Kazunori Kihara md ph d, Department of Urology and Reproductive Medicine Graduate School, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. Email: firstname.lastname@example.org
Abstract Aim: To assess the feasibility of our portless endoscopic radical nephrectomy via a single minimum incision, which narrowly permitted extraction of the specimen in the initial 80 patients.
Methods: Radical nephrectomy was carried out extraperitoneally in patients with T1–3aN0M0 renal tumors using an endoscope through a single minimum incision without trocar ports and gas. All the instruments used were reusable.
Results: The average length of incision, operative time and estimated blood loss were 6.6 cm (range, 4–9 cm), 3. 1 h (range, 1.7–5.6 h) and 324 mL (range, 10–2288 mL), respectively. The complication rate was 2.5% (2/80); complications included injury of the pleura and hemorrhage from the vena cava, both of which were repaired by suture during operation. Transfusion was performed in three patients (3.8%). Average times to oral feeding and walking were both 1.4 days. Wound pain was minimal and analgesics were generally not required by the second postoperative day. In patients with larger incisions (7 cm or more), estimated blood loss increased (approximately 100 mL on average) and oral feeding resumed later (0.3 days on average), relative to patients with smaller incisions (6 cm or less). However, overall results were similar between the two patient groups. In patients with a large tumor (7 cm or greater), operative time did not increase and complications and transfusions were both avoided.
Conclusion: Portless endoscopic radical nephrectomy via a single minimum incision is a safe, reproducible, cost-effective and minimally invasive treatment option for patients with T1–3aN0M0 renal tumors.
Radical nephrectomy for the treatment of renal cell carcinoma has most typically been performed by standard open surgery. Recently, laparoscopic or hand-assisted laparoscopic radical nephrectomy have been introduced as minimally invasive techniques for radical nephrectomy; these techniques are being increasingly performed worldwide.1–7 Although these advanced techniques have been reported to be safe, effective and to result in an improved quality of life for the patients, relative to the standard open surgery, the following problems remain: (i) wounds for the trocar ports in addition to the incision for extraction of the intact specimen; (ii) high equipment cost; (iii) use of CO2 insufflation, which carries a risk of pulmonary embolism or venous thrombosis; and (iv) intraperitoneal injury, which has a risk of postoperative intestinal obstruction in a transperitoneal approach.2–7
To reduce or eliminate the above problems while preserving minimal invasiveness, we investigated portless endoscopic radical nephrectomy via a single minimum incision, which narrowly permits extraction of the specimen, without gas, without trocar ports and without injury to the peritoneum. The working space is made by dissecting along the anatomical plane using an endoscope, and is maintained with long retractors. In the present report we describe our operative technique and present the results of the initial consecutive 80 patients. These results are compared with results from other operations using the same and/or different operative techniques.
From August 1998 to June 2003, 80 consecutive patients with renal cell carcinoma, or suspected renal cell carcinoma, underwent radical nephrectomy by portless endoscopic surgery (PLES) via a single minimum incision. Patients ranged in age from 35 to 89 years (average 60 years). Fifty-eight patients were men and 22 were women. Thirty-seven patients suffered from right renal tumor and 43 had left renal tumor. Patients included in the study had tumors of specifications T1–3aN0M0, according to the 2002 TNM classification. Informed consent was obtained from each patient.
An outline of the technique has been previously reported.8,9 After provision of general anesthesia, the patient was placed in the flank position over the break of the table. A 4–6-cm incision was made obliquely forward following the line of the 12th rib. When the tumor was large or cystic, or when the perinephric fat was rich, the incision was extended to the length that narrowly permitted extraction of the intact specimen during operation. The distal end of the 12th rib was removed if necessary. The external oblique and internal oblique muscles were split and the transversalis fascia was exposed. After incising the fascia, dissection was performed between the psoas fascia, posteriorly, and Gerota's fascia, anteriorly. Gerota's fascia was bluntly pushed medially off the psoas muscle to allow immediate access to the renal artery and vein (Fig. 1). During the above dissection, the ureter was readily identified near the lower pole of the kidney.
At the beginning of dissection along Gerota's fascia, a 30° endoscope was inserted through the incision and a video monitor was attached so that the field could be viewed both through the incision and on the screen. The endoscope was held by one of the operators and moved on each occasion to the best position for viewing the operative fields. Subsequent procedures were carried out using a combination of video image and direct vision for the operator, and using only video image for assistants. After dissecting along the posterior Gerota's fascia, the perihilar connective tissue and lymphatics were removed using sharp and blunt dissection to identify the renal artery, and the artery was circumferentially mobilized. Then, the renal artery was doubly ligated and divided. Next, the renal vein was freed, doubly ligated and divided. For the left side tumor, the adrenal, lumbar, or gonadal venous branches were ligated and divided. The ureter previously identified was freed as low as possible and then ligated and divided. Next, dissection was performed between the peritoneum, anteriorly, and Gerota's fascia, posteriorly. Gerota's fascia was bluntly pushed laterally off the peritoneum to allow immediate access to the renal hilus and the adrenal gland (Fig. 1). The perinephric fat was transversely divided at the level of transection of the ureter to the aorta on the left side and to the vena cava on the right side. By retracting the kidney covered with Gerota's fascia down with the retractor, the cranial border of Gerota's fascia was dissected. The adrenal gland was removed with the kidney when necessary. After freeing the remaining renal attachments, the specimen was extracted through the incision using a flexible catcher (Kobayashi Medical Co., Osaka, Japan; Figs 2,3). After shifting the freed kidney to one side using a retractor, from the other side the catcher was inserted in the working space through the incision. The mouth of the catcher was moved toward the kidney and the kidney was pushed toward the mouth with a finger inserted through the incision. The incision was extended to the length that narrowly permitted extraction of the specimen if necessary.
