Laparoscopic Distal Pancreatectomy: Learning Curve and Experience in a Tertiary Center

Learning Curves of Minimally Invasive Distal Pancreatectomy in Experienced Pancreatic Centers

Importance

Understanding the learning curve of a new complex surgical technique helps to reduce potential patient harm. Current series on the learning curve of minimally invasive distal pancreatectomy (MIDP) are mostly small, single-center series, thus providing limited data.

Objective

To evaluate the length of pooled learning curves of MIDP in experienced centers.

Design, Setting, and Participants

This international, multicenter, retrospective cohort study included MIDP procedures performed from January 1, 2006, through June 30, 2019, in 26 European centers from 8 countries that each performed more than 15 distal pancreatectomies annually, with an overall experience exceeding 50 MIDP procedures. Consecutive patients who underwent elective laparoscopic or robotic distal pancreatectomy for all indications were included. Data were analyzed between September 1, 2021, and May 1, 2022.

Exposures

The learning curve for MIDP was estimated by pooling data from all centers.

Main Outcomes and Measures

The learning curve was assessed for the primary textbook outcome (TBO), which is a composite measure that reflects optimal outcome, and for surgical mastery. Generalized additive models and a 2-piece linear model with a break point were used to estimate the learning curve length of MIDP. Case mix-expected probabilities were plotted and compared with observed outcomes to assess the association of changing case mix with outcomes. The learning curve also was assessed for the secondary outcomes of operation time, intraoperative blood loss, conversion to open rate, and postoperative pancreatic fistula grade B/C.

Results

From a total of 2610 MIDP procedures, the learning curve analysis was conducted on 2041 procedures (mean [SD] patient age, 58 [15.3] years; among 2040 with reported sex, 1249 were female [61.2%] and 791 male [38.8%]). The 2-piece model showed an increase and eventually a break point for TBO at 85 procedures (95% CI, 13-157 procedures), with a plateau TBO rate at 70%. The learning-associated loss of TBO rate was estimated at 3.3%. For conversion, a break point was estimated at 40 procedures (95% CI, 11-68 procedures); for operation time, at 56 procedures (95% CI, 35-77 procedures); and for intraoperative blood loss, at 71 procedures (95% CI, 28-114 procedures). For postoperative pancreatic fistula, no break point could be estimated.

Conclusion and Relevance

In experienced international centers, the learning curve length of MIDP for TBO was considerable with 85 procedures. These findings suggest that although learning curves for conversion, operation time, and intraoperative blood loss are completed earlier, extensive experience may be needed to master the learning curve of MIDP.

Learning curves in laparoscopic distal pancreatectomy: a different experience for each generation

BACKGROUND

Learning curves of laparoscopic distal pancreatectomy (LDP) are mostly based on 'self-taught' surgeons who acquired sufficient proficiency largely through self-teaching. No learning curves have been investigated for 'trained' surgeons who received training and built on the experience of the 'self-taught' surgeons. This study compared the learning curves and outcome of LDP between 'self-taught' and 'trained' surgeons in terms of feasibility and proficiency using short-term outcomes.

MATERIALS AND METHODS

Data of consecutive patients with benign or malignant disease of the left pancreas who underwent LDP by four 'self-taught' and four 'trained' surgeons between 1997 and 2019 were collected, starting from the first patient operated by a contributing surgeon. Risk-adjusted cumulative sum (RA-CUSUM) analyses were performed to determine phase-1 feasibility (operative time) and phase-2 proficiency (major complications) learning curves. Outcomes were compared based on the inflection points of the learning curves.

RESULTS

The inflection points for the feasibility and proficiency learning curves were 24 and 36 procedures for 'trained' surgeons compared to 64 and 85 procedures for 'self-taught' surgeons, respectively. In 'trained' surgeons, operative time was reduced after completion of the learning curves (230.5-203 min, P= 0.028). In 'self-taught' surgeons, operative time (240-195 min, P ≤0.001), major complications (20.6-7.8%, P= 0.008), and length of hospital stay (9-5 days, P ≤0.001) reduced after completion of the learning curves.

