Debra A. Gervais

Image-guided Tumor Ablation: Standardization of Terminology and Reporting Criteria—A 10-Year Update

Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes. Online supplemental material is available for this article .

Image-guided tumor ablation: standardization of terminology and reporting criteria.

The field of interventional oncology with use of image-guided tumor ablation requires standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison between treatments that use different technologies, such as chemical (ethanol or acetic acid) ablation, and thermal therapies, such as radiofrequency (RF), laser, microwave, ultrasound, and cryoablation. This document provides a framework that will hopefully facilitate the clearest communication between investigators and will provide the greatest flexibility in comparison between the many new, exciting, and emerging technologies. An appropriate vehicle for reporting the various aspects of image-guided ablation therapy, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings, are outlined. Methods for standardizing the reporting of follow-up findings and complications and other important aspects that require attention when reporting clinical results are addressed. It is the groups intention that adherence to the recommendations will facilitate achievement of the groups main objective: improved precision and communication in this field that lead to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes. The intent of this standardization of terminology is to provide an appropriate vehicle for reporting the various aspects of image-guided ablation therapy.

Small Renal Mass

A 65-year-old man with a history of well-controlled hypertension presents for a follow-up visit after an incidental finding of a small mass in the right kidney on an abdominal computed tomographic scan (ordered to evaluate lower-quadrant pain, which has since resolved). The mass is 3.2 cm, anterior, heterogeneous, and solid, and is in the right renal hilum near the main renal artery, vein, and ureter; the left kidney appears normal. The patient feels well, his physical examination is unremarkable. His serum creatinine level is 1.2 mg per deciliter. How should this patient be further evaluated and treated?

Long-Term Oncologic Outcomes After Radiofrequency Ablation for T1 Renal Cell Carcinoma

BACKGROUND Radiofrequency ablation (RFA) of renal cell carcinoma (RCC) is used to obtain local control of small renal masses. However, available long-term oncologic outcomes for RFA of RCC are limited by small numbers, short follow-up, and lack of pathologic diagnoses. OBJECTIVE To assess the oncologic effectiveness of RFA for the treatment of biopsy-proven RCC. DESIGN, SETTING, AND PARTICIPANTS Exclusion criteria included prior RCC or metastatic RCC, familial syndromes, or T2 RCC. We retrospectively reviewed long-term oncologic outcomes for 185 patients with sporadic T1 RCC. Median follow-up was 6.43 yr (interquartile range [IQR]: 5.3-7.7). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The chi-square test and Wilcoxon rank-sum tests were used to compare proportions and medians, respectively. Disease-specific survival and overall survival (OS) were calculated using Kaplan-Meier analysis, then stratified by tumor stage, and comparisons were made using log-rank analysis. The 5-yr disease-free survival (DFS) and OS rates are reported. A p value <0.05 was considered statistically significant. RESULTS AND LIMITATIONS Median tumor size was 3 cm (IQR: 2.1-3.9 cm). Tumor stage was T1a: 143 (77.3%) or T1b: 42 (22.7%). Twenty-four patients (13%) were retreated for residual disease. There were 12 local recurrences (6.5%), 6 recurrences in T1a disease (4.2%) and 6 in T1b disease (14.3%) (p=0.0196). Median time to recurrence was 2.5 yr. Local salvage RFA was performed in six patients, of whom five remain disease free at 3.8-yr median follow-up. Tumor stage was the only significant predictor of DFS on multivariate analysis. At last follow-up, 164 patients (88.6%) were disease free (T1a: n=132 [92.3%]; T1b: n=32 [76.2%]; p=0.0038). OS was similar regardless of stage (p=0.06). Five patients developed metachronous renal tumors (2.7%). Four patients developed extrarenal metastases (2.2%), three of whom died of metastatic RCC (1.6%). CONCLUSIONS In poor surgical candidates, RFA results in durable local control and low risk of recurrence in T1a RCC. Higher stage correlates with a decreased disease-free survival. Long-term surveillance is necessary following RFA. Patient selection based on tumor characteristics, comorbid disease, and life expectancy is of paramount importance.

Transcatheter Therapy for Hepatic Malignancy: Standardization of Terminology and Reporting Criteria

The field of interventional oncology includes tumor ablation as well as the use of transcatheter therapies such as embolization, chemoembolization, and radioembolization. Terminology and reporting standards for tumor ablation have been developed. The development of standardization of terminology and reporting criteria for transcatheter therapies should provide a similar framework to facilitate the clearest communication among investigators and provide the greatest flexibility in comparing established and emerging technologies. An appropriate vehicle for reporting the various aspects of catheter directed therapy is outlined, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings. Methods for standardizing the reporting of outcomes toxicities, complications, and other important aspects that require attention when reporting clinical results are addressed. It is the intention of the group that adherence to the recommendations will facilitate achievement of the groups main objective: improved precision and communication for reporting the various aspects of transcatheter management of hepatic malignancy that will translate to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes.

Image-guided tumor ablation: standardization of terminology and reporting criteria--a 10-year update.

Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes.

