Müller-Stich, Beat Peter

Objective: To evaluate the institutional learning curve of robotic liver resection (RLR), its association with surgical complexity and outcomes in an international multicenter cohort. Summary of Background Data: RLR is increasingly adopted worldwide, but the dynamics of the learning process and its impact on surgical outcomes remain poorly defined. Methods: This international, multicenter, retrospective cohort study included consecutive patients who underwent RLR between 06/2013 and 12/2024 across 22 expert centers. Based on the first 150 cases at each center, three phases were used to define the learning curve: operative time for competency, major complications for proficiency, and textbook outcome for mastery. Risk-adjusted generalized additive models were used to assess the learning process. Benchmark performance was compared to international reference values. Results: Among 2,331 patients, the most common indications were hepatocellular carcinoma (36%), benign lesions (23%) and colorectal liver metastases (21%). Operative time decreased after achieving competency (case #62), from 240 to 220 minutes ( P <0.001). Major morbidity reached a plateau during the proficiency phase (cases #63–138; 9% vs. 11%, P =0.144), while progression to mastery (cases #139–150) was associated with a higher rate of textbook outcome (76% vs. 87%, P =0.021). In contrast, conversion (5.1% vs. 4.9% vs. 2%), bile leak (4.0% vs. 5.3% vs. 3.8%), and 90-day mortality (0.7% vs. 0.9% vs. 0.9%) remained low and stable across all learning phases. Importantly, benchmark criteria for operative time, hospital stay, and textbook outcome were met across all complexity groups, including during the early learning phase. Conclusions: Robotic liver surgery shows progressive outcome improvement with early achievement of benchmark-level results and stable performance across increasing complexity. These findings indicate that, in experienced centers, RLR can be safely implemented and integrated into clinical practice, supporting its key role in modern hepatobiliary surgery.

Importance Total pancreatectomy (TP) is indicated for advanced pancreatic cancer or multifocal tumors. Furthermore, TP may be performed to avoid the risk of pancreatic fistula in selected patients to improve the perioperative risk profile. Objective To define reference values for TP based on a low-risk cohort treated at expert centers. Design, Setting, and Participants This multicenter study analyzed outcomes from patients undergoing primary TP for malignant or benign lesions from 25 international expert centers from January 2017 to November 2023. Low-risk patients undergoing TP (LR-TP) were without vascular resections or significant comorbidities. Exposures TP. Main Outcomes and Measures Twenty reference values were derived from the 75th or the 25th percentile of the median values of all centers. Outcomes of LR-TP were compared with a cohort of TP with vascular resection, TP due to high-risk pancreatic anastomosis, and the benchmark values for low-risk pancreatoduodenectomy. Results Of 994 patients, 333 (33.5%; median [IQR] age, 66 [58-72] years; 171 male [51.4%]) qualified as the LR-TP cohort. Reference values included blood loss (≤1000 mL), major complications (≤37%), 3-month postoperative mortality (&amp;lt;6%), and retrieved lymph nodes (≥29). Compared with TP with vascular resections, reference cutoffs were not met for major complications (51% vs LR-TP ≤37%) and 90-day mortality (11% vs LR-TP ≤6%). For TP due to high-risk anastomosis, failure to rescue rate (38% vs ≤6%) and 90-day mortality (11% vs LR-TP ≤6%) were not met. Compared with pancreatoduodenectomy, reference values for postoperative mortality were 3 times higher for LR-TP (≤2% vs ≤6%) and less for resected lymph nodes (≥16 vs ≥29). Conclusions and Relevance This case-control study provided global reference values for TP, indicating significantly higher postoperative morbidity and mortality compared with pancreatoduodenectomy. Perioperative morbidity of TP was especially increased in patients with vascular resections. These reference values can serve for quality control of pancreatic surgery.

