Robotic urologic surgery using the Toumai MT-1000 Endoscopic Surgical System: a single-center prospective analysis

Introduction

In the evolution of modern medical technology, robot-assisted surgery represents a revolutionary advancement. In the field of urology, robot-assisted laparoscopic procedures have become a mainstream practice. The development of advanced technology and its clinical applications are closely intertwined and mutually influential. Despite the dominance of the Da Vinci surgical robot for nearly two decades, the widespread adoption of robotic surgery in developing regions, including China, Asia, Africa, and Latin America, has been constrained by high initial costs and regulatory challenges (1-3). Consequently, robotic systems with Chinese intellectual property rights are currently undergoing continued development and clinical trials (4).

This study features the Toumai MT-1000 Endoscopic Surgical System, a state-of-the-art surgical robot independently developed in China. The Toumai MT-1000 includes several key components: four robotic arms, a stereoscopic view providing an immersive Naked Eye 3 dimensions (3D) experience for surgeons, and simulators. It also boasts several core features, including Picture-in-Picture, Dual-Console functionality, one-click Expand/Collapse, Compliance Control, image resolution of 1,920×1,080 at 60 Hz, and a master operating force of ≤0.1 N. Notably, the Toumai MT-1000 has achieved leading-edge techniques such as Force Perception, 5G Remote Operation, and a master-slave delay of ≤70 ms, which are not yet widely implemented in other robotic systems.

This study aims to assess the feasibility, safety, and effectiveness of the Toumai MT-1000 system for a variety of urological procedures, based on our single-center experience. We present this article in accordance with the STROBE reporting checklist (available at https://tau.amegroups.com/article/view/10.21037/tau-24-451/rc).

Methods

Patient selection and information

From October 2023 to January 2024, 20 urological procedures were performed using the Toumai MT-1000 system at our center. These included five partial nephrectomies, five adrenalectomies, five upper urinary tract (UUT) reconstructions, four radical prostatectomies (RPs), and one radical cystectomy (RC). Clinical data were prospectively collected.

Inclusion criteria: patients aged 18–75 years, of any gender, requiring surgical treatment were included. Indications for UUT obstruction included recurrent flank pain, radiographic evidence of obstruction, hydronephrosis, and renal function decline. Renal tumors were included if they met the Radius, Exophytic/Endophytic, Nearness, Anterior/posterior, Location (R.E.N.A.L.) nephrometry score ≤9 and clinical stage T1. Prostate cancer cases confirmed by biopsy with elevated PSA levels and muscle-invasive bladder cancer confirmed by biopsy and imaging were included. Non-pheochromocytoma adrenal masses and small cortical adenomas were also eligible. A patient with preoperative imaging of T3 stage bladder cancer was included for RC. All cancer cases were clinically localized by preoperative imaging.

Exclusion criteria: patients were excluded if they had coagulation dysfunction, uncontrolled infection, were pregnant or lactating, or unable to tolerate surgery.

All patients were informed of the enrolment and risks associated with the Toumai MT-1000 robotic surgeries and provided written consent. The study was approved by the Medical Ethics Committee of Peking University First Hospital Miyun Hospital (No. 2023Yan016-001). The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013).

Surgical technique

All surgeries were carried out by two experienced surgeons (X.L. and Z.Z.), each having performed over 100 robotic surgeries utilizing the da Vinci system. For renal neoplasms, anterior or hilar tumors underwent transperitoneal partial nephrectomy (PN), while retroperitoneal PN was opted for posterior or dorsal tumors, with all procedures conducted under on-clamp conditions. Adrenal masses were addressed through a transperitoneal adrenalectomy. The trocar placement and surgical techniques mirrored previously documented methods (5). For patients presenting with ureteropelvic junction obstruction, a modified robotic dismembered pyeloplasty via a transperitoneal approach was utilized, as detailed in our prior publication (6). For proximal and mid-ureteral strictures, either ureteroureterostomy or lingual mucosal onlay ureteroplasty was performed, depending on the stricture’s length, with graft harvesting and posterior anastomosis techniques outlined in earlier research (7). In cases of congenital or complex iatrogenic distal ureteral obstruction, ureterovesical reimplantation (UR) with a psoas hitch was employed to secure the bladder to the ipsilateral psoas muscle (8). RP and RC followed an intraperitoneal route (9). Patients were initially placed in the lithotomy position, pneumoperitoneum was then established, and five trocars were inserted. Subsequently, the table was tilted to a steep Trendelenburg position after catheter insertion. For patients with a Gleason score of 8 or 9, bilateral pelvic lymph node dissection was performed. The bladder neck was dissected in an antegrade fashion using electrocautery, with the vas deferens and seminal vesicles being excised following incision of the anterior Denonvilliers’ fascia.

