Sage Journals: Discover world-class research

Abstract

Purpose:

To evaluate the feasibility, safety, and efficacy of retroperitoneoscopic microwave ablation (MWA) for clinical stage T_1a (cT_1a) renal tumors.

Patients and Methods:

Consecutive renal cell carcinomas (RCCs) managed since April 2006 with a minimal follow-up of 12 months were included. A total of 23 tumors in 22 patients were managed with laparoscopic MWA. A cooled shaft needle antenna was inserted into the tumor under direct visual guidance. Microwaves were emitted at 50 W for 8 minutes and prolonged as necessary to ensure complete tumor kill. Short-term efficacy was assessed by contrast-enhanced CT at 1, 3, and 6 months, and every 6 months thereafter.

Results:

Pathologic analysis revealed low-grade clear-cell RCC in all patients. Mean tumor size was 2.8 cm (range 0.9–4.0 cm). Excluding 5 lost patients, the initial ablation was successful in 17 (94.4%) of 18 tumors. One patient with an incomplete ablation lesion under strict surveillance had no evidence of disease progression at 31 months of follow-up. No recurrence was observed at a median follow-up of 20 months (range 12–45 mos). All 17 remaining patients had no clinical or radiographic evidence of disease at last follow-up. In addition, complications were mild and tolerable (18.2%), and there was no significant deterioration of renal function.

Conclusions:

Retroperitoneoscopic MWA appears to be a safe and effective technique for cT_1a RCC in selected patients. Additional follow-up is needed to assess long-term effectiveness.

Get full access to this article

View all access options for this article.

References

Gong

, Orvieto

, Zorn

et al. Comparison of laparoscopic and open partial nephrectomy in clinical T1a renal tumors. J Endourol, 2008; 22:953–957.

Leibovich

, Blute

, Cheville

et al. Nephron sparing surgery for appropriately selected renal cell carcinoma between 4 and 7 cm results in outcome similar to radical nephrectomy. J Urol, 2004; 171:1066–1070.

Turna

, Kaouk

, Frota

et al. Minimally invasive nephron sparing management for renal tumors in solitary kidneys. J Urol, 2009; 182:2150–2157.

Brace

. Radiofrequency and microwave ablation of the liver, lung, kidney, and bone: What are the differences? Curr Probl Diagn Radiol, 2009; 38:135–143.

Carrafiello

, Lagana

, Mangini

et al. Microwave tumors ablation: Principles, clinical applications and review of preliminary experiences. Int J Surg, 2008; suppl 1:S65–S69.

Laeseke

, Lee

Jr , Sampson

et al. Microwave ablation versus radiofrequency ablation in the kidney: High-power triaxial antennas create larger ablation zones than similarly sized internally cooled electrodes. J Vasc Interv Radiol, 2009; 20:1224–1229.

Zhang

, Li

, Ma

et al. Retroperitoneal laparoscopic nephron-sparing surgery for renal tumors: Report of 32 cases. Urology, 2005; 65:1080–1085.

Liang

, Wang

, Zhang

et al. Ultrasound guided percutaneous microwave ablation for small renal cancer: Initial experience. J Urol, 2008; 180:844–848.

Matsumoto

, Johnson

, Ogan

et al. Short-term efficacy of temperature-based radiofrequency ablation of small renal tumors. Urology, 2005; 65:877–881.

10.

Naito

, Nakashima

, Kimoto

et al. Application of microwave tissue coagulator in partial nephrectomy for renal cell carcinoma. J Urol, 1998; 159:960–962.

11.

Yoshimura

, Okubo

, Ichioka

et al. Laparoscopic partial nephrectomy with a microwave tissue coagulator for small renal tumor. J Urol, 2001; 165:1893–1896.

12.

Clark

, Woodruff

, Zagoria

, Hall

. Microwave ablation of renal parenchymal tumors before nephrectomy: Phase I study. AJR Am J Roentgenol, 2007; 188:1212–1214.

13.

Hecht

, Israel

, Krinsky

et al. Renal masses: Quantitative analysis of enhancement with signal intensity measurements versus qualitative analysis of enhancement with image subtraction for diagnosing malignancy at MR imaging. Radiology, 2004; 232:373–378.

14.

Hallscheidt

, Bock

, Riedasch

et al. Diagnostic accuracy of staging renal cell carcinomas using multidetector-row computed tomography and magnetic resonance imaging: A prospective study with histopathologic correlation. J Comput Assist Tomogr, 2004; 28:333–339.

15.

Rendon

, Kachura

, Sweet

et al. The uncertainty of radio frequency treatment of renal cell carcinoma: Findings at immediate and delayed nephrectomy. J Urol, 2002; 167:1587–1592.

16.

Weight

, Kaouk

, Hegarty

et al. Correlation of radiographic imaging and histopathology following cryoablation and radio frequency ablation for renal tumors. J Urol, 2008; 179:1277–1281.

17.

Richter

, Kasabian

, Irwin

et al. Accuracy of diagnosis by guided biopsy of renal mass lesions classified indeterminate by imaging studies. Urology, 2000; 55:348–352.

18.

Hinshaw

, Lee

Jr . Image-guided ablation of renal cell carcinoma. Magn Reson Imaging Clin N Am, 2004; 12:429–447.

19.

Stein

, Mayes

, Mouraviev

et al. Persistent contrast enhancement several months after laparoscopic cryoablation of the small renal mass may not indicate recurrent tumor. J Endourol, 2008; 22:2433–2439.

20.

Zhang

, Dong

, Wang

et al. Percutaneous microwave ablation or nephrectomy for VX-2 carcinoma in rabbit kidney. J Urol, 2009; 182:1588–1593.

21.

Eichel

, Kim

, Uribe

et al. Third Prize: Comparison of radical nephrectomy, laparoscopic microwave thermotherapy, cryotherapy, and radiofrequency ablation for destruction of experimental VX-2 renal tumors in rabbits. J Endourol, 2005; 19:1082–1087.

22.

Park

, Anderson

, Matsumoto

et al. Radiofrequency ablation of renal tumors: Intermediate-term results. J Endourol, 2006; 20:569–573.

23.

Bensalah

, Zeltser

, Tuncel

et al. Evaluation of costs and morbidity associated with laparoscopic radiofrequency ablation and laparoscopic partial nephrectomy for treating small renal tumours. BJU Int, 2008; 101:467–471.

24.

Kyle

, Wingo

, Carey

et al. Diagnostic yield of renal biopsy immediately prior to laparoscopic radiofrequency ablation: A multicenter study. J Endourol, 2008; 22:2291–2293.

25.

Bird

, Carey

, Ayyathurai

, Bird

. Management of renal masses with laparoscopic-guided radiofrequency ablation versus laparoscopic partial nephrectomy. J Endourol, 2009; 23:81–88.

26.

Gupta

, Raman

, Leveillee

et al. General anesthesia and contrast-enhanced computed tomography to optimize renal percutaneous radiofrequency ablation: Multi-institutional intermediate-term results. J Endourol, 2009; 23:1099–1105.