Robotic urologic surgery using the KangDuo-Surgical Robot-01 system: A single-center prospective analysis.

The introduction of robotic assistance in laparoscopic surgery is a milestone in the history of minimally invasive surgery, and it overcame the technical limitations of laparoscopic surgery, such as unsatisfactory flexibility and a long learning curve. [ 1 ] The da Vinci surgical system is the most successful surgical robot worldwide, dominating the market for over 20 years, since the United States Food and Drug Administration approved its use for humans in 2000. The da Vinci surgical system is increasingly used in kidney, bladder and prostate surgery and reconstructive urology due to its advantages of magnified stereoscopic vision, tremor filtration, enhanced accuracy and high dexterity. [ 2 , 3 ] However, it is not available in many hospitals, particularly in developing countries such as China, because of the high equipment and maintenance costs. In recent years, an increasing number of newly developed robotic surgical systems have entered the market, such as the Revo-I, [ 4 , 5 ] Senhance [ 6 , 7 ] and Versius systems. [ 8 ] Recently, a new surgical robot, the KangDuo-Surgical Robot-01 (KD-SR-01) system (Suzhou KangDuo Robot Co., Ltd., Suzhou, China) was developed in China. This robot system is a master–slave system and consists of an open surgeon console, a three-arm robotic operation cart, and a vision cart [Supplementary Figure 1, http://links.lww.com/CM9/B796 ]. The surgeon console has two monitors. The lower one displays intraoperative three-dimensional (3D) images, and the upper one allows external access to navigation or auxiliary images, such as 3D reconstruction models based on preoperative computerized tomography images [Supplementary Figure 2, http://links.lww.com/CM9/B796 ]. The open console design allows the surgeons to keep their neck upright to avoid neck fatigue [Supplementary Figure 1, http://links.lww.com/CM9/B796 ]. A preclinical animal study with live porcine models showed that the KD-SR-01 system was feasible and safe for partial nephrectomy (PN). [ 9 ] The KD-SR-01 system showed no significant difference in surgical outcomes compared to 3D laparoscopic surgery, but it had advantages in terms of ergonomics. [ 9 ] In previous small clinical cohort studies, we found that this platform was feasible and safe for dismembered pyeloplasty, [ 10 ] retroperitoneal PN, [ 11 ] and extraperitoneal radical prostatectomy (RP). [ 12 ] In this study, we aimed to evaluate the feasibility, safety, and effectiveness of the KD-SR-01 system for most urologic procedures, based on our single-center experience.

None.

From August 2020 to April 2023, consecutive urological procedures were performed using the KD-SR-01 system at our center. The procedures included PN, upper and lower urinary tract reconstruction and RP. The clinical data of these patients were prospectively collected. Subjects aged 18–75 years of either sex (male or female), requiring surgical treatment, were included. Indications for surgical treatment of upper urinary tract (UUT) obstruction included the presence of recurrent flank pain, radiographical mechanical urinary obstruction, evident hydronephrosis, and renal function deterioration. Patients with renal tumors meeting the criteria of R.E.N.A.L. (radius, exophytic/endophytic, nearness, anterior/posterior, location) nephrometry scores ≤9 and the T1a clinical stages were included. In addition, patients with prostate cancer confirmed through biopsy and elevated serum prostate-specific antigen levels were included. All patients with prostate cancer and renal tumors had clinically localized disease without evidence of distant metastases, as determined by preoperative imaging. Patients who were unable to tolerate surgery due to coagulation dysfunction, uncontrolled infection, pregnancy, or lactation were excluded. All patients were informed of the risks related to robotic surgeries performed by the KD-SR-01 system, and then they signed the informed consent form. This study was approved by the Medical Ethics Committee of Peking University First Hospital (No. 2020Yan174). Data collection and analysis were performed in compliance with the Declaration of Helsinki . [ 13 ] All procedures were performed by two surgeons (Xuesong Li and Cheng Shen) who had experience performing more than 100 robotic surgeries using the da Vinci surgical system. For renal tumors, transperitoneal PN was performed for anterior or hilar tumors, while retroperitoneal PN was performed for posterior or lateral tumors. The trocar layout and surgical procedures were similar to those previously reported. [ 11 , 14 ] For patients