Objective: To establish benchmark cutoffs for robotic liver resection (R-LR), encompassing both major and minor resections, and to determine the impact of patient selection on outcomes. Background: R-LR is a key advancement in minimally invasive liver surgery but lacks standardized benchmarks, especially for minor resections. While guidelines endorse R-LR, its role in optimizing outcomes remains unclear. This study establishes the first benchmarks for R-LR, enabling comparisons across surgical modalities and refining patient selection. Methods: This retrospective, multicenter study analyzed consecutive adult patients undergoing R-LR at 30 international centers (2020–2023). Benchmark centers had an annual case volume of ≥15 R-LR. Benchmark criteria included ASA ≤2, no major comorbidities, no prior liver resections, and Child-Pugh A status. Benchmark cutoffs for 14 key outcomes were set at the 50th and 75th percentiles of median values across benchmark centers. Multivariable logistic regression identified predictors of textbook outcomes. Results: Eighteen high-volume centers contributed 4028 cases with 2632 (65.3%) meeting benchmark criteria. Malignancy was the indication in 29.6%, most commonly hepatocellular carcinoma followed by colorectal liver metastases. Major liver resection was performed in 42.6%. The distribution of Iwate difficulty scores was low (25.4%), intermediate (53.9%), advanced (15.9%), and expert (4.9%). Benchmark cutoffs were established for minor and major resection, and stratified by Iwate low (0-3), intermediate (4-6) and high (7-12): Open conversion (≤6.5% minor, ≤10.5% major), major complications within 90 days (≤5.2% minor, ≤16.7% major), R1 resection (≤9.2% minor, ≤6.7% major). Benchmark cases performed at low-volume centers were able to achieve outcomes within the corresponding benchmark cutoffs. In fact, patient selection reflected by the proportion of benchmark patients, rather than case volume, was associated with textbook outcomes. Conclusions: This study defines R-LR benchmarks, emphasizing patient selection over center volume for optimal outcomes. Benchmark cutoffs guide training and support the expansion of R-LR.

Summary of Background Data: Intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic cancer is typically managed like pancreatic intraepithelial neoplasia (PanIN)-derived pancreatic cancer. However, in IPMN-derived pancreatic cancer, the role of chemotherapy remains controversial, particularly in the neoadjuvant setting (NAT). Objective: To evaluate the role of neoadjuvant chemotherapy in IPMN-derived pancreatic cancer. Methods: Patients with IPMN-derived pancreatic cancer treated with either upfront surgery (US) or NAT were identified from eight international centers (2000-2023). Clinicopathologic data were compared. Date of first treatment was used for Kaplan-Meier and log-rank tests to compare overall (OS) and recurrence free survival (RFS). Multivariable Cox-regression was performed in patients that underwent NAT. Results: In 1,019 patients, 76 (7%) underwent NAT. Patients who received NAT had higher baseline CA19-9 levels (P<0.001). Of these 76 patients, 27 (36%), 20 (26%), and 29 (38%) had resectable, borderline resectable, or locally advanced pancreatic cancer at diagnosis, respectively. Advanced resectability stage was significantly more common in the NAT patients as compared to those who underwent US (P<0.001). OS for US patients was 38.0 months (95%CI: 33.7.1-44.3), which was not statistically different than those that received NAT [27.5 mo (95%CI: 23.1-46.7), P=0.121]. This was also valid for patients with resectable disease [US: 38.1 mo vs. NAT: 35.6 mo, P=0.920)]. Complete or marked pathological treatment response (P=0.046) and serological CA19-9 normalization after NAT (P=0.017) were associated with improved survival. On Cox-regression for OS, N2 disease [HR: 4.15 (95%CI: 1.71-10.10)], elevated CA19-9 [HR: 2.02 (95%CI:1.06-3.85)] and R1 margin [HR: 2.36 (95%CI:1.20-4.61)] was independently associated with OS after NAT, while resectability status was not. Conclusion: After NAT and resection, advanced resectability stage was not associated with worse OS indicating the value of this approach for borderline resectable and locally advanced IPMN-derived pancreatic cancer. The benefit of NAT in resectable disease is unclear and may require an individualized approach. Biological treatment effect can be assessed with CA19-9 and confirmed by pathologic response.