Gastroenteropancreatic neuroendocrine tumor registry study in China

Comprehensive analysis of mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs): A SEER database analysis of 767 cases

Background

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is an extremely rare entity, consisting of neuroendocrine and non-neuroendocrine components. It can occur in various organs throughout the body, with a rising incidence. Its clinical management is a rapidly growing field of interest; however, large-scale patient cohorts are still missing to guide clinical practice.

Patients and methods

The demographic, clinicopathological, and survival information of all patients diagnosed with MiNEN in the national Surveillance, Epidemiology, and End Results (SEER) program database (2000-2017) were extracted and further analyzed. The information of the patients before and after 2010 was compared to understand the epidemiological changes of MiNEN. The characteristics of MiNEN originating in different organs were compared. The clinical significance of surgical resection for metastatic MiNENs was also analyzed.

Results

A total of 1081 patients were screened, and after applying the exclusion criteria, 767 patients were finally analyzed. There was no obvious sex preference (49.2% vs 50.8%, p>0.05) and the majority of the patients were Caucasians (n=627, 81.7%). A total of 88.3% of the patients were older than 50 years old, and the median age was 60 years. 79.3% of the tumors are located in the distal digestive tract, and 67.7% were grade 3/4. Distant metastasis was presented in 33.9% of the patients at diagnosis. A total of 88% of the patients underwent surgical treatments. The number of patients increased 10-fold between 2000 and 2017. There was no significant difference in sex, race, stage, or surgical treatments among the patients diagnosed before and after 2010. More patients older than 60 years were diagnosed after 2010 (p=0.009). The median survival was 61.0 ± 9.8 months for the whole cohort. After multivariate analysis, older age (>60 years, p<0.01), more advanced stage (p<0.01), grade 3/4 (p<0.01), and non-surgical treatment (p<0.01) were independent risk factors for poorer survival. The appendiceal MiNENs showed the best prognosis. A total of 260 metastatic MiNENs were further analyzed. Only patients with metastatic MiNENs originating from the appendix had a potential benefit from surgical resection, compared to other sites (p=0.05).

Conclusion

This study provides the epidemiological, clinicopathological, and survival information of the largest number of MiNEN patients. Although MiNEN is an extremely rare malignant neoplasm, its incidence increases rapidly. The majority of the patients suffered from advanced-stage disease, which highlights the need for improvement of early detection in the future. The appendix is the most common primary site of MiNEN, and surgical resection for selected metastatic MiNEN originating in the appendix has favorable survival outcomes.

Clinicopathologic Characteristics of Gastroenteropancreatic Neuroendocrine Tumors: Experience of a National Referral Hospital in Indonesia

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have variable biological behavior although they are all malignant. This study presents the 10-year prevalence along with the clinicopathologic characteristics of GEP-NETs and their association with tumor grade at a national referral hospital in Indonesia. This is a retrospective cross-sectional study of patients with GEP-NET confirmed by histomorphology and immunohistochemistry who presented to Cipto Mangunkusumo Hospital from 2009 to 2019. Clinical characteristics included age, sex, primary site, tumor stage, metastasis, hormone status, and chief complaints. Pathological characteristics included the type of GEP-NET, specimen type, grade, and presence of lymphovascular invasion (LVI). Statistical analysis was performed to determine the association between characteristics and tumor grade. A total of 84 cases of GEP-NET from 2009 to 2019 were included; of these, 38.1% were neuroendocrine tumors (NETs), 28.6% were neuroendocrine carcinomas (NECs), and 33.3% were mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN). The mean patient age was 48.36 years, and the male to female ratio was 1. GEP-NETs predominantly originated from the rectum (21.4%) and were mostly non-functioning (90.5%) with an average tumor size of 4.77 cm. Most tumors were localized (53.6%), but metastasis was found in 28.6% cases. LVI was positive in 35.7% cases. High-grade tumors were more common (54.3%) than low-grade tumors. High-grade tumors were associated with unknown primary sites, dissemination, LVI, and larger tumor size. To conclude, GEP-NETs can arise from any site in the gastrointestinal tract and have variable clinicopathologic characteristics. Primary site, stage, LVI, and tumor size are associated with grade.

Application of multiomics sequencing and advances in the molecular mechanisms of pancreatic neuroendocrine neoplasms

The incidence of pancreatic neuroendocrine neoplasms (PanNENs) has gradually increased. PanNENs comprise two subtypes with different clinical manifestations and molecular mechanisms: functional PanNENs and nonfunctional PanNENs. Excessive hormones and tumor progression severely affect the quality of life of patients or are even life threatening. However, the molecular mechanisms of hormone secretion and tumor progression in PanNENs have not yet been fully elucidated. At present, advancements in sequencing technologies have led to the exploration of new biological markers and an advanced understanding of molecular mechanisms in PanNENs. Multiomics sequencing could reveal differences and similarities in molecular features in different fields. However, sequencing studies of PanNENs are booming and should be summarized to integrate the current findings. In this review, we summarize the current status of multiomics sequencing in PanNENs to further guide its application. We explore mainly advancements in the genome, transcriptome, and DNA methylation fields. In addition, the cell origin of PanNENs, which has been a hot issue in sequencing research, is described in multiple fields.