CONCLUSION

This retrospective international cohort study showed that the feasibility and proficiency learning curves for LDP of 'trained' surgeons were at least halved as compared to 'self-taught' surgeons.

Transition from open to robotic distal pancreatectomy in a low volume pancreatic surgery country: a single Australian centre experience

BACKGROUND

Advances in technology and techniques have allowed for robotic distal pancreatectomies to be readily performed in patients at high volume centres. This study describes the experience of a single surgeon during the learning curve and transition from open to robotic distal pancreatectomy in Australia, a traditionally low volume pancreatic surgery country.

METHODS

All patients undergoing distal pancreatectomy at an Australian-based tertiary referral centre between 2010 and 2021 were reviewed retrospectively. Demographic, clinicopathologic and survival data were analysed to compare perioperative and oncological outcomes between patients who underwent open, laparoscopic and robotic distal pancreatectomies.

RESULTS

A total of 178 distal pancreatectomies were identified for analysis during the study period. Ninety-one open distal pancreatectomies (ODP), 48 laparoscopic distal pancreatectomies (LDP), and 39 robotic distal pancreatectomies (RDP) were performed. Robotic distal pancreatectomy was non-inferior with respect to perioperative outcomes and yielded statistically non-significant advantages over LDP and ODP.

CONCLUSION

RDP is feasible and can be performed safely in well-selected patients during the learning phase at large pancreatic centres in a traditionally low-volume country like Australia. Referral to large pancreatic centres where access to the robotic platform and surgeon experience is not a barrier, and where a robust multidisciplinary team meeting can take place, remains pivotal in the introduction and transition toward the robotic approach for management of patients with pancreatic body or tail lesions.

Comparison of oncologic outcomes between open and laparoscopic distal pancreatectomy for pancreatic ductal adenocarcinoma using data from the KOTUS-BP national database: overcoming selection bias and the necessity of definite indications

BACKGROUND

Despite the lack of high-level evidence, laparoscopic distal pancreatectomy (LDP) is frequently performed in patients with pancreatic ductal adenocarcinoma (PDAC) owing to advancements in surgical techniques. The aim of this study was to investigate the long-term oncologic outcomes of LDP in patients with PDAC via propensity score matching (PSM) analysis using data from a large-scale national database.

METHODS

A total of 1202 patients who were treated for PDAC via distal pancreatectomy across 16 hospitals were included in the Korean Tumor Registry System-Biliary Pancreas. The 5-year overall (5YOSR) and disease-free (5YDFSR) survival rates were compared between LDP and open DP (ODP).

RESULTS

ODP and LDP were performed in 846 and 356 patients, respectively. The ODP group included more aggressive surgeries with higher pathologic stage, R0 resection rate, and number of retrieved lymph nodes. After PSM, the 5YOSRs for ODP and LDP were 37.3% and 41.4% (p = 0.150), while the 5YDFSRs were 23.4% and 27.2% (p = 0.332), respectively. Prognostic factors for 5YOSR included R status, T stage, N stage, differentiation, and lymphovascular invasion.

CONCLUSION

LDP was performed in a selected group of patients with PDAC. Within this group, long-term oncologic outcomes were comparable to those observed following ODP.

Preoperative biopsy for suspected adenocarcinoma of the pancreatic head: yield and complications

BACKGROUND

Histologic confirmation before pancreaticoduodenectomy (PD) for suspected pancreatic cancer is often performed. We assessed the yield of preoperative biopsy in these patients considering the associated complications.

METHODS

We retrospectively evaluated 216 patients that underwent PD for suspected carcinoma (CA) between 2012 and 2018. Post procedure complications and delay in surgery were assessed, as well as the postoperative diagnosis in relation to preoperative parameters.

