Long-term Prognosis for Non-functional Neuroendocrine Tumors of the Pancreatic Body and Tail ≤ 3cm

Study Overview
=================
Brief Summary
-----------------
This study aims to quantify the malignant potential of non-functional neuroendocrine tumors of the pancreatic body and tail ≤ 3 cm by collecting real-world data from large pancreatic centers across the country, and to evaluate the appropriateness of parenchyma-sparing resection and oncologic resection.

Detailed Description
-----------------
According to epidemiological investigations, the incidence of neuroendocrine tumors has increased 6.4-fold (6.98 per 100,000) . There is controversy in the latest guidelines regarding the management of sporadic non-functional pancreatic neuroendocrine tumors (pNETs) ≤ 2 cm, including follow-up and the choice between parenchyma-sparing resection (PSR) and oncologic resection (OR) . Although pNETs are generally considered indolent tumors, current experience suggests that 9.5%-12.3% of pNETs ≤ 2 cm may have lymph node metastasis, and nearly 20% of resected tumors exhibit one or more invasive features. Awareness of surgical treatment for these patients has been increasing gradually. However, there is no clear recommendation for the choice of surgical approach, and if OR is routinely performed, its prognostic value is unclear and there may be a risk of overtreatment. The advantages of PSR include preservation of both endocrine and exocrine pancreatic function. However, the main oncological limitations of these techniques are inadequate surgical margin clearance and the risk of lack of lymph node dissection. A recent retrospective analysis of prospective databases from four large pancreatic surgery centers showed that for ≤ 3 cm non-functional pNETs, PSR or lymph node-preserving resection had less blood loss, shorter operation time, lower complications rate, and similar long-term oncological outcomes compared to OR. However, this study did not differentiate the tumor locations, as pNETs in the pancreatic head and body/tail have different lymphatic drainage patterns and surgical approaches. Furthermore, the study also showed significant differences in the proportion of PSR and the rate of positive lymph nodes between tumors located in the pancreatic head and those in the body/tail. The ability of existing literature to provide reliable guidelines for pNETs is limited by the low incidence of the disease and short follow-up times. This study aims to quantify the malignant potential of pNETs of the pancreatic body and tail ≤ 3 cm by collecting real-world data from large pancreatic centers across the country, and to evaluate the appropriateness of PSR and OR.

Official Title
-----------------
Long-term Prognosis Comparison Between Parenchyma-sparing and Oncologic Resections for Non-functional Neuroendocrine Tumors of the Pancreatic Body and Tail ≤ 3cm: a Real-world Data Study

Conditions
-----------------
Non Functioning Pancreatic Endocrine Tumor

Intervention / Treatment
-----------------
* Other: Histopathological review, long-term prognosis and quality of life follow-up


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Non-functional neuroendocrine tumors of the pancreatic body and tail ≤ 3 cm. Exclusion Criteria: Presence of liver or distant metastasis. Presence of concomitant malignancy. Multifocal or recurrent disease. Presence of hereditary syndrome (MEN1, VHL, NF). Presence of symptoms (specific symptoms of clinical syndromes suspected to be related to excessive secretion of bioactive compounds). History of preoperative antitumor therapy. Loss to follow-up.
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Parenchyma-sparing Resections<br>Parenchyma-sparing resections, including open, laparoscopic, or robotic pancreatic enucleation, duodenum-preserving pancreatic head resection, middle segment pancreatectomy, and spleen-preserving distal pancreatectomy, without standard lymph node dissection. | Other: Histopathological review, long-term prognosis and quality of life follow-up<br>* Histopathological review, long-term prognosis and quality of life follow-up<br>|
| Oncologic Resections<br>Oncologic resections, including open, laparoscopic, or robotic pancreaticoduodenectomy or distal pancreatectomy, with standard lymph node dissection. | Other: Histopathological review, long-term prognosis and quality of life follow-up<br>* Histopathological review, long-term prognosis and quality of life follow-up<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival (OS) | The time from the surgery to death from any cause. | Through study completion, an average of 1 year. | 
| Disease-free survival (DFS) | The time of surgery to the time of tumor recurrence or death from any cause. | Through study completion, an average of 1 year. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative complication rate | Adverse events that occur during or after the surgery, including the incidence of postoperative complications reported according to the Clavien-Dindo classification, clinical relevant postoperative pancreatic fistula (POPF), postoperative pancreatic hemorrhage (PPH), delayed gastric emptying (DGE), reoperation rate and mortality rate within 90 days after surgery. | Within 90 days after surgery. | 
| Postoperative pathological staging | The tumor staging according to the 8th edition of the AJCC TNM staging system. | From the date of surgery to 1 month after surgery. | 
| G staging | The G staging evaluated according to the 2019 WHO classification and grading criteria for digestive neuroendocrine tumors. | From the date of surgery to 1 month after surgery. | 
| R0 resection rate | R0 margin rate on postoperative pathological assessment. | From the date of surgery to 1 month after surgery. | 
| Lymph node positivity rate | Lymph node positivity rate on postoperative pathological assessment. | From the date of surgery to 1 month after surgery. | 
| Life quality satisfaction evaluated according to a scale. | The patient's health-related quality of life after surgical intervention. It includes physical, emotional, and social aspects of a patient's well-being. This study evaluated quality of life using a telephone survey. | Through study completion, an average of 1 year. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Non Functioning Pancreatic Endocrine Tumor, Parenchyma-sparing Resection, Oncologic Resection, Long-term Prognosis, Body and Tail of the Pancreas