The current status of thermal ablation in the management of T1b renal masses.

The role of thermal ablation in the management of T1b renal masses is not well defined. The purpose of this review is to examine current evidence for cryoablation, radiofrequency ablation, and microwave ablation of T1b renal masses as well as review current AUA and EAU guidelines for thermal ablation of T1b masses. Given the size of these tumors, adjunctive maneuvers are often necessary to ensure patient safety and protect vital adjacent structures.

Feasibility and outcomes of percutaneous thermal ablation of hepatocellular carcinoma in a transplanted allograft.

PURPOSE: To examine the safety, feasibility, and oncologic control following percutaneous image-guided thermal ablation of hepatocellular carcinoma (HCC) in a transplanted allograft. MATERIALS AND METHODS: Retrospective review was performed to identify patients who underwent liver transplantation for HCC and subsequently underwent percutaneous hepatic thermal ablation for recurrent HCC within the allograft between January 1st, 2000-September 1st, 2016. Eleven patients with hepatic allograft HCC underwent twelve percutaneous thermal ablation procedures to treat 16 lesions. Patient, procedural characteristics, and local oncologic efficacy were reviewed. Complications were characterized via the Common Terminology for Clinically Adverse Events nomenclature [CTCAE] v4.03). RESULTS: Eleven transplant recipients underwent treatment of 16 HCC tumors in their allografts during 12 ablation sessions. Mean follow-up time was 25 months (range 2-96 months). Local oncologic control was achieved in 10 of 11 tumors (91%) with imaging follow-up. One patient (8%) with Roux-en-Y biliary reconstruction developed a major complication with hepatic abscess. CONCLUSION: Thermal ablation of recurrent HCC in transplanted allografts can be accomplished safely with acceptable rates of local control for patients with duct-to-duct biliary reconstruction. Due to the high number of patients deemed surgically unresectable, the morbidity of surgical resection, the side effects of targeted therapies, and significant mortality associated with recurrences in the transplanted allograft, patients may benefit from percutaneous thermal ablative treatments. Further study is needed to assess the role of thermal ablation in allograft HCC recurrences as primary therapy or in a multimodality approach with emerging systemic therapies.

A prospective genome-wide study of prostate cancer metastases reveals association of wnt pathway activation and increased cell cycle proliferation with primary resistance to abiraterone acetate-prednisone.

Background: Genomic aberrations have been identified in metastatic castration-resistant prostate cancer (mCRPC), but molecular predictors of resistance to abiraterone acetate/prednisone (AA/P) treatment are not known. Patients and methods: In a prospective clinical trial, mCRPC patients underwent whole-exome sequencing (n = 82) and RNA sequencing (n = 75) of metastatic biopsies before initiating AA/P with the objective of identifying genomic alterations associated with resistance to AA/P. Primary resistance was determined at 12 weeks of treatment using criteria for progression that included serum prostate-specific antigen measurement, bone and computerized tomography imaging and symptom assessments. Acquired resistance was determined using the end point of time to treatment change (TTTC), defined as time from enrollment until change in treatment from progressive disease. Associations of genomic and transcriptomic alterations with primary resistance were determined using logistic regression, Fisher's exact test, single and multivariate analyses. Cox regression models were utilized for determining association of genomic and transcriptomic alterations with TTTC. Results: At 12 weeks, 32 patients in the cohort had progressed (nonresponders). Median study follow-up was 32.1 months by which time 58 patients had switched treatments due to progression. Median TTTC was 10.1 months (interquartile range: 4.4-24.1). Genes in the Wnt/ß-catenin pathway were more frequently mutated and negative regulators of Wnt/ß-catenin signaling were more frequently deleted or displayed reduced mRNA expression in nonresponders. Additionally, mRNA expression of cell cycle regulatory genes was increased in nonresponders. In multivariate models, increased cell cycle proliferation scores (≥ 50) were associated with shorter TTTC (hazard ratio = 2.11, 95% confidence interval: 1.17-3.80; P = 0.01). Conclusions: Wnt/ß-catenin pathway activation and increased cell cycle progression scores can serve as molecular markers for predicting resistance to AA/P therapy.

