challenges remain in differentiating certain benign entities like small hemangiomas from metastases. Ongoing research and clinical experience continue to refine the role of PET/MRI in hepatobiliary imaging, promising improved diagnostic accuracy and patient care.

Hepatic Cavernous Hemangioma Mimicking Malignancy on 18 F-FDG PET/CT Imaging

ABSTRACT

A 65-year-old woman was referred to our hospital because of a liver lesion revealed by ultrasound and CT in an outside institution. 18 F-FDG PET/CT images revealed an FDG-avid lesion in the left lateral lobe of the liver. Malignancy cannot be excluded. A subsequent resection was performed to remove the lesion. Postoperative pathology was hepatic cavernous hemangioma. This case suggests that PET/CT findings of FDG-avid hepatic cavernous hemangioma could mimic malignancy.

Jejunal Cavernous Hemangioma Mimicking Malignancy With Increased Activity on 18 F-FDG PET/CT

ABSTRACT

A 50-year-old woman underwent 18 F-FDG PET/CT to evaluate possible abdominal malignancy, which was revealed by CT. The images showed a large cystic-solid lesion with peripherally increased FDG activity in the left mid-abdomen. Histopathology of the excised lesion confirmed a jejunal cavernous hemangioma. We reported a rare case of jejunal cavernous hemangioma with FDG accumulation on PET/CT, mimicking malignancy.

Dual-Time-Point 18 F-FDG PET/CT for Differentiating a Chest Wall Hemangioma From a Malignant Metastasis

ABSTRACT

Dual-time-point 18 F-flluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) can be used to differentiate benign vascular tumors from other malignant growths. We present the case of a 70-year-old woman with a history of cervical carcinoma who was referred for PET/CT to examine a left chest wall tumor noted on CT, which involved the adjacent rib and pleura, thus raising the suspicion of metastasis. The chest wall tumor demonstrated moderate FDG uptake and further decreased uptake at the delayed-phase scanning, corresponding to biodistribution of FDG in the blood pool. These findings indicated a benign hemangioma rather than a metastasis.