PubMed Health⌕ Search

Biomedical subjects

Ronald J Zagoria

Publications and source records attributed to Ronald J Zagoria.

At least 19 recordsLinked to original sources

Residual and recurrent disease following renal energy ablative therapy: a multi-institutional study.

PURPOSE: In this study we detail the incidence and pattern of residual and recurrent disease after radio frequency ablation or cryoablation of a renal mass and, using this information, determine reasonable minimum recommendations for when to perform surveillance imaging during year 1 after treatment. To our knowledge no evidence based guidelines exist for determining how or when followup abdominal imaging should be performed after renal energy ablative therapy. MATERIALS AND METHODS: We reviewed treatment and followup information of patients who underwent radio frequency ablation or cryoablation for a renal mass at 7 institutions. Postoperative monitoring was performed using a variety of surveillance schedules. RESULTS: Of 616 patients 63 were found to have residual or recurrent disease after primary radio frequency ablation (13.4%) or cryoablation (3.9%) for a median of 8.7% in 7 institutions. Most incomplete treatments (70%) were detected within the first 3 months. After salvage ablative therapy was rendered, therapy failed in only 4.2%. At a mean followup of 2 years patients with residual or recurrent disease had an overall survival rate of 82.5% and a 2-year metastasis-free survival rate of 97.4% for those with localized, unilateral renal tumors. CONCLUSIONS: In most cases initial treatment failure was detected within the first 3 months after treatment. Our findings support a minimum of 3 to 4 imaging studies in year 1 after ablative therapy, and at months 1, 3, 6 (optional) and 12.

Catheter Ablation↗

Staging and current treatment of hepatocellular carcinoma.

Early-stage hepatocellular carcinoma (HCC) is typically clinically silent, and HCC is often advanced at first manifestation. Without treatment, the 5-year survival rate is less than 5%. The selected treatment depends on the presence of comorbidity; tumor size, location, and morphology; and the presence of metastatic disease. Complete surgical resection followed by hepatic transplantation offers the best long-term survival, but few patients are eligible for this therapy. All other therapies are palliative. Radiofrequency ablation is the preferred method for managing unresectable small HCCs that are few in number. More widespread disease is treated with percutaneous therapies such as chemoembolization and selective internal radiation therapy. Systemic administration of biologic and chemotherapeutic agents is minimally successful in slowing the growth of HCC and typically is used to control symptoms in patients with overwhelming disease. A multidisciplinary approach that includes surgery, systemic therapy, and radiation therapy and that is based on the cooperation of radiation oncologists, interventional and diagnostic radiologists, hepatologists, and pathologists may offer the best chance of a cure or at least a longer and more normal life. To participate effectively in this effort, radiologists must be familiar with staging and treatment options for HCC and with the factors that affect the choice of management method.

Adult↗

Evaluation of liver metastases after radiofrequency ablation: utility of 18F-FDG PET and PET/CT.

OBJECTIVE: Our objective was to review the CT appearance of liver metastases after radiofrequency ablation and to describe the imaging findings of and utility of (18)F-FDG PET and PET/CT in assessing tumor recurrence after ablation. CONCLUSION: (18)F-FDG PET and PET/CT can provide added diagnostic information compared with conventional imaging in patients after radiofrequency ablation of liver metastases and can be useful in guiding repeat ablation procedures.

Catheter Ablation↗

Radiofrequency ablation of renal tumors.

Radiofrequency ablation (RFA) of renal tumors is a relatively new treatment modality in the armamentarium of urologic surgeons. One of the challenges of this technique is attaining a zone of tissue destruction sufficient enough to kill the targeted tumor. Technologic innovations have aided in this effort. The clinical experience with RFA of renal tumors suggests that small, exophytic tumors may be more readily ablated. Although there is much optimism with regard to this technology, further study is required to better define the oncologic efficacy and refine proper patient selection.

Carcinoma, Renal Cell↗

Classic signs in uroradiology.

The language of radiology is rich with descriptions of imaging findings, often metaphorical, which have found common usage in the day-to-day practice of genitourinary radiology. These "classic signs" give us confidence in our diagnosis. Some of the signs have become so familiar to us that they are referred to as an "Aunt Minnie." When the sign is invoked, or an Aunt Minnie is recognized, it often brings an impression of the image to mind, and it may have specific diagnostic and pathologic implications. The article uses classic signs accumulated from the literature to review a variety of pathologic conditions in the urinary tract.

