Comparison of computed tomography response criteria after chemoembolization of hepatic carcinoma in dogs

The objective of this study was to evaluate unidimensional (mm), bidimensional (mm2) or tridimensional (mL) CT tumor measurements for ability to discriminate changes in lesion size and predict survival in dogs with nonresectable hepatic carcinoma (HC) treated with drug-eluting bead transarterial-chemoembolization (DEB-TACE) and to compare CT response via RECIST 1.1 (mm), WHO (mm2), ellipsoid and spherical volume (mL), and percent necrosis, for their ability to differentiate treatment responders. This was a prospective, single-arm clinical trial. DEB-TACE was performed to varying levels of blood flow stasis in 16 client-owned dogs with nonresectable HC. CT imaging responses were assessed and compared to MST. Results revealed that initial, follow-up, or changes in unidimensional, bidimensional, or tridimensional tumor measurements were not associated with survival. Larger bidimensional and tridimensional tumor measurements/body weight on initial and follow-up CT were significantly associated with a shorter MST (Bidimensional [p=0.04, 0.016] and tridimensional [p=0.025, 0.015], respectively). A higher percent necrosis on initial CT was significantly associated with shorter MST (p=0.038). Ellipsoid volumetric criteria detected treatment response most frequently, however response classification was not associated with MST. CT bidimensional and tridimensional tumor measurements/body weight prior to and following DEB-TACE may help to predict MST for dogs undergoing DEB-TACE for HC.