Analysis of Computed Tomography Derived Maps for Determining Changes of the Liver Volume After Exposure to Radiotherapy

Radiotherapy plays a central role in the management of primary and metastatic tumors involving the liver or adjacent anatomical regions. Despite advances in radiation delivery techniques, the liver remains a radiosensitive organ, and radiation-induced liver injury continues to be a clinically significant concern. Quantitative assessment of liver volume changes may provide valuable insight into hepatic response and tolerance to radiation exposure.

This study is designed to analyze computed tomography (CT)-derived liver volume maps to assess changes in liver volume following radiotherapy. CT images acquired as part of standard clinical practice will be used to generate volumetric measurements of the liver at baseline and during post-treatment follow-up. Advanced image analysis techniques will be applied to evaluate spatial and global liver volume changes.

The study is observational in nature and does not involve any investigational drugs or devices. All imaging data will be obtained from routine clinical workflows without modification to standard patient care. Demographic, clinical, and treatment-related parameters may be correlated with observed liver volume changes to explore potential associations.

The results of this study are expected to enhance understanding of radiation-related hepatic effects and support optimization of radiotherapy planning strategies. Improved knowledge of liver volume dynamics may contribute to better prediction of treatment-related toxicity and support individualized patient management in future clinical practice.

• Inclusion criteria:

• Adults aged 18 years or older.
• Received radiation therapy (RT) involving the liver (e.g., SBRT, IMRT). The study involves patients in whom the liver was exposed to radiotherapy, either as a direct target (in hepatic-directed treatments as in HCC or liver metastasis) or indirectly as an organ-at-risk (OAR) during irradiation of nearby anatomical regions (as lower lung, gastric, or abdominal sites) where the liver was partially included within the radiation field.

The analysis aims to evaluate radiation-induced volumetric changes regardless of whether the liver was the primary target or secondarily affected.

• Availability of paired pre- and post-RT CT scans of sufficient quality.
• 3D dose distribution data from the RT treatment plan.
• Clinical follow-up data, including liver function tests and toxicity records.
• No evidence of major anatomical changes between scans unrelated to RT (e.g., surgery).
• Exclusion criteria:

• Patients with a history of major liver surgery (e.g., resection or transplant) between the pre- and post-RT scans.
• Presence of severe motion artifacts or poor-quality CT scans that hinder accurate image analysis.
• Incomplete or missing 3D radiation dose distribution data.
• Lack of sufficient clinical follow-up information (e.g., liver function tests, toxicity outcomes).
• Concurrent systemic therapies (e.g., chemotherapy or immunotherapy) during the imaging interval that may confound liver volume changes, unless controlled for in analysis.
• Pre-existing liver conditions that could independently alter liver volume (e.g., cirrhosis, advanced hepatic steatosis) if not accounted for.
• Patients under 18 years of age.