RESULTS

Preoperative biopsy was performed in 142 patients (65.7%). Pathologic findings suggestive of CA were found in 106 (74.6%), while benign histology was found in 23 (16.1%), and non-diagnostic findings in 12 (8.4%). Seventy-four patients (34.3%) were operated without a preoperative biopsy. The time from diagnosis to surgery was significantly prolonged in those that underwent biopsy compared to patients that were taken straight to surgery (40±14 versus 18±15 days, P<0.001), and 18 patients (12.6%) suffered from clinically significant post procedure complications. Patients with a preoperative biopsy suggestive of CA, and those that were operated without a preoperative histologic confirmation had comparable rates of CA as a final pathological diagnosis (95.2% and 94.5%, respectively). Nevertheless, in patients with a benign or a non-diagnostic biopsy, the rates of pathologic diagnosis of CA were 69.6% and 73.6% respectively. Elevated levels of CA19-9 and a positive preoperative biopsy were associated with a final pathology of CA.

CONCLUSIONS

Preoperative histology is not uniformly required in patients with suspected pancreatic cancer. If preoperative biopsy is performed, benign histology does not rule out cancer but warrants additional evaluation prior to surgery.

Implementation and training with laparoscopic distal pancreatectomy: 23-year experience from a high-volume center

Background

Distal pancreatectomy is the most common procedure in minimally-invasive pancreatic surgery. Data in the literature suggest that the learning curve flattens after performing up to 30 procedures. However, the exact number remains unclear.

Methods

The implementation and training with laparoscopic distal pancreatectomy (LDP) in a high-volume center were studied between 1997 and 2020. Perioperative outcomes and factors related to conversion were assessed. The individual experiences of four different surgeons (pioneer and adopters) performing LDP on a regular basis were examined.

Results

Six hundred forty LDPs were done accounting for 95% of all distal pancreatectomies performed throughout the study period. Conversion was needed in 14 (2.2%) patients due to intraoperative bleeding or tumor adherence to the major vasculature. Overall morbidity and mortality rates were 35 and 0.6%, respectively. Intra- and postoperative outcomes did not change for any of the surgeons within their first 40 cases. Operative time significantly decreased after the first 80 cases for the pioneer surgeon and did not change afterwards although the proportion of ductal adenocarcinoma increased. Tumor size increased after the first 80 cases for the first adopter without affecting the operative time.

Conclusions

In this nearly unselected cohort, no significant changes in surgical outcomes were observed throughout the first 40 LDPs for different surgeons. The exact number of procedures required to overcome the learning curve is difficult to determine as it seems to depend on patient selection policy and specifics of surgical training at the corresponding center.

Supplementary Information

The online version of this article (10.1007/s00464-021-08306-3) contains supplementary material, which is available to authorized users.

Learning curve of laparoscopic and robotic pancreas resections: a systematic review

BACKGROUND

Minimally invasive pancreatic resection has been shown recently in some randomized trials to be superior in selected perioperative outcomes compared with open resection when performed by experienced surgeons. However, minimally invasive pancreatic resection is associated with a long learning curve. This study aims to summarize the current evidence on the learning curve of minimally invasive pancreatic resection and define the number of cases required to surmount the learning curve.

METHODS

A systematic search was performed on PubMed, Embase, Scopus, and the Cochrane database using a detailed search strategy. Studies that did not describe the learning curve were excluded from the study. Data on the method of learning curve analysis, single surgeon versus institutional learning curve, and outcome measures were extracted and analyzed.

RESULTS

A total of 32 studies were included in the pooled analysis: 12 on laparoscopic pancreatoduodenectomy, 9 on robotic pancreatoduodenectomy, 12 on laparoscopic distal pancreatectomy, and 3 on robotic distal pancreatectomy. Sample population was comparable between laparoscopic pancreatoduodenectomy and robotic pancreatoduodenectomy (median 63 vs 65). Six of 12 studies and 7 of 9 studies used nonarbitrary methods of analysis in laparoscopic pancreatoduodenectomy and robotic pancreatoduodenectomy, respectively. Operating time was used as the single outcome measure in 4 of 12 studies in laparoscopic pancreatoduodenectomy and 5 of 9 studies in robotic pancreatoduodenectomy. Overall, there was no significant difference between the number of cases required to surmount the learning curve for laparoscopic pancreatoduodenectomy versus robotic pancreatoduodenectomy (laparoscopic pancreatoduodenectomy 34.1 [95% confidence interval 30.7-37.7] versus robotic pancreatoduodenectomy 36.7 [95% confidence interval 32.9-41.0]; P = .8241) and laparoscopic distal pancreatectomy versus robotic distal pancreatectomy (laparoscopic distal pancreatectomy 25.3 [95% confidence interval 22.5-28.3] versus robotic distal pancreatectomy 20.7 [95% confidence interval 15.8-26.5]; P = .5997.) CONCLUSION: This study provides a detailed summary of existing evidence around the learning curve in minimally invasive pancreatic resection. There was no significant difference between the learning curve for robotic pancreatoduodenectomy versus laparoscopic pancreatoduodenectomy and robotic distal pancreatectomy versus laparoscopic distal pancreatectomy. These findings were limited by the retrospective nature and heterogeneity of the studies published to date.