Data collection

The clinical features, perioperative outcomes, and follow-up results were collected prospectively. Clinical features included demographic and disease characteristics. Perioperative outcomes comprised operation time, intraoperative blood loss, conversion rates, hospital stay length, and operative complications. Complications were recorded and graded using the Clavien-Dindo classification (10).

Follow-up included pathological analysis, imaging, and functional tests. Surgical success was defined as completing the procedure without needing conversion to laparoscopic or open surgery. For PN, success was based on keeping warm ischemia time (WIT) under 30 min and achieving clear surgical margins. The success of UUT reconstruction was assessed by symptom relief and improvements in renal function and hydronephrosis, as seen in imaging. For RC and RP, success was determined by completing the surgery without conversion to an open approach, achieving negative surgical margins, and maintaining perioperative safety without major complications (Clavien-Dindo grade III or higher). Adrenalectomy success was defined by complete tumor resection, minimal blood loss, and no requirement for intraoperative conversion or significant deviation from the planned procedure. Postoperative success across all procedures included the absence of major complications within 30 days and the attainment of targeted functional outcomes, such as organ function preservation and no need for early re-intervention.

Statistical analysis

Statistical analyses were conducted using WPS OFFICE 6.7 (Kingsoft Office Corporation, China). Categorical variables were presented as frequencies (n) and percentages (%), while continuous variables were shown as mean (range).

Results

In this study, we prospectively included 20 cases (Table 1): 15 UUT surgeries and 5 lower urinary tract surgeries. UUT surgeries comprised PN (n=5), adrenal mass excision (n=5), and upper tract reconstruction (n=5). Lower urinary tract surgeries included RP (n=4) and RC (n=1). The Toumai MT-1000 system was used for these procedures. In our center, the average docking time was 13.7 min (range, 3.0–35.0 min), with 5 out of 20 cases experiencing complications, all of which were postoperative fever. All patients were followed up for 3 months postoperatively. The surgical success rate, defined by the absence of conversion to other surgical methods (such as open surgery), was 100%.

In this study, five patients underwent PN (Table 2). The cohort consisted of one female and four males, with an average age of 44.4 years and a mean body mass index (BMI) of 27.4 kg/m². Among these, three procedures were performed on the left kidney and two on the right. The R.E.N.A.L. nephrometry score indicated four cases with low scores (4-6) and one case with a medium score (7-9). All RAPN procedures were performed under on-clamping conditions. The average WIT was 34.6 min, with an average docking time of 12.8 min and an average total operative time of 175.0 min. Of the five patients, four underwent the retroperitoneal approach, while one had the transperitoneal approach.

Postoperatively, the average hemoglobin drop was 1.2 g/dL, and the average length of hospital stay was 9.4 days. Two patients experienced complications, both of which were postoperative fever. All five patients were followed up for 3 months. Pathological analysis revealed four cases of clear cell carcinoma and one case of chromophobe cell carcinoma, all with negative surgical margins and staged as pT1. The average estimated glomerular filtration rate (eGFR) at 3 months post-surgery was 95.0 mL/min/1.73 m², slightly lower than the preoperative value of 109.9 mL/min/1.73 m².

Our study included five patients who underwent adrenalectomy (Table 3). The etiology was classified as functional mass in two patients and non-functional mass in three patients. Among the participants, 80% were female (n=4) and 20% male (n=1). The average age was 42.4 years, ranging from 21.0 to 59.0 years. The mean BMI was 22.5 kg/m² (range, 19.4–25.2 kg/m²). Regarding laterality, 40% had left adrenal involvement and 60% right. Comorbidities included hypertension and diabetes mellitus, each present in 40% of the patients. The average mass size was 3.5 cm (range, 1.0–4.8 cm). Preoperative eGFR was 107.5 mL/min/1.73 m² (range, 99.0–122.9 mL/min/1.73 m²). Surgical approaches were intraperitoneal (n=2) and retroperitoneal (n=3). Docking time averaged 8.0 min (range, 5.0–15.0 min), and the operation time was 167.4 min (range, 128.0–224.0 min). The mean hemoglobin drop was 1.3 g/dL (range, 0.2–2.8 g/dL). The average hospital stay was 12.3 days (range, 11.0–14.0 days), with no recorded complications. The follow-up period was 3 months, during which the success rate of surgery was 100% (n=5). Three months postoperatively, the eGFR was 100.8 mL/min/1.73 m² (range, 85.5–128.2 mL/min/1.73 m²). Postoperative catecholamine and its metabolite levels were all within the normal range.

