Laparoscopic vs. Percutaneous Radio Frequency Ablation of Renal Masses

 uncategorized  No Responses »
Feb 282012
 

Comparison of Safety, Renal Function Outcomes and Efficacy of Laparoscopic and Percutaneous Radio Frequency Ablation of Renal Masses

Young E. E., Castle S. M., Gorbatiy V. and Leveillee R. J.

J Urol (2012)

PURPOSE: With the increased incidence of low stage renal cancers, thermal ablation technology has emerged as a viable treatment option. Current AUA (American Urological Association) guidelines include thermal ablation as a treatment modality for select individuals. We compared the laparoscopic and percutaneous approach for the radio frequency ablation of renal tumors under the guidance of urological surgeons.

MATERIALS AND METHODS: We reviewed our radio frequency ablation database of patients with renal masses undergoing laparoscopic or computerized tomography guided percutaneous radio frequency ablation with simultaneous peripheral fiberoptic thermometry from November 2001 to January 2011 at a single tertiary care center. Data were collected on patient demographics, and surgical and clinicopathological outcomes stratified by approach.

RESULTS: A total of 298 patients with 316 renal tumors underwent laparoscopic (122 tumors) or computerized tomography guided (194 tumors) radio frequency ablation. There were no statistically significant differences between the laparoscopic and computerized tomography guided radio frequency ablation groups with respect to patient demographics, complication rates and renal functional outcomes (p >0.05). The 3-year Kaplan-Meier estimation of radiographic recurrence-free probability was 95% for computerized tomography guided radio frequency ablation and 94% for laparoscopic radio frequency ablation (p = 0.84). Subanalysis of the 212 (67%) renal cell carcinoma tumors showed a 3-year Kaplan-Meier estimation of oncologic recurrence-free probability (post-ablation biopsy proven viable tumor) of 94% for computerized tomography guided radio frequency ablation and 100% for laparoscopic radio frequency ablation (p = 0.16). Median followup was 21 months for laparoscopic radio frequency ablation) and 19 months for computerized tomography guided radio frequency ablation.

CONCLUSIONS: Laparoscopic and computerized tomography guided radio frequency ablation appear safe and effective with statistically equivalent rates of complications and recurrence

Commentary:

Encouraging results for RFA from a group with a great deal of experience. It appears from this data we can choose either percutaneous (when feasible) or laparoscopic based upon tumor location, without concern for significant difference in outcomes. Unfortunately, we still have no randomized trials of ablative therapy for small renal masses.

 Posted by at 12:07 pm

Focused ultrasound to expel calculi from the kidney.

 urolithiasis  No Responses »
Feb 222012
 

Shah A., Harper J. D., Cunitz B. W., Wang Y. N., Paun M., Simon J. C., Lu W., Kaczkowski P. J. and Bailey M. R.

J Urol 187(2):739-43 (2012)

PURPOSE: A persistent stone burden after renal stone treatment may result in future patient morbidity and potentially lead to additional surgery. This problem is particularly common after treatment of lower pole stones. We describe a potential noninvasive therapeutic option using ultrasound waves to create a force sufficient to aid in stone fragment expulsion.

MATERIALS AND METHODS: Human stones were implanted by retrograde ureteroscopy or antegrade percutaneous access in a live porcine model. The calibrated probe of a system containing ultrasound imaging and focused ultrasound was used to target stones and attempt displacement. To assess for injury an additional 6 kidneys were exposed for 2 minutes each directly to the output used for stone movement. Another 6 kidneys were exposed to more than twice the maximum output used to move stones. Renal tissue was analyzed histologically with hematoxylin and eosin, and nicotinamide adenine dinucleotide staining.

RESULTS: Stones were moved to the renal pelvis or ureteropelvic junction by less than 2 minutes of exposure. Stone velocity was approximately 1 cm per second. There was no tissue injury when tissue was exposed to the power level used to move stones. Localized thermal coagulation less than 1 cm long was observed in 6 of 7 renal units exposed to the level above that used for ultrasonic propulsion.

CONCLUSIONS: Transcutaneous ultrasonic propulsion was used to expel calculi effectively and safely from the kidney using a live animal model. This study is the first step toward an office based system to clear residual fragments and toward use as a primary treatment modality in conjunction with medical expulsive therapy for small renal stones

Comment:

Very interesting preliminary work in an animal model. Could external energy like this facilitate ureteroscopic or percutaneous treatment? Perhaps we could move fragments out of the lower pole, or move small fragments out of the kidney during the procedure, eliminating the need to pass them later. It might be possible to avoid a second puncture, or move that elusive fragment into the renal pelvis during percutaneous nephrolithotomy. I look forward to updates from the UW group.