with ureteropelvic junction obstruction, a modified robotic dismembered pyeloplasty through a transperitoneal approach was performed, which was reported in our previous study. [ 15 ] For concomitant renal stones, lithotomy using flexible cystoscopy was performed through the trocar tract. For proximal and midureteral strictures, ureterourerostomy or lingual mucosal onlay ureteroplasty was performed according to the length of the ureteral stricture. The procedures of lingual mucosal graft harvest and the posteriorly augmented anastomotic technique were described in our previous study. [ 16 ] For congenital distal ureteral obstruction, or complex iatrogenic distal ureteral injury, ureterovesical reimplantation (UR) together with the psoas hitch technique was performed, which involved fixing the bladder wall to the ipsilateral psoas muscle. [ 17 ] If the ureteral stricture is too long to achieve a tension-free anastomosis, an additional Boari-flap technique may be needed. To avoid vesicoureteral reflux, a “ureteral nipple” or “bladder submucosal tunnel” technique may be considered. The above reconstruction techniques are detailed in previous reports. [ 18 ] The RP procedures were performed via the extraperitoneal or the intraperitoneal approach. For extraperitoneal RP, the patient was placed in the Trendelenburg position, and five ports were placed with one for the robotic camera, two for the robotic arms and two for the assistant. The port placement and surgical procedures have been shown in detail in our previous study. [ 12 ] Additionally, for the intraperitoneal approach, the patient was placed in the lithotomy position first, and then the pneumoperitoneum was established, and the five ports were placed. Then, the operating table was moved into the steep Trendelenburg position after a Foley catheter was inserted. The extraperitoneal space for prostate surgery was entered through an inverted U-shaped incision in the peritoneum, between the medial umbilical ligaments and superior to the dome of the bladder. The incisions were deepened and joined anteriorly; the bladder was separated from the anterior abdominal wall, and then the space of Retzius was entered. Bilateral pelvic lymphadenectomy is needed for patients with a Gleason score of 8 or 9. The bladder neck was dissected in an antegrade fashion using electrocautery. The vas deferens and seminal vesicles were resected after the anterior Denonvilliers fascia was incised. For nerve sparing, the prostate pedicles and the neurovascular bundle were separated from the prostate posterolaterally using scissors or bipolar coagulation. After the prostatic apex was fully exposed and the dorsal venous complex was controlled, the urethra was transected distal to the prostatic notch. Finally, the urethrovesical anastomosis was completed using two barbed sutures in a running fashion. The procedures have been described in detail in previous studies. [ 19 , 20 ] The clinical features, perioperative outcomes, and follow-up outcomes were collected prospectively. Clinical features included demographic data and disease features. Perioperative outcomes consisted of the operation time, intraoperative blood loss, conversion rate, length of hospital stay and operative complications. Intraoperative and postoperative complications were prospectively recorded and graded according to the Clavien–Dindo classification. [ 21 ] Follow-up assessments included pathology examination, postoperative imaging, and functional evaluations. The primary criterion for surgical success was the completion of procedures without conversion to laparoscopic or open surgery. For PN, a warm ischemia time (WIT) of less than 30 min and negative surgical margins were needed. Moreover, the subjective success of UUT reconstruction was based on symptom relief, while the objective success was defined as achieving stable or improved renal function and a reduction of hydronephrosis observed on imaging. All statistical analyses were performed using SPSS 25.0 (IBM Corporation, Armonk, NY, USA). Categorical variables were presented using frequencies ( n ) and frequencies (%), and chi-squared tests were used to compare the differences between PN via the different surgical approaches and RP via the different surgical approaches. Continuous variables were presented as the mean ± standard deviation for normally distributed variables, and as medians and ranges for non-normally distributed variables. The Mann–Whitney U test or Fisher’s exact test was used to compare the differences between PN via the different surgical approaches and RP via the different surgical approaches. A two-sided P -value <0.05 was deemed statistically significant.