Lymphadenectomies were carried out in cases where apparent, enlarged lymph nodes were observed or palpated. After placing a drainage tube through the incision, the transverse, internal oblique and external oblique muscles were approximated. The skin was then closed. We used long retractors for maintaining the working space, and a Knot slide (Kobayashi Medical Co., Osaka, Japan) for ligation (Fig. 2), which facilitated procedures deep in the wound. All the instruments used were reusable.
Statistical analyses were performed using Mann–Whitney U-tests.
The operation was successfully carried out in all 80 cases. The duration of the operation was 1.7–5.6 h (mean, 3.1 h). The estimated blood loss was 10–2288 mL (mean, 324 mL). The length of skin incision was 4–9 cm (mean, 6.6 cm). Three patients underwent transfusion. There were two complications during operation; these included incision of the pleura and hemorrhage from the vena cava, both of which were repaired by suture during operation. No complications were observed postoperatively. The complication rate was 2.5% (2/80). The size of the tumors was 1–9 cm (mean, 4.1 cm). The pathological examination revealed renal cell carcinoma in 74 patients and benign tumors in six patients, including five hemodialysis patients (two adenomas, two hematomas and one angiomyolipoma) and one non-hemodialysis patient who had angiomyolipoma that lacked the lipoma element. The final pathological stages of the 74 patients with renal cell carcinoma were pT1N0M0 in 62, pT2N0M0 in six and pT3N0M0 in six. Average times to oral feeding and walking were both 1.4 days (Table 1). Wound pain was minimal and analgesics were generally not required by the second postoperative day. The follow-up period was 2–43 months (mean, 23 months). There were no local and incision-site recurrences. Two patients with T1 and T2 tumors developed pulmonary and osseous metastases, respectively.
Table 1. Baseline demographics, intraoperative and postoperative data
Size of incision
Large tumor (≥7 cm)
†, Data presented as mean (range).
‡, Final length is presented. The incision is extended during operation; the length of extension depends on the case.
§, Postoperative days until the patients can walk long distances with full diet, without drainage tube and analgesics.
¶, Incision of the pleura and hemorrhage from the vena cava. Both were repaired by suture during operation.
Patients were divided into two groups according to the size of their skin incision. For analytical purposes, patients with a smaller incision (4–6 cm) were placed in the SI group, whereas patients with a larger incision (7–9 cm) were placed in the LI group. Results from comparisons between these groups are displayed in Table 1. In summary, the average size of the tumor was 3.6 cm (range, 1–6.6 cm) in the SI group and 4.7 cm (range, 1–9.0 cm) in the LI group (P = 0.027). The average operative time was 3.1 h (range, 1.7–5.6 h) in the SI group and 3.2 h (range, 2.1–5.1 h) in the LI group. Average blood loss was 233 mL (range, 10–813 mL) in the SI group and 420 mL (range, 50–2288 mL) in the LI group (P = 0.014). The average number of days to oral feeding was 1.2 in the SI group and 1.5 in the LI group (P = 0.04). The average number of days to walking was 1.5 in the SI group and 1.4 in the LI group.
In eight patients with a large tumor (7 cm or greater), the average operative time was 2.9 h (range, 2.6–4.9 h) and the average blood loss was 386 mL (range, 120–1000 mL). There were no complications and transfusions were not performed. Average times to oral feeding and walking were 1.6 and 1.4 days, respectively.
