Resection of Non-Functional Pancreatic Neuroendocrine Neoplasms-A Single-Center Retrospective Outcome Analysis

Impact of surgical approaches on long-term survival outcomes of patients with pancreatic neuroendocrine carcinoma

Surgery is the primary treatment for pancreatic neuroendocrine carcinoma (PNEC), however, the optimal surgical approach remains undetermined. We aimed to compare long-term survival outcomes between patients who received local resection (LR) and radical resection (RR) for PNEC without distant metastasis. Patients diagnosed with PNEC between 2000 and 2020 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Selection bias was minimized by using propensity score matching (PSM). The Kaplan-Meier method and multivariate Cox proportional hazards models were utilized to evaluate overall survival (OS) and cancer-specific survival (CSS). A total of 1331 patients were enrolled in the study, with 678 receiving LR and 653 undergoing RR. The RR group exhibited a poorer grade, larger tumor size, and TN stage compared to the LR group (P <  0.05). After PSM, 450 matched pairs of patients were compared, with no significant differences in demographic and clinical characteristics observed. No significant differences were observed in long-term OS (P =  0.746) or CSS (P =  0.634) between the two groups. Subgroup analyses also demonstrated comparable OS and CSS between the LR and RR groups (P >  0.05). Multivariate Cox analysis revealed age, AJCC stage, N stage, and chemotherapy as independent prognostic risk factors for OS, while AJCC stage and N stage were identified as independent prognostic risk factors for CSS. Our study demonstrated that in patients with PNEC without distant metastasis, LR and RR exhibit similar prognoses, suggesting that LR may be adequate as a treatment option for these patients.

Comparative Analysis of Complications Following Distal Resections for Neuroendocrine Tumors and Adenocarcinoma: Unveiling the Differences

BACKGROUND Adenocarcinomas and pancreatic neuroendocrine tumors (pNETs) display some similarities and differences. The aim of this study was to compare preoperative data and morphological parameters, and to assess postoperative complications after resection. MATERIAL AND METHODS Data of 162 patients who underwent distal pancreatic resection for neuroendocrine or adenocarcinoma tumor were retrospectively analyzed. After applying inclusion and exclusion criteria, 131 patients were included in the study. The preoperative data analyzed included age, sex, and ASA-PS (American Society of Anesthesiologists Physical Status) grade. The diameter of the pancreatic duct and the texture of the pancreas were analyzed. Postoperative data included grading (G1-G3), the presence of PanIN (pancreatic intraepithelial neoplasia), infiltration of structures, and postoperative complications. RESULTS Patients with adenocarcinoma were statistically older and had a higher ASA-PS class than patients with NET (P<0.001). Statistically significantly more patients with adenocarcinoma had a histopathological diagnosis of G3 (p<0.001). In patients with adenocarcinomas infiltration of structures occurred more frequently. Pancreatic duct diameter ≥3 mm was more common in patients with adenocarcinoma (P=0.045). Clinically significant pancreatic fistulas were more frequent in patients with neuroendocrine tumors (P=0.044). CONCLUSIONS Adenocarcinomas in the pancreatic body and tail are more aggressive, they cause more frequent infiltration of structures, and more often metastasize to lymph nodes compared to NETs. NETs tend to have softer pancreatic texture and higher incidence of clinically significant pancreatic fistulas, but postoperative complications of Clavien-Dindo grade ≥III occur at a similar rate in both groups.

Optimal Lymphadenectomy in Patients with Well-Differentiated Nonfunctioning Pancreatic Neuroendocrine Neoplasms

This study aimed to evaluate the optimal extent of lymphadenectomy in patients with nonfunctioning pancreatic neuroendocrine neoplasms. We retrospectively analyzed the clinicopathological data of patients with nonfunctioning pancreatic neuroendocrine neoplasms who underwent surgical resection. We investigated the frequency of metastases at each lymph node station according to tumor location and analyzed the factors contributing to poor overall survival (OS) and disease-free survival (DFS). Overall, data of 84 patients were analyzed. Among patients with pancreatic head tumors, metastases at stations 8, 13, and 17 were found in one (3.1%), four (12.5%), and three (9.3%) patients, respectively. However, none of the other stations showed metastases. For pancreatic body and tail tumors, metastases only at station 11 were found in two (5.1%) patients. Additionally, multivariate DFS and OS analyses showed that lymph node metastasis was the only independent prognostic factor. In conclusion, lymph node metastasis near the primary tumor was the only independent factor of poor prognosis in patients with nonfunctioning pancreatic neuroendocrine neoplasms after undergoing curative surgery. Peri-pancreatic lymphadenectomy might be recommended for nonfunctioning pancreatic neuroendocrine neoplasms.

