Posterior enucleation of the pancreatic head: an alternative route of access for parenchyma-sparing pancreatic resection

Laparoscopic pancreatic enucleation: how far should we go for parenchyma preservation? A study by the French National Association of Surgery

BACKGROUND

Pancreatic enucleation is indicated for selected patients and tumours with very low oncological risk to preserve a maximum of healthy pancreatic parenchyma. Minimally invasive pancreatic enucleation (MIPE) is increasingly performed. This study aims to assess the impact of tumor location and center experience on textbook outcomes (TBO) in patients undergoing MIPE.

METHODS

Retrospective nationwide multicentric cohort study including MIPE performed between 2010 and 2021. Tumor localization was classified as head/uncus, neck or body/tail (results are presented in this order). Centers were classified according to a mean volume of MI pancreatectomies performed per year: lower (< 5/year), intermediate (5 to 10/year) and higher volume (≥ 10/year). TBO was defined as meeting all 6 criteria: no postoperative pancreatic fistula (POPF), no post-pancreatectomy haemorrhage (PPH), no bile leak, no readmission, no mortality, and no severe morbidity.

RESULTS

27 participating centers performed 200 MIPE located in head/uncus (n = 65, 33%), neck (n = 26, 13%) and body/tail (n = 109, 55%), 8% of them performed by robotic approach. Mortality reached 1.5% (n = 3). Head/uncus lesions were larger (p = 0.03), frequently BD-IPMN (p = 0.04), with significant longer operative time (p = 0.002). TBO achievement was high across all tumor locations (52 vs. 73 vs. 67%, p = 0.09) with higher PPH (p = 0.03) or bile leaks (p = 0.03) for head/uncus lesions. In multivariate analysis, overweight (OR 0.49), preoperative biopsy (OR 0.41) and head/uncus lesion (OR 0.34) were independently associated with lower TBO. No independent risk factor was found for POPF or severe morbidity. While expertise level influenced indications, with more cystic lesions (p = 0.002), larger tumors (p = 0.003), 3D use (p = 0.001), and head/uncus lesions (p = 0.04) in high volume centers, TBO was not significantly different (p = 0.45).

CONCLUSIONS

MIPE is feasible with 1.5% mortality whatever its localization with higher morbidity for head/uncus lesions, justified by the will to avoid pancreaticoduodenectomy. High volume centers push the limits of MIPE without increasing morbidity.

Robotic-assisted pancreatic enucleation: Posterior uncinate approach

Functional pancreatic neuroendocrine tumors (pNET) necessitate surgical resection. Enucleation is the preferred surgical method for well-differentiated pNETs that measure less than 2 cm in diameter, as it offers a greater likelihood of enhancing post-operative recovery and decreasing morbidity and mortality. Insulinomas are particularly suitable for enucleation when such a procedure is viable. However, enucleating tumors within the uncinate process of the pancreas, especially on its posterior aspect, can present substantial challenges. The accompanying video illustrates a robotic-assisted enucleation of an insulinoma in the uncinate process, performed on a 41-year-old male with recurrent hypoglycemia. This intervention led to the resolution of symptoms and incurred minimal post-operative morbidity.

Solid Pseudopapillary Tumor of the Pancreas: Is Enucleation Safe?

BACKGROUND

While solid pseudopapillary tumor (SPT) of the pancreas are oncologically low-risk tumors, their resection with pancreaticoduodenectomy (PD) or partial pancreatectomy (PP) carries a significant risk for morbidity. To balance the favorable prognosis with the surgical morbidity of pancreas resection, this study explores the oncologic safety of enucleation (EN).

PATIENTS AND METHODS

The National Cancer Database (NCDB) was queried for resected SPT from January 2004 through December 2020. Perioperative outcomes and survival were analyzed with Kruskal-Wallis tests, and Kaplan-Meier analysis (with log-rank test). Survival analysis was performed to compare patients with and without lymph node (LN) metastases and binary logistic regression for predictors of LN metastasis.

RESULTS

A total of 922 patients met inclusion criteria; 18 patients (2%) underwent EN, 550 (59.6%) underwent PP, and 354 (38.4%) underwent PD. Mean tumor size was 57.6 mm. Length of hospital stay was significantly shorter for EN compared with PP and PD groups (3.8 versus 6.2 versus 9.4 days, p < 0.001). There was a nonsignificant improvement in unplanned readmission [0% versus 8% versus 10.7% (p = 0.163)], 30-day mortality [0% versus 0.5% versus 0% (p = 0.359)], and 90-day mortality [0% versus 0.5% versus 0% (p = 0.363)] between EN, PP, and PD groups. Survival analyses showed no difference in OS when comparing EN versus PP (p = 0.443), and EN versus PD (p = 0317). Patients with LN metastases (p < 0.001) fared worse, and lymphovascular invasion, higher T category (T3-4) and M1 status were found as predictors for LN metastasis.

CONCLUSIONS

EN may be considered for select patients leading to favorable outcomes. Because survival was worse in the rare cohort of patients with LN metastases, the predictors for LN metastasis identified here may aid in stratifying patients to EN versus resection.

