Technical difficulties in retroperitoneoscopic radical nephrectomy. Is tumor location important

Introduction
It is generally admitted that the results of radio- and chemotherapy on renal cell carcinoma (RCC) are poor compared with other neoplasms. The modern surgical management of renal cell carcinoma (RCC) originated from Robson et al (1) description of radical nephrectomy in the 1960's.
At present both radical and partial nephrectomies may be performed by either open surgery or minimally invasive surgery. A high number of statistical reports confirm the oncological effectiveness of laparoscopic techniques in the treatment of RCC (2-4).
It is unanimously accepted that radical nephrectomy is the golden standard for an RCC larger than 4 cm. Due to cumulative and increasing experience, laparoscopic radical nephrectomy may be performed by both transperitoneal and retroperitoneal routes, both techniques having good long-term surgical and oncological outcomes (5-9). Both techniques reproduce laparoscopically the principles of open radical nephrectomy: initial approach of the renal hilum (first the artery and then the vein), excision of the kidney together with the perirenal fat and Gerota's fascia, with or without concomitant adrenalectomy (6-8, 10).
Laparoscopy in general and the urological laparoscopy in particular, have experienced amazing development in the last 10 years, with results that could be hardly imagined in the past. Though the learning curve is long and any operation may entail complications, the postoperative evolution and the rate of complications are better with laparoscopic interventions, even major ones, than with classical techniques. Postoperative care and costs are also reduced (10, 20).
To rank the complexity of different laparoscopic procedures, Guillonneau et al (21) have proposed a scoring system that assigns every laparoscopic procedure an objective degree of difficulty according to three different criteria: technical difficulty, operative risk and the attention required. Regarding the laparoscopic radical nephrectomy, in addition to the smaller working space, tumor location on the posterior aspect of the kidney or close to the renal hilum, could increase the technical difficulty.
The aim of our study was to assess how tumor location does influence the difficulty of the retroperitoneoscopic radical nephrectomy (RRN).

Patients and method
We performed a nonrandomized prospective study on 116 patients with localized renal cell carcinoma who underwent RRN, between January 2000 - 2005. Patients with tumors larger than 9 cm were excluded from the study. The regional ethical committee approved the study, and all patients provided written informed consent.
Clinical work-up included clinical exam, biochemistry, Doppler ultrasound, intravenous pyelogram, CT scan or MRI, and chest X Ray. All patients were suitable with regard to anesthetic risks. CT scan or MRI was used to assess the tumor stage and anatomic details necessary for operative planning.
The patients were stratified in regard to the tumor location in two groups. Twenty-nine patients with tumors located close to renal hilum or on the posterior aspect of the kidney (Gr. A) were compared with 87 patients with tumor at distance from the renal hilum (Gr. B) in terms of operative time, intra-operative blood loss, and difficulty of the dissection. The two groups were similar in terms of mean age, sex ratio, body weight, and side of the affected kidney and tumor size (Table 1).
The operative technique
The patient under general anesthesia is placed on the operative table in a lumbotomy position. The retroperitoneal access is achieved by a minimal incision of 1.5-2 cm. on the tip of the 12th rib, followed by digital and balloon dissection under visual control. At the level of this incision a 12-mm trocar is placed that will ensure the use of the endostapler (fig. 1).
A second incision is performed at the costo-muscular angle, where a second, 5-mm trocar is placed. The 12-mm telescope is placed over the iliac crest on the median axillary line. We prefer the 35 degree telescope.
One or two additional trocars (10 and 5 mm) are placed at the level of the anterior axillary line, to be used for retraction and aspiration.
After identifying the psoas muscle, Gerota's fascia is sectioned using the harmonic scalpel. The dissection is targeted to the renal hilum with early identification of the renal artery, without dislodging the kidney (Fig. 2). After clamping and sectioning of the renal artery (Fig. 2b) the renal vein is identified, which is also dissected and sectioned using the endostapler.

In the case of tumors situated on the posterior valve, or which protrude at the level of the renal hilum, the approach of the renal pedicle is more difficult because of more profuse bleeding, adhesions and smaller operative field requiring additional retraction (Fig. 3).
The perifascial dissection starts at the level of the upper renal pole and continues downwards till the complete freeing of the kidney (fig. 4), identification of the ureter and its dissection down to the iliac vessels.
In the case of large tumors and of those situated at the upper pole, adrenalectomy is also performed. In the case of stage T2 tumors but which adhere to the peritoneum, the block excision of the peritoneum is performed.
In order to avoid tumoral dissemination the surgical specimen is extracted using a hand-port device mounted at the level of an ilio-inguinal incision of 6 cm and sent for histopathological examination (fig. 5).
The two patients groups were assessed from the point of view of difficulty, duration of the operation and intraoperative hemorrhage.
The degree of difficulty of each operative stage - artery dissection, vein dissection, perifascial dissection - was assessed using a 3 points scale: 1 - easy, 2 - moderate, 3 - difficult. Grade 4 - very difficult, was not used because all laparoscopic radical nephrectomies were finalized without conversion to open surgery.
Results
In the Gr.A, the operative time was longer (117.28 min vs. 94.63 min, p<0.001) and blood loss was higher (291.86 ml vs. 199.54 ml, p<0.001). The dissection of the renal pedicle was also more difficult in the Gr. A for artery dissection (G3 27.59% vs. 11.49%, p=0.0202) or for vein dissection (G3 20.69% vs. 8.05%, p=0.0321), while perifascial dissection was less frequently difficult (G3 10.34% vs. 28.74%, p=0.0237). Pathologic tumor stage T3a frequency was 17.24% in Gr. A and 13.79% in Gr. B, p=0.65 (table 2).