Humans↗

Imaging-guided radiofrequency ablation of renal masses.

Substantial and growing evidence indicates that imaging-guided percutaneous radiofrequency ablation of small renal cell carcinomas (RCCs) is effective for complete tumor eradication. The rate of successful radiofrequency treatment of small RCCs ranges from 79% to 97%, with a 1% rate of serious complications. For patients who are considered high-risk candidates for nephrectomy, percutaneous radiofrequency ablation represents another treatment option. The article summarizes the published results for this technique and also describes the indications, techniques, procedural risks, and applications for percutaneous radiofrequency ablation of RCCs. The successful use of radiofrequency ablation for treatment of recurrent and metastatic RCCs is also described.

Adult↗

Percutaneous CT-guided radiofrequency ablation of renal neoplasms: factors influencing success.

OBJECTIVE: The objective of our study was to evaluate the success rate for radiofrequency ablation of renal tumors and to determine the risk of serious complications. CONCLUSION: No serious complications occurred after 27 CT-guided radiofrequency ablation sessions in 22 patients. In total, no residual tumor was detected on follow-up contrast-enhanced CT or MRI 1-35 months (mean, 7 months) after final tumor ablation in 20 (91%) of 22 patients. Two patients with residual viable tumor deferred further treatment. Complete tumor ablation was achieved after a single treatment session in 83% of patients, and in 8% of patients after subsequent ablation sessions. Size was the major determinant for achieving tumor eradication with a single session of ablation, with all 11 tumors 3 cm or smaller being completely ablated after one session. Tumor location, histology, and the presence of renal disease did not correlate with treatment success. Contrast-enhanced CT performed immediately after ablation is reliable to exclude residual viable tumor. CT-guided radiofrequency ablation of renal tumors is safe and has a high rate of success in the treatment of small renal tumors, with no evidence of recurrence at midterm follow-up of treated patients.

Aged↗

Percutaneous image-guided radiofrequency ablation of renal malignancies.

There is a growing body of experience supporting the use of image-guided RFA for the treatment of primary RCC. Because surgical resection is a technique with low mortality, and a proved success rate that is high, this must remain standard therapy for patients with potentially curable RCC. Some patients with low-stage RCC, however, may not be surgical candidates. Image-guided RFA is an option for treatment of these patients. In addition, image-guided RFA shows promise for the successful care of other patients with RCC. In particular, RFA has been used successfully for the treatment of intractable hematuria resulting from an RCC; local recurrences of RCC, both for attempted cure and for palliation of symptoms; and finally for the treatment of isolated metastases from RCC. As with the treatment of primary RCC, the data remain limited for these applications. This technique should be reserved until after standard therapies have been exhausted. It seems likely that some form of image-guided percutaneous tumor therapy, such as RFA, will become an alternative treatment modality in some patients with potentially curable RCC.

Catheter Ablation↗

Computerized tomography guided access for percutaneous nephrostolithotomy.

PURPOSE: Access for percutaneous nephrostolithotomy (PNL) using conventional fluoroscopic guidance may carry an increased risk of damage to surrounding organs in patients with renal calculi and aberrant anatomy. In these situations cross-sectional anatomical imaging may facilitate safe percutaneous access. We describe our experience with computerized tomography (CT) guided percutaneous access for such patients undergoing PNL. MATERIALS AND METHODS: Between June 2000 and December 2001, 154 patients underwent PNL at our institution. Five of these patients (3%) required a total of 6 percutaneous access tracks under CT guidance. All patients in this group had anatomical abnormalities precluding standard access to the collecting system without risk to adjacent organs. These abnormalities included a retrorenal colon in 2 and a severely distorted body habitus due to spinal dysraphism in 3. RESULTS: Percutaneous access was achieved without complication in all cases. At subsequent PNL 5 of the 6 renal units (83%) were rendered completely stone-free. CONCLUSION: CT guided percutaneous access is infrequently required for PNL. However, there is a select group of patients with anatomical anomalies that may predictably require this procedure to facilitate safe and efficacious PNL.

