Predictive Effect of the Total Number of Examined Lymph Nodes on N Staging and Survival in Pancreatic Neuroendocrine Neoplasms

Gastroenteropancreatic neuroendocrine neoplasms: current development, challenges, and clinical perspectives

Neuroendocrine neoplasms (NENs) are highly heterogeneous and potentially malignant tumors arising from secretory cells of the neuroendocrine system. Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are the most common subtype of NENs. Historically, GEP-NENs have been regarded as infrequent and slow-growing malignancies; however, recent data have demonstrated that the worldwide prevalence and incidence of GEP-NENs have increased exponentially over the last three decades. In addition, an increasing number of studies have proven that GEP-NENs result in a limited life expectancy. These findings suggested that the natural biology of GEP-NENs is more aggressive than commonly assumed. Therefore, there is an urgent need for advanced researches focusing on the diagnosis and management of patients with GEP-NENs. In this review, we have summarized the limitations and recent advancements in our comprehension of the epidemiology, clinical presentations, pathology, molecular biology, diagnosis, and treatment of GEP-NETs to identify factors contributing to delays in diagnosis and timely treatment of these patients.

Prognostic Factors of Small Non-Functional Pancreatic Neuroendocrine Tumors and the Risk of Lymph Node Metastasis: A Population-Level Study

BACKGROUND

Small non-functional neuroendocrine tumors (NF-PNETs) are a heterogeneous subset of tumors with controversy regarding their optimal management. We aimed to analyze the prognostic factors of patients with small NF-PNETs and create a risk score for lymph node metastasis (LNM).

METHODS

Data of 751 patients with NF-PNETs ≤ 2 cm were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate survival analysis was performed to analyze the prognostic factors. Logistic regression was used to identify risk factors for LNM.

RESULTS

Of the 751 patients, 99 (13.2%) were confirmed to have LNM. In multivariate survival analysis, LNM (hazard ratio [HR], 2.12; 95% CI, 1.04-4.32, p = 0.040) was independently associated with disease-specific survival. Logistic regression identified that tumor location in the head of the pancreas (odds ratio [OR], 4.33; 95% CI, 2.75-6.81; p < 0.001), size ≥ 1.5-2 cm (OR, 1.84; 95% CI, 1.17-2.87; p = 0.009), and grade III-IV (OR, 7.90; 95% CI, 1.79-34.90; p = 0.006) were independent risk factors of LNM. According to the OR value, the risk of LNM was scored as follows: a score of 1 for tumors located in the body/tail of the pancreas and 4 for those located in the head; a score of 1 for tumors <1 cm and 2 for those ≥1.5-2 cm; and a score of 1 for tumors with grade I-II and 8 for those with grade III-IV. Finally, the median score for this cohort was 4, with an interquartile range of 3-6. Therefore, patients were classified as three groups based on the risk score system: a total score of 1-3 for low risk, 4-6 for intermediate risk (OR, 2.98; 95% CI, 1.59-5.60; p = 0.001), and 7-14 for high risk (OR, 8.94; 95% CI, 4.50-17.7; p < 0.001), with an incidence of LNM 5.0%, 13.5%, and 31.8%, respectively (p < 0.001).

CONCLUSION

Surgical resection with regional lymphadenectomy is recommended for small NF-PNETs with malignant potential of LNM. A risk score for LNM based on tumor grade, location, and size may preoperatively predict LNM of small NF-PNETs and guide clinical practice.

