The standard treatment for UTUC has traditionally consisted of open nephroureterectomy with excision of a bladder cuff. With technical improvements, LNU has been applied to patients extensively since the first case presented by CLAYMAN[5]. A serious of studies have shown that LNU has similar oncologic outcomes compared to the open technique[6–8]. The standard LNU, which was used in most of centers, was divided into two steps. After retroperitoneal laparoscopic nephrectomy, the distal ureter with a cuff of bladder was excised through a lower-abdominal incision when patients’ position was needed to be changed. Besides of time consuming, large injure and more blood loss, the ureteric orifice was always difficult to be removed completely because of its deep position.
The CRT technique we present here, which combines the advantages of both retroperitoneal (easy to mobilize and handle the renal pedicle) and transperitoneal (easy recognition of anatomic landmarks and large working space) approaches, has the following numerous advantages.
More extensive surgical indications. Besides UTUC and renal tuberculosis, duplication of kidney and ureter is very suitable for CRT technique. As very close to upper pole ureter and its deep anatomical position, the lower pole moiety can be easily injured inadvertently in open surgery, which will be preserved well in laparoscopic surgery. Patients with the history of ipsilateral herniorrhaphy or renal transplantation may not be good candidates for a second hypogastric open surgery, but it will be managed successfully with CRT technique. In the current study, two patients with the history of ipsilateral herniorrhaphy or renal transplantation accepted CRT LNU respectively, and got good postoperative recovery.
Shorter operation time and less blood loss. Homayoun et al.[9] reported a simplified approach of transperitoneal robot-assisted nephroureterectomy, which requiring no patient repositioning or robot redocking. Their mean operation time and median EBL was 300 minutes and 200 ml. The reasons for less operation time of CRT technique are as follows: Firstly, It’s more convenient and time saving to manage renal pedicle and nephrectomy through retroperitoneal approach, which takes 30 to 55 minutes generally; Secondly, The surgeon can choose the best angle to get the most sufficient exposure through moving camera among trocars; Thirdly, avoiding patients’ repositioning, once more sterilization and draping during operation can save an amount of time. Fourthly, it is time saving for closing a smaller incision, which takes about 20 minutes in CRT group.
More minimally invasion and enhanced recovery. Compared to standard technique, CRT technique has shorter incision length, less painful, less time of surgical drains and less hospital stay after surgery. Three patients experienced incision fat liquefaction resulted from long operation and retractor time in standard group, which need much more time of wound caring.
Lower incidence of postoperative abdomen bulge or incisional hernia. In addition to the commonly recognized factors such as incision infection, old age, and high BMI, many studies have shown that the injury of muscle and neurovascular bundle (NVB) were significant risk factors for the occurrence of postoperative abdomen bulge or incisional hernia[10, 11]. Some studies have also reported that increased incision length, prolonged operation time and long-term using of retractors during surgery were statistically significant factors in the development of incisional hernia[12, 13]. In the present study, the incidence of postoperative abdomen bulge or incisional hernia in CRT group was less than that in standard group, the reasons may be related to the above factors.
Better oncological outcomes. Although no significant difference was detected in the disease free survival (DFS) between the two groups, CRT technique has more appropriate angle and space to achieve completely resection of distal ureter and bladder cuff. In the present study, there were three cases suffering local recurrence in standard group, while no recurrence in CRT group. With the time extending, there may be significant survival benefits in patients with CRT technique.
Additionally, compared to standard technique, which needs at least three to four staffs, two or three staffs are enough for CRT technique.
There were several limitations in this study. First, it was a non-randomized retrospective study, and limitations may have existed in the study design account for selection bias. Second, the sample size was not large enough to make the convincing conclusion. Third, the follow-up period of our study was too short to obtain more significant differences between the two groups, especially in oncological outcomes. More large-sample and high-quality RCTs are needed to confirm these preliminary findings.