Pattern of retained contrast on immediate postprocedure computed tomography (CT) after particle embolization of liver tumors predicts subsequent treatment response.

PURPOSE: To determine if the pattern of retained contrast on immediate postprocedure computed tomography (CT) after particle embolization of hepatic tumors predicts modified Response Evaluation Criteria in Solid Tumors (mRECIST) response. MATERIALS AND METHODS: This study was approved by the Institutional Review Board with a waiver of authorization. One hundred four liver tumors were embolized with spherical embolic agents (Embospheres, Bead Block, LC Bead) and polyvinyl alcohol. Noncontrast CT was performed immediately after embolization to assess contrast retention in the targeted tumors, and treatment response was assessed by mRECIST criteria on follow-up CT (average time 9.0 ± 7.7 weeks after embolization). Tumor contrast retention (TCR) was determined based on change in Hounsfield units (HUs) of the index tumors between the preprocedure and immediate postprocedure scans; vascular contrast retention (VCR) was rated; and defects in contrast retention (DCR) were also documented. The morphology of residual enhancing tumor on follow-up CT was described as partial, circumferential, or total. Association between TCR variables and tumor response were assessed using multivariate logistic regression. RESULTS: Of 104 hepatic tumors, 51 (49%) tumors had complete response (CR) by mRECIST criteria; 23 (22.1%) had partial response (PR); 21 (20.2%) had stable disease (SD); and 9 (8.7%) had progressive disease (PD). By multivariate analysis, TCR, VCR, and tumor size are independent predictors of CR (p = 0.02, 0.05, and 0.005 respectively). In 75 tumors, DCR was found to be an independent predictor of failure to achieve complete response (p < 0.0001) by imaging criteria. CONCLUSION: TCR, VCR, and DCR on immediate posttreatment CT are independent predictors of CR by mRECIST criteria.

Ki-67 is a prognostic biomarker of survival after radiofrequency ablation of liver malignancies.

PURPOSE: To assess the predictive value of examinations of tissue adherent to multitined electrodes on local tumor progression-free survival (LPFS) and overall survival (OS) after liver tumor radiofrequency ablation (RFA). METHODS: An institutional review board-approved, Health Insurance Portability and Accountability Act-compliant review identified 68 liver tumors treated with RFA in 63 patients with at least 3 years' follow-up. Tissue adherent to the electrode after liver tumor RFA was evaluated with proliferation (Ki-67) and apoptotic (caspase-3) markers. LPFS and OS were evaluated by Kaplan-Meier methodology and the log-rank test. Multivariate analysis assessed the effect of tumor size, pathology, and post-RFA tissue characteristics on LPFS and OS. RESULTS: Post-RFA tissue examination classified 55 of the 68 tumors as completely ablated with coagulation necrosis, with cells positive for caspase-3 and negative for Ki-67 (CN). Thirteen had viable Ki-67-positive tumor cells. Mean liver tumor size was larger in the viable (V) group versus the CN group (3.4 vs. 2.5 cm, respectively; P = .017). For the V and CN groups, respectively, local tumor progression occurred in 12 (92 %) of 13 and 23 (42 %) of 55 specimens. One, 3-, and 5-year LPFS was 8 %, 8 %, and 8 %, and 79 %, 47 %, and 47 % (P < .001) for the V and CN groups, respectively. During a 63-month median follow-up, 92 % of patients in the V group and 58 % in the CN group died, resulting in 1-, 3-, and 5-year OS of 92 %, 25 %, and 8 % vs. 92 %, 59 %, and 33 % (P = .032), respectively. CONCLUSIONS: Ki-67-positive tumor cells on the electrode after liver tumor RFA is an independent predictor of LPFS and OS. Size, initially thought to be an independent risk factor for local tumor progression in tumors 3-5 cm, does not hold its significance at long follow-up.

Current management of pyogenic liver abscess: surgery is now second-line treatment.

BACKGROUND: The objective of this study was to examine the current treatment for liver abscess and to assess the factors associated with failure of percutaneous drainage. STUDY DESIGN: Records of 58 patients with pyogenic hepatic abscess, from 1998 to 2009, were examined. Clinicopathologic variables were analyzed as predictors of failure of percutaneous drainage using multivariable logistic regression. The results of surgical intervention after failure of percutaneous treatment were also examined. RESULTS: Fifty-one patients (88%) had a history of malignancy including pancreas (36%), cholangiocarcinoma (17%), colon (12%), and gallbladder (10%). Recent hepatic artery embolization or radiofrequency ablation preceded development of abscess in 13 patients (22%). Fifteen patients (26%) had evidence of biliary tract communication, and 14 of 15 (93%) of these patients had concomitant biliary tract obstruction. Percutaneous drainage was successful in 38 patients (66%) with a median drain dwell time of 26 days (range 3 to 319 days). Five patients (9%) required operative intervention and 2 of these patients (3% overall) died postoperatively from septic complications. Fifteen patients (26%) died with percutaneous drains in place; 9 (60%) of these patients died of cancer progression without evidence of sepsis. Independent predictors of failure of percutaneous drainage included abscesses containing yeast (p = 0.003) and communication of the abscess cavity with the biliary tree (p = 0.02). CONCLUSIONS: Pyogenic hepatic abscess was treated successfully in the majority of patients with advanced malignancy, although mortality remained high. The presence of yeast and communication with an untreated obstructed biliary tree were associated with failure of percutaneous drainage. The need for surgical salvage was associated with a high mortality.