"Not-So-Indolent" neuroendocrine neoplasms: two case reports of gastrointestinal small cell neuroendocrine carcinomas.

ABSTRACT:

Background

Small cell neuroendocrine carcinomas (SCNECs) of the gastrointestinal (GI) tract are exceedingly rare and aggressive malignancies. Unlike pulmonary SCNECs, which are well-characterized, extrapulmonary GI-SCNECs lack established diagnostic pathways and treatment algorithms due to their rarity and histopathological overlap with other poorly differentiated tumors. Literature on their clinical course remains limited to isolated reports, with scarce data on site-specific presentations. These two cases contribute to the existing literature by illustrating distinct primary GI sites (gastric and rectal), underscoring the challenges in early diagnosis and the aggressive clinical progression despite intervention.

Case description

The first patient, an 80-year-old man, prese

SUBMITTER: Dashti A 

PROVIDER: S-EPMC12593066 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature