Peliosis Hepatis Simulating Metastatic Liver Disease on FDG PET/CT

Two Rare Benign Lesions on 18F-FDG PET/CT: Peliosis Hepatis and SANT

Peliosis hepatis (PH) and sclerosing angiomatoid nodular transformation of the spleen are uncommon benign lesions. Diagnosis can be difficult in some patients. Herein, we present the case of a 28-year-old woman referred with abdominal pain who had spleen lesions. 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography revealed multiple non-FDG avid lesions in the liver and hypermetabolic lesions in the spleen. In addition, abdominal magnetic resonance imaging was performed. Histopathology revealed sclerosing angiomatoid nodular transformation in the spleen and PH in the liver.

MRI of Peliosis Hepatis: A Case Series Presentation With a 2022 Systematic Literature Update

BACKGROUND

Peliosis hepatis (PH) is a rare benign condition, characterized by hepatic sinusoidal dilatation and blood-filled cystic cavities, often found incidentally, with still challenging diagnosis by imaging due to polymorphic appearance.

PURPOSE

Based on a retrospective analysis of our series (12 patients) and systematic literature review (1990-2022), to organize data about PH and identify features to improve characterization.

STUDY TYPE

Retrospective case series and systematic review.

POPULATION

Twelve patients (mean age 48 years, 55% female) with pathology-proven PH and 49 patients (mean age 52 years, 67% female) identified in 33 studies from the literature (1990-2022).

FIELD STRENGTH/SEQUENCE

1,5-T; T1-weighted (T1W), T2-weighted (T2W), diffusion-weighted (DW), contrast-enhanced (CE) T1W imaging.

ASSESSMENT

We compared our series and literature data in terms of demographic (gender/age/ethnicity), clinical characteristics (symptoms/physical examination/liver test), associated conditions (malignancies/infectious/hematologic/genetic or chronic disorders/drugs or toxic exposure) percentage. On magnetic resonance imaging lesion numbers/shape/mean maximum diameter/location/mass effect/signal intensity were compared. PH pathological type/proposed imaging diagnosis/patient follow-up were also considered.

STATISTICAL TESTS

Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Case Reports/Series quality assessment. Intraclass correlation and Cohen's kappa coefficients for levels of inter/intrareader agreement in our experience.

RESULTS

Patients were mainly asymptomatic (92% vs. 70% in our study and literature) with associated conditions (83% vs. 80%). Lesions showed homogeneous T1W-hypointensity (58% vs. 65%) and T2W-hyperintensity (58% vs. 66%). Heterogeneous nonspecific (25% vs. 51%), centrifugal (34% vs. 8%), or rim-like centripetal (25% vs. 23%) patterns of enhancement were most frequent, with hypointensity on the hepatobiliary phase (HBP), without restricted diffusivity. Good inter- and intrareader agreement was observed in our experience. Concerning JBI Checklist, 19 out of 31 case reports met at least 7 out of 8 criteria, whereas 2 case series fulfilled 5 and 6 out of 10 items respectively.

DATA CONCLUSION

A homogeneous, not well-demarcated T1W-hypointense and T2W-hyperintense mass, with heterogeneous nonspecific or rim-like centripetal or centrifugal pattern of enhancement, and hypointensity on HBP, may be helpful for PH diagnosis. Among associated conditions, malignancies and drug exposures were the most frequent.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 2.

FDG-PET/CT: novel method for viability assessment of livers perfused ex vivo

PURPOSE

Ex vivo liver machine perfusion is a promising option to rescue marginal liver grafts mitigating the donated organ shortage. Recently, a novel liver perfusion machine that can keep injured liver grafts alive for 1 week ex vivo was developed and reported in Nature Biotechnology. However, liver viability assessment ex vivo is an unsolved issue and the value of 18F-fluorodeoxyglucose (FDG)-PET/CT for such purpose was explored.

