Conversion from Minimally Invasive to Open Pancreatectomy Carries Higher Complication Risk, Study Finds

Background

Left-sided pancreatectomy, also known as distal pancreatectomy, is a surgical procedure performed to remove the left portion of the pancreas. This intervention is commonly indicated for benign tumors, such as pancreatic neuroendocrine tumors, cystic lesions, and malignant neoplasms including pancreatic ductal adenocarcinoma. Over the past two decades, minimally invasive surgery (MIS) has been increasingly adopted for pancreatic resections, offering potential benefits such as reduced postoperative pain, shorter hospital stays, and improved cosmetic outcomes.

However, the transition from minimally invasive to open surgery during these procedures, known as conversion, represents a significant clinical scenario that warrants careful investigation. Surgeons may convert to an open approach due to various factors including uncontrolled bleeding, difficulty in visualizing anatomical structures, tumor invasion into adjacent tissues, or anatomical variations that complicate the minimally invasive approach. Understanding the outcomes associated with conversion is crucial for surgical planning, patient counseling, and quality improvement initiatives.

Despite the widespread adoption of minimally invasive techniques for left-sided pancreatectomy, data comparing outcomes across pure minimally invasive, pure open, and converted procedures remain limited. This knowledge gap has implications for both clinical decision-making and patient expectations.

Study Design

Researchers conducted a retrospective analysis using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. The study included adult patients who underwent elective left-sided pancreatectomy between 2019 and 2023. Patients were classified into three distinct groups based on their surgical approach: those who underwent complete minimally invasive left-sided pancreatectomy (MIS group), those who underwent open left-sided pancreatectomy (Open group), and those who began as minimally invasive procedures but required conversion to open surgery (Conversion group).

The research team collected and analyzed patient demographics, intraoperative variables, and 30-day postoperative outcomes. Both univariate and multivariate statistical analyses were performed to compare outcomes across the three groups. The primary endpoints included overall complications, major complications, operative time, and mortality. Multivariate regression analysis was employed to identify factors independently associated with adverse postoperative outcomes.

Key Findings

The analysis included a total of 11,262 patients who underwent elective left-sided pancreatectomy during the study period. The distribution of surgical approaches revealed that 5,458 patients (48.5%) underwent minimally invasive left-sided pancreatectomy, 5,145 patients (45.7%) underwent open left-sided pancreatectomy, and 659 patients (5.9%) required conversion from minimally invasive to open surgery.

A notable finding regarding patient characteristics showed that individuals who required conversion were significantly older and presented with more comorbidities compared to those in the other two groups. This observation suggests that patient-related factors may influence the likelihood of conversion and potentially contribute to postoperative outcomes.

Operative time differed significantly across the three groups. The conversion group had the longest operative time at 275 minutes on average, compared to 219 minutes for the minimally invasive group and 212 minutes for the open surgery group (P < .001). This 56-minute difference between the conversion and pure MIS groups highlights the additional surgical complexity and time required when conversion becomes necessary.

Postoperative outcomes demonstrated substantial differences across the groups. Patients in the conversion group experienced significantly higher rates of overall complications, major complications, and mortality compared to both the MIS and open surgery groups (P < .001). These findings indicate that conversion to open surgery is associated with inferior short-term outcomes.

Multivariate regression analysis revealed that conversion was independently associated with increased odds of major complications (odds ratio 1.381, 95% confidence interval 1.149-1.660; P = .001) and overall complications (odds ratio 1.291, 95% confidence interval 1.083-1.538; P = .004). These associations persisted after adjusting for potential confounders including patient demographics, comorbidities, and procedural factors.

Expert Commentary

The findings from this large retrospective study provide valuable insights into the clinical implications of surgical conversion during minimally invasive left-sided pancreatectomy. The independent association between conversion and increased complications suggests that conversion itself may represent a marker of surgical complexity rather than a causative factor for poor outcomes.

Several important considerations emerge from these data. First, the higher complication rates observed in the conversion group likely reflect underlying patient- and disease-related factors that necessitated the conversion in the first place. Patients with more advanced disease, difficult anatomical presentations, or greater comorbidity burden may be both more likely to require conversion and more prone to postoperative complications. This confounding by indication is a limitation inherent to retrospective analyses.

Second, the significantly longer operative time in the conversion group highlights the surgical burden associated with these procedures. When conversion occurs, surgeons must essentially complete two procedures: the initial minimally invasive portion and the subsequent open reconstruction. This extended operative time may contribute to increased blood loss, longer anesthesia exposure, and greater physiological stress, all of which could influence postoperative outcomes.

From a clinical perspective, these findings emphasize the importance of thorough preoperative evaluation and risk stratification. Surgeons should carefully assess patient-specific factors, tumor characteristics, and anatomical considerations when deciding on a surgical approach. While minimally invasive surgery offers numerous benefits, the selection of appropriate candidates is essential to minimize unplanned conversions and optimize outcomes.

The study’s strengths include its large sample size, use of a validated national database, and rigorous statistical methodology. However, limitations include the retrospective design, which precludes causal inferences, and the lack of detailed information regarding the specific indications for conversion. Additionally, the ACS-NSQIP database captures only 30-day outcomes, limiting the assessment of long-term results such as recurrence-free survival or quality of life measures.

Conclusion

This comprehensive analysis of over 11,000 patients demonstrates that conversion from minimally invasive to open left-sided pancreatectomy is independently associated with significantly higher risks of postoperative complications. The findings highlight the need for improved preoperative risk stratification and careful patient selection to minimize unplanned conversions and optimize surgical outcomes.

Healthcare providers should incorporate these data into their clinical decision-making processes and patient counseling discussions. While minimally invasive approaches offer clear benefits when appropriate, recognizing the factors associated with conversion risk can help surgical teams better prepare for potential challenges and potentially modify their operative strategies when indicated.

Future research directions should include prospective studies examining the long-term outcomes of converted procedures, investigation of specific conversion triggers, and development of validated prediction models to identify patients at high risk for conversion. Such efforts will further enhance the safety and effectiveness of surgical care for patients undergoing left-sided pancreatectomy.

References

Ebadinejad A, Almeflehi M, Angle E, Kotla A, Davis AP, Aziz H. Impact of conversion to open surgery on outcomes following minimally invasive left-sided pancreatectomy. Surgery. 2026-03-28:110163. PMID: 41905829.