Computed tomography-determined stone-free rates for ureteroscopy of upper-tract stones.

 ureteroscopy, urolithiasis  No Responses »
Dec 142010
 

Macejko A, Okotie OT, Zhao LC, Liu J, Perry K, Nadler RB.

Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.

Comment in:

Outcomes after treatment for urolithiasis vary greatly depending upon the imaging modality used to evaluate for residual stones. Commonly used modalities such as plain film “KUB”, renal ultrasound, and in the past, IVP can easily miss small residual fragments. Stone protocol abdominal CT scans are now used more often for the diagnosis and monitoring of patients with urolithiasis. All residual fragments after treatment including tiny, perhaps clinically insignificant fragments, are visualized using CT postoperatively. This is a nice study presenting their stone free rate following ureteroscopic treatment as determined by CT scan for follow-up. They present the results of 92 patients (113 ureteroscopies) for renal and ureteral stones. Stone free was determined by the strictest definition of no stone fragment on CT scan/ The overall stone free rate was 50.4% (80% for ureteral only, 34.8% for renal).

These results likely come as no surprise to most urologists. As the authors point out, the fate of these remaining fragments after ureteroscopy found on CT, most of them tiny, have not been specifically studied. There is no question that reporting of results after treatment for urolithiasis should be standardized, and include other outcomes such as quality of life measures. For now, it will have to suffice that the methods of postoperative imaging and definitions of success be clearly described in each study.

Is There a Role for Tamsulosin in the Treatment of Distal Ureteral Stones of 7 mm or Less? Results of a Randomised, Double-Blind, Placebo-Controlled Trial

 medical expulsive therapy, urolithiasis  No Responses »
Sep 082009
 

European Urology 56(2009) 407-412 (pubmed link)

Hermans T, Sauerman P, Rufibach K, Frauenfelder T, Sulser T, and Strebel RT

A recent randomized double blinded study that did not show different rate of successful stone passage for Tamsulosin vs. placebo (86.7% vs 88.9%), but the Tamsolosin group did pass their stones earlier (7 d vs. 10 d on average) and required less pain medications. It is quite possible that the advantage of the use of alpha blockers relates less to an improved ability to pass the stones, but rather less pain, and therefore more likely to tolerate the time required to pass the stone.

Alfuzosin to relieve ureteral stent discomfort: a prospective, randomized, placebo controlled study.

 stents, ureteroscopy  1 Response »
Dec 302008
 

Beddingfield R, Pedro RN, Hinck B, Kreidberg C, Feia K, Monga M. J Urol. 2009 Jan;181(1):170-6. (PubMed Link)

This randomized, placebo controlled trial assessed the usefulness of Alfuzosin (Uroxatrol) to control stent related symptoms after ureteroscopy. Patients were asked to complete the validated “Ureteral Stent Symptom Questionnaire” before and 3 days after ureteroscopy. Although the patients in the Alfuzosin arm reported less kidney pain during sleep, less frequent use of painkillers for kidney pain, and less interference with life from the kidney pain, the overall amount of narcotics used per day was no different.

A previous study using tamsulosin showed improvement in the “Ureteral Stent Symptom Questionnaire” and Qol scores.A comparison between the two medications might prove useful, as the autonomic effects of the two medications are different as evidenced by the different rates of ejaculatory dysfunction in a prior study.

Effect of diltiazem on kidney function during laparoscopic surgery

 laparoscopy, transplant  No Responses »
Dec 302008
 

Kim JY, Lee KC, Kim HS, Jo YY, Kwak HJ.Surg Endosc. 2008 Dec 6 (PubMed link)

A randomized trial involving 32 patients, half of whom received the control (saline infusion) and the other half received a continuous infusion of diltiazem (2 mug/kg/min). The diltiazem group had significantly higher creatinine clearance during the pneumoperitoneum than the control group, but both groups equalized their urine output by 2 hours postoperative. This may be a useful treatment to prevent renal damage in patients with renal insufficiency who are undergoing laparoscopic procedures. It might also be useful in improving immediate graft function following laparoscopic donor nephrectomy.