Long-term Outcomes of Parenchyma-sparing and Oncologic Resections in Patients With Nonfunctional Pancreatic Neuroendocrine Tumors <3 cm in a Large Multicenter Cohort

INTRODUCTION

The role of parenchyma-sparing resections (PSR) and lymph node dissection in small (<3 cm) nonfunctional pancreatic neuroendocrine tumors (PNET) is unlikely to be studied in a prospective randomized clinical trial. By combining data from 4 high-volume pancreatic centers we compared postoperative and long-term outcomes of patients who underwent PSR with patients who underwent oncologic resections.

METHODS

Retrospective review of prospectively collected clinicopathologic data of patients who underwent pancreatectomy between 2000 and 2021 was collected from 4 high-volume institutions. PSR and lymph node-sparing resections (enucleation and central pancreatectomy) were compared to those who underwent oncologic resections with lymphadenectomy (pancreaticoduodenectomy, distal pancreatectomy). Statistical testing was performed using χ 2 test and t test, survival estimates with Kaplan-Meier method and multivariate analysis using Cox proportional hazard model.

RESULTS

Of 810 patients with small sporadic nonfunctional PNETs, 121 (14.9%) had enucleations, 100 (12.3%) had central pancreatectomies, and 589 (72.7%) patients underwent oncologic resections. The median age was 59 years and 48.2% were female with a median tumor size of 2.5 cm. After case-control matching for tumor size, 221 patients were selected in each group. Patients with PSR were more likely to undergo minimally invasive operations (32.6% vs 13.6%, P <0.001), had less intraoperative blood loss (358 vs 511 ml, P <0.001) and had shorter operative times (180 vs 330 minutes, P <0.001) than patients undergoing oncologic resections. While the mean number of lymph nodes harvested was lower for PSR (n=1.4 vs n=9.9, P <0.001), the mean number of positive lymph nodes was equivalent to oncologic resections (n=1.1 vs n=0.9, P =0.808). Although the rate of all postoperative complications was similar for PSR and oncologic resections (38.5% vs 48.2%, P =0.090), it was higher for central pancreatectomies (38.5% vs 56.6%, P =0.003). Long-term median disease-free survival (190.5 vs 195.2 months, P =0.506) and overall survival (197.9 vs 192.6 months, P =0.372) were comparable. Of the 810 patients 136 (16.7%) had no lymph nodes resected. These patients experienced less blood loss, shorter operations ( P <0.001), and lower postoperative complication rates as compared to patients who had lymphadenectomies (39.7% vs 56.9%, P =0.008). Median disease-free survival (197.1 vs 191.9 months, P =0.837) and overall survival (200 vs 195.1 months, P =0.827) were similar for patients with no lymph nodes resected and patients with negative lymph nodes (N0) after lymphadenectomy.

CONCLUSION

In small <3 cm nonfunctional PNETs, PSRs and lymph node-sparing resections are associated with lower blood loss, shorter operative times, and lower complication rates when compared to oncologic resections, and have similar long-term oncologic outcomes.

Evaluation of Open Surgical and Endovascular Treatment Options for Visceral Artery Erosions after Pancreatitis and Pancreatic Surgery

Purpose: To report and compare the results of endovascular and open surgical treatment for erosion bleeding of visceral arteries following pancreatitis and pancreatic surgery. Materials and Methods: This retrospective study included 65 consecutive patients (46 males, mean age 63 ± 14 years) presenting with visceral artery erosions between January 2011 and December 2020. Endpoints were technical success, freedom from reintervention, stent-graft-related complications, and 30-day and one-year mortality. Results: The causes of erosion bleeding included complications of surgical treatment for the pancreas and upper gastrointestinal tract (75%), pancreatitis (19%), and spontaneous bleeding (6%). Pancreatectomy was performed in 34 (52%) patients, representing 2% of all pancreatectomy procedures (n = 1645) performed in our hospital during the study period. A total of 37 (57%) patients underwent endovascular treatment (EVT), and 28 (43%) patients had open surgery (OS) as a primary treatment. Eight of 37 (22%) patients in the EVT group underwent stent-graft treatment of the eroded vessels and 28 (78%) coil embolization. Six (9%) patients underwent reintervention with no significant differences between EVT and OS groups (11% vs. 7%, p = 0.692). Postoperative morbidity and complications in 52% of all patients were higher in the OS group than in the EVT group (41% vs. 68%, p = 0.029). The in-hospital 30-days mortality rate for all patients was 25%, and it was higher in the OS group than in the EVT group (14% vs. 39%, p = 0.017). Conclusions: An endovascular-first strategy for treating visceral arteries erosions may be preferred to reduce the complications associated with open surgery if patients are hemodynamically stable and have no anastomotic insufficiency. Endovascular treatment may be associated with better in-hospital survival when compared to primary open surgery. Further studies are required to identify the optimal approach.