Intraprocedural C-arm dual-phase cone-beam CT: can it be used to predict short-term response to TACE with drug-eluting beads in patients with hepatocellular carcinoma?

PURPOSE: To investigate whether C-arm dual-phase cone-beam computed tomography (CT) performed during transcatheter arterial chemoembolization (TACE) with doxorubicin-eluting beads can help predict tumor response at 1-month follow-up in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This prospective study was compliant with HIPAA and approved by the institutional review board and animal care and use committee. Analysis was performed retrospectively on 50 targeted HCC lesions in 29 patients (16 men, 13 women; mean age, 61.9 years ± 10.7) treated with TACE with drug-eluting beads. Magnetic resonance (MR) imaging was performed at baseline and 1 month after TACE. Dual-phase cone-beam CT was performed before and after TACE. Tumor enhancement at dual-phase cone-beam CT in early arterial and delayed venous phases was assessed retrospectively with blinding to MR findings. Tumor response at MR imaging was assessed according to European Association for the Study of the Liver (EASL) guidelines. Two patients were excluded from analysis because dual-phase cone-beam CT scans were not interpretable. Logistic regression models for correlated data were used to compare changes in tumor enhancement between modalities. The radiation dose with dual-phase cone-beam CT was measured in one pig. RESULTS: At 1-month MR imaging follow-up, complete and/or partial tumor response was seen in 74% and 76% of lesions in the arterial and venous phases, respectively. Paired t tests used to compare images obtained before and after TACE showed a significant reduction in tumor enhancement with both modalities (P < .0001). The decrease in tumor enhancement seen with dual-phase cone-beam CT after TACE showed a linear correlation with MR findings. Estimated correlation coefficients were excellent for first (R = 0.89) and second (R = 0.82) phases. A significant relationship between tumor enhancement at cone-beam CT after TACE and complete and/or partial tumor response at MR imaging was found for arterial (odds ratio, 0.95; 95% confidence interval [CI]: 0.91, 0.99; P = .023) and venous (odds ratio, 0.96; 95% CI: 0.93, 0.99; P = .035) phases with the multivariate logistic regression model. Radiation dose for two dual-phase cone-beam CT scans was 3.08 mSv. CONCLUSION: Intraprocedural C-arm dual-phase cone-beam CT can be used immediately after TACE with doxorubicin-eluting beads to predict HCC tumor response at 1-month MR imaging follow-up.

Evaluating tumors in transcatheter arterial chemoembolization (TACE) using dual-phase cone-beam CT.

C-arm cone-beam computed tomography (CBCT) can be used to visualize tumor-feeding vessels and parenchymal staining during transcatheter arterial chemoembolization (TACE). To capture these two phases, all current commercially available CBCT systems necessitate two separate contrast-enhanced scans. In this feasibility study, we report initial results of novel software that enhanced our current CBCT system to capture these two phases using only one contrast injection. Novelty of this work is the addition of software that enabled the acquisition of two sequential, back-to-back CBCT scans (dual-phase CBCT, DPCBCT) so both tumor feeding vessels and parenchyma are captured using only one contrast injection. To illustrate our initial experience, DPCBCT was used for TACE treatments involving lipiodol, drug-eluting beads, and Yttrium-90 radioembolizing microspheres. For each case, the DPCBCT images were compared to pre-intervention contrast-enhanced MR/CT. DPCBCT is feasible for TACE treatments and the preliminary results show positive correlation with pre-intervention conventional CT and MR. In addition, the degree of embolization can be monitored. DPCBCT is a promising technology that provides comprehensive visualization of tumor-feeding vessels and parenchymal staining using a single injection of contrast. DPCBCT could potentially be used during TACE to verify catheter position and monitor the embolization effect.

Comparing the detectability of hepatocellular carcinoma by C-arm dual-phase cone-beam computed tomography during hepatic arteriography with conventional contrast-enhanced magnetic resonance imaging.

PURPOSE: To evaluate the sensitivity of dual-phase cone-beam computed tomography during hepatic arteriography (CBCTHA) for the detection of hepatocellular carcinoma (HCC) by comparing it with the diagnostic imaging "gold standard": contrast-enhanced magnetic resonance imaging (CE-MRI) of the liver. MATERIALS AND METHODS: Eighty-eight HCC lesions (mean diameter 3.9 ± 3.3 cm) in 20 patients (13 men, mean age 61.4 years [range 50 to 80]), who sequentially underwent baseline diagnostic liver CE-MRI and then underwent early arterial- and delayed portal venous-phase CBCTHA during drug eluting-bead transarterial chemoembolization, were evaluated. Dual-phase CBCTHA findings of each tumor in terms of conspicuity were compared with standard CE-MR images and classified into three grades: optimal, suboptimal, and nondiagnostic. RESULTS: Seventy-seven (mean diameter 4.2 ± 3.4 cm [range 0.9 to 15.9]) (93.9%) of 82 tumors were detected. Sensitivity of arterial-phase (71.9%) was lower than that of venous-phase CBCTHA (86.6%) for the detection of HCC lesions. Of the 82 tumors, 33 (40.2%) and 52 (63.4%), 26 (31.7%) and 19 (23.2%), and 23 (28%) and 11 (13.4%) nodules were classed as optimal, suboptimal, and nondiagnostic on arterial- and venous-phase CBCTHA images, respectively. Seventeen (73.9%) of the 23 tumors that were not visible on arterial phase were detected on venous phase. Six (54.5%) of the 11 tumors that were not visible on venous phase were detected on arterial phase. CONCLUSIONS: Dual-phase CBCTHA has sufficient image quality to detect the majority of HCC lesions compared with the imaging "gold standard": CE-MRI of the liver. Moreover, dual-phase CBCTHA is more useful and reliable than single-phasic imaging to depict HCC nodules.