Imaging Evaluation after Stereotactic Body Radiotherapy for Hepatocellular Carcinoma: Prognostic Value of Radiological Changes

Full Article

KY Man, YS Luk, ALY Law, WKW Leung

Hong Kong J Radiol 2019;22:160-71

Objective: To evaluate the computed tomography and magnetic resonance imaging features of tumour response and predictive factors of time to progression and survival after stereotactic body radiotherapy for hepatocellular carcinoma.
Methods: Consecutive patients with hepatocellular carcinoma who were treated by stereotactic body radiotherapy between June 2006 and September 2016 were included in this retrospective study. Clinical and radiological data obtained using computed tomography or magnetic resonance imaging were examined. The response rate, in-field local control, time to progression, overall survival and prognostic factors were evaluated. Treatment response was classified according to modified Response Evaluation Criteria in Solid Tumors.
Results: In total, 73 patients were included. The complete response, partial response, stable disease, and disease progression rates were 41.1%, 20.5%, 27.4% and 11% respectively. The in-field local control rates at 1 year and 2 years were 95.9% and 92.1%, respectively. The median follow-up time was 19 months and the median overall survival was 20 months. T1-weighted or T2-weighted signal intensities, pattern of lipiodol stain, complete thin rim enhancement and focal liver reaction in post-treatment images were shown to be independent predictors for progression or overall survival.
Conclusion: Imaging evaluation of tumour response is important. Recognising and interpreting the radiological features of tumour response (both tumour and juxtaposed non-tumourous hepatic parenchyma) is essential in making an accurate assessment of treatment response. Accurate imaging evaluation may also help predict survival.


Author affiliation(s):
KY Man, YS Luk, WKW Leung: Department of Radiology, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong
ALY Law: Department of Clinical Oncology, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong