2025 Volume 11 Issue 1 Article ID: cr.25-0035
INTRODUCTION: Experience with the Hugo RAS system in robot-assisted colorectal surgery is limited. This is particularly noticeable when focusing on complex procedures, such as total proctocolectomy (TPC). This study aimed to demonstrate the feasibility and safety of using the Hugo RAS system for TPC.
CASE PRESENTATION: A 27-year-old woman with multiple colorectal cancers with a background of familial adenomatous polyposis underwent robot-assisted TPC, including lymph node dissection of the entire colorectal region using the Hugo RAS system. The robotic procedure was divided into 3 steps: 1) Trendelenburg position to perform ascending colon complete mesocolic excision (CME) to the hepatic flexure, 2) descending colon CME and total mesorectal excision with D3 lymph node dissection, and 3) flat position to perform central vessel ligation along the superior mesenteric artery. After undocking, the specimen was extracted transanally, and an ileal pouch was constructed from a small laparotomy at the umbilical incision, followed by ileal pouch-anal anastomosis. The operative time was 632 min, and the estimated blood loss was minimal. The postoperative period was uneventful.
CONCLUSIONS: Robot-assisted TPC using the Hugo RAS system is safe and feasible. The flexibility of Hugo, which is carried by a modular-type surgical robot with multiple independent arms, enables safe and effective advanced procedures.
complete mesocolic excision
CTcomputed tomography
CVLcentral vessel ligation
FAPfamilial adenomatous polyposis
IMAinferior mesenteric artery
IMVinferior mesenteric vein
IPAAileal pouch-anus anastomosis
MCAmiddle colic artery
PODpostoperative day
SMAsuperior mesenteric artery
SMVsuperior mesenteric vein
TMEtotal mesorectal excision
TPCtotal proctocolectomy
Robotic-assisted surgery has become the preferred approach for colorectal procedures because of its minimally invasive nature. It provides advantages, such as reduced postoperative pain, shorter hospital stays, and faster recovery than traditional open surgery.1–3) The Hugo RAS system is an innovative surgical robot designed to enhance operational flexibility, as it is a modular-type surgical robot with multiple independent arms mounted onto independent surgical carts. In addition, it also offers a wide range of joint motion, which enables us to perform upper to lower abdominal surgery from the same trocars (Supplementary Fig. S1).
To date, experience with the Hugo RAS system in colorectal surgeries has been limited, with most reports focusing on major surgeries, such as right or left hemicolectomies and rectal anterior resection.4) The application of Hugo for total proctocolectomy (TPC), especially with comprehensive lymphadenectomy across multiple regions of the colorectum, presents unique technical challenges that require precise coordination of the robotic arms for optimal access and control across different abdominal quadrants from the upper side to the lower pelvic floor.
Here, we present the first case of robot-assisted TPC with D3 lymphadenectomy across the entire colorectum using the Hugo RAS system in a patient with familial adenomatous polyposis (FAP) complicated by multiple colorectal cancers. This case demonstrates the safety and feasibility of multi-quadrant colorectal surgery using Hugo.
A 27-year-old woman with multiple colorectal cancers on a background of FAP was presented to our department. Notably, a large lesion was detected in the ascending, transverse, and sigmoid colon and the upper rectum, and pathological examination confirmed some of them as adenocarcinoma. Preoperative computed tomography revealed multiple lymph node swellings along the inferior mesenteric artery (IMA) and middle colic artery, without any evidence of distant metastases. After a comprehensive evaluation by a multidisciplinary cancer board, we decided to perform TPC with lymph node dissection of the entire colorectal region, using the Hugo RAS system as a surgical device.
Robot-assisted TPC using the Hugo RAS system was approved by the Evaluating Committee for Highly Difficult New Medical Technologies (approval number H-0051) and the Institutional Review Board at Kyoto University.
Under general anesthesia, the patient was placed in a lithotomy position with the arms tucked. After a 5-cm vertical skin incision was made at the umbilicus, a wound-protecting device was applied. After pneumoperitoneum, 4 robotic trocars and 2 assistant trocars were placed (Fig. 1A). The instruments used in robot-assisted TPC with Hugo were a camera, monopolar curved shears for the right hand, bipolar fenestrated forceps for the left hand, and Cadiere/double fenestrated forceps for the reserve arm (Table 1). Robot-assisted TPC with Hugo consists of 3 distinct steps (Fig. 1B), followed by transanal specimen extraction, ileal pouch construction through a small laparotomy, and ileal pouch-anus anastomosis (IPAA). Two table positions, Trendelenburg and flat, were required, each with specific docking tilts but the same angles of the arm carts throughout the robotic procedure. The detailed operative procedure is presented in Supplementary Videos. Details of the docking angles, tilts, and instruments of the robotic arm at each step are presented in Figs. 1A and 1C, and Table 1.
