The number of positive lymph node is a better predictor of survival than the lymph node metastasis status for pancreatic neuroendocrine neoplasms: A retrospective cohort study

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.

Recurrence after surgical resection of nonmetastatic sporadic gastrinoma: Which prognostic factors and surgical procedure?

BACKGROUND

The only curative treatment of gastrinoma is complete resection, but its surgical management remains controversial and prognostic factors of sporadic nonmetastatic gastrinoma are poorly known.

METHODS

This was a retrospective study including all patients who underwent elective surgery for nonmetastatic sporadic gastrinoma between 2000 and 2020 in 15 hospitals. The primary and secondary outcomes were overall survival and disease-free survival predictive factors.

RESULTS

In total, 108 patients were included, of which 68 (63%) were duodenal, 19 (18%) pancreatic, and 21 (19%) primary lymph node gastrinomas, with no major difference in clinical presentation. Among the 68 duodenal gastrinomas, 26% (n = 18) underwent pancreaticoduodenectomy (PD) and 74% (n = 50) underwent duodenotomy with the excision of duodenal wall tumors and lymphadenectomy (DUODX + LN). Overall, the median overall survival was 173 months, and the 5-year overall survival was 94%, with no predictive factors identified. The median disease-free survival was 93 months, and the 5-year disease-free survival was 63%. Tumor size >2 cm (P = .00001), grade (P = .00001), and pancreatic tumor location (P = .0001) were predictive factors of recurrence; however, in multivariate analysis, only tumor size >2 cm (P = .005) and grade (P = .013) were independent predictors of recurrence. Age, sex, preoperative gastrin level, lymphadenectomy <10 resected lymph nodes, and metastatic lymph nodes on surgical specimens were not predictors of recurrence. For duodenal gastrinomas, surgical procedures (PD versus DUODX + LN) did not have a significant effect on overall survival and disease-free survival.

CONCLUSION

Sporadic nonmetastatic gastrinomas had an excellent overall survival. Recurrence is frequent and influenced by tumor size and grade. Regarding sporadic duodenal gastrinoma, duodenotomy with excision of duodenal wall tumors with lymphadenectomy could be considered a valid surgical option, in the absence of clear oncologic superiority of PD.

A Nomogram to Accurately Identify Pancreatic Neuroendocrine Tumors Metastasizing to Distant Organs: A Study Based on Two National Population-Based Cohorts From the United States and China

Background:

Distant organ metastasis is the leading cause of death in pancreatic neuroendocrine tumor (pNET) patients. In the present study, we aimed to develop and validate a nomogram that could accurately identify pNET metastasizing to distant organs.

Methods:

The cases extracted from the Surveillance, Epidemiology, and End Results (SEER) program were assigned to the training cohort and validation cohort. The cases from the Chinese Gastrointestinal Neuroendocrine Tumors program were assigned to the external validation cohort. The strategy was developed with the support of a nomogram, and the predictive value of this strategy was evaluated by the receiver operating characteristic (ROC) curve analysis.

Results:

In total, 2024 American cases were involved in the present study. Besides, 1450 and 574 patients were allocated into training and internal validation cohorts, respectively. In addition, 122 Chinese patients were assigned to the external validation cohort. The results of the univariate logistic regression analysis suggested that tumor grade, tumor size, and the number of metastatic lymph nodes were the risk of metastasis to distant organs, and these 3 clinicopathological characteristics were used to develop the nomogram. We observed that the accuracy of the nomogram for predicting metastasis to distant organs was 0.797, 0.819, and 0.837 in the training cohort, internal validation cohort, and external validation cohort, respectively.

Conclusions:

A predictive nomogram was developed and validated, and it showed an acceptable performance in predicting metastasis to distant organs. The results will enable clinicians to identify pNETs, metastasizing to distant organs, and develop an effective individualized therapeutic strategy for these patients.

CT features predictive of nodal positivity at surgery in pancreatic cancer patients following neoadjuvant therapy in the setting of dual energy CT

PURPOSE

Evaluate utility of dual energy CT iodine material density images to identify preoperatively nodal positivity in pancreatic cancer patients who underwent neoadjuvant therapy.