Discussion
Laparoscopy has a well established place in the therapy of RCC and continues to grow in importance. In our institute we prefer the retroperitoneal approach of the urological structures, and from our experience of about 1500 laparoscopic urological interventions, this approach has yielded results comparable to the transperitoneal approach, with the additional advantage of an initial direct approach of the renal pedicle and a lower number of complications (8, 10, 21-26). Perihilar lymphadenectomy is also feasible. Extended lymphadenectomy is not required since it does not improve survival (27).
The difficulty of a small operative field is easily overcome by practice (10).
In our opinion the location of the tumor near the renal hilum or on the posterior aspect of the kidney increases the difficulty of the dissection of the renal pedicle (23). For tumors with these locations, grade 3 of difficulty was more frequent regarding the dissection of both the artery and the vein. In these cases, the increased dissection difficulty of the renal pedicle is due to tumor position and increased vascularization.
On the other hand, in the case of peripheral tumors, in which the pedicle dissection is often easy, grade 3 of difficulty was more frequently found regarding perifascial dissection because of the adhesions, block excision with peritoneal patch being required in some cases.
On pathologic examination, the resection margins were negative in all patients suggesting that the technique achieved this objective.
In our experience, the 5 years DSS rates were 98.1% for pT1, 74.04% for pT2, 61.11% for pT3a tumors smaller or equal to 7 cm, and 42.75% for pT3a tumors larger than 7 cm.

Conclusion
Tumor location close to the renal hilum or on the posterior aspect of the kidney increases the difficulty of the renal pedicle dissection.

Take home message
Tumor location influence the degree of difficulty in retroperitoneoscopic radical nephrectomy as have been showed in this paper.