TPC, total proctocolectomy
Table position | Arm | Role | Instrument | Docking angle | Tilt | |
---|---|---|---|---|---|---|
Step 1 | Trendelenburg | 1 | Reserve | Cadiere forceps | 90 | 15 |
2 | Right hand | Monopolar curved shears | 135 | −5 | ||
3 | Camera | 30° oblique | 180 | −20 | ||
4 | Left hand | Bipolar fenestrated forceps | 320 | 30 | ||
Step 2 | Trendelenburg | 1 | Reserve | Cadiere forceps | 90 | 15 |
2 | Left hand | Bipolar fenestrated forceps | 135 | −5 | ||
3 | Camera | 30° oblique | 180 | −20 | ||
4 | Right hand | Monopolar curved shears | 320 | 30 | ||
Step 3 | Flat | 1 | Right hand | Monopolar curved shears | 110 | 15 |
2 | Camera | 30° oblique | 140 | 0 | ||
3 | Left hand | Bipolar fenestrated forceps | 195 | 15 | ||
4 | Reserve | Cadiere forceps | 320 | −30 |
TPC, total proctocolectomy
Step 1: Ascending colon complete mesocolic excision (CME)
The ascending colon CME from the caudal approach proceeded until the completion of the hepatic flexure mobilization (Supplementary Video S1).
Step 2: Central vessel ligation (CVL) of the IMA, descending colon CME, and total mesorectal excision (TME)
After CVL of the IMA, descending colon CME proceeded until the completion of splenic flexure mobilization, followed by TME until the intersphincteric space was fully exposed (Supplementary Video S2).
Step 3: CVL along the superior mesenteric artery (SMA)
After undocking all the robotic arms, the patient was placed in a flat position. Then, CVL along the SMA was performed to ligate the ileocolic, right colic, and middle colic vessels (Supplementary Video S3). The final step of this procedure was the ligation of the inferior mesenteric vein (IMV) at its root, which was exposed in Step 2.
Transanal and small laparotomy proceduresAfter transection of the terminal ileum, we extracted the specimen transanally by excising the rectal mucosa entirely from just below the dentate line because of multiple adenomas in the anal canal. After constructing the ileal pouch through the small umbilical incision and confirming that the ileal pouch could reach the bottom of the anal canal for anastomosis, transanal hand-sewn IPAA was performed. A diverting ileostomy was not performed.
All 3 steps were completed without conversion to open surgery. After undocking Hugo when we finished Step 3, we performed a laparoscopy to confirm hemostasis, specimen extraction, and appropriate anastomosis. The operative time was 632 min (36 min for Step 1, 160 min for Step 2, 188 min for Step 3, and 248 min for other procedures such as positioning, docking, specimen extraction, and anastomosis), with a minimal intraoperative estimated blood loss of 20 mL. The patient exhibited an uneventful postoperative recovery, with gas passage and initiation of liquid nutrition on postoperative day 1 (POD 1) and a solid diet on POD 3 with a functional ileal pouch and satisfactory anal function. A photograph of the abdomen taken 3 months postoperatively is shown in Fig. 2A. Pathological examination revealed 2 sigmoid colon cancers (S1, Type 0-Ip, 55 × 50 mm, tub1, T1b, ly0, v0; S2, Type 0-Isp, 55 × 50 mm, tub1, Tis, ly0, v0) and 1 rectal cancer (R1, Type 0-Ip, 40 × 35 mm, tub1, Tis, ly0, v0). It also revealed 18 out of 89 positive lymph nodes, all of which belonged to the sigmoid colon and rectosigmoid lesions (stations #241, 242, and 251), resulting in UICC pT1bN2b stage (Fig. 2B).
Robot-assisted surgery has become a standard approach in several surgical fields worldwide.5–8) We performed robot-assisted TPC using the Hugo RAS system for the first time. Total console time was 384 min, which was acceptable because this case required D3 lymphadenectomy across the entire colorectum. However, the non-console time was 248 min, which can be improved by repeating this procedure as a team.
