Decrease in tumor enhancement on contrast-enhanced CT is associated with improved survival in patients with hepatocellular carcinoma treated with Sorafenib

Variability of HCC Tumor Diameter and Density Measurements on Dynamic Contrast-Enhanced Computed Tomography

PURPOSE

In cancers imaged using contrast-enhanced protocols, such as hepatocellular carcinoma (HCC), formal guidelines rely on measurements of lesion size (in mm) and radiographic density (in Hounsfield units [HU]) to evaluate response to treatment. However, the variability of these measurements across different contrast enhancement phases remains poorly understood. This limits the ability of clinicians to discern whether measurement changes are accurate.

METHODS

In this study, we investigated the variability of maximal lesion diameter and mean lesion density of HCC lesions on CT scans across four different contrast enhancement phases: non-contrast-enhanced phase (NCE), early arterial phase (E-AP), late arterial phase (L-AP), and portal venous phase (PVP). HCC lesions were independently segmented by two expert radiologists. For each pair of a lesion's scan timepoints, one was selected randomly as the baseline measurement and the other as the repeat measurement. Both absolute and relative differences in measurements were calculated, as were the coefficients of variance (CVs). Analysis was further stratified by both contrast enhancement phase and lesion diameter.

RESULTS

Lesion diameter was found to have a CV of 5.11% (95% CI: 4.20-6.01%). About a fifth of the measurement's relative changes were greater than 10%. Although there was no significant difference in diameter measurements across different phases, there was a significant negative correlation (R = -0.303, p-value = 0.030) between lesion diameter and percent difference in diameter measurement. Lesion density measurements varied significantly across all phases, with the greatest relative difference of 47% in the late arterial phase and a CV of 22.84% (21.48-24.20%). The overall CV for lesion density measurements was 26.19% (24.66-27.72%).

CONCLUSIONS

Changes in tumor diameter measurements within 10% may simply be due to variability, and lesion density is highly sensitive to contrast timing. This highlights the importance of paying attention to these two variables when evaluating tumor response in both clinical trials and practice.

Dual-Energy Computed Tomography-Based Iodine Concentration Estimation for Evaluating Choroidal Malignant Melanoma Response to Treatment: Optimization and Primary Validation

Contrast-enhanced imaging for choroidal malignant melanoma (CMM) is mostly limited to detecting metastatic tumors, possibly due to difficulties in fixing the eye position. We aimed to (1) validate the appropriateness of estimating iodine concentration based on dual-energy computed tomography (DECT) for CMM and optimize the calculation parameters for estimation, and (2) perform a primary clinical validation by assessing the ability of this technique to show changes in CMM after charged-particle radiation therapy. The accuracy of the optimized estimate (eIC_optimized) was compared to an estimate obtained by commercial software (eIC_commercial) by determining the difference from the ground truth. Then, eIC_optimized, tumor volume, and CT values (80 kVp, 140 kVp, and synthesized 120 kVp) were measured at pre-treatment and 3 months and 1.5−2 years after treatment. The difference from the ground truth was significantly smaller in eIC_optimized than in eIC_commercial (p < 0.01). Tumor volume, CT values, and eIC_optimized all decreased significantly at 1.5−2 years after treatment, but only eIC_commercial showed a significant reduction at 3 months after treatment (p < 0.01). eIC_optimized can quantify contrast enhancement in primary CMM lesions and has high sensitivity for detecting the response to charged-particle radiation therapy, making it potentially useful for treatment monitoring.

Combination therapy of sorafenib and drug-eluting bead transarterial chemoembolization for advanced hepatocellular carcinoma with and without hepatic arteriovenous shunt

BACKGROUND

To compare the efficacy and safety of combination therapy with sorafenib and drug-eluting bead transarterial chemoembolization (DEB-TACE) in advanced hepatocellular carcinoma (HCC) with or without hepatic arteriovenous shunt (HAVS).

METHODS

This retrospective, single-center study enrolled 59 advanced HCC patients treated with combination therapy, of whom 33 (55.9%) patients had HAVS. Tumor response according to the mRECIST criteria was evaluated based on the CT images 1 month after TACE, and changes in the arterial enhancement ratio (AER) of tumors and portal vein tumor thrombosis were also documented. Time-to-progression (TTP), overall survival (OS), and prognostic factors were analyzed. Safety was evaluated with the incidence of TACE-related complications within 6 weeks after TACE.

RESULTS

The tumor response between the two groups showed no significant difference in the objective response rate (69.2% in the group without HAVS vs 60.6% in the group with HAVS, p = 0.492) or disease control rate (92.3% vs 87.9%, p = 0.685). The two groups showed comparable TTP (4.23 vs 2.33 months, p = 0.235) and OS (12.77 vs 12.97 months, p = 0.910). A drop in the AER of tumors of more than 20% on post-TACE CT independently predicted better OS. With regard to safety, there was no significant difference between the two groups.

CONCLUSION

For advanced HCC, combination therapy had equal efficacy and safety in patients with HAVS compared to those without HAVS, indicating that DEB-TACE is an optional and effective treatment in these patients.