Analysis of Tumor Burden as a Biomarker for Patient Survival with Neuroendocrine Tumor Liver Metastases Undergoing Intra-Arterial Therapies: A Single-Center Retrospective Analysis.

PURPOSE: To assess the value of quantitative analysis of tumor burden on baseline MRI for prediction of survival in patients with neuroendocrine tumor liver metastases (NELM) undergoing intra-arterial therapies. MATERIALS AND METHODS: This retrospective single-center analysis included 122 patients with NELM who received conventional (n = 74) or drug-eluting beads, (n = 20) chemoembolization and radioembolization (n = 28) from 2000 to 2014. Overall tumor diameter (1D) and area (2D) of up to 3 largest liver lesions were measured on baseline arterially contrast enhanced MR images. Three-dimensional quantitative analysis was performed using the qEASL tool (IntelliSpace Portal Version 8, Philips) to calculate enhancing tumor burden (the ratio between enhancing tumor volume and total liver volume). Based on Q-statistics, patients were stratified into low tumor burden (TB) or high TB. RESULTS: The survival curves were significantly separated between low TB and high TB groups for 1D (p < 0.001), 2D (p < 0.001) and enhancing TB (p = 0.008) measurements, with, respectively, 2.7, 2.6 and 2.2 times longer median overall survival (MOS) in the low TB group (p < 0.001, p < 0.001 and p = 0.008). Multivariate analysis showed that 1D, 2D, and enhancing TB were independent prognostic factors for MOS, with respective hazard ratios of 0.4 (95%CI: 0.2-0.6, p < 0.001), 0.4 (95%CI: 0.3-0.7, p < 0.001) and 0.5 (95%CI: 0.3-0.8, p = 0.003). CONCLUSION: The overall tumor diameter, overall tumor area, and enhancing tumor burden are strong prognostic factors of overall survival in patients with neuroendocrine tumor liver metastases undergoing intra-arterial therapies.

Quantification of contrast-uptake as imaging biomarker for disease progression of renal cell carcinoma after tumor ablation.

BACKGROUND: The prognosis of patients with renal cell carcinoma (RCC) depends greatly on the presence of extra-renal metastases. PURPOSE: To investigate the value of total tumor volume (TTV) and enhancing tumor volume (ETV) as three-dimensional (3D) quantitative imaging biomarkers for disease aggressiveness in patients with RCC. MATERIAL AND METHODS: Retrospective, HIPAA-compliant, IRB-approved study including 37 patients with RCC treated with image-guided thermal ablation during 2007-2015. TNM stage, RENAL Nephrometry Score, largest tumor diameter, TTV, and ETV were assessed on cross-sectional imaging at baseline and correlated with outcome measurements. The primary outcome was time-to-occurrence of extra-renal metastases and the secondary outcome was progression-free survival (PFS). Correlation was assessed using a Cox regression model and differences in outcomes were shown by Kaplan-Meier plots with significance and odds ratios (OR) calculated by Log-rank test/generalized Wilcoxon and continuity-corrected Woolf logit method. RESULTS: Patients with a TTV or ETV > 5 cm3 were more likely to develop distant metastases compared to patients with TTV (OR 6.69, 95% confidence interval [CI] 0.33-134.4, P=0.022) or ETV (OR 8.48, 95% CI 0.42-170.1, P=0.016) < 5 cm3. Additionally, PFS was significantly worse in patients with larger ETV (P = 0.039; median PFS 51.87 months vs. 69.97 months). In contrast, stratification by median value of the established, caliper-based measurements showed no significant correlation with outcome parameters. CONCLUSION: ETV, as surrogate of lesion vascularity, is a sensitive imaging biomarker for occurrence of extra-renal metastatic disease and PFS in patients with RCC.

Interstitial Brachytherapy in Combination With Previous Transarterial Embolization in Patients With Unresectable Hepatocellular Carcinoma.

BACKGROUND/AIM: Treatment of patients with large hepatocellular carcinoma (HCC) remains challenging and survival in advanced tumor stages is limited. This study was conducted to investigate the efficacy of embolization followed by computed tomography (CT)-guided interstitial high-dose-rate brachytherapy (CT-HDRBT) in patients with unresectable HCC. PATIENTS AND METHODS: A total of 47 patients undergoing CT-HDRBT were divided into 2 groups: i) patients previously treated with transarterial chemoembolization (TACE) and ii) patients treated with bland transarterial embolization (TAE). The primary endpoint was overall survival (OS), while secondary endpoints were the time to progression (TTP) and the local progression rate. RESULTS: A total of 78 lesions were treated. The mean size of the main tumors was 58.3 mm. The median OS in TACE and TAE groups was 28.9 months and 32.3 months, respectively (p=NS). The median OS of patients classified as BCLC stage A using the Barcelona Clinic Liver Cancer classification system (BCLC) was 32.3 months, while the median OS of patients in BCLC stage B and C was 36.9 and 17.7 months, respectively. The local progression rate was 7.7% (6/78), with no statistically significant difference between TACE and TAE. The median TTP was significantly longer in the TACE group compared to the TAE group (11.7 months and 10.3 months, respectively). CONCLUSION: Treatment with transarterial embolization and subsequent CT-HDRBT leads to a very promising survival rate for patients with unresectable HCC.