Radiation-induced liver disease (RILD), also referred to as radiation hepatitis, represents the toxic effect of radiation therapy on normal hepatocytes.
This article will discuss liver toxicity appearances after external beam radiotherapy techniques. Please refer to the dedicated article on selective internal radiation therapy (SIRT) for further details on this matter.
Liver injury tends to be more common in those patients with radiation doses greater than 30 Gy or when the whole-liver is irradiated 3. It is usually seen as a result of therapy to adjacent organs, such as pancreatic carcinoma, gallbladder carcinoma, retroperitoneal lymphoma, pleural mesothelioma, distal esophageal and other lower thoracic malignancies.
In most cases, where the liver is only focally irradiated, patients are asymptomatic and the hepatocytes injury is depicted on abnormal liver function tests. When there is a more severe acute hepatitis, patients may complain of right upper quadrant discomfort 3.
In the acute phase, the radiation injury typically manifests as sharply demarcated parenchymal areas of low attenuation that correlate to the radiation ports 2,3. They characteristically do not respect anatomical boundaries, eg. involving more than one segment passing through the hepatic veins. In equivocal cases, correlation with the conformal radiotherapy dose distributions maps can be helpful 3.
If the liver is steatotic, the injured parenchyma may present with elevated attenuation compared to the background liver 2.
In the late phase of cases of severe toxicity, sequela with focal liver atrophy and capsular retraction may be seen 2.
The demarcated areas have increased T2 signal in keeping with acute inflammation 2,3.
The liver areas of low attenuation will match with high FDG avidity on PET/CT in the acute phase 2.
- liver metastasis: do not fit within the radiation portal
- 1. Katherine E. Maturen, Mary U. Feng, Ashish P. Wasnik, Shadi F. Azar, Henry D. Appelman, Isaac R. Francis, Joel F. Platt. Imaging Effects of Radiation Therapy in the Abdomen and Pelvis: Evaluating “Innocent Bystander” Tissues. (2013) RadioGraphics. 33 (2): 599-619. doi:10.1148/rg.332125119 - Pubmed
- 2. Marcelo F. Benveniste, Daniel Gomez, Brett W. Carter, Sonia L. Betancourt Cuellar, Girish S. Shroff, Ana Paula A. Benveniste, Erika G. Odisio, Edith M. Marom. Recognizing Radiation Therapy–related Complications in the Chest. (2019) RadioGraphics. 39 (2): 344-366. doi:10.1148/rg.2019180061 - Pubmed
- 3. Reginald F. Munden, Jeremy J. Erasmus, William R. Smythe, John E. Madewell, Kenneth M. Forster, Craig W. Stevens. Radiation Injury to the Liver After Intensity-Modulated Radiation Therapy in Patients with Mesothelioma: An Unusual CT Appearance. (2012) American Journal of Roentgenology. 184 (4): 1091-5. doi:10.2214/ajr.184.4.01841091 - Pubmed
Related Radiopaedia articles
external beam radiation therapy (EBRT)
- conventional (2D) radiation therapy
- 3D conformal radiation therapy
- intensity-modulated radiation therapy (IMRT)
- stereotactic radiosurgery
- electron therapy
- particle (hadronic) therapy
- sealed source radiation therapy (brachytherapy)
- unsealed source radiation therapy
- external beam radiation therapy (EBRT)
- complications related to radiation therapy
- acute radiation syndrome
- complications of cranial radiation therapy
- radiation-induced thyroid cancer
- radiation-induced neuritis
complications of thoracic radiation therapy
- soft tissues
- bony thoracic cage
- complications of abdominopelvic radiation therapy
- radiation-induced bone marrow signal changes - MRI