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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.

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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

References

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