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The Point of No Return: Robotic-Assisted Colo-Rectal Surgery

Submitted:

21 August 2026

Posted:

24 August 2026

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Abstract
Background. Robotic-assisted colorectal surgery is increasingly adopted; however, evidence regarding outcomes during the early implementation phase remains limited. This study aimed to evaluate the feasibility, safety, and short-term outcomes of a newly established robotic colorectal surgery program at a tertiary referral center. Methods. All consecutive patients undergoing robotic colorectal resection between November 2019 and February 2026 were prospectively recorded and retrospectively analyzed. Perioperative outcomes, conversion rates, postoperative complications, mortality, and histopathological results were assessed. Results. A total of 177 patients were included, with a progressive increase in surgical volume over time. Most procedures were performed for oncological indications (159, 90%), while 18 (10%) were performed for benign diseases. The most frequent procedures were right hemicolectomy (45%), left hemicolectomy (29%), and low anterior rectal resection (23%). Mean operative time was 331.1 ± 75.0 minutes. Conversion to open surgery occurred in 15 patients (8.5%), mainly due to extensive intra-abdominal adhesions, particularly during the early phase of the program. Postoperative complications occurred in 20 patients (11%), while 3 patients (2%) died within 30 days. Major complications (Clavien–Dindo ≥III) occurred in 7%, and anastomotic leakage in 3%. Mean hospital stay was 10.1 ± 7.6 days. R0 resection was achieved in all cases, with adequate lymph node retrieval for staging. Conclusions. Robotic colorectal surgery can be safely implemented at a tertiary center, achieving favorable perioperative and oncological outcomes even during the early learning phase.
Keywords: 
robotic colorectal surgery
;  
learning curve
;  
perioperative outcomes
;  
colorectal cancer
;  
tertiary referral center
Subject: 
Medicine and Pharmacology  -   Surgery

Introduction

Minimally invasive surgery has become increasingly established as the preferred approach for the treatment of benign and malignant colorectal diseases, owing to its well-documented advantages in terms of faster postoperative recovery, shorter hospital stays, and reduced perioperative morbidity, without compromising oncological outcomes [1,2]. These benefits are largely attributable to decreased abdominal wall trauma, limited tissue manipulation, and improved visualization of deep anatomical structures, which are particularly relevant in pelvic surgery. Despite being a well-established technique, conventional laparoscopy has inherent technical limitations, especially in complex cases, including suboptimal instrument ergonomics, dependence on an assistant for camera control, two-dimensional visualization of the operative field, and restricted degrees of freedom. Such factors may translate into technical challenges and higher rates of conversion to open surgery. The introduction of robotic platforms was intended to overcome many of these constraints by providing high-definition three-dimensional vision, stable camera control, and articulated instruments with multiple degrees of freedom, allowing for precise dissection even within confined anatomical spaces such as the pelvis [3]. Consequently, robotic-assisted colorectal surgery has gained increasing adoption worldwide. Available evidence suggests that robotic surgery achieves postoperative and oncological outcomes comparable to those of laparoscopy, with some reports indicating lower conversion rates in high-volume centers [4]. However, most published data originate from institutions with long-established robotic programs, while information regarding outcomes during the early phases of implementation remains limited [5]. Over the past four years, our center has undertaken a structured program of robotic colorectal surgery with the aim of progressively integrating this technology into routine clinical practice. The present study aimed to evaluate our early experience by analyzing perioperative safety, conversion rates, pathological specimen quality, and clinical outcomes, thereby contributing to the growing body of literature on the introduction of robotic colorectal programs in emerging settings.