Identifying Risk Factors and Patterns for Early Recurrence of Pancreatic Neuroendocrine Tumors: A Multi-Institutional Study

Simple Summary

Approximately 30% of patients with a pancreatic neuroendocrine tumor (pNET) will develop metastases. Curative-intent treatment largely involves resection. Identifying patients with early recurrence (ER) following resection might help tailor adjuvant therapies and the surveillance intensity. The aim of this retrospective study was to determine an evidence-based cut-off value for ER, and to explore risk factors associated with ER. ER was identified 18 months after surgery. Tumor size (OR 1.20, 95% CI 1.05–1.37, p = 0.007) and positive lymph nodes (OR 4.69, 95%CI 1.41–15.58, p = 0.01) were independently associated with ER. Patients with ER had lower post-recurrence free survival and overall survival than patients with late recurrence. These data support intensive follow-up shortly after surgery, and adjuvant therapy may help improve survival in pNET patients with ER after surgery.

Abstract

Background: Identifying patients at risk for early recurrence (ER) following resection for pancreatic neuroendocrine tumors (pNETs) might help to tailor adjuvant therapies and surveillance intensity in the post-operative setting. Methods: Patients undergoing surgical resection for pNETs between 1998–2018 were identified using a multi-institutional database. Using a minimum p-value approach, optimal cut-off value of recurrence-free survival (RFS) was determined based on the difference in post-recurrence survival (PRS). Risk factors for early recurrence were identified. Results: Among 807 patients who underwent curative-intent resection for pNETs, the optimal length of RFS to define ER was identified at 18 months (lowest p-value of 0.019). Median RFS was 11.0 months (95% 8.5–12.60) among ER patients (n = 49) versus 41.0 months (95% CI: 35.0–45.9) among non-ER patients (n = 77). Median PRS was worse among ER patients compared with non-ER patients (42.6 months vs. 81.5 months, p = 0.04). On multivariable analysis, tumor size (OR: 1.20, 95% CI: 1.05–1.37, p = 0.007) and positive lymph nodes (OR: 4.69, 95% CI: 1.41–15.58, p = 0.01) were independently associated with ER. Conclusion: An evidence-based cut-off value for ER after surgery for pNET was defined at 18 months. These data emphasized the importance of close follow-up in the first two years after surgery.

Multiple endocrine neoplasia type 1 (MEN-1) and neuroendocrine neoplasms (NENs)

Neuroendocrine neoplasms (NENs) are relatively rare neoplasms with 6.4-times increasing age-adjusted annual incidence during the last four decades. NENs arise from neuroendocrine cells, which release hormones in response to neuronal stimuli and they are distributed into organs and tissues. The presentation and biological behaviour of the NENs are highly heterogeneous, depending on the organ. The increased incidence is mainly due to increased awareness and improved detection methods both in the majority of sporadic NENs (non-inherited), but also the inherited groups of neoplasms appearing in at least ten genetic syndromes. The most important one is multiple endocrine neoplasia type 1 (MEN-1), caused by mutations in the tumour suppressor gene MEN1. MEN-1 has been associated with different tumour manifestations of NENs e.g. pancreas, gastrointestinal tract, lungs, thymus and pituitary. Pancreatic NENs tend to be less aggressive when arising in the setting of MEN-1 compared to sporadic pancreatic NENs. There have been very important improvements over the past years in both genotyping, genetic counselling and family screening, introduction and validation of various relevant biomarkers, as well as newer imaging modalities. Alongside this development, both medical, surgical and radionuclide treatments have also advanced and improved morbidity, quality of life and mortality in many of these patients. Despite this progress, there is still space for improving insight into the genetic and epigenetic factors in relation to the biological mechanisms determining NENs as part of MEN-1. This review gives a comprehensive update of current evidence for co-occurrence, diagnosis and treatment of MEN-1 and neuroendocrine neoplasms and highlight the important progress now finding its way to international guidelines in order to improve the global management of these patients.

