735P - Radiographic parameters in predicting outcome of patients with hepatocellular carcinoma (HCC) treated with yttrium-90 microsphere radioembolization...
|Date||30 September 2012|
|Event||ESMO Congress 2012|
|Session||Poster presentation II|
|Topics|| Hepatobiliary Cancers
M. Salem1, N. Jain2, S. Taylor2, G. Dyson2, J. Beebe-Dimmer2, M. Choi2, A.F. Shields2, J.J. Critchfield2, P.A. Philip2
The predictive role of radiographic parameters in HCC pts undergoing transarterial hepatic selective internal radiotherapy (SIRT) is not fully characterized. The objective of this retrospective study was to determine whether radiographic parameters at baseline and/or radiographic changes following SIRT predict outcome in HCC pts treated with Yttrium-90 glass microsphere radioembolization.Methods
Baseline and post-SIRT CT images (median of 6 weeks) were analyzed. Various features such as tumor size; attenuation; margins; enhancement; and amount of tumor necrosis were examined. Selected radiographic parameters were evaluated & correlated with PFS & OS. Objective response was assessed by RECIST 1.1 and Morphology, Attenuation, Size, and Structure (MASS) criteria (favorable (FR) vs. non favorable). Differences were analyzed using Wilcoxon Signed Rank Test and Fisher's Exact Test. Kaplan-Meier methods were used to estimate survival curves. Cox regression was used in uni- and multi- variable survival analysesResults
Twenty-four pts (79% M; median age 63 y) received a median radiation dose of 1.965 GBq. On post-SIRT CT, 65% of tumors had decreased longest diameter (median decrease 8%, p = 0.27); 64% had decreased attenuation (median decrease 18 HU, p = 0.067), and 45% demonstrated increased tumor necrosis (p < 0.001). RECIST-defined partial response was seen in 10% of pts, stable disease in 80% and 10% had disease progression. Median PFS and OS were 4.4 and 11.6 months, respectively. Of the 9 pts who were response evaluable by MASS criteria, FR was a predictor of PFS (p = 0.03) with median time to progression not being reached vs. 5.5 months for the non-FR group. In univariate analyses, well-defined tumor margins, lower hepato-pulmonary shunt fraction and peripheral hypervascularity were associated with prolonged PFS. On multivariate analysis, tumor margins and shunt fraction were correlated with PFS whereas extrahepatic disease and liver cirrhosis were independent predictors of OS.Conclusions
In pts with HCC, pre-treatment tumor margins and shunt fraction may be developed as biomarkers to identify pts who are unlikely to benefit from SIRT. In addition, response evaluation by MASS criteria may provide better and earlier determination of lack of benefit from SIRT and the need for further therapy.Disclosure
All authors have declared no conflicts of interest.