Radiation-induced liver disease as a mimic of liver metastases at serial PET/CT during neoadjuvant chemoradiation of distal esophageal cancer

Abstract

Purpose To determine the frequency and appearance of radiation-induced liver disease on PET/CT in patients undergoing serial imaging during neoadjuvant chemoradiation of distal esophageal cancer. Materials and Methods In this IRB-approved, HIPAA–compliant retrospective analysis, we identified 112 patients with distal esophageal cancer treated by neoadjuvant chemoradiation who had serial PET/CT imaging available for review. Two readers reviewed all studies in consensus and recorded those cases where new foci of visually detectable increased FDG avidity appeared in the liver during therapy. The etiology of such foci was determined from corresponding findings at CT or MRI, by hepatic biopsy during surgery, by characteristic evolution on post-operative imaging, or by a combination of these methods. Results New foci of FDG avidity developed in the liver during neoadjuvant therapy in 10 of 112 (9%) patients, of whom 9 (8%) were determined to have radiation-induced liver disease based on further imaging and/or biopsy and one of whom had developed interval metastatic disease based on biopsy. In the cases of radiation-induced liver disease, the abnormal foci were found only in the caudate and left hepatic lobes, near the primary tumor, while the patient who developed interval metastatic disease had involvement of the inferior right hepatic lobe, remote from the radiation therapy field. Conclusion New foci of increased FDG avidity are commonly seen in the caudate and left hepatic lobes of the liver during neoadjuvant chemoradiation of distal esophageal cancer, and these findings generally reflect radiation-induced liver disease rather than metastatic disease.

Prediction and diagnosis of interval metastasis after neoadjuvant chemoradiotherapy for oesophageal cancer using 18F-FDG PET/CT

“…As discussed, the false positive rate of 6% during 18 F-FDG PET/CT restaging was substantial, with the lungs and liver as the most frequent affected sites. This confirms previous findings in literature, with reported false positive rates ranging between 0% and 10% [ 6 , 36 ] and liver and lung as the most commonly affected sites [ 29 , 37 ]. This is likely caused by radiation-induced disease that may falsely indicate disease progression (Figs.…”

“…This confirms previous findings in literature, with reported false positive rates ranging between 0% and 10% [6, 36] and liver and lung as the most commonly affected sites [29, 37]. This is likely caused by radiation-induced disease that may falsely indicate disease progression (Figs.…”

“…2 and 3). Previous studies evaluating new FDG-avid hepatic lesions within the presumed radiation field of patients with oesophageal cancer demonstrated that these lesions generally reflect radiation-induced liver disease rather than metastatic disease [37–39]. Evaluation of radiation fields may, therefore, aid in the assessment of restaging 18 F-FDG PET/CT scans and further clinical decision-making [37].…”

Fever of Undetermined Origin During Neoadjuvant Chemoradiotherapy of Gastroesophageal Junction Adenocarcinoma Due to Radiation-induced Liver Disease

“…A retrospective observational study previously reported that 10 of the 112 patients developed new foci of fluorodeoxyglucose avidity on PET scan of the liver during neoadjuvant chemoradiotherapy of distal esophagus, of whom nine patients were diagnosed with radiation necrosis [14]. However, prolonged fever in this setting has not been previously reported.…”

Radiation-Induced Liver Injury Mimicking Metastatic Disease in a Patient With Esophageal Cancer

“…Location of the new FDG uptake in the left lobe and caudate lobe was predictive of radiation-induced liver injury, whereas the sole metastases in this cohort developed in a site distant from the radiation field. 12 Increased water content is found in irradiated liver parenchyma causing characteristic MRI findings including hypointense signal intensity on T1-weighted images and hyperintense signal intensity on T2-weighted images. 9 Eccles et al 13 have reported increased ADC of irradiated normal liver parenchyma in the first month after radiation therapy.…”