apple core

apple