During this period, a total of 110 consecutive patients were enrolled, with 72 male patients. The patients had a median age of 53 (range: 16–75) years and a median body mass index of 24.6 (range: 15.2–32.9) kg/m 2 . The performed surgeries consisted of procedures involving both the UUT (57/110, 51.8%) and the lower urinary tract (53/110, 48.2%). Within the UUT surgeries, there were 28 cases of PN, 26 cases of pyeloplasty, 1 case of lingual mucosal graft ureteroplasty, and 2 cases of ureteroureterostomy. Notably, 17 patients underwent PN using the transperitoneal approach, while 11 patients underwent PN using the retroperitoneal approach. Lower urinary tract procedures consisted of 12 cases of UR and 41 cases of RP. The etiology and surgical data of the above procedures are shown in Table  1 . The median operative time for PN was 112.5 (range: 75.0–192.0) min, 157.0 (range: 110.0–300.0) min for pyeloplasty, 142.5 (range: 107.0–185.0) min for UR, and 138.0 (range: 107.0–197.0) min for RP. The median intraoperative blood loss was 10 (range: 0–450) mL, 10 (range: 5–100) mL for pyeloplasty, 20 (range: 0–150) mL for UR, and 50 (range: 10–200) mL for RP. Moreover, concomitant procedures including lithotomy or lithotripsy ( n = 4), bilateral oophorocystectomy ( n = 1), uterine adnexectomy ( n = 1), and pelvic endometriosis resection ( n = 1) were performed together. All procedures were successfully completed without conversion to traditional laparoscopic or open surgery, and none of the patients received intraoperative blood transfusion. No major complications (Clavien–Dindo grade ≥III) were observed in any of the urological procedures. The types of complications and their managements are summarized in Supplementary Table 1, http://links.lww.com/CM9/B796 . Etiology and surgical data of the 110 enrolled patients underwent robotic urologic surgery. Data are presented as n (%) or median (range). * The Clavien-Dindo grades for complications observed in all patients were less than grade III. The median WIT of the patients who underwent PN was 17.3 (range: 7.1–29.2) min. Two patients who experienced abdominal pain and toothache after the operation were treated with analgesics [Supplementary Table 1, http://links.lww.com/CM9/B796 ]. Additionally, we compared the clinical, perioperative, and follow-up data between intraperitoneal and retroperitoneal PN. However, there were no statistically significant differences between the two groups [Table  2 ]. Postoperative ultrasound examinations revealed no abnormalities in renal blood supply or morphological atrophy in all patients. There was no significant change in the estimated glomerular filtration rate, and no evidence of local tumor recurrence, or distant metastasis at the median follow-up of 26.0 (range: 24.0–27.0) months after surgery. Comparison of the clinical data and surgical outcomes between intraperitoneal and retroperitoneal partial nephrectomy by using the KD-SR-01 system. Data are presented as n/n , n (%) or median (range). * Z values; † χ 2 values. ΔeGFR represents the difference between eGFR 6 months post-surgery and the preoperative eGFR. NA: Not applicable; eGFR: Estimated glomerular filtration rate; R.E.N.A.L.: radius, exophytic/endophytic, nearness, anterior/posterior, location. In all patients who underwent UUT reconstruction, ureteral stents were successfully removed two months after surgery. During the median follow-up of 29.5 (range: 3.5–32.0) months, only one patient who underwent pyeloplasty complained of recurrent flank pain 17 months after surgery, and postoperative imaging also showed unchanged hydronephrosis. All other patients maintained stable renal function, and their preoperative symptoms were alleviated or resolved after surgery. The overall subjective success rate of pyeloplasty was 96% (25/26). A patient who underwent UR presented with recurrent hydronephrosis and lumbago 11 months after surgery and was treated with balloon dilation. Pelvic lymph node dissection was performed in 11 patients who underwent intraperitoneal RP, and postoperative pathological results showed that one patient had lymph node metastasis. The overall positive surgical margin (PSM) rate was 39% (16/41). The PSM rate of intraperitoneal RP was 48% (12/25), and that of extraperitoneal RP was 25% (4/16). The rate of urinary continence recovery at one month after catheter removal was 88% (36/41). No biochemical recurrence was observed in any patient during the median follow-up of 11.0 (range: 3.0–22.0) months. Additionally, a comparative analysis of RP via the extraperitoneal or the intraperitoneal approach using the KD-SR-01 system showed no statistically significant difference in the preoperative volume of the prostate, biopsy Gleason score, intraoperative blood loss, PSM rate, or the rates of urinary continence recovery at one month after catheter removal [Table  3 ]. However, patients who underwent intraperitoneal RP had higher preoperative prostate-specific antigen levels ( Z = –2.292, P = 0.021) and longer operative times ( Z = –1.992, P = 0.046). Comparison of the clinical data and surgical outcomes between extraperitoneal and intraperitoneal radical prostatectomy by using the KD-SR-01 system. Data are presented as n (%) or median (range). * Z values; † χ 2 values. NA: Not applicable.

