Published online Feb 21, 2021. doi: 10.3748/wjg.v27.i7.624
Peer-review started: November 15, 2020
First decision: December 17, 2020
Revised: December 24, 2020
Accepted: January 13, 2021
Article in press: January 13, 2021
Published online: February 21, 2021
Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) are a rare tumor type. However, their prevalence might be largely underestimated due to diagnostic limitations and insufficient scientific understanding. The clinical manifestations, treatment, and prognosis of this type of tumor are still poorly understood. Our research on the risk factors, clinical manifestations, and prognosis related to this rare tumor type is of great significance for optimizing clinical treatment.
MiNEN associated risk factors, clinical manifestations, and prognosis must be explored to improve our understanding of this rare tumor type and optimize clinical treatment.
We have identified the risk factors that influence the prognosis of patients with gastroenteropancreatic MiNEN (GEP-MiNEN). We also compared prognostic differences between GEP-MiNEN and gastroenteropancreatic neuroendocrine tumors, neuroendocrine carcinomas (NEC), and poorly differentiated adenocarcinoma to improve the understanding of GEP-MiNEN and to guide future clinical treatment.
This is a single-center, retrospective study. We retrospectively analyzed the clinical data of patients who were diagnosed with GEP-MiNEN. Risk factors influencing patient prognosis were assessed using Kaplan-Meier curves and Cox regression models. We compared the results with randomly selected patients with gastro-enteropancreatic neuroendocrine tumors, NEC, and poorly differentiated adeno-carcinomas.
Most GEP-MiNEN in our study were gastric tumors, a few were intestinal tumors, and a minority, pancreatic tumors. The median overall survival was 30 mo. Ki- 67 index ≥ 50%, high proportion of NEC, lymph node involvement, distant metastasis, and higher clinical stage were independent risk factors affecting the prognosis of patients with GEP-MiNEN. The median overall survival was shorter for patients with NEC than for those with MiNEN but did not significantly differ from those with poorly differentiated adenocarcinoma and MiNEN. Thus, patients with GEP-MiNEN and those with adenocarcinoma should be similarly treated. Furthermore, the treatment of any suspected or diagnosed GEP-MiNEN patient should be discussed at a multidisciplinary expert meeting to determine optimal personalized treatment. However, the number of patients in the present retrospective study was limited by the rarity of GEP-MiNEN, and they were sourced from a single institution. Therefore, further multicenter, larger-cohort studies are warranted to clarify the clinicopathological features and biological behavior of GEP-MiNEN.
A poor prognosis is associated with GEP-MiNEN. Ki-67 index, tumor composition, lymph node involvement, distant metastasis, and clinical stage are important factors for patient prognosis.
In view of the limited number of patients and the short-term follow-up of our study, a larger prospective study with long-term follow-up is needed to confirm our results.