Improved oncologic outcomes for minimally invasive left pancreatectomy: Propensity-score matched analysis of the National Cancer Database

BACKGROUND AND OBJECTIVES

Minimally invasive (MIS) left pancreatectomy (LP) is increasingly used to treat pancreatic adenocarcinoma (PDAC). Despite improved short-term outcomes, no studies have demonstrated long-term benefits over open resection.

METHODS

The National Cancer Database was queried between 2010 and 2016 for patients with PDAC, grouped by surgical approach (MIS vs open). Demographics, comorbidities, clinical staging, and pathologic staging were used for propensity-score matching. Perioperative, short-term oncologic, and survival outcomes were compared.

RESULTS

After matching, both cohorts included 805 patients. There were no differences in baseline characteristics, staging, or preoperative therapy between cohorts. The MIS cohort had a shorter length of stay (6.8 ± 5.5 vs 8.5 ± 7.3 days; P < .0001) with the trend toward improved time to chemotherapy (53.9 ± 26.1 vs 57.9 ± 29.9 days; P = .0511) and margin-positive resection rate (15.3% vs 18.9%; P = .0605). Lymph node retrieval and receipt of chemotherapy were similar. The MIS cohort had higher median overall survival (28.0 vs 22.1 months; P = .0067). Subgroup analysis demonstrated the highest survival for robotic compared with laparoscopic and open LP (41.9 vs 26.6 vs 22.1 months; P < .0001).

CONCLUSIONS

This study demonstrates the safety of MIS LP and favorable long-term oncologic outcomes. The improved survival after MIS LP warrants further study with prospective, randomized trials.

Critical Appraisal of the Impact of Individual Surgeon Experience on the Outcomes of Minimally Invasive Distal Pancreatectomies: Collective Experience of Multiple Surgeons at a Single Institution

BACKGROUND

Presently, there are limited studies analyzing the learning experience of minimally invasive distal pancreatectomies (MIDPs) and these frequently focused on a single surgeon or institution learning curve. This study aims to critically analyze the impact of individual surgeon experience on the outcomes of MIDP based on the collective experiences of multiple surgeons at a single institution.

METHODS

A retrospective review of 90 consecutive MIDP from 2006 to 2018 was performed. These cases were performed by 13 surgeons over various time periods. The cohort was stratified into 4 groups according to individual surgeon experience. The case experience of these surgeons was as follows: <5 cases (n=8), 6 to 10 cases (n=2), 11 to 15 cases (n=2), and 30 cases (n=1).

RESULTS

The distribution of the 90 cases were as follows: experience <5 cases (n=44), 6 to 10 cases (n=20), 11 to 15 cases (n=11), and 15 cases (n=15). As individual surgeons gained increasing experience, this was significantly associated with increasingly difficult resections performed, increased frequency of the use of robotic assistance and decreasing open conversion rates (20.5% vs. 100% vs. 9.1% vs. 0%, P=0.038). There was no significant difference in other perioperative outcomes. These findings suggest that the outcomes of MIDP in terms of open conversion rate could be optimized after 15 cases. Subset analyses suggested that the learning curve for MIDP of low difficulty was only 5 cases.

CONCLUSION

MIDP can be safely adopted today and the individual surgeon learning curve for MIDP of all difficulties in terms of open conversion rate can be overcome after 15 cases.

