A Comparative Study of Laparoendoscopic Single-Site Surgery Versus Conventional Laparoscopy for Upper Urinary Tract Malignancies

During the last 10 years, the transition from conventional laparoscopy (CL) to laparoendoscopic single-site surgery (LESS) as a step toward scar-free surgery may represent a paradigm shift in reconstructive and extirpative surgeries in many surgical fields. To overcome the several limitations of CL (e.g., bleeding, hernias, internal organ damage, and undesirable cosmetic effects) that can occur at working ports with CL approaches, LESS for minimally invasive surgery has been the focus of numerous investigations. Consequently, the use of LESS in urology has increased substantially with the refinement of laparoscopic instruments [1-6].

However, although many studies have already demonstrated the safety and feasibility of LESS for almost all types of urological surgeries [1, 6-11], and some comparative studies have suggested that LESS is comparable with CL, the clinical advantage of LESS over CL in urology is still under debate, especially for malignant diseases [12, 13]. Thus, the current study was designed to compare the perioperative outcomes between LESS and CL for upper urinary tract malignancies.

For all three types of surgery, there were no significant differences in median age, sex, body mass index, abdominopelvic operation history, or site of operation between the two groups (radical nephrectomy: p=0.52, p=0.33, p=0.55, p=0.74 and p=0.75; nephroureterectomy with bladder cuff excision: p=0.35, p=0.54, p=0.94, p=1.00, and p=1.00; partial nephrectomy: p=0.51, p=0.31, p=1.00, p=0.43, and p=1.00 respectively) (Table 1).

The pathologic results of three surgeries are summarized in Table 2. For radical nephrectomy, T stage was widely distributed from pT1 to pT3. The same result was found for nephroureterectomy with bladder cuff excision. However, partial nephrectomy was performed in patients whose pathologic result was pT1. Regardless of surgery type, only one case of a positive surgical margin was found in a patient who underwent partial nephrectomy by CL. In nephroureterectomy with bladder cuff excision cases, no positive bladder cuff excision margins were found in either the LESS or the CL group (Fig. 1).

FIG. 1
Gross pathologic image of laparoendoscopic single-site surgery nephroureterectomy with bladder cuff excision. Final pathologic result: high-grade transitional cell carcinoma, pT3, located at the right lower ureter with a negative bladder cuff excision margin.

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TABLE 2
Pathologic results of surgeries for upper urinary tract malignancies

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In total, there were no grade IV, V Clavien-Dindo classifications in any of the laparoscopic surgeries and no port-related morbidity in any CL cases [16]. Moreover, no instances of emergency care or readmission after discharge occurred, regardless of surgery type.

In the radical nephrectomy cases, no significant differences in OPT, EBL, transfusion rate, LHS, or VAS pain score were found between the two groups (p=0.62, p=0.71, p=0.22, p=0.23, and p=0.08, respectively), but the complication rate was greater in the LESS group than in the CL group. These complications occurred in some (<10) of the earlier cases, but were eliminated after the surgeons became more experienced (Table 3).

TABLE 3
Perioperative outcomes of CL and LESS for upper urinary tract malignancies

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In the nephroureterectomy with bladder cuff excision cases, no significant differences in OPT, EBL, LHS, or VAS pain score were found between the two groups (p=0.10, p=0.64, p=0.81, and p=0.25, respectively). Moreover, no transfusions were needed and no complications occurred in either group (Table 3).

In the partial nephrectomy cases, no significant differences in OPT, EBL, ischemic time, LHS, or VAS pain score were found between the two groups (p=0.27, p=0.13, p=0.581, p=0.93, and p=0.19, respectively), but the complication rate was greater in the LESS group than in the CL group. Furthermore, transfusions occurred in three cases in the CL group (Table 3).

For the past several years, LESS has been used in various types of urologic surgeries, and many studies of the safety and feasibility of LESS have been conducted. However, few comparative studies between LESS and other surgical modalities have been conducted, especially for the malignant diseases [2, 6, 14].

Several comparative studies of radical nephrectomy have shown no differences in mean OPT, LHS, complications rates, or the use of analgesics between CL and LESS patients [10, 17, 18]. Moreover, Park et al. [9] reported that radical nephrectomy with LESS is as safe and effective as radical nephrectomy and is associated with less postoperative pain and shorter hospital stays. In our study, although no significant differences in OPT, EBL, transfusion rates, VAS pain score, or LHS were found between the LESS and CL groups for all three surgery types, more complications occurred in the LESS radical nephrectomy group than in the CL radical nephrectomy group. However, because most of the complications with LESS radical nephrectomy occurred in the early introductory period of the procedure, we expect that the complication rates with LESS and CL will cease to be significantly different as surgeons gain more experience.

In the case of partial nephrectomy, more complications occurred with LESS (3/5) than with CL (0/16) in our study. Other studies of partial nephrectomy with LESS showed various complication rates. Irwin et al reported complications in 37.5% (3/8) of cases of partial nephrectomy with LESS [19]. Desai et al. [2] reported 1 complication among 6 patients who underwent partial nephrectomy with LESS. Only five patients at our institution have undergone partial nephrectomy with LESS; therefore, we expect that the incidence of complications will decrease as our surgeons gain more experience. However, given the current level of experience with the LESS techniques, we suggest that partial nephrectomy with LESS be performed restrictively.

Some studies of nephroureterectomy with bladder cuff excision with LESS have shown it to be safe and feasible [20, 21]. However, few studies have compared LESS with CL. In our studies, no statistically significant differences in perioperative outcomes were found between nephroureterectomy with LESS and nephroureterectomy with CL, even though the VAS pain scores were higher in the LESS group than in the CL group until the second postoperative day. These higher VAS pain scores in the LESS group may have been related to longer OPTs in the LESS group, especially because of difficulties with bladder cuff excision and bladder repair. However, as surgeons gain more experience, these difficulties will be overcome. If surgery can be conducted and completed through a single, small incision while remaining true to oncological principles and without serious complications (as occurred in our nephroureterectomy cases with LESS), especially for extirpative cases, patients will undoubtedly benefit. Therefore, we suggest that nephroureterectomy with bladder cuff excision with LESS may be used for malignant cases, for which the benefits of LESS could be maximized despite the small number of patients in our study.

There is no doubt that LESS is more technically challenging than CL. Thus, it may not share the broad applicability of CL for complex procedures, although this may change as the technique matures and with robotic innovations in LESS. Therefore, notwithstanding the major limitations of the current study, including the retrospective design and small number of patients, we suggest that LESS should be used selectively and mainly for radical nephrectomy and nephroureterectomy with bladder cuff excision, We also believe that LESS is a very attractive surgical technique, and the benefits of LESS could be maximized in cases requiring extirpative procedures.

A prospective randomized control trial remains the ideal way to assess new surgical innovations; however, it is difficult to use such an approach in actual patients in a clinical setting, as in robot-assisted laparoscopic prostatectomy versus open prostatectomy. Therefore, a practical, well-designed multicenter observational study including more urologic surgeries would provide the necessary guidance to assess the proper role for LESS.

Perioperative outcomes for radical nephrectomy and nephroureterectomy with bladder cuff excision with LESS were not statistically different from those with the CL approach. Therefore, the use of LESS in these cases is expected to expand as surgeons gain more experience with this technique and as further technical advances in laparoscopic instruments occur. However, partial nephrectomy with LESS should be performed restrictively considering the current level of surgical skills.