In the study involving intraperitoneal UUT reconstruction, five patients were included (Table 4): four females and one male, with an average age of 31.2 years and a mean BMI of 22.5 kg/m². Among these patients, one underwent pyeloplasty for left hydronephrosis, two received ureteral reconstruction for left ureteral stenosis, and two had UR for left distal ureteral stenosis. Preoperatively, the average width of hydronephrosis detected by ultrasound was 2.7 cm. For these procedures, the average robot docking time was 8.8 min, the average operation duration was 224.2 min, the average hemoglobin drop was 1.2 g/dL, and the average hospital stay was 9.8 days. Postoperatively, two patients experienced complications, both presenting with fever. All patients were followed up for 3 months. The average eGFR at 3 months after surgery was 112.8 mL/min/1.73 m², which showed no significant change from the preoperative value of 112.6 mL/min/1.73 m².

In this study, a total of five patients underwent lower tract surgery, comprising four RPs and one RC (Table 5). Among the patients who underwent RP, the average age was 65 years, and the mean BMI was 28.4 kg/m². The preoperative prostate-specific antigen (PSA) level averaged 18.5 ng/mL, and the prostate volume was 34.4 mL. The biopsy Gleason score were distributed as follows: 25% had a score of 3+4, 50% had 4+3, and 25% had 4+4.

The average docking time for the robotic surgery was 6.8 min, while the operation duration averaged 300.3 min. Hemoglobin levels dropped by an average of 2.3 g/dL, and the average hospital stay was 13.8 days. Complications were observed in 25% of the patients, all of whom experienced postoperative fever. And 25% of patients had positive surgical margins. Pathological staging revealed that 25% of patients were classified as pT2b, 75% as pT2c, and none as pT3. Lymphatic metastasis was present in 25% of patients. No patients had gained urinary continence 1 month after catheter removal. The average postoperative PSA level at 3 months was 0.011 ng/mL.

The patient who underwent RC was male, aged 70 years, with a BMI of 28.1 kg/m². For this patient, the docking time was 10.0 min, and the operation lasted 374.0 min. The hemoglobin drop was minimal at 0.2 g/dL, and the hospital stay was 20.0 days. No complications occurred, and the follow-up period was also 3 months. The pathological T stage for this patient was pT3, with no lymphatic metastasis.

Discussion

In the rapidly evolving landscape of science and technology, surgical methods have undergone significant transformation. Two decades ago, laparoscopy was at the forefront; today, robotic surgery has taken center stage. The widespread adoption of Da Vinci robotic systems globally (11) and in China (12,13) has been supported by extensive clinical studies demonstrating the safety and efficacy of robot-assisted laparoscopic procedures. China has consistently advanced in technology, beginning research on domestic surgical robots over a decade ago. These efforts have culminated in the development of the Toumai MT-1000 Endoscopic Surgical System, a domestically developed robot with proprietary technology. This study represents its first global clinical trial, aiming to evaluate its safety and efficacy in urological surgery.

Key findings

This study represents the first formal global clinical trial of the Toumai MT-1000 Endoscopic Surgical System, focusing on urological procedures at Peking University First Hospital as a single-center investigation. The study enrolled 20 patients and covered a comprehensive range of urological laparoscopic surgeries, including both routine and high-difficulty procedures. Specifically, 15 UUT surgeries and 5 lower urinary tract surgeries were performed, each requiring distinct robotic configurations. The safety and efficacy of the system were thoroughly validated across both types of surgeries. All procedures were successfully completed with the Toumai MT-1000 Endoscopic Surgical System, with no conversions to alternative surgical techniques and achieving the intended surgical goals. Postoperative complications occurred in 25% of the patients, all classified as Clavien-Dindo grade I or II, indicating relatively minor issues. Renal function, assessed preoperatively and at three months post-surgery, showed no significant decline, supporting the system’s safety in protecting renal function.