Results from the present study indicate that radical nephrectomy can be carried out safely through a single minimum incision, which narrowly permits extraction of the kidney (covered with Gerota's fascia using an endoscope), without trocar ports, without gas and without injury to the peritoneum. Our results by PLES stood comparison with those reported by others using laparoscopic and hand-assisted laparoscopic techniques (Tables 1,2).3,5–7,10,11 The standard incision of our procedure (4–6 cm) was less than that of hand-assisted laparoscopic radical nephrectomy (7–8 cm), which allowed insertion of a hand into the operative field, and was similar to that of laparoscopic radical nephrectomy with intact specimen extraction (Tables 1,2). Additional wounds for the trocar ports are necessary for the above two laparoscopic operations. Specimen fragmentation or morcellation for extraction during laparoscopic radical nephrectomy has been introduced and accepted at several centers10–12 (Table 2). However, such trials have not succeeded in demonstrating their advantages compared with intact extraction,10,12 and many surgeons have stated that intact specimen extraction does not appear to increase postoperative incisional morbidity significantly.4 Intact extraction enables an accurate study of the surgical margins and pathological staging of the tumor, which avoids the risk of tumor cell spread.11
Table 2. Reports of open, hand-assisted laparoscopic and laparoscopic radical nephrectomy
In the initial series of the present study, for intact extraction of the large or cystic tumor, we made an incision larger than 4–6 cm at the beginning of the operation and extended it during the operation if necessary. However, in many of the latter series, the standard 4–6 cm incision was made first, even in these cases with large or cystic tumors, and the incision was extended by as little as possible at the time of specimen extraction. In most cases, the specimens were extracted through incisions smaller than the specimens themselves (Fig. 2). Notably, in patients with larger incisions (7 cm or more), estimated blood loss increased (approximately 100 mL on average) and oral feeding resumed later (0.3 days on average), relative to patients from the SI group. However, the results of patients with the larger incisions were almost as favorable as those of patients with a standard incision (6 cm or less). In patients with a large tumor (7 cm or greater), the operative time did not increase, and complications and transfusions were both avoided (Table 1). In short, PLES via a minimum incision appears to provide a safe, reproducible and minimally invasive technique for the removal of renal tumors, including large ones.
Focussing on advantages of the presented procedure, the fact that the length of the incision can be adjusted at any time during the operation might contribute to the safety of the technique and to the avoidance of complications without the need for patient selection. Relatively low operating room costs are also an advantage of the presented procedure, because most of the instruments used are the same as those used in the standard open surgery and all of the instruments are reusable. In the present study, we used long instruments for manipulation deep in the wound and a Knot slide for ligation. Patients are able to benefit from the advantages of the minimally invasive operation at minimal cost. Financial pressures are likely to discourage the performance of endoscopic, minimally invasive operations worldwide, especially in developing countries. Gasless operations like PLES are preferable, because they avoid risks of venous embolism, air embolism and venous thrombosis, which are actually rare, but can be lethal when they occur. Furthermore, gasless procedures might be beneficial for patients with low renal function, because there is a possibility that CO2 pressure might worsen renal function.13,14
The presented operation proceeds without the need to open the peritoneum. This might avoid raising the risk of postoperative intestinal obstruction, and might make the operation suitable for patients who have had past peritoneal surgery. Since the late 1990s, the retroperitoneal approach for laparoscopic radical nephrectomy has been initiated in several centers.3 In these centers, balloon dilation is usually used to create a retroperitoneal working space. However, in our experience, a large retroperitoneal working space is created through a minimum incision by dissecting along Gerota's fascia with standard instruments while observing it by combination of video image and direct vision. This method is likely to save the bag cost and avoid unnecessary bleeding associated with blind techniques. As previously reported, we believe that this operation would be especially suitable for chronic dialysis patients with renal cell carcinoma, who have a high risk of perioperative complications.9
Limitations of PLES include a relatively narrow working space and the requirement of more operative staff, including at least three surgeons. This limitation is being improved with the introduction of an endoscope holder or new retractors.
Compared with the standard open radical nephrectomy, many surgeons have reported that hand-assisted or pure laparoscopic radical nephrectomies are more beneficial to their patients.3–7 In the present study, magnification provided by the endoscope allowed easy identification of tissue planes and, therefore, permitted more precise dissection with minimal tissue trauma. In addition, the monitor screens provided detailed information on the operating procedure to anesthesiologists and nurses, as well as the operators. These benefits are likely to result in a more efficient procedure and fewer complications. PLES is a kind of modification of standard open surgery; the anatomic frame of reference, landmarks and operative techniques are similar in both operations. Therefore, the presented procedure might allow urologists with a traditionally trained background to perform a minimally invasive operation without laparoscopic technology, although it is helpful.
The long hospital stay reported from Japanese centers, including ours, might be due in part to the Japanese insurance system. In the present study, many patients, especially persons of advanced age, chose to stay extra days in our national hospital, against our recommendation of discharge. The day of discharge for a patient must be considered on a case-by-case basis, ensuring the best interests of the patient. In the present study, in most cases, the postoperative period until the patient could walk long distances, was free of a drainage tube, had full diet and did not need analgesics was much shorter than the actual number of days until the patient was discharged (Table 2). Compared with the postoperative results of our open radical nephrectomy, which was performed before PLES, PLES showed better results.15 For example, results from open surgery showed ‘days to oral feeding’ at 3.4 ± 1.2 days by transabdominal approach and 1.9 ± 0.7 days by translumbar approach; ‘days to walking’ results were 3.9 ± 1.1 days by transabdominal approach and 2.6 ± 0.6 days by translumbar approach.
In conclusion, the presented portless endoscopic radical nephrectomy minimizes morbidity while decreasing equipment costs, wound size and number, and risks of embolism and intestinal obstruction. This technique provides a clear alternative to standard open, hand-assisted laparoscopic or laparoscopic radical nephrectomy.