Surgical robots have revolutionized the field of urological procedures, contributing to the increased applicability and precision of laparoscopic surgeries. [ 3 ] The KD-SR-01 system is a surgical robot that was recently developed in China. Its successful preclinical outcomes enabled us to perform a larger number of complex urological procedures in our center. [ 9 ] The present study, involving a larger sample size, provides additional evidence supporting the feasibility and effectiveness of the KD-SR-01 system in various urological procedures, as indicated by the mid-term outcomes. For the sake of surgical safety, we enrolled patients with stage T1a renal tumors and R.E.N.A.L. nephrometry scores ≤9. [ 22 , 23 ] In our study, the WIT of PN ranged from 7.1 min to 29.2 min, which were less than 30 min. The overall complication rate was 11% (3/28), with no high-grade complications. No abnormal renal blood supply or morphological atrophy, or stable renal function, was observed in any patient at the last follow-up. Ficarra et al [ 24 ] reported that the median WIT of patients treated with the da Vinci surgical system was only 18.0 min, and the overall complication rate was as low as 12.0%, with 3.0% high-grade complications. In addition, Dulabon et al [ 25 ] analyzed a large multicenter series of PN performed with the da Vinci surgical system. The mean WIT of nonhilar tumors was 19.6 min, and there was a low risk of complications (2.4% of low-grade complications). The above evidence proved the feasibility and efficacy of both transperitoneal and retroperitoneal PN with the KD-SR-01 system. For procedures of urinary tract reconstruction, surgical success is usually defined as resolution of preoperative symptoms, stable or improved postoperative renal function, and objective improvement on postoperative imaging. [ 26 ] In our study, the median operative time for pyeloplasty was 157.0 (range: 110.0–300.0) min, and the overall complication rate was 12% (3/26). Only one patient complained of reoccurring flank pain and showed unchanged hydronephrosis, and the overall surgical success rate was 96% (25/26) during the median follow-up of 29.5 months. Marien et al [ 26 ] reported their single-center experience of 149 patients who underwent pyeloplasty with the da Vinci surgical system. The mean operative time was 185.2 min, and perioperative complications were observed in 16 patients (10.7%), 13 (8.7%) of whom had a high Clavien–Dindo grade. The radiographic and symptomatic success rates were 99.0% and 95.0%, respectively. [ 26 ] Thus, in pyeloplasty, the KD-SR-01 system has similar surgical feasibility and efficacy as the da Vinci surgical system. For RP, our median operative time was shorter than that of the da Vinci surgical system (179.0 min), and our median intraoperative blood loss was less than that of the da Vinci surgical system (191 mL), as reported by De Carlo et al [ 27 ] . The overall complication rate was 11% (4/36), which is lower than that of the da Vinci surgical system (18.5%), as shown by De Carlo et al [ 27 ] . In our study, 39% (16/41) of patients had PSM, of whom 47% were in the pT2 stage and 50% were in the pT3 stage. Moreover, the PSM rate in the intraperitoneal RP group was 48% (12/25), and that in the extraperitoneal RP group was 25% (4/16). Previous investigators reported a PSM rate of 10.4%–38.0% after da Vinci robot assisted RP. [ 28 , 29 ] Venckus et al [ 6 ] reported a PSM rate of 33.9% (43/127) in patients who underwent RP usingthe Senhance robotic system. Similarly, Kulis et al [ 30 ] demonstrated that the PSM rate was 28.0% (30/107) in patients undergoing extraperitoneal RP using the Senhance robotic system. Our PSM rate, especially for the intraperitoneal approach, was higher than that of the da Vinci surgical system and the Senhance robotic system, however, no biochemical recurrence occurred in any patient until the last follow-up. In our study, there were