MATERIALS AND METHODS

Discarded two human and six porcine liver grafts underwent FDG-PET/CT for viability assessment after 1 week of ex vivo perfusion. PET parameters [standardized uptake value (SUV)max, SUVmean, SUVpeak and total lesion glycolysis] were compared between hepatic lobes and between porcine and human livers. The prevalence of FDG-negative organ parts was recorded. The estimated effective radiation dose for PET/CT was calculated.

RESULTS

All organs were viable with essentially homogeneous FDG uptake. Of note, viability was preserved in contact areas disclosing the absence of pressure necrosis. Four porcine and two human organs had small superficial FDG-negative areas confirmed as biopsy sites. Total lesion glycolysis was significantly higher in the right hepatic lobe (P = 0.012), while there was no significant difference of SUVmax, SUVmean and SUVpeak between hepatic lobes. There was no significant difference in FDG uptake parameters between porcine and human organs. The estimated effective radiation dose was 1.99 ± 1.67 mSv per organ.

CONCLUSION

This study demonstrates the feasibility of FDG-PET/CT for viability assessment of ex vivo perfused liver grafts after 1 week.

Ultrasound findings in peliosis hepatis

Purpose

The aim of this study was to retrospectively evaluate contrast-enhanced ultrasound (CEUS) findings in patients with peliosis hepatis (PH).

Methods

A retrospective analysis was conducted of CEUS features in 24 patients with histopathologically confirmed PH (11 men and 13 women; mean age, 32.4±7.1 years; range, 28 to 41 years). All lesions were histologically proven, either by core needle biopsy (n=10) or by hepatic surgery (n=14).

Results

The mean size was 36.8±12.4 mm (range, 10 to 80 mm). On B-mode ultrasonography (BMUS), all PH lesions were heterogeneously hypoechoic, with well-defined margins but irregular shapes. No mass effect was observed. During the arterial phase of CEUS, all lesions displayed mild heterogeneous hyperenhancement (83.3%, 20/24) or isoenhancement (16.7%, 4/24). Furthermore, 87.5% of the PH lesions showed mild washout after 1 minute in the portal venous phase (30-120 seconds) and mild washout in the late phase (>120 seconds).

Conclusion

The lack of a mass effect on BMUS, mild heterogeneous arterial hyperenhancement, and washout in the very late portal venous phase (after 1 minute) on CEUS are characteristic of PH. Although it is a histological diagnosis, PH should be considered in the differential diagnosis when the clinical context does not favor a malignancy or infection.

A rare case of peliosis hepatis in primary immune deficiency

Peliosis hepatis is a rare condition characterized by blackish-blue blood-filled cavities in hepatic parenchyma caused by dilatation of hepatic sinusoids. Peliosis hepatis has been described in secondary immunodeficiencies and certain medications. We present the first case of peliosis hepatis in a patient with a primary immunodeficiency, common variable immunodeficiency. A 44-year-old African-American male presented with gastrointestinal bleeding and elevated liver function tests. His medical history included common variable immunodeficiency and chronic kidney disease. The patient had jaundice, regenerative nodules on liver pathology, and low immunoglobulin levels. A magnetic resonance imaging of the abdomen with contrast revealed a cirrhotic liver, a 5 × 3 cm lesion, and poorly defined nodules which had decreased enhancement. A computed tomography-guided liver biopsy revealed peliosis hepatis, focal nodular hyperplasia, and fibrosis. No other etiology of his liver disease was found. The etiology of peliosis hepatis in patients with primary immunodeficiencies remains unclear. Additional studies are needed to understand the underlying mechanisms.

Liver haematoma as a presentation of peliosis hepatis

Peliosis hepatis (PH) is an uncommon, benign hepatic vascular condition involving liver lesions consisting of dilated sinusoidal spaces that ultimately lead to numerous blood-filled cavities within the liver parenchyma. We detail the case of a 62-year-old woman who presented with a large hepatic haematoma resulting from intracystic haemorrhage. She was subsequently diagnosed with PH via arteriogram. Her symptoms were successfully treated surgically with open fenestration. Patient's postoperative course was unremarkable, with no recurrence of symptoms to date.