Epidemiologic trends and prognostic risk factors of patients with pancreatic neuroendocrine neoplasms in the US: an updated population-based study

Background: We aimed to evaluate the incidence, mortality and survival outcome for patients with pancreatic neuroendocrine neoplasms (pNEN). Methods: Patients with pNEN were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Incidence, mortality and average annual percentage change (AAPC) were calculated using SEER stat 8.3.6 and Joinpoint software. Survival outcome was estimated using Kaplan-Meier and Cox proportional hazard model. Results: During 2000-2016, the incidence of pNEN significantly rose from 0.2647 to 1.0618 per 100,000 persons with an AAPC of 9.4; AAPC of mortality was 6.7. Prognostic improvement was revealed in 2010-2016, but not for late-stage pNEN, which had the highest risk of death. Conclusion: Efforts to improve prognosis of pNEN patients must focus on not only early detection, but also on improving therapy for late-stage disease.

M6A Regulatory Genes Play an Important Role in the Prognosis, Progression and Immune Microenvironment of Pancreatic Adenocarcinoma

The specific roles of N6-methyladenosine (m6A) regulatory genes in pancreatic adenocarcinoma (PAAD) have not been fully elucidated. In present study, a novel risk signature was constructed by five m6A-related genes (including METTL3, METTL14, KIAA1429, ALKBH5 and YTHDF1) and was identified as an independent prognostic factor (HR = 13.192) via TCGA (185 samples) databases. The immune abundances of 22 leukocyte subtypes in each PAAD sample were exhibited via the CIBERSORT algorithm. High risk group promoted infiltration levels of Macrophages M0 and M2 cells and decreased that of B cells naive, T cells CD8 and T regulatory cells.

Comparison of morphological features in lymph node metastasis between pancreatic neuroendocrine neoplasms and pancreatic ductal adenocarcinomas

BACKGROUND

Various studies have reported inconsistent results regarding the use of lymph node size for the prediction of metastasis in pancreatic cancer. Further, there is even less information in pNENs. Thus, the clinical accuracy and utility of using lymph node size to predict lymph node metastasis in pNENs has not been fully elucidated OBJECTIVES: This study aimed to examine differences in lymph node morphology between pancreatic neuroendocrine neoplasms (pNENs) and pancreatic ductal adenocarcinomas (PDACs) to create more accurate diagnostic criteria for lymph node metastasis.

METHODS

We assessed 2139 lymph nodes, 773 from pNEN specimens and 1366 from PDAC specimens, surgically resected at our institute between 1994 and 2016. We evaluated the number, shape, size, and presence of metastasis.

RESULTS

Sixty-eight lymph nodes from 16 pNEN patients and 109 lymph nodes from 33 PDAC patients were metastatic. There were more lymph nodes sampled per case in the PDAC group than in the pNEN group (31.8 vs. 18.0). Metastatic lymph nodes in pNEN patients were larger and rounder than those in PDAC patients (minor axis: 5.15 mm vs. 3.11 mm; minor axis/major axis ratio: 0.701 vs. 0.626). The correlation between lymph node size and metastasis was stronger in pNENs (r = 0.974) than in PDACs (r = 0.439).

CONCLUSIONS

Lymph node status and morphology are affected by differences in tumor histology. The lymph node minor axis is a reliable parameter for the prediction of lymph node metastasis and has more utility as a predictive marker in pNENs than in PDACs.

Prognostic and predictive factors on overall survival and surgical outcomes in pancreatic neuroendocrine tumors: recent advances and controversies

Introduction: Recent advances in diagnostic modalities and therapeutic agents have raised the importance of prognostic factors in predicting overall survival, as well as predictive factors for surgical outcomes, in tailoring therapeutic strategies of patients with pancreatic neuroendocrine neoplasms (panNENs).Areas covered: Numerous recent studies of panNEN patients report the prognostic values of a number of clinically related factors (clinical, laboratory, imaging, treatment-related factors), pathological factors (histological, classification, grading) and molecular factors on long-term survival. In addition, an increasing number of studies showed the usefulness of various factors, specifically biomarkers and molecular makers, in predicting recurrence and mortality related to surgical treatment. Recent findings (from the last 3 years) in each of these areas, as well as recent controversies, are reviewed.Expert commentary: The clinical importance of prognostic and predictive factors for panNENs is markedly increased for both overall outcome and post resection, as a result of recent advances in all aspects of the diagnosis, management and treatment of panNENs. Despite the proven prognostic utility of routinely used tumor grading/classification and staging systems, further studies are required to establish these novel prognostic factors to support their routine clinical use.