METHODS

This IRB approved retrospective study evaluated 62 patients between 2012 and 2016 with proven pancreatic ductal adenocarcinoma, who underwent neoadjuvant therapy, tumor resection and both baseline and preoperative assessment with pancreatic multiphasic rapid switching dual energy CT. Three radiologists in consensus identified on imaging nodes > 0.5 cm in short axis, evaluated nodal morphology, size and on each phase density in HU, and concentrations on iodine material density images normalized to the aorta.

RESULTS

Of 62 patients, 33 were N0, 20 N1, and 9 N2. Total of 145 lymph nodes were evaluated, with average number of nodes per anatomic site ranging from 1.3 (body tumors) to 5 (uncinate) versus average of 24 and 30 nodes recovered respectively at surgery. Most (N = 44) were pancreatic head tumors. For all patients, regardless of site of primary tumor, the minimum measured iodine value of all of a patient's measured nodes taken as a group on preoperative studies, as normalized to the aorta, was significant at P = 0.041 value in differentiating N0 from N1/2 and ROC analysis showed an AUC of 0.67. With a cutoff of 0.2857, sensitivity was 0.78 and specificity was 0.58, with values < 0.2857 indicative of N1/2. Node morphology and changes in nodal size weren't statistically significant.

CONCLUSION

The dual energy based minimum normalized iodine value of all nodes in the surgical field on preoperative studies has modest utility in differentiating N0 from N1/2, and generally outperformed conventional features for identifying nodal metastases.

The eighth version of American Joint Committee on Cancer nodal classification for high grade pancreatic neuroendocrine tumor should be generalized for the whole population with this disease

Several indexes evaluating the lymph node metastasis of pancreatic neuroendocrine tumor (pNET) have been raised. We aimed to compare the prognostic value of the indexes via the analysis of Surveillance, Epidemiology, and End Results (SEER) database.We identified pNETs patients from SEER database (2004-2015). The prognostic value of N classification which adopted the 8th American Joint Committee on Cancer (AJCC) N classification for well differentiated pNET, revised N classification (rN) which adopted the AJCC 8th N classification for exocrine pancreatic cancer (EPC) and high grade pNET, lymph node ratio and log odds of positive nodes were analyzed.A total of 1791 eligible patients in the SEER cohort were included in this study. The indexes N, rN, lymph node ratio, and log odds of positive nodes were all significant independent prognostic factors for the overall survival. Specifically, the rN had the lowest akaike information criterion of 4050.19, the highest likelihood ratio test (χ) of 48.87, and the highest C-index of 0.6094. The rN was significantly associated with age, tumor location, tumor differentiation, T classification and M classification (P < .05 for all).The 8th version of AJCC N classification for high grade pNET could be generalized for the pNET population.

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.

The Number of Metastatic Lymph Nodes is a Useful Predictive Factor for Recurrence after Surgery for Nonmetastatic Nonfunctional Neuroendocrine Neoplasm of the Pancreas

Nodal involvement (actually categorized as positive or negative) is an important prognostic factor after surgery for pancreatic neuroendocrine neoplasms (pNENs). We aim to evaluate the predictive role of the number of nodal metastases after pancreatic resection for pNENs. We analyzed from a prospectively maintained database all pancreatic resections for nonmetastatic nonfunctioning pNENs performed in our institution from 2011 to 2016. According to the number of nodal metastases, enhancing the actual categorization, we distinguished the following: N0, no nodal metastases; N1, 1-3 metastatic lymph nodes; and N2, metastases in 4 or more regional lymph nodes. Recurrence and disease-free survival (DFS) were evaluated. The predictive value in terms of recurrence for each clinicopathological data, including the number of metastatic lymph nodes, was calculated. Univariate and multivariate analyses were conducted. 77 patients underwent pancreatic surgery for pNENs. N0, N1, and N2 resections were found in 52 (67.5%), 16 (20.8%), and 9 (11.7%) cases, respectively. Mean follow-up of the entire cohort was 48 (±25) months. The recurrence rate was 11.8%, and the mean time of recurrence was 12 (±14) months. DFS was 83.7 months (76.0 - 91.5). At a univariate analysis, factors associated with recurrence were mitotic count (OR 1.19, p = 0.001), Ki67 value (OR 1.06, p = 0.001), the presence of nodal metastases (OR 11.54, p = 0.002), and metastases in 4 or more regional lymph nodes (N2) (OR 30.19, p = 0.002). At a multivariate analysis, only mitotic count (OR 1.51, p = 0.005) and N2 resection (OR 134.74, p = 0.002) were found to be predictive factors of recurrence. The number of metastatic lymph nodes and mitotic count is the most significant predictive factors of recurrence after pancreatic surgery for nonmetastatic nonfunctioning pNENs.

