Persistent Urine Leak after Cryoablation of a Renal Tumor in a Patient with an Ileal Conduit

Contrast-material-enhanced MR urography in evaluation of postoperative lower urinary tract fistulae and leakages

Urinary fistulas and leakages of lower urinary tract are serious complications of various surgical procedures. Radiologists need to have enough information about these situations to perform precise diagnosis and treatment. Various techniques [such as intravenous pyelography, ultrasound, computed tomography (CT), CT urography, cystoscopy, cystography and magnetic resonance (MR) imaging] are used for the diagnosis of these conditions. Application of all these techniques reduces the comfort and cooperation of the patients and increases the cost. Here we present four postoperative patients with lower urinary tract fistula or leakage. To the best of our knowledge, there is no report regarding the use of contrast-material-enhanced MR urography (CE-MRU) in the demonstration of postoperative lower urinary tract fistulae and leakages. In conclusion, CE-MRU could show the existence and location of the urinary fistulae and leakages clearly without the need for another investigation technique, as described in our patients. Also, CE-MRU is a safe and relatively inexpensive technique that avoids exposure to radiation as well as nephrotoxic and more allergic contrast-material administration.

Thermal ablation of renal cell carcinoma: triage, treatment, and follow-up

The incidence of renal cell carcinoma (RCC) is increasing. With the increasing emphasis on minimally invasive nephron-sparing surgery, thermal ablation is playing a larger role in the management of patients with this disease. This review outlines imaging management, intraoperative and percutaneous ablation, and postprocedural follow-up of RCC.

Cryoablation: mechanism of action and devices

Cryoablation refers to all methods of destroying tissue by freezing. Cryoablation causes cellular damage, death, and necrosis of tissues by direct mechanisms, which cause cold-induced injury to cells, and indirect mechanisms, which cause changes to the cellular microenvironment and impair tissue viability. Cellular injury, both indirect and direct, can be influenced by four factors: cooling rate, target temperature, time at target temperature, and thawing rate. In this review, the authors describe the mechanisms of cellular injury that occur with cryoablation, the major advantages and disadvantages of cryoablation compared with other thermal ablation techniques, and the current commercially available cryoablation ablation systems.

Laparoscopic renal cryoablation: 8-year, single surgeon outcomes

PURPOSE

We present 5 to 11-year (median 8) oncological outcomes after laparoscopic renal cryoablation.

MATERIALS AND METHODS

Between September 1997 and October 2008 we performed renal cryoablation in 340 patients, of whom 80 treated laparoscopically by a single surgeon before October 2003 had a minimum 5-year followup. Followup involved magnetic resonance imaging on postoperative day 1, at 3, 6 and 12 months, and annually thereafter. Cryolesion biopsy was performed at 6 months. All data were prospectively accrued.

RESULTS

In the 80 patients with minimum 5-year followup mean age was 66 years, mean tumor size was 2.3 cm (range 0.9 to 5.0), median American Society of Anesthesiologists score was 3 and mean body mass index was 28 kg/m(2). Five patients had local recurrence, 2 had locoregional recurrence with metastasis and 4 had distant metastasis without locoregional recurrence. Six patients died of cancer. In the 55 patients with biopsy proven renal cell cancer at a median followup of 93 months (range 60 to 132) 5-year overall, disease specific and disease-free survival rates were 84%, 92% and 81%, and 10-year rates were 51%, 83% and 78%, respectively. On multivariate analysis previous radical nephrectomy for RCC was the only significant predictor of disease-free and disease specific survival (p = 0.023 and 0.030, respectively).

CONCLUSIONS

Laparoscopic renal cryoablation is effective oncological treatment for a renal mass in select patients. A disease specific survival rate of 92% at 5 years and 83% at 10 years is possible. Preceding radical nephrectomy for renal cell carcinoma was the only independent factor predicting disease-free and disease specific survival.

Infectious complications after percutaneous radiofrequency ablation of renal cell carcinoma in patients with ileal conduit

Percutaneous renal radiofrequency (RF) ablation is a safe and minimally invasive treatment for renal cell carcinoma. The most common minor complications are pain, self-limiting hematuria, and postablation syndrome. Major complications are rare and include significant hemorrhage and thermal injury to the ureter. Reports of infectious complications after ablation are uncommon, but increased risks in patients with ileal conduits have been reported. The present report describes two patients with ileal conduits who underwent percutaneous renal RF ablation and developed infectious complications (a renal abscess and a calyceal-cutaneous fistula) despite prophylactic antibiotic treatment.

Percutaneous renal cryoablation: current status

Over the last 13 years, renal cryoablation has emerged as a promising technique for the treatment of solid renal tumors. The improvement in imaging modalities such as ultrasound, computed tomography and MRI, as well as the introduction of thinner probes, has led to the spread of the minimally invasive percutaneous approach. We review the historical background of percutaneous renal cryoablation (PRC), present its basic principles, mention the contemporary clinical data and outcomes of this technique and suggest future directions for its wider application in renal tumors. Early results have demonstrated that it may offer an alternative for the treatment of small renal masses with the advantages of minimal complications, spared renal function, decreased overall costs and equivalent oncologic efficacy. Long-term results are required in order to apply this minimally invasive technique to a broader spectrum of patients.