Watershed Hepatocellular Carcinomas: The Risk of Incomplete Response following Transhepatic Arterial Chemoembolization.

PURPOSE: Hepatocellular carcinomas (HCCs) bridging two or more Couinaud-Bismuth segments of the liver ("watershed tumors") can recruit multiple segmental arteries. The primary hypothesis of this study was that fewer watershed tumors show complete response (CR) after chemoembolization, with shorter time to local recurrence. Secondary analysis on the impact on transplantation eligibility in the presence of progressive disease was also performed. MATERIALS AND METHODS: A total of 155 transplantation-eligible patients whose HCC met Milan criteria (watershed, n = 83; nonwatershed, n = 72) and was treated with chemoembolization were included. Cone-beam computed tomography (CT) was used for guidance and for confirmation of circumferential uptake. Local response to chemoembolization per modified Response Evaluation Criteria In Solid Tumors and local disease-free survival (DFS) for the index tumor were calculated. Differences were assessed by univariate and multivariate analyses. RESULTS: CR after a single of chemoembolization was observed in 55.4% of watershed tumors and in 72.2% of nonwatershed tumors (P = .045). Estimated DFS intervals were 151 days (95% confidence interval [CI], 93-245 d) and 336 days (95% CI, 231-747 d; P = .040) in the watershed and nonwatershed groups, respectively. Worse DFS was observed with a Model for End-Stage Liver Disease score > 20 (P = .0001), higher Child-Pugh-Turcotte score (P = .049), and watershed location (P = .040). Waiting list drop-off rates were statistically similar between groups. CONCLUSIONS: Hepatocellular carcinomas located in the watershed region of the liver have a poorer response to chemoembolization than those located elsewhere. These tumors are associated with worse DFS and require additional treatments to maintain transplantation eligibility per Milan criteria. Cone-beam CT can identify crossover supply and confirm complete geographic drug uptake, possibly reducing (but not eliminating) the risk of incomplete response.

Persistent CT nephrograms following cardiac catheterisation and intervention: initial observations.

OBJECTIVES: To describe persistent nephrographic patterns detected by unenhanced renal CT at 24 h after cardiac catheterisation and intervention. METHODS: This prospective study was Health Insurance Portability and Accountability Act-compliant and institutional review board approved. Twenty-nine patients (20 men, nine women; average age 63.27 and range 41-85 years) agreed to undergo unenhanced dual-energy computed tomography (CT) limited to their kidneys at 24 h after cardiac catheterisation. CT attenuation values (Hounsfield units) were made from the cortical and medullary regions and single kidney total parenchymal iodine values (milligrams) were measured. Spearman's rank correlation coefficient and a two-sided Fisher's exact test were used in the statistics. RESULTS: Focal nephrograms were observed in at least one kidney (range, one to five regions per kidney) in 10/29 (34%) of patients and bilateral global nephrograms in 13/29 (45%) of patients. Focal nephrograms correlated with cardiac catheterisation fluoroscopic time (r = 0.48; P = 0.0087). For global nephrograms, the total iodine content of right and left kidneys correlated with fluoroscopic time (r = 0.79 and 0.76; P < 0.0001, respectively) and the amount of contrast material (CM) used (r = 0.77 and r = 0.74; P < 0.0001, respectively). CONCLUSION: Persistent focal and global nephrograms occur commonly as assessed by non-contrast CT at 24 h post cardiac catheterisation and our observations suggest they could be related to procedural factors.

Treatment planning and volumetric response assessment for Yttrium-90 radioembolization: semiautomated determination of liver volume and volume of tumor necrosis in patients with hepatic malignancy.

PURPOSE: The primary purpose of this study was to demonstrate intraobserver/interobserver reproducibility for novel semiautomated measurements of hepatic volume used for Yttrium-90 dose calculations as well as whole-liver and necrotic-liver (hypodense/nonenhancing) tumor volume after radioembolization. The secondary aim was to provide initial comparisons of tumor volumetric measurements with linear measurements, as defined by Response Evaluation Criteria in Solid Tumors criteria, and survival outcomes. METHODS: Between 2006 and 2009, 23 consecutive radioembolization procedures were performed for 14 cases of hepatocellular carcinoma and 9 cases of hepatic metastases. Baseline and follow-up computed tomography obtained 1 month after treatment were retrospectively analyzed. Three observers measured liver, whole-tumor, and tumor-necrosis volumes twice using semiautomated software. RESULTS: Good intraobserver/interobserver reproducibility was demonstrated (intraclass correlation [ICC] > 0.9) for tumor and liver volumes. Semiautomated measurements of liver volumes were statistically similar to those obtained with manual tracing (ICC = 0.868), but they required significantly less time to perform (p < 0.0001, ICC = 0.088). There was a positive association between change in linear tumor measurements and whole-tumor volume (p < 0.0001). However, linear measurements did not correlate with volume of necrosis (p > 0.05). Dose, change in tumor diameters, tumor volume, and necrotic volume did not correlate with survival (p > 0.05 in all instances). However, Kaplan-Meier curves suggest that a >10% increase in necrotic volume correlated with survival (p = 0.0472). CONCLUSION: Semiautomated volumetric analysis of liver, whole-tumor, and tumor-necrosis volume can be performed with good intraobserver/interobserver reproducibility. In this small retrospective study, measurements of tumor necrosis were suggested to correlate with survival.