patients with more complex cases that had a higher clinical T stage and higher Gleason score, especially one patient with a pathological stage of T4, which may be related to the high rate of PSM. We insist that by performing more surgeries and gaining surgical experience, we will reduce the PSM rate. Unlike the immersive surgeon console of the da Vinci surgical system, our KD-SR-01 system has an open surgeon console. The open console allows the surgeons to keep their neck upright to avoid neck fatigue and ensure optimized hand–eye coordination. [ 11 , 12 ] This design of the surgeon console is similar to that of the Senhance surgical system and the micro hand S surgical robot (another surgical robot developed in China). Yao et al [ 31 ] reported a consecutive case series of 86 patients in general surgery using the micro hand S surgical robot. However, there have been few articles describing the application of the micro hand S surgical robot in urological procedures. Previous case series reports on the Senhance surgical system have mainly focused on abdominal and gynecological surgeries, [ 7 , 32 ] and although several articles described urological procedures, most were RP. [ 6 , 30 ] The surgical experiences of novel robotic platforms in the field of urology according to previous studies are summarized in Supplementary Table 2, http://links.lww.com/CM9/B796 . Recently, we compared the efficacy and safety of pyeloplasty [ 33 ] and RP [ 34 ] performed using the KD-SR system and the da Vinci Si system in small retrospective cohorts. The results indicated that the KD-SR-01 system had similar surgical outcomes to the da Vinci system, except for a longer operation time. However, studies with larger sample sizes and multicenter randomized controlled trials are needed to further evaluate the KD-SR system. Recently, Coussons et al [ 35 ] compared the costs of laparoscopic, Senhance and da Vinci hysterectomies, and found that Senhance hysterectomies had lower median instrument costs than the da Vinci surgical system ($559 vs. $1393 respectively, P <0.001). However, there was no statistically significant difference in the cost between Senhance and laparoscopic hysterectomies ( P = 0.336). The reason for the high surgical cost of the da Vinci surgical system is primarily related to the robot costs. The KD-SR-01 system is completely self-developed and had many original technical achievements. The development and manufacturing cost of the KD-SR-01 system is approximately 25%–30% of that of the da Vinci robotic system. Surgeries using the KD-SR-01 system were free for all patients in our study, and we believe its instrument and maintenance costs would be far less than those of the da Vinci surgical system. It is noteworthy to mention that the KD-SR-01 system was approved by the National Medical Products Administration to enter the Chinese market on June 24, 2022, which will be helpful for promoting the wide use of the KD-SR-01 system in Chinese hospitals. The disadvantages of the KD-SR-01 system are lack of tactile feedback and limited movement, which can increase uncertainty and risk in the surgery. Furthermore, our study also has several limitations. First, this was a single-center single-arm study, and future multicenter randomized controlled trials comparing traditional laparoscopy and the da Vinci surgical system are needed to further evaluate this platform. Second, studies with long-term oncologic and functional results are also necessary. In conclusion, according to our single center experience and the mid-term outcomes, robotic urologic surgeries using the KD-SR-01 system are feasible, safe, and effective. Studies with larger sample sizes and longer follow-ups and multicenter randomized controlled trials are needed to further evaluate this platform.

None.

The authors thank all the staff of the operating room at Peking University First Hospital for their valuable contributions to this study.