Value of lymphadenectomy in patients with surgically resected pancreatic neuroendocrine tumors

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are relatively uncommon malignancies, characterized as either functional or nonfunctional secondary to their secretion of biologically active hormones. A wide range of clinical behavior can be seen, with the primary prognostic indicator being tumor grade as defined by the Ki67 proliferation index and mitotic index. Surgery is the primary treatment modality for PNETs. While functional PNETs should undergo resection for symptom control as well as potential curative intent, nonfunctional PNETs are increasingly managed nonoperatively. There is increasing data to suggest small, nonfunctional PNETs (less than 2 cm) are appropriate follow with nonoperative active surveillance. Evidence supports surgical management of metastatic disease if possible, and occasionally even surgical management of the primary tumor in the setting of widespread metastases. In this review, we highlight the evolving surgical management of local and metastatic PNETs.

Use of indocyanine green near-infrared lymphography to detect sentinel lymph nodes in a dog with a malignant insulinoma: a case report

Malignant insulinoma is the most common type of neuroendocrine tumor found in the pancreas of dogs. Canine insulinoma displays malignant behavior with a high rate of metastasis. The most common sites of metastases are the draining lymph nodes, which are also the primary location sites for the recurrence of functional disease. However, identifying metastatic nodes can often be complicated, as the pancreas is drained by numerous lymphatic centers, and clinical enlargement or structural changes may not always be present in metastatic nodes. Additionally, unaltered nodes are frequently small (a few millimeters) and can be hard to distinguish from the surrounding tissues. Therefore, lymphadenectomy is generally recommended for affected dogs. Unlike in human medicine, there are currently no established strategies for lymph node resection in dogs with malignant insulinoma. This report presents a technique for identifying and removing sentinel nodes using indocyanine green and near-infrared lymphography (NIRFL) during surgery. A total of six sentinel nodes were detected and resected with this method. This technique could provide a more structured approach for lymph node resection in affected dogs and potentially in humans in the future. However, its therapeutic benefits must be evaluated in a larger cohort of cases.

Risk Stratification of Pancreatic Neuroendocrine Neoplasms Based on Clinical, Pathological, and Molecular Characteristics

Pancreatic neuroendocrine neoplasms consist of heterogeneous diseases. Depending on the novel features detected by various modern technologies, their classification and related prognosis predictions continue to change and develop. The role of traditional clinicopathological prognostic factors, including classification systems, is also being refined, and several attempts have been made to predict a more accurate prognosis through novel serum biomarkers, genetic factors, and epigenetic factors that have been identified through various state-of-the-art molecular techniques with multiomics sequencing. In this review article, the latest research results including the traditional approach to prognostic factors and recent advanced strategies for risk stratification of pancreatic neuroendocrine neoplasms based on clinical, pathological, and molecular characteristics are summarized. Predicting prognosis through multi-factorial assessments seems to be more efficacious, and prognostic factors through noninvasive methods are expected to develop further advances in liquid biopsy in the future.

Development and validation of nomogram to predict lymph node metastasis preoperatively in patients with pancreatic neuroendocrine tumor

BACKGROUND

Routine lymphadenectomy in pancreatic neuroendocrine tumors (pNETs) is debated. There lacks accurate model to predict lymph node metastasis (LNM) preoperatively in pNETs. Therefore, this study aimed at developing a nomogram in predicting LNM in pNETs preoperatively.

METHODS

Patients undergoing surgery from Surveillance, Epidemiology, and End Results (SEER) database (design cohort, n = 2742) and First Affiliated Hospital of Sun Yat-sen University (validation cohort, n = 136) were enrolled. Nomogram was developed based on risk factors determined by logistic regression analyses. The performance of nomogram was evaluated by area under receiver operating characteristics curve (AUC), calibration curve, and decision curve analysis.

RESULTS

In design cohort, 915 of 2742 patients had LNM. Tumor in the pancreatic head, T stage, and tumor size were significantly associated with LNM (all p < 0.05). Prediction of nomogram was accurate with AUC of 0.776 in design cohort and 0.622 in validation cohort. The nomogram showed good agreement between prediction and observation in the design and validation cohort. Based on nomogram-predicted risk, patients with higher risk of LNM had worse overall survival over patients with lower risk of LNM (log-rank p < 0.001).

CONCLUSIONS

The novel nomogram could accurately predict LNM in pNET preoperatively. For patients with high risk of LNM, lymphadenectomy was recommended.

Clinicopathological characteristics, survival outcomes and prognostic factors in the cT1N0M0 pancreatic neuroendocrine tumors: A SEER-based study

Small nonfunctional pancreatic neuroendocrine tumors ≤2 cm have different biological features, and there is no gold standard treatment for them. This study aimed to assess the risk of malignancy of small non-functional pancreatic neuroendocrine tumors and their outcomes after radical resection. The optimal management of small, incidentally detected pancreatic neuroendocrine tumors is controversial, with the aim of identifying factors predicting survival in patients with clinical stage T1N0M0 (cT1N0M0) pancreatic neuroendocrine tumors and whether surgical treatment improves survival. Using the Surveillance, Epidemiology, and End Results database, we identified 637 patients with cT1N0M0 pancreatic neuroendocrine tumors from 2010 to 2015, including clinicopathological characteristics, treatment modalities, and outcome data. From the surveillance, epidemiology, and end results database of 637 patients with cT1N0M0 PNENs, 564 were treated surgically. Age (P = .000), sex (P < .001), and surgery (P < .001) were independent risk factors affecting survival. Patients who have undergone surgery, women and young adults have a higher overall survival rate. The following independent prognostic predictors for cT1N0M0 pNENs were identified: age, sex, and surgery. At last, we concluded that Surgery can increase the overall survival of pancreatic neuroendocrine tumors in T1N0M0.