Adult↗

Percutaneous radiofrequency ablation of hepatic metastases for symptomatic relief of neuroendocrine syndromes.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of percutaneous radiofrequency ablation of hepatic neuroendocrine metastases for symptomatic relief of neuroendocrine syndromes. CONCLUSION: Percutaneous radiofrequency ablation, a minimally invasive technique, is an effective and safe way to reduce systemic symptoms in patients with hepatic metastases from neuroendocrine neoplasms.

Adult↗

Phase II trial of radio frequency ablation of renal cancer: evaluation of the kill zone.

PURPOSE: We report on the pathological evaluation of renal tumors after intraoperative radio frequency ablation performed immediately before surgical nephrectomy. MATERIALS AND METHODS: Ten patients with renal tumors were enrolled in a prospective, Institutional Review Board approved phase II trial of radio frequency ablation. Following surgical exposure of the kidney a single 12-minute radio frequency ablation of the tumor was performed using the Radionics Cool-tip RF Radio Frequency Ablation System (Radionics, Burlington, Massachusetts). The tumor was then excised via radical or partial nephrectomy. Gross and histological evaluations of the tumor were performed, including evaluation with nicotinamide adenine dinucleotide vital staining. RESULTS: All 10 tumors were confirmed histologically to be renal cell carcinoma. Mean tumor size was 3.2 cm. (range 1.4 to 8.0). Of the 10 tumors 8 were completely ablated with a mean treatment margin of 6.75 mm. (range 2 to 13). Of the 2 tumors that were incompletely treated 1 never attained a temperature sufficient for tissue destruction and the other measured 8 cm., far exceeding the expected ablation volume of treatment protocol. CONCLUSIONS: This study represents the initial report of the histological outcome of saline cooled radio frequency ablation of renal tumors. Our data indicate that it can completely destroy renal cancers while transmitting minimal collateral damage to surrounding renal parenchyma. Further investigation is required to determine long-term oncological outcome.

Adult↗

Complications from radiofrequency ablation of liver metastases.

The objective of this study is to evaluate complications from radiofrequency ablation of liver metastases. Eighty-one liver tumors in 38 consecutive patients were treated with radiofrequency ablation. All patients had one to six metastases treated in a single session. Eight patients underwent radiofrequency ablation intraoperatively after laparotomy and the remaining 30 patients were treated percutaneously with CT or ultrasound guidance. A total of 43 radiofrequency ablation procedures were studied. There was one (2%) mortality related to a hepatic abscess development 8 days after the procedure. One patient (3%) required a blood transfusion. Three patients (8%) developed severe upper abdominal or pleuritic chest pain that persisted several days after the procedure. We conclude that radiofrequency ablation of liver metastases is associated with a low rate of serious complications (two of 38; 5%). Complications requiring treatment usually develop several days after the procedure.

Adult↗

Percutaneous nephrostomy with extensions of the technique: step by step.

Minimally invasive therapy in the urinary tract begins with renal access by means of percutaneous nephrostomy. Indications for percutaneous nephrostomy include urinary diversion, treatment of nephrolithiasis and complex urinary tract infections, ureteral intervention, and nephroscopy and ureteroscopy. Bleeding complications can be minimized by entering the kidney in a relatively avascular zone created by branching of the renal artery. The specific site of renal entry is dictated by the indication for access with consideration of the anatomic constraints. Successful percutaneous nephrostomy requires visualization of the collecting system for selection of an appropriate entry site. The definitive entry site is then selected; ideally, the entry site should be subcostal and lateral to the paraspinous musculature. Small-bore nephrostomy tracks can be created over a guide wire coiled in the renal pelvis. A large-diameter track may be necessary for percutaneous stone therapy, nephroscopy, or antegrade ureteroscopy. The most common extension of percutaneous nephrostomy is placement of a ureteral stent for treatment of obstruction. Transient hematuria occurs in virtually every patient after percutaneous nephrostomy, but severe bleeding that requires transfusion or intervention is uncommon. In patients with an obstructed urinary tract complicated by infection, extensive manipulations pose a risk of septic complications.

Humans↗