ENDOUROLOGY & LAPAROSCOPY

Comparison of laparoscopic and open partial nephrectomy for tumor in a solitary kidney
Lane BR, Novick AC, Babineau D, Fergany AF, Kaouk JH, Gill IS
Glickman Urological Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA
J Urol. 2008; 179: 847-51; discussion 852

• Purpose: We compared the postoperative and renal functional outcomes of patients undergoing open or laparoscopic partial nephrectomy for tumor in a solitary functioning kidney.
• Materials and Methods: Between 1999 and 2006, 169 open and 30 laparoscopic partial nephrectomies were performed for 7 cm or smaller tumors in a solitary functioning kidney. Data were collected in an institutional review board approved registry and median follow-up was 2.0 years. Preoperative and postoperative glomerular filtration rates were estimated with the abbreviated Modification of Diet in Renal Disease equation.
• Results: By 3 months after open or laparoscopic partial nephrectomy, the glomerular filtration rate decreased by 21% or 28%, respectively (p = 0.24). Postoperative dialysis was required acutely after 1 open partial nephrectomy (0.6%) and 3 laparoscopic partial nephrectomies (10%, p = 0.01), and dialysis dependent end stage renal failure within 1 year occurred after 1 open partial nephrectomy (0.6%) and 2 laparoscopic partial nephrectomies (6.6%, p = 0.06). In multivariate analysis warm ischemia time was 9 minutes longer (p < 0.0001) and the chance of postoperative complications was 2.54-fold higher (p < 0.05) with laparoscopic partial nephrectomy. Longer warm ischemia time (more than 20 minutes) and preoperative glomerular filtration rate were associated with poorer postoperative glomerular filtration rate in multivariate analysis. Notwithstanding the association with warm ischemia time, the surgical approach itself was not an independent predictor of postoperative glomerular filtration rate (p = 0.77).
• Conclusions: While laparoscopic partial nephrectomy is technically feasible for tumor in a solitary kidney, warm ischemia time was longer and complication rates higher compared with open partial nephrectomy. In addition, although average loss of renal function at 3 months is equivalent (after accounting for warm ischemia time), a greater proportion of patients required dialysis temporarily or permanently after laparoscopic partial nephrectomy in this initial series. Therefore, open partial nephrectomy may be the preferred nephron sparing approach at this time for these patients at high risk for chronic kidney disease.
  
  
• Editorial Comment
  The authors should be congratulated for this enlightening, instructive manuscript.
  Laparoscopic partial nephrectomy is a complex procedure with a steep learning curve but it has been demonstrated by several investigators including the present authors that it is a technically feasible surgery for small tumors even in solitary kidneys.
  The warm ischemia time (WIT) was longer and complication rates higher compared with open partial nephrectomy but the loss of renal function was equal in 3 months for both groups.
  Nonetheless, this minimally invasive approach is another viable treatment option that can be reserved for patients that can tolerate a slightly longer WIT (9 min. longer than open surgery).

Dr. Fernando J. Kim
Chief of Urology, Denver Health Med Ctr
Assistant Professor, Univ Colorado Health Sci Ctr
Denver, Colorado, USA
E-mail: fernando.kim@uchsc.edu