Impact of Obesity on Medical Imaging and Image-Guided Intervention

OBJECTIVE The purpose of this article is to discuss the impact of obesity on medical imaging and provide some solutions that are currently available to tackle the challenges of imaging obese patients. CONCLUSION Increasingly, radiologists are asked to image morbidly obese patients. The challenges facing radiology departments include difficulties in transporting patients to the department, inability to accommodate large patients on currently designed imaging equipment, and difficulties in acquiring desired image quality.

Renal Mass and Localized Renal Cancer: AUA Guideline

Purpose: This AUA Guideline focuses on evaluation/counseling and management of adult patients with clinically localized renal masses suspicious for cancer, including solid‐enhancing tumors and Bosniak 3/4 complex‐cystic lesions. Materials and Methods: Systematic review utilized research from the Agency for Healthcare Research and Quality and additional supplementation by the authors and consultant methodologists. Evidence‐based statements were based on body of evidence strength Grade A/B/C (Strong/Moderate/Conditional Recommendations, respectively) with additional statements presented as Clinical Principles or Expert Opinions. Results: Great progress has been made since the previous guidelines on management of localized renal masses were released (2009). The current guidelines provide updated, evidence‐based recommendations regarding evaluation/counseling of patients with clinically localized renal masses, including the evolving role of renal mass biopsy. Given great variability of clinical, oncologic and functional characteristics, index patients are not utilized and the panel advocates individualized counseling/management. Management options (partial nephrectomy/radical nephrectomy/thermal ablation/active surveillance) are reviewed including recent data about comparative effectiveness and potential morbidities. Oncologic issues are prioritized while recognizing that functional outcomes are of great importance for survivorship for most patients with localized kidney cancer. A more restricted role for radical nephrectomy is recommended following well‐defined selection criteria. Priority for partial nephrectomy is recommended for clinical T1a lesions, along with selective use of thermal ablation, particularly for tumors ≤3.0 cm. Important considerations for shared decision‐making about active surveillance are explicitly defined. Conclusions: Several factors should be considered during counseling/management of patients with clinically localized renal masses, including general health/comorbidities, oncologic potential of the mass, pertinent functional issues and relative efficacy/potential morbidities of various management strategies.

Radiofrequency Ablation of Renal Cell Carcinoma

Small renal cell carcinomas of less than 4 cm diameter have been detected increasingly in asymptomatic patients because of the widespread use of cross-sectional imaging. Radical or partial nephrectomy is generally considered the reference for the treatment of a solitary renal cell carcinoma. However, for those patients who are not candidates for surgery, minimally invasive procedures may be desirable. Although percutaneous radiofrequency ablation for the treatment of renal cell carcinoma is a recent innovation, the results of preliminary clinical series and animal studies are encouraging, and show it to be technically feasible with minimal morbidity. In this article, we review the technique, indications, imaging findings, as well as the results of clinical and animal studies of radiofrequency ablation for the treatment of renal cell carcinoma.

Radiation Dose Reduction with Hybrid Iterative Reconstruction for Pediatric CT

PURPOSE To assess image quality and radiation dose reduction with hybrid iterative reconstruction of pediatric chest and abdominal computed tomographic (CT) data compared with conventional filtered back projection (FBP). MATERIALS AND METHODS A total of 234 patients (median age, 12 years; age range, 6 weeks to 18 years) underwent chest and abdominal CT in this institutional review board-approved HIPAA-compliant retrospective study. CT was performed with a hybrid adaptive statistical iterative reconstruction (ASIR)-enabled 64-detector row CT scanner. Scanning protocols were adjusted for clinical indication and patient weight to enable acquisition of reduced-dose CT images in all patients, and tube current was further lowered for ASIR protocols. Weight, age, and sex were recorded, and objective noise was measured in the descending thoracic aorta for chest CT and in the liver for abdominal CT. Of the 234 consecutive patients who underwent ASIR-enabled CT (115 chest and 119 abdominal examinations), 70 patients had undergone prior FBP CT. ASIR and FBP CT studies (29 chest and 41 abdominal studies) in these 70 patients were reviewed for image quality, artifacts, and diagnostic confidence by two pediatric radiologists working independently. Data were analyzed with multiple paired t tests. RESULTS Compared with FBP, ASIR enabled dose reduction of 46.4% (3.7 vs 6.9 mGy) for chest CT and 38.2% (5.0 vs 8.1 mGy) for abdominal CT (P < .0001). Both radiologists deemed image quality of and diagnostic confidence with ASIR and FBP CT images as acceptable, without any artifacts. Despite the lower radiation dose used, ASIR images (chest, 10.7 ± 2.5 [mean ± standard deviation]; abdomen, 11.8 ± 3.4) had substantially less objective noise than did FBP images (chest, 13.3 ± 3.8; abdomen, 13.8 ± 5.2) (P = .001, P =.006, respectively). CONCLUSION Use of a hybrid iterative reconstruction technique, such as ASIR, enables substantial radiation dose reduction for pediatric CT when compared with FBP and maintains image quality and diagnostic confidence.