A modified M-stage classification based on the metastatic patterns of pancreatic neuroendocrine neoplasms: a population-based study

BACKGROUND

The present study aims to improve the M-stage classification of pancreatic neuroendocrine neoplasms (pNENs).

METHODS

Two thousand six hundred sixty six pNENs were extracted from the Surveillance, Epidemiology, and End Results database to explore the metastatic patterns of pNENs. Metastatic patterns were categorized as single, two, or multiple (three or more) distant organ metastasis. The mean overall survival and hazard rate of different metastatic patterns were calculated by Kaplan-Meier and Cox proportional hazards models, respectively. The discriminatory capability of the modified M-stage classification was evaluated by Harrell's concordance index.

RESULTS

The overall survival time significantly decreased with an increasing number of metastatic organs. In addition, pNENs with only liver metastasis had better prognosis when compared to other metastatic patterns. Thus, we modified the M-stage classification (mM-stage) as follows: mM₀-stage, tumor without metastasis; mM₁-stage, tumor only metastasized to liver; mM₂-stage, tumor metastasized to other single distant organ (lung, bone, or brain) or two distant organs; mM₃-stage, tumor metastasized to three or more distant organs. Harrell's concordance index showed that the modified M-stage classification had superior discriminatory capability than both the American Joint Committee on Cancer (AJCC) and the European Neuroendocrine Tumor Society (ENETS) M-stage classifications.

CONCLUSIONS

The modified M-stage classification is superior to both AJCC and ENETS M-stage classifications in the prognosis of pNENs. In the future, individualized treatment and follow-up programs should be explored for patients with distinct metastatic patterns.

Gastrinomas: Medical or Surgical Treatment

This article reviews the role of surgical and medical management in patients with Zollinger-Ellison syndrome (ZES) due to a gastrin-secreting neuroendocrine tumor (gastrinoma). It concentrates on the status at present but also briefly reviews the changes over time in treatment approaches. Generally, surgical and medical therapy are complementary today; however, in some cases, such as patients with ZES and multiple endocrine neoplasia type 1, the treatment approach remains controversial.

Current Management of Pancreatic Neuroendocrine Tumors: From Demolitive Surgery to Observation

Incidental diagnosis of pancreatic neuroendocrine tumors (PanNETs) greatly increased in the last years. In particular, more frequent diagnosis of small PanNETs leads to many challenging clinical decisions. These tumors are mostly indolent, although a percentage (up to 39%) may reveal an aggressive behaviour despite the small size. Therefore, there is still no unanimity about the best management of tumor smaller than 2 cm. The risks of under/overtreatment should be carefully evaluated with the patient and balanced with the potential morbidities related to surgery. The importance of the Ki-67 index as a prognostic factor is still debated as well. Whenever technically feasible, parenchyma-sparing surgeries lead to the best chance of organ preservation. Lymphadenectomy seems to be another important prognostic issue and, according to recent findings, should be performed in noninsulinoma patients. In the case of enucleation of the lesion, a lymph nodal sampling should always be considered. The relatively recent introduction of minimally invasive techniques (robotic) is a valuable option to deal with these tumors. The current management of PanNETs is analysed throughout the many available published guidelines and evidences with the aim of helping clinicians in the difficult decision-making process.