Patients and Methods

All operations were performed at Policlinico Umberto I (General Surgery and Mini-Invasive Unit, Department of Surgery, Sapienza University of Rome) a tertiary care university hospital. All patients who underwent colorectal robotic surgery at our Institution between November 2019 and February 2026 were included in the present analysis. All operations were performed using a da Vinci X surgical system (Intuitive Surgical, Sunnyvale, CA, USA) with a single-console configuration.
Eligibility criteria comprised age ≥18 years and provision of written informed consent for robotic-assisted surgery, including authorization for conversion to open surgery if required for intraoperative safety considerations. Surgical procedures comprised anterior resection, low anterior resection, right hemicolectomy, and left hemicolectomy.
The indication for surgery was established by a multidisciplinary tumor board comprising colorectal surgeons, gastroenterologists, oncologists, radiologists, and pathologists. All patients underwent elective surgery following a standardized preoperative assessment and optimization pathway. Pre-admission evaluation included comprehensive laboratory testing, electrocardiography, formal cardiology clearance, and anesthesiology assessment. All patients underwent contrast-enhanced total-body computed tomography (CT) for staging purposes; in cases of rectal cancer, pelvic magnetic resonance imaging (MRI) was additionally performed to assess local tumor extension and mesorectal involvement. Endoscopic evaluation with colonoscopy was mandatory in all cases and included biopsy of the primary lesion for histological confirmation. When indicated, endoscopic tattooing was performed to facilitate intraoperative localization of the tumor. Mechanical bowel preparation and perioperative antibiotic prophylaxis were administered according to institutional protocols. All surgical interventions were performed by three different surgeons (GDT, EF, PS) who sequentially operated during the study period. All procedures were performed under general anesthesia with orotracheal intubation, and patients received prophylactic antibiotics (cefazolin 2 g i.v.) at induction. Since 2025, all anastomoses were routinely controlled for perfusion before and after their creation with the use of indocyanine green near-infrared fluorescence. No drains were used for right hemicolectomy, while a single drain was used for low anterior resection and routinely removed on the fourth postoperative day. Nasogastric tube was removed after operation. Enhanced recovery after surgery (ERAS) protocol was adopted since 2025, and, therefore, patients had a limited administration of intravenous fluids in the ICU and prophylactic antithrombotic therapy (heparin sodium 4,000 U.I. s.c.) was suspended at complete patients’ mobilization. Follow-up consisted of clinical assessment and laboratory testing on postoperative day 2 and at 1-month, followed thereafter by outpatient visits every 6-month.

Study Population, Perioperative and Postoperative Variables

Demographic and clinical data were prospectively recorded and included age, sex, surgical indication, preoperative physical status according to the American Society of Anesthesiologists (ASA) classification. Intraoperative parameters encompassed operative duration, number of trocars used, and conversion to laparotomy. Operative time was defined as the interval from skin incision to final wound closure. Postoperative outcomes included length of hospital stay, calculated as the number of postoperative nights spent in hospital, unplanned readmissions within 30 days, postoperative complications, and histopathological results. Recorded complications comprised anastomotic leak, intra-abdominal abscess, surgical site infection, pneumonia, Clostridioides difficile infection, and urinary tract infection. Histopathological assessment included resection margin status and lymph-node harvest, expressed as the total number of retrieved lymph nodes.

Surgical Technique

In all cases, a standardized setup using three of four robotic trocars and two laparoscopic accessory ports was adopted, the latter serving for the camera and bedside assistance. Port placement was tailored according to the side of resection and the specific procedure performed, following a linear abdominal configuration to optimize instrument triangulation, minimize external arm collisions, and ensure adequate exposure of the operative field. Left-sided colonic and rectal resections were carried out using a medial-to-lateral approach, with early identification and division of the inferior mesenteric vessels when indicated and systematic visualization and preservation of the left ureter. The colon was mobilized along the white line of Toldt up to the splenic flexure, which was mobilized robotically at the surgeon’s discretion based on oncological and technical requirements. Rectal resections included both anterior and low anterior resections, with dissection performed above or below the peritoneal reflection and routine total mesorectal excision (TME) according to oncological principles. Right-sided colonic resections were likewise performed using a medial-to-lateral approach, with early identification and division of the ileocolic vessels and central vascular ligation in cases of malignancy. The right colon was fully mobilized along the white line of Toldt to the hepatic flexure. Anastomoses were fashioned using either intracorporeal (since 2025) or extracorporeal techniques. In extracorporeal cases, specimen extraction was performed through a protected extended port site using a wound protector. Left-sided and rectal anastomoses were typically created in an end-to-end fashion with a circular stapling device, whereas right-sided anastomoses were constructed in a side-to-side functional end-to-end configuration using a linear stapler. In patients with prior pelvic radiotherapy or in selected cases of complicated diverticular disease, a diverting loop ileostomy was performed. Throughout the procedure, advanced energy devices (Harmonic®, Ethicon) were employed for dissection, and Hem-o-lok® polymer clips were systematically used for secure vascular control.

Data Extraction

Data was collected using the software program Excel 2024 (ver. 16.89.1) (Microsoft, Redmond, CA, USA) running on an iMac operating with MacOS Monterey (ver. 12.7.6). Data were prospectively collected on an electronic anonymized database containing demographic characteristics, indication for surgery, procedural details, and postoperative complications. Final histopathology information was also obtained. The study was conducted according to the Declaration of Helsinki principles and approved by the Department of Surgery Research Committee. After completing the data extraction, a comparison between patients’ demographics, diagnosis, final histology, surgical technique, and post-operative course was made.