Laparoscopic pancreaticoduodenectomy: are the best times coming?

Background

The introduction of laparoscopic technology has greatly promoted the development of surgery, and the trend of minimally invasive surgery is becoming more and more obvious. However, there is no consensus as to whether laparoscopic pancreaticoduodenectomy (LPD) should be performed routinely.

Main body

We summarized the development of laparoscopic pancreaticoduodenectomy (LPD) in recent years by comparing with open pancreaticoduodenectomy (OPD) and robotic pancreaticoduodenectomy (RPD) and evaluated its feasibility, perioperative, and long-term outcomes including operation time, length of hospital stay, estimated blood loss, and overall survival. Then, several relevant issues and challenges were discussed in depth.

Conclusion

The perioperative and long-term outcomes of LPD are no worse and even better in length of hospital stay and estimated blood loss than OPD and RPD except for a few reports. Though with strict control of indications, standardized training, and learning, ensuring safety and reducing cost are still and will always the keys to the healthy development of LPD; the best times for it are coming.

Pituitary adenomas in patients with multiple endocrine neoplasia type 1: a single-center experience in China

PURPOSE

To explore the clinical characteristics of pituitary adenomas in patients with MEN1 and to summarize treatment strategies for MEN1 in a Chinese population.

METHODS

We retrospectively analyzed 54 MEN1 patients with pituitary adenomas diagnosed at Peking Union Medical College Hospital from March 2003 to January 2017. Clinical data, laboratory testing results, treatments of involved glands and treatment responses were collected and analyzed.

RESULTS

The mean age at pituitary adenoma diagnosis was 53.9 ± 17.8. The patients initially consulted the Endocrinology, General Surgery and Neurosurgery departments, in descending frequency. The nonfunctioning adenoma, prolactinoma, GH-secreting adenoma, cosecreting adenoma, and ACTH-secreting adenoma subtypes accounted for 48.1%, 27.8%, 9.3%, 9.3% and 5.6% of the cases, respectively. The remission rate for prolactinomas was 46.2% (6/13) treated with bromocriptine. And the remission rates were 87.5% (7/8) and 100% (3/3) for GH-secreting adenomas and ACTH-secreting adenomas respectively achieved by transsphenoidal surgery. Nineteen (35.2%) patients with asymptomatic nonfunctioning pituitary adenomas showed no progression after a 35-month follow-up with close observation. Regarding treatment priority, patients with thymic carcinoid tumors received first-line surgery, 54% of the patients with enteropancreatic tumors had these tumors treated first, and 26% of all patients had their pituitary adenomas treated first. In acromegalic patients, pituitary lesions tended to be treated first (75%, p = 0.002). PHPT and adrenocortical adenomas can be managed with elective surgery.

CONCLUSIONS

The treatment of MEN1 requires cooperation between multidisciplinary teams. Individualized treatment according to the severity of glandular involvement is needed. GH-secreting and ACTH-secreting pituitary adenomas require active treatment, while nonfunctioning pituitary adenomas can be observed closely.

Sporadic pancreatic neuroendocrine tumor: Surgery of the primary tumor

The management of patients with sporadic pancreatic neuroendocrine tumors (PNET) is multi-disciplinary and often, multimodal. Surgery has a large part in treatment because it is the only potentially curative therapeutic modality if resection can be complete. The update reviews the operative indications and the different surgical techniques available (including parenchymal-sparing surgery) to treat the primary lesion according to patient status, preoperative work-up and whether the tumor is functioning or not. The place of observation for "small" non-functional sporadic PNET is also discussed.