Revisiting the potential advantage of robotic surgical system in spleen-preserving distal pancreatectomy over conventional laparoscopic approach

Background

This study aimed to compare success rate of spleen preservation between robotic and laparoscopic distal pancreatectomy (DP).

Methods

Between November 2007 and March 2018, forty-one patients underwent the conventional laparoscopic DP (Lap group) and the other 37 patients underwent robotic DP (Robot group). The perioperative clinicopathologic variables were compared.

Results

The robotic procedure was chosen by younger patients compared to conventional laparoscopic surgery (42.9±14.0 vs. 51.3±14.6 years, P=0.016). The mean operation time was longer (313 vs. 246 min, P=0.000), but the mean tumor size was smaller in Robot group (2.7±1.2 vs. 4.2±3.3 cm, P=0.018). The overall spleen-preserving rate was higher in the Robot group (91.9% vs. 68.3%, P=0.012). However, with accumulating laparoscopic experiences (after 16th case), the statistical differences in spleen preservation rate between the Robot and Lap groups had diminished (P=0.428).

Conclusions

The present results suggest a robot can be helpful to save the spleen during DP for benign and borderline malignancy. However, a surgeon highly experienced in the laparoscopic approach can also produce a high success rate of spleen preservation, similar to that shown with the robotic approach.

Stepwise implementation of laparoscopic pancreatic surgery. Case series of a single centre's experience

BACKGROUND

Laparoscopic pancreatic surgery still represents a challenge for surgeons. However, in recent decades the experience is expanding. Recent systematic reviews and meta-analyses confirm that laparoscopic pancreatic resection (LPR) is safe, feasible and worthwhile. This study analyses the first 100 consecutive LPRs in our centre.

METHODS

A retrospective analysis was conducted of the first 100 LPRs in a single supra-regional Belgian centre, performed between January 2012 and January 2019. Pre-, peri- and postoperative data were retrieved from a prospectively maintained database. All procedures were performed laparoscopically by two attending surgeons, specialized in minimally invasive and hepatopancreatobiliary surgery.

RESULTS

Of 100 procedures, 62 laparoscopic pancreatoduodenectomies (LPD) and 36 laparoscopic distal pancreatectomies (LDP) were performed, along with 1 enucleation and 1 central pancreatectomy. Indication was malignancy in 70%. Conversion rate was 24,2% in LPD and 11% in LDP. Median operative time was 330 min (IQR 300-360) in LPD and 150 min (IQR 142.5-210) in LDP. Median blood loss was 200 mL (IQR 100-487.5) in LPD and 150 mL (IQR 50-500) in LDP, transfusion rate was 22.6% and 8.3% respectively. Median length of stay (LOS) was 13 days (IQR 10-19.25) in LPD and 9 days (IQR 9-14) in LDP. R0 resection rate was 88.6% (62/70). Major complication rate (Clavien-Dindo grade III-IV) was 12%. Thirty-day mortality was 0%, 90-day mortality was 2%.

CONCLUSION

Our results confirm that LPR is a feasible and safe alternative to open pancreatic surgery. Safe implementation with a clear strategy is fundamental to gain experience and overcome the learning curve of this technically demanding procedures.

Multicentre observational cohort study of implementation and outcomes of laparoscopic distal pancreatectomy

BACKGROUND

Laparoscopic distal pancreatectomy (LDP) is increasingly being performed as an alternative to open surgery. Whether the implementation and corresponding learning curve of LDP have an impact on patient outcome is unknown. The aim was to investigate the temporal trends in practice across UK centres.

METHODS

This was a retrospective multicentre observational cohort study of LDP in 11 tertiary referral centres in the UK between 2006 and 2016. The learning curve was analysed by pooling data for the first 15 consecutive patients who had LDP and examining trends in surgical outcomes in subsequent patients.