The Hugo RAS system is one of the newly launched robotic systems. It features a modular-type robotic system with 4 independent arms mounted onto independent surgical carts. They allow configuration freedom by considering both the surgeon’s preference and patient characteristics. Therefore, proper arm positioning and docking angles are critical to ensure procedural feasibility and efficiency because they help prevent arm collisions and facilitate access to multiple abdominal quadrants.9) Moreover, the range of the arm joint is expansive, reaching 180° when combined with tilt, which allows surgeons to complete surgeries with extended surgical fields, such as TPC (Supplementary Fig. S1). This case requires operations in the deep pelvis and lymph node dissection along SMA/superior mesenteric vein (SMV). Also, it is often difficult to proceed with robot-assisted TPC in the splenic flexure, the boundary between the surgical areas centered on the right colon and the rectum due to limitations in arm movement. In such cases, proper patient positioning with a wide range of joint motion of the Hugo arms helps precise procedures. The open surgeon console also improves team communication and enables observers (e.g., trainees) to follow the operation using 3-dimensional visualization. Pistol-like grips, which resemble those of laparoscopic instruments, also offer high compatibility to laparoscopic surgeons without prior surgical robot experience.10,11)
A limitation of the Hugo RAS system in major colorectal surgeries is the absence of wristed robotic advanced energy devices, clip appliers, and wristed linear staplers.11–13) In this case, the console surgeon only used monopolar curved shears for lymphadenectomy, and the patient-side assistant clipped the vessels for CVL. Some TPC cases, such as FAP with only adenomas or ulcerative colitis, do not need lymphadenectomy across the entire colon. In such cases, advanced energy devices are essential to dissect along the colorectum for efficient and speedy dissection.
To the best of our knowledge, this is the first reported case of robot-assisted TPC, including lymph node dissection of the entire colorectal region, performed using Hugo. Previous reports of robot-assisted TPC using da Vinci Xi showed similar port placement.14–16) Da Vinci Xi requires boom rotation when switching between upper and lower abdominal procedures, whereas Hugo requires tilt adjustment when changing patient position, which is the difference between boom- and modular-type surgical robots. In Japan, colorectal cancer surgery using the Hugo RAS system has gradually become widespread. Even for standard procedures such as right hemicolectomy or rectal anterior resection, optimal trocar placement remains a topic of debate.4,17) Moreover, performing TPC with lymph node dissection across the entire colorectal region adds further complexity. We considered TPC to be a combination of standard right hemicolectomy and rectal anterior resection. During Step 3, minor arm interference was encountered while mobilizing the transverse colon and approaching the middle colic vessels. However, the procedure was completed without any complications, and CME, CVL, and TME were achieved with Hugo.
Robot-assisted surgery for colorectal cancer is a promising procedure that produces better short- and long-term outcomes than conventional laparoscopy.1–3,5) However, it is reported that robotic surgery requires higher costs than conventional laparoscopy.18) Therefore, to facilitate the widespread use of robotic surgery, it is important to lower these costs. The unit prices of Hugo devices are lower than those of other robotic systems (Supplementary Table S1), which may contribute to their widespread use. The patient had good perioperative recovery without any postoperative complications. The patient’s short-term quality of life and psychological status were high, with no diverting stoma or urinary incontinence. Therefore, we can say that robot-assisted TPC using Hugo is of high quality.
We report the first case of robot-assisted TPC, including lymph node dissection of the entire colorectal region, for FAP with multiple colorectal cancers using the Hugo RAS system, achieving safe and oncologically appropriate surgery. The Hugo RAS system represents an emerging minimally invasive robotic platform capable of facilitating procedures, such as TPC as well as standard colorectal surgeries.
Joint movement of the robotic arm. The upper panel shows the maximum extension of the arm with a negative tilt, which enables it to reach a flat position to the right. The lower panel shows the minimum contraction of the arm with a positive tilt, which enables it to reach a flat position to the left.
Supplementary Table S1Original unit prices (JPY).
Supplementary VideosRobot-assisted total proctocolectomy using the Hugo RAS system.
Supplementary Video S1Step 1: Retroperitoneal approach for ascending colon CME until hepatic flexure mobilization.
Supplementary Video S2Step 2: Descending colon CME and TME. Following IMA ligation, dissection proceeds toward the IMV through the omental bursa. TME is then performed, advancing from the retrorectal space to the intersphincteric plane.
Supplementary Video S3Step 3: After repositioning the patient, CVL along the SMA and SMV was performed, including sequential ligation of the ileocolic, right colic, and middle colic vessels, and IMV.
No funding was received for this study.
Authors’ contributionsYY conceived and designed the study and drafted the manuscript.
YA, YI, KH, RO, MM, NH, HM, AI, KK, HK, SH, ST, and KO critically revised the article and approved the final version for publication.
All authors have read and approved the manuscript.
Availability of data and materialsAll data supporting the conclusions of this study are included in the published article.
Ethics approval and consent to participatePatient privacy was considered, and the manuscript includes no identifying information. Our institution does not require ethical approval for case reports.
Consent for publicationThe patient provided informed consent for the publication of this case.
Competing interestsThe authors declare the following potential conflict of interest: Kazutaka Obama and Koya Hida have received honoraria from Medtronic. The other authors declare that they have no competing interests.