As previously mentioned, the Toumai MT-1000 system presents itself as a cost-effective alternative to the Da Vinci robotic system. The initial acquisition cost of the Toumai MT-1000 is approximately 18 million RMB, which is a one-time payment that covers subsequent operational use and maintenance. In practice, hospitals in China that have adopted the Toumai system do not yet adhere to a standardized pricing model for procedures. In contrast, the costs associated with using the Da Vinci system are well-established nationwide. Depending on the specific operational expenditures at each hospital, the activation fee for the Toumai MT-1000 system can be reduced to 20–50% of the cost of the Da Vinci system. This significant reduction in operational expenses provides a notable financial advantage, making the Toumai MT-1000 an attractive option for both hospitals and patients, particularly in budget-constrained settings. The potential for widespread adoption of this system could enhance access to advanced robotic surgeries, offering greater affordability and extending benefits to a larger patient population.

Surgeons reported favorable experiences with the system’s unique features. The force perception capability, which addresses the absence of tactile feedback in previous robotic systems (14), provided valuable sensory feedback, enhancing both precision and safety during surgery. Additionally, the 5G Remote Operation feature, developed in the context of China’s 5G advancements, offers significant potential for remote surgeries, though further studies are required to confirm its safety and efficacy. To sum up, the Toumai MT-1000 Endoscopic Surgical System demonstrated effective performance and safety in major urological laparoscopic procedures, with its advanced features contributing to improved surgical precision and user experience.

Explanations of findings and limitations

While the introduction of new technology is always eye-catching, this study also reveals some issues. Although both surgeons are experienced urologists, the duration of the surgeries was notably longer compared to similar procedures reported in other studies (4). Specifically, the average WIT for PN was 34.6 min. Two main factors contributed to the extended operative times observed with the Toumai MT-1000 system. First, as a novel robotic platform, the system required an adaptation period despite preoperative training. The surgical team’s unfamiliarity with new features and the need for more coordinated efforts with assistants to ensure patient safety likely contributed to the prolonged duration, reflecting the expected learning curve associated with any new technology. Second, certain cases involved unexpected intraoperative challenges, such as complex intra-abdominal adhesions and anatomical variations in renal arterial branches, which further extended the operative time.

Additionally, the length of hospital stays for the procedures was longer than usual. This was partly because patients included in the study typically underwent additional preoperative evaluations, including 3D model reconstruction for intraoperative navigation. And some patients, aware that they were undergoing a novel surgical procedure, requested extended hospital stays for safety concern. Finally, the number of patients undergoing RC in this study was limited, which may affect the specificity of the findings. Future clinical studies with larger sample sizes could address these issues.

The small cohort size may contribute to variability in outcomes that could be more accurately assessed in larger-scale studies. Additionally, the findings may be influenced by selection bias, as smaller samples are less likely to represent the entire spectrum of disease variability and patient characteristics. Future research with larger, multicenter cohorts is necessary to validate these preliminary observations and enhance the generalizability of the results across different clinical settings.

The 3-month follow-up period is a limitation that prevents comprehensive assessment of long-term outcomes such as cancer recurrence. Future studies should incorporate longer follow-up to better capture recurrence rates and long-term treatment efficacy.

Conclusions

In conclusion, the Toumai MT-1000 Endoscopic Surgical System has demonstrated its safety and efficacy in urological procedures. It represents a viable option for further clinical research and offers promising prospects due to its advanced features that provide enhanced comfort and accuracy for surgeons.

Acknowledgments

Funding: This study was supported by a grant from National High Level Hospital Clinical Research Funding (Interdisciplinary Research Project of Peking University First Hospital) (No. 2024IR32 to Z.Z.).

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://tau.amegroups.com/article/view/10.21037/tau-24-451/rc

Data Sharing Statement: Available at https://tau.amegroups.com/article/view/10.21037/tau-24-451/dss

Peer Review File: Available at https://tau.amegroups.com/article/view/10.21037/tau-24-451/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-24-451/coif). Z.Z. reports that this study was supported by a grant (No. 2024IR32) from National High Level Hospital Clinical Research Funding (Interdisciplinary Research Project of Peking University First Hospital). The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All patients were informed of the enrolment and risks associated with the Toumai MT-1000 robotic surgeries and provided written consent. The study was approved by the Medical Ethics Committee of Peking University First Hospital Miyun Hospital (No. 2023Yan016-001). The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013).

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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