A Single-Institution Experience in Percutaneous Image-Guided Biopsy of Malignant Pleural Mesothelioma.

PURPOSE: Mesothelioma has been considered a difficult pathologic diagnosis to achieve via image-guided core needle biopsy. The purpose of this study was to assess the diagnostic sensitivity of percutaneous image-guided biopsy for diagnosis of pleural mesothelioma. MATERIALS AND METHODS: Retrospective review was performed to identify patients with a confirmed diagnosis of pleural mesothelioma and who underwent image-guided needle biopsy between January 1, 2002, and January 1, 2016. Thirty-two patients with pleural mesothelioma were identified and included for analysis in 33 image-guided biopsy procedures. Patient, procedural, and pathologic characteristics were recorded. Complications were characterized via standardized nomenclature [Common Terminology for Clinically Adverse Events (CTCAE)]. RESULTS: Percutaneous image-guided biopsy was associated with an overall sensitivity of 81%. No CTCAE clinically significant complications were observed. No image-guided procedures were complicated by pneumothorax or necessitated chest tube placement. No patients had tumor seeding of the biopsy tract. CONCLUSION: Percutaneous image-guided biopsy can achieve high sensitivity for pathologic diagnosis of pleural mesothelioma with a low procedural complication rate, potentially obviating need for surgical biopsy.

Evaluation of infectious complications following percutaneous liver ablation in patients with bilioenteric anastomoses.

PURPOSE: Prior bilioenteric anastomosis (BEA) has been associated with elevated risk of abscess formation after thermal ablation of hepatic tumors. We assessed the incidence of hepatic abscess after thermal ablation in a BEA cohort treated with extended antibiotic regimens following ablation. MATERIALS AND METHODS: Retrospective review was performed to identify patients with BEA who underwent percutaneous hepatic thermal ablation between January 1, 2003-September 1, 2016. Fifteen patients with BEA underwent 18 percutaneous thermal ablation procedures. Patient and procedural characteristics were reviewed, as well as the antibiotic regiment utilized post ablation. Complications were characterized via standardized nomenclature [Common Terminology for Clinically Adverse Events (CTCAE) v4.03]. RESULTS: Fifteen patients with BEA underwent treatment of 49 liver lesions during 18 ablation sessions. Mean follow-up in these patients was 39 months (range 3-138 months). Two patients (11%) developed hepatic abscesses, both of which occurred within 45 days of the ablation procedure while the patients were still on extended prophylactic antibiotic therapy. No additional CTCAE clinically significant complications were observed. CONCLUSION: Thermal ablation of hepatic tumors can be accomplished safely in patients with BEA. Long-term post-procedural antibiotics may mitigate the risk of hepatic abscess formation. Due to the high number of patients who are deemed surgically unresectable, patients with BEA may have limited alternate treatment modalities and percutaneous hepatic thermal ablative treatments warrant consideration.

Treatment of neuroendocrine cancer metastatic to the liver: the role of ablative techniques.

Carcinoid tumors and islet cell neoplasms are neuroendocrine neoplasms with indolent patterns of growth and association with bizarre hormone syndromes. These tumors behave in a relatively protracted and predictable manner, which allows for multiple therapeutic options. Even in the presence of hepatic metastases, the standard of treatment for neuroendocrine malignancy is surgery, either with curative intent or for tumor cytoreduction, i.e., resection of 90% or more of the tumor volume. Image-guided ablation, as either an adjunct to surgery or a primary treatment modality, can be used to treat neuroendocrine cancer metastatic to the liver. Image-guided ablative techniques, including radiofrequency ablation, alcohol injection, and cryoablation, can be used in selected patients to debulk hepatic tumors and improve patient symptoms. Although long-term follow-up data are not available, the surgical literature indicates that significant ablative debulking may improve patient survival. In this review, we discuss metastatic neuroendocrine disease and its treatment options, especially image-guided ablative techniques.