References
1. Robson, C.J., Churchill, B.M., and Anderson, W. - The results of radical nephrectomy for renal cell carcinoma. J. Urol., 1969, 101:297.
2. Steinberg, A.P., Finelli, A., Desai, M.M., Abreu, S.C., Ramani, A.P., Spaliviero, M., Rybicki, L., Kaouk, J., Novick, A.C., Gill, I.S. - Laparoscopic radical nephrectomy for large (greater than 7 cm, T2) renal tumors., J. Urol., 2004, 172:2172.
3. Finelli, A., Kaouk, J.H., Fergany, A.F., Abreu, S.C., Novick, A.C., Gill, I.S. - Laparoscopic cytoreductive nephrectomy for metastatic renal cell carcinoma., BJU Int., 2004, 94:291.
4. Gilbert, S.M., Murphy, A.M., Katz, A.E., Goluboff, E.T., Sawczuk, I.S., Olsson, C.A., Benson, M.C., McKiernan, J.M. - Reevaluation of TNM staging of renal cortical tumors: recurrence and survival for T1N0M0 and T3aN0M0 tumors are equivalent. Urology, 2006, 68:287.
5. Clayman, R.V., Kavoussi, L.R., Soper, N.J., Dierks, S.M., Meretyk, S., Darcy, M.D., Roemer, F.D., Pingleton, E.D., Thomson, P.G., Long, S.R. -Laparoscopic nephrectomy: initial case report. J. Urol., 1991, 146:278.
6. Chan, D.Y., Cadeddu, J.A., Jarrett, T.W., Marshall, F.F., Kavoussi, L.R. - Laparoscopic radical nephrectomy: cancer control for renal cell carcinoma. J. Urol., 2001, 166:2095.
7. Ono, Y., Kinukawa, T., Hattori, R., Gotoh, M., Kamihira, O., Ohshima, S. - The long-term outcome of laparoscopic radical nephrectomy for small renal cell carcinoma. J. Urol., 2001, 165:1867.
8. Abbou, C.C., Cicco, A., Gasman, D., Hoznek, A., Antiphon, P., Chopin, D.K., Salomon, L. - Retroperitoneal laparoscopic versus open radical nephrectomy. J. Urol., 1999, 161:1776.
9. Gill, I.S., Meraney, A.M., Schweizer, D.K., Savage, S.S., Hobart, M.G., Sung, G.T., Nelson, D., Novick, A.C. - Laparoscopic radical nephrectomy in 100 patients: a single center experience from the United States. Cancer, 2001, 92:1843.
10. Gill, I.S., Schweizer, D., Hobart, M.G., Sung, G.T., Klein, E.A., Novick, A.C. - Retroperitoneal laparoscopic radical nephrectomy: the Cleveland clinic experience. J. Urol., 2000,163:1665.
11. Cadeddu, J.A., Wolfe, J.S. Jr, Nakada, S., CHEN, R., SHALHAV, A., BISHOFF, J.T., HAMILTON, B., SCHULAM, P.G., DUNN, M., HOENIQ, D., FABRIZIO, M., MEDICAM, S., AVERCH, T.D. - Complications of laparoscopic procedures after concentrated training in urological laparoscopy. J. Urol., 2001, 166:2109.
12. Gagner, M., Pomp, A., Heniford, B.T., PHARAD, D., LACROIX, A. - Laparoscopic adrenalectomy: lessons learned from 100 consecutive procedures. Ann Surg., 1997, 226:238.
13. Gill, I.S., Kavoussi, L.R., Clayman, R.V., EMRLICM, R., EVANS, R., FUCHS, G., GERSHAM, A., HULBERT, JC., McDOUGALL, E.M., ROSENTHAL, T., SCHVESS, W., SHEPARD, T. - Complications of laparoscopic nephrectomy in 185 patients: a multiinstitutional review. J. Urol., 1995, 154:479.
14. Higashihara, E., Baba, S., Nakagawa, K., MURAI, M., GO, H., TAKEDA, M., TAKAHASHI, K., SUZUKI, K., FUJITA, K., ONO, Y., OHSHIMA, S., MATSUDA, T., TERACHI, T., YOSHIDA, O. - Learning curve and conversion to open surgery in cases of laparoscopic adrenalectomy and nephrectomy. J. Urol., 1998, 159:650.
15. Parra, R.O., Hagood, P.G., Boullier, J.A., CUMMINGS, J., MEHAN, D. - Complications of laparoscopic urological surgery: experience at St. Louis University. J. Urol., 1994, 151:681.
16. Fahlenkamp, D., Rassweiler, J., Fornara, P., FREDE, T., LOENIMG, S.A. - Complications of laparoscopic procedures in urology: experience with 2,407 procedures at 4 German centers. J. Urol., 1999, 162:765.
17. Soulie, M., Salomon, L., Seguin, P., MERVAT, C., MOULY, P., HOZNEK, A., ANTIPHON, P. - Multi- institutional study of complications in 1085 laparoscopic urologic procedures. Urology, 2001, 58:899.
18. Soulie, M., Seguin, P., Richeux, L., MOULY, P., VAZZOLER, N., PONTONNIER, F., PLANTE, P. - Urological complications of laparoscopic surgery: experience with 350 procedures at a single center. J. Urol., 2001, 165:1960.
19. Meraney, A.M., Abd-El Samee, A., and Gill, I.S. - Vascular and bowel complications during retroperitoneal laparoscopic surgery. J. Urol., 2002, 168:1941.
20. Vallancien, G., Cathelineau, X., Baumert, H., DOUBLET, J.D., GUILLONNEAU, B. - Complications of transperitoneal laparoscopic surgery in urology: review of 1,311 procedures at a single center. J. Urol., 2002, 168:23.
21. Guillonneau, B., Abbou, C.C., Doublet, J.D., Gaston, R., Janetschek, G., Mandressi, A., Rassweiler, J.J., Vallancien, G. - Proposal for a "European Scoring System for Laparoscopic Operations in Urology". Eur. Urol., 2001, 40:2.
22. Steinberg, A.P., Finelli, A., Desai, M.M., Abreu, S.C., Ramani, A.P., Spaliviero, M., Rybicki, L., Kaouk, J., Novick, A.C., Gill, I.S. - Laparoscopic radical nephrectomy for large (greater than 7 cm, T2) renal tumors. J. Urol., 2004, 172:2172.
23. LUCAN, M., LUCAN, V., ELEC, F., IACOB, G., BARBOS, A. - Technical difficulties in retroperitoneoscopic radical nephrectomy. Is tumor location important? European Urology Video Journal, 2006, 12.4:23.
24. Desai, M.M., Strzempkowski, B., Matin, S.F., Steinberg, A.P., Ng, C., Meraney, A.M., Kaouk, J.H., Gill, I.S. - Related Articles, Links: Prospective randomized comparison of transperitoneal versus retroperitoneal laparoscopic radical nephrectomy. J. Urol., 2005, 173:38.
25. Nambirajan, T., Jeschke, S., Al-Zahrani, H., Vrabec, G., Leeb, K., Janetschek, G. - Prospective, randomized controlled study: transperitoneal laparoscopic versus retroperitoneoscopic radical nephrectomy. Urology, 2004, 64:919.
26. Rodriguez, A., and Pow-Sang, J.M. - Laparoscopic Surgery in Urologic Oncology, Cancer Control, 2006, 13:169.
27. Mickisch, G., Carballido, J., Hellsten, S., Schulze, H., Mensink, H. - Guidelines on renal cell cancer. Eur. Urol., 2001, 40:252.

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