Statistical Analysis

Statistical analysis was performed using SPSS 28.0.1.1 (14) (IBM Corporation, Armonk, NY, USA) running on the same computer. Categorical variables are presented as percentages, and continuous variables are displayed as mean ± standard deviation. Statistical differences were evaluated using the chi-square test for categorical variables.

Results

The cohort included 177 patients who underwent robotic colorectal resections during the study period, with a progressive increase in annual surgical volume observed over time. After a relatively stable phase between 2019 and 2021 (5, 8, and 6 procedures, respectively), a significant rise was observed starting from 2022 (n=27), followed by a steady increase in 2023 (n=35), 2024 (n=43), and 2025 (n=46). Data for 2026 are partial (n=7) and were not considered for trend evaluation.
Male patients accounted for 114 (64%), while 63 (36%) were female. The mean age was 69.0 ± 11.9 years (range 38-90 years). A total of 73 (41%) patients were classified as American Society of Anesthesiologists (ASA) grade II, while 104 (59%) were classified as ASA grade III.
Most procedures were performed for oncologic indications 159 (90%) patients while 18 (10%) patients underwent surgery for benign disease, mainly due to recurrent diverticulitis or diverticular stenosis.
The distribution of procedures showed a predominance of right hemicolectomy representing the most frequently performed operation 80 (45%), followed by left hemicolectomy 56 (32%), and anterior and low anterior rectal resection 41 (23%). Additional procedures were performed in selected cases and included 11 (6%) protective ileostomies, 2 (1%) partial cystectomies for a sigmoid–vesical fistula, 5 (3%) cholecystectomies performed during right hemicolectomy, 1 (1%) cholecystectomy during left hemicolectomy, and 4 (2%) oophorectomies.
The mean operative time was 331.1 ± 75.0 minutes (range 170–540). Conversion to open surgery occurred in 15 (8.5%) patients. The primary indication for conversion was extensive intra-abdominal adhesions 8 cases. Additional reasons included severe obesity 2 cases, lower rectal infiltration 2 cases, splenic injury bleeding 1 case, severe abdominal distension 1 case and intolerance to pneumoperitoneum 1 case. All conversion occurred in the first years of our experience.
Twenty-two (15%) intraoperative anastomoses were performed, primarily in patients operated on from 2025 onwards, reflecting a shift in surgical practice in the later study period.
Postoperative complications occurred in 20 (11%), with a 30-day mortality rate of 2% (3 patients).
According to the Clavien–Dindo classification, 8 (4%) patients experienced minor complications (grade I–II), while 12 (7%) patients developed major complications (grade ≥III). Among these, 11 (6%) patients had complications of grade ≥ IIIB.
Surgical site infection and postoperative ileus were each observed in 1 patient (1%). Minor complications included one case of infective endocarditis managed with targeted antibiotic therapy, one case of postoperative fever of unknown origin, and one pleural effusion treated conservatively.
Anastomotic leakage occurred in 6 (3%) patients. Management strategies varied according to clinical presentation: one patient was treated conservatively with antibiotics (in the presence of a diverting ileostomy), one underwent percutaneous drainage combined with endoscopic stent placement (also with a protective ileostomy), and four required surgical re-intervention.
A Clavien–Dindo grade IVA complication was observed in one patient, who developed a postoperative non-ST-elevation myocardial infarction requiring coronary angiography followed by cardiac surgery.
Regarding mortality, one patient experienced intraoperative cardiac arrest. Two additional deaths were due to septic shock: one secondary to KPC-related pneumonia and one due to polymicrobial infection (KPC and Escherichia coli).
The mean hospital-stay after surgery 10.1 ± 7.6 days (range 3–51).
Regarding histopathological outcomes, 18 (11%) patients underwent surgery for diverticular disease; in these cases, a complete oncological staging was not performed, and therefore TNM classification, resection margin status (R), and lymph node assessment for oncological purposes were not applicable. In the remaining patients who underwent resection for neoplastic disease, an R0 resection was achieved in 100% of cases. The number of retrieved lymph nodes was available in all patients. Quantitative analysis showed a mean of 17.2±8.1 lymph nodes examined per patient, with a median of 16 lymph nodes. Lymph node metastases were identified in 41 (23%) patients. Histopathological evaluation allowed pathological staging according to the TNM classification in oncological patients, with a distribution including early-stage disease (stage 0–I) in 39 patients, locally advanced disease (stage II–III) in 88 patients, and a minor proportion of metastatic disease (stage IV) in 4 patients, among those with available staging data.