Reconsidering the role of prophylactic pancreaticojejunostomy in pancreatic enucleation: balancing the benefits and risks

BACKGROUND

The incidence of postoperative pancreatic fistula (POPF) following enucleation is high, and prophylactic pancreaticojejunostomy (PPJ) is frequently performed. Minimally invasive enucleation (MEN) has been demonstrated to be safe and feasible, leaving most enucleation wounds exposed.

METHODS

The clinical data of 40 patients who underwent open enucleation with PPJ at our center between 2012 and 2021 were compared with those of 80 patients who underwent MEN.

RESULTS

The MEN group had better outcomes than the PPJ group in terms of intraoperative bleeding (50.0 versus 100.0 mL), postoperative semi-liquid diet recovery (2.0 versus 5.0 days), and postoperative length of stay (7.7 versus 12.5 days). While the MEN group had higher rates of complex enucleation (60.0% versus 40.0%), main pancreatic duct repair (32.5% versus 10.0%), discharge with drains (48.8% versus 25.0%), and grade B POPFs (47.5% versus 17.5%). Both surgical methods effectively preserved pancreatic function; however, two patients in the PPJ group experienced severe haemorrhaging and died. Additionally, during the follow-up period, gastrointestinal bleeding was found and discomfort in the surgical area was reported.

CONCLUSION

Pancreatic enucleation combined with PPJ should be avoided, and although a biochemical or grade B POPF may develop after MEN, it can be compensated for by preserving pancreatic function and ensuring a good long-term quality of life in the patients.

Impact of parenchyma-preserving surgical methods on treating patients with solid pseudopapillary neoplasms: A retrospective study with a large sample size

BACKGROUND

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm that mainly affects young women.

AIM

To evaluate the impact of parenchyma-preserving surgical methods (PPMs, including enucleation and central pancreatectomy) in the treatment of SPN patients.

METHODS

From 2013 to 2019, patients who underwent pancreatectomy for SPNs were retrospectively reviewed. The baseline characteristics, intraoperative index, pathological outcomes, short-term complications and long-term follow-up data were compared between the PPM group and the conventional method (CM) group.

RESULTS

In total, 166 patients were included in this study. Of them, 33 patients (19.9%) underwent PPM. Most of the tumors (104/166, 62.7%) were found accidentally. Comparing the parameters between groups, the hospital stay d (12.35 vs 13.5 d, P = 0.49), total expense (44213 vs 54084 yuan, P = 0.21), operation duration (135 vs 120 min, P = 0.71), and intraoperative bleeding volume (200 vs 100 mL, P = 0.49) did not differ between groups. Regarding pathological outcomes, tumor size (45 vs 32 mm, P = 0.07), Ki67 index (P = 0.53), peripheral tissue invasion (11.3% vs 9.1%, P = 0.43) and positive margin status (7.5% vs 6%, P = 0.28) also did not differ between groups. Moreover, PPM did not increase the risk of severe postoperative pancreatic fistula (3.8% vs 3.0%, P = 0.85) or tumor recurrence (3.0% vs 6.0%, P = 0.39). However, the number of patients who had exocrine insufficiency during follow-up was significantly lower in the PPM group (21.8% vs 3%, P = 0.024). CM was identified as an independent risk factor for pancreatic exocrine insufficiency (odds ratio = 8.195, 95% confident interval: 1.067-62.93).

CONCLUSION

PPM for SPN appears to be feasible and safe for preserving the exocrine function of the pancreas.

Image-guided minimally invasive endopancreatic surgery using a computer-assisted navigation system

BACKGROUND

Minimally invasive endopancreatic surgery (EPS), performing a pancreatic resection from inside the pancreatic duct, has been proposed as an experimental alternative to duodenum-preserving pancreatic head resection in benign diseases such as chronic pancreatitis, but is complicated by difficult spatial orientation when trying to reach structures of interest. This study assessed the feasibility and potential benefits of image-guided EPS using a computer-assisted navigation system in artificial pancreas silicon model.

METHODS

A surgical navigation system displayed a 3D reconstruction of the original computed tomography (CT) scan and the endoscope in relation to a selected target structure. In a first step, different surface landmark (LM)-based and intraparenchymal LM-based approaches for image-to-physical space registration were evaluated. The accuracy of registration was measured as fiducial registration error (FRE). Subsequently, intrapancreatic lesions (n = 8) that were visible on preoperative imaging, but not on the endoscopic view, were targeted with a computer-assisted, image-guided endopancreatic resection technique in pancreas silicon models. After each experiment, a CT scan was obtained for measurement of the shortest distance from the resection cavity to the centre of the lesion.

RESULTS

Intraparenchymal LM registration [FRE 2.24 mm (1.40-2.85)] was more accurate than surface LM registration [FRE 3.46 mm (2.25-4.85); p = 0.035], but not more accurate than combined registration of intraparenchymal and surface LM [FRE 2.46 mm (1.60-3.35); p = 0.052]. Using image-guided EPS, six of seven lesions were successfully targeted. The median distance from the resection cavity to the centre of the lesion on CT was 1.52 mm (0-2.4). In one pancreas, a lesion could not be resected due to the fragility of the pancreas model.

CONCLUSION

Image-guided minimally invasive EPS using a computer-assisted navigation system enabled successful targeting of pancreatic lesions that were invisible on the endoscopic image, but detectable on preoperative imaging. In the clinical setting, this tool could facilitate complex minimally invasive and robotic pancreatic procedures.