RESULTS

In total, 570 patients underwent LDP, whereas 888 underwent open resection. For LDP the median duration of operation was 240 min, with 200 ml blood loss. The conversion rate was 12·1 per cent. Neuroendocrine tumours (26·7 per cent) and mucinous cystic neoplasms (19·7 per cent) were commonest indications. The proportion of LDPs increased from 24·4 per cent in 2006-2009 (P1) to 46·0 per cent in 2014-2016 (P3) (P < 0·001). LDP was increasingly performed for patients aged 70 years or more (16 per cent in P1 versus 34·4 per cent in P3; P = 0·002), pancreatic ductal adenocarcinoma (6 versus 19·1 per cent; P = 0·005) and advanced malignant tumours (27 versus 52 per cent; P = 0·016). With increasing experience, there was a trend for a decrease in blood transfusion rate (14·1 per cent for procedures 1-15 to 3·5 per cent for procedures 46-75; P = 0·008), ICU admissions (32·7 to 19·2 per cent; P = 0·021) and median duration of hospital stay (7 (i.q.r. 5-9) to 6 (4-7) days; P = 0·002). After 30 procedures, a decrease was noted in rates of both overall morbidity (57·7 versus 42·2 per cent for procedures 16-30 versus 46-75 respectively; P = 0·009) and severe morbidity (18·8 versus 9·7 per cent; P = 0·031).

CONCLUSION

LDP has increased as a treatment option for lesions of the distal pancreas as indications for the procedure have expanded. Perioperative outcomes improved with the number of procedures performed.

True learning curve of laparoscopic spleen-preserving distal pancreatectomy with splenic vessel preservation

BACKGROUND

Laparoscopic distal pancreatectomy (LDP) is generally the treatment of choice for diseases of the pancreatic body and tail. Most surgeons prefer the spleen- and splenic vessel-preserving technique (SPVP-LDP) in benign/borderline pancreatic disease because complications of splenic infarction and gastric varices can arise after Warshaw technique. This study was aimed to determine the true learning curve of the SPVP-LDP procedure not LDP including Warshaw technique.

METHODS

Data were collected retrospectively from all patients who underwent a LDP between June 2007 and April 2017 at Gangnam Severance Hospital. We used cumulative sum control chart (CUSUM) analysis to assess the learning curve for the SPVP-LDP technique.

RESULTS

Eight-three patients were performed LDP and we excluded patients who underwent robotic approach (N = 10) and open conversion DP (N = 8). Patients who underwent SPVP-LDP procedures were categorized into Group 1 (primary end-point). Those who underwent LDP procedures with splenectomy and the Warshaw technique were categorized into Group 2. We found that the 16th case was the cutoff point and the mean length of hospital stay was 13.0 days in the first period and 8.7 days in the second period (p = < 0.001).

CONCLUSIONS

These results indicated that the frequency of SPVP-LDPs had increased and that technological progress had been made over time. The true learning curve for SPVP-LDP was indicated as 16 cases in a group of surgeons with no experience of laparoscopic pancreatic surgery.

True learning curve of laparoscopic spleen-preserving distal pancreatectomy with splenic vessel preservation

BACKGROUND

Laparoscopic distal pancreatectomy (LDP) is generally the treatment of choice for diseases of the pancreatic body and tail. Most surgeons prefer the spleen- and splenic vessel-preserving technique (SPVP-LDP) in benign/borderline pancreatic disease because complications of splenic infarction and gastric varices can arise after Warshaw technique. This study was aimed to determine the true learning curve of the SPVP-LDP procedure not LDP including Warshaw technique.

METHODS

Data were collected retrospectively from all patients who underwent a LDP between June 2007 and April 2017 at Gangnam Severance Hospital. We used cumulative sum control chart (CUSUM) analysis to assess the learning curve for the SPVP-LDP technique.

RESULTS

Eight-three patients were performed LDP and we excluded patients who underwent robotic approach (N = 10) and open conversion DP (N = 8). Patients who underwent SPVP-LDP procedures were categorized into Group 1 (primary end-point). Those who underwent LDP procedures with splenectomy and the Warshaw technique were categorized into Group 2. We found that the 16th case was the cutoff point and the mean length of hospital stay was 13.0 days in the first period and 8.7 days in the second period (p = < 0.001).

CONCLUSIONS

These results indicated that the frequency of SPVP-LDPs had increased and that technological progress had been made over time. The true learning curve for SPVP-LDP was indicated as 16 cases in a group of surgeons with no experience of laparoscopic pancreatic surgery.