Discussion

The present study reports the early experience of a robotic colorectal surgery program implemented in a tertiary referral center. Our findings demonstrate that the introduction of robotic technology into routine colorectal practice is both feasible and safe, with acceptable perioperative morbidity, low conversion rates, and satisfactory pathological outcomes, even during the initial phase of adoption. Importantly, these results were achieved in a real-world setting, outside of high-volume centers with long-standing robotic expertise, thereby reflecting the practical challenges of program implementation.
Minimally invasive colorectal surgery has evolved significantly over recent decades, with laparoscopy representing the standard approach in many institutions [6]. However, well-recognized technical limitations—particularly in confined anatomical spaces such as the pelvis—have driven the increasing adoption of robotic platforms. In this context, the enhanced three-dimensional visualization and improved instrument dexterity offered by robotic systems may translate into more precise dissection and improved surgeon ergonomics, potentially facilitating complex procedures.
The conversion rate represents a key quality indicator, particularly during the implementation phase of a robotic program. In our cohort, conversion to open surgery occurred in 8.5% of cases, which compares favorably with previously reported data from both laparoscopic and robotic series which ranges between 8%and 10% [7,9]. Notably, this rate was maintained despite the inclusion of unselected patients and the progressive expansion of surgical indications. The main cause of conversion was extensive intra-abdominal adhesions, confirming that patient-related factors, rather than limitations of the robotic platform itself, remain the primary determinants of conversion. These findings suggest that robotic surgery may help mitigate some technical challenges, even during the learning curve, when supported by a structured and multidisciplinary environment.
Postoperative morbidity in our study was consistent with the available literature [10]. Overall complication rates remained within acceptable limits, and the incidence of major complications (Clavien–Dindo ≥IIIb) was comparable to that reported in similar minimally invasive series. The anastomotic leak rate of 3% further supports the technical reliability of robotic colorectal surgery. Importantly, mortality was low and primarily related to severe systemic complications rather than intraoperative technical failure, highlighting the complexity and comorbidity burden of patients typically managed in a tertiary referral setting. A relevant finding is the progressive adoption of intracorporeal anastomosis. This shift likely reflects increasing confidence and technical proficiency with the robotic platform [11]. The use of intracorporeal reconstruction may offer advantages such as reduced bowel manipulation and improved precision, facilitated by enhanced visualization and instrument dexterity [12]. In our series, its implementation did not adversely affect perioperative outcomes, suggesting that it represents a safe and reliable technique even during the learning phase. In addition, temporal trends in operative time and conversion rates suggest progressive improvement in surgical performance, supporting the concept that proficiency can be achieved with structured experience.
From an oncological perspective, the achievement of R0 resection in all cases and the adequacy of lymph node retrieval confirm that robotic surgery does not compromise oncological principles, even during the early phase of adoption [13]. Furthermore, the heterogeneous distribution of tumor stages indicates that the robotic approach was progressively applied across a broad spectrum of disease, rather than being restricted to highly selected early-stage tumors. This aspect strengthens the external validity of our findings and reflects real-world clinical practice.
This study has several limitations. First, it represents a single-center experience, which may limit generalizability. Second, the absence of a direct laparoscopic group as a control group prevents definitive conclusions regarding superiority [14]. Third, although data were prospectively collected, the analysis remains retrospective in nature. Finally, long-term oncological outcomes are not yet available and will require further follow-up.
An additional consideration, emerging from our experience, relates to the concept of a “point of no return” in the adoption of robotic colorectal surgery. As surgical proficiency increases and familiarity with the robotic platform improves, the perceived advantages in terms of visualization, precision, and ergonomics become progressively more evident. In this context, reverting to conventional laparoscopy after completing the learning curve may become increasingly challenging, not only from a technical standpoint but also in terms of surgical workflow and operator comfort. This phenomenon reflects a paradigm shift rather than a simple technological transition, suggesting that robotic surgery, once fully integrated into clinical practice, may redefine the standard approach for complex colorectal procedures. Our findings, particularly the progressive adoption of advanced techniques such as intracorporeal anastomosis and the stability of outcomes despite increasing case complexity, further support this interpretation.

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