Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2024 Mar 21:16:20363613241242383.
doi: 10.1177/20363613241242383. eCollection 2024.

Retroperitoneal mixed neuroendocrine non-neuroendocrine neoplasm: A case report and review of literature

John Adi Ashindoitiang  1 , Victor Ikechukwu Canice Nwagbara  1 , Theophilus Ugbem Ipeh  2 , Ben Chukwu  3 , Henry Olaleye Obanife  1 , Alfred Ottoh Eyong  3 , Maurice Efana Asuquo  1
Affiliations
Case Reports

Retroperitoneal mixed neuroendocrine non-neuroendocrine neoplasm: A case report and review of literature

John Adi Ashindoitiang et al. Rare Tumors. .

Abstract

The existence of both neuroendocrine and non-neuroendocrine histology in variable proportion in a lesion has been described by the World Health Organisation (WHO) as mixed neuroendocrine and non-neuroendocrine neoplasm (MiNEN). The pathogenesis of this tumour remains controversial but molecular studies point towards a common monoclonal origin. Tumours are classified as functioning and nonfunctioning based on substances secreted. The nonfunctioning tumours may be discovered due to its local effect. Presented is a 66-year-old male with an intra-abdominal mass, underwent laparotomy and excision biopsy with transient right lower limb lymphoedema. Histology confirmed retroperitoneal MiNEN with no evidence of tumour recurrence 12 months following surgery. MiNENs should be considered as a differential diagnosis in patients with intra-abdominal mass. Surgical resection is recommended as this may offer the best treatment option.

Keywords: WHO classifications; mixed adenoneuroendocrine carcinoma; mixed neuroendocrine non-neuroendocrine neoplasm; retroperitoneum.

PubMed Disclaimer

Conflict of interest statement

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
USS showing an intra abdominal mass.
Figure 2.
Figure 2.
CT scan showing hypodense multi-lobulated mass anterior to the right psoas muscle.
Figure 3.
Figure 3.
Intraabdominal tumour in situ.
Figure 4.
Figure 4.
(a) Mixed neuroendocrine (b) non-neuroendocrine neoplasm, H & E × 40 (c) mixed neuroendocrine(arrow heads), non-neuroendocrine(arrows), H & E × 100.
Figure 5.
Figure 5.
(a) Mixed neuroendocrine, (b) non-neuroendocrine neoplasm, H & E × 100.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Frizziero M, Chakrabarty B, Nagy B, et al. Mixed neuroendocrine non-neuroendocrine neoplasms: a systematic review of a controversial and underestimated diagnosis. J Clin Med 2020; 9(273): 1–23. - PMC - PubMed
    1. Johnson PR. Gastroenteropancreatic neuroendocrine (carcinoid) tumors in children. Semin Pediatr Surg 2014; 23: 91–95. - PubMed
    1. Bosman FT, Carneiro F, Hruban RH, et al. WHO classification of tumours of the digestive system. 4th ed. Lyon France: International Agency for Research on Cancer(IARC), 2010.
    1. Lloyd RV, Osamma RY, Kloppel G, et al. WHO Classification of Tumours of endocrine organs. 4th ed. Lyon France: International Agency on Research for Cancer(IARC), 2017.
    1. La Rosa S, Sessa F, Uccella S. Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs): unifying the concept of a heterogeneous group of neoplasms. Endocr Pathol 2016; 27: 284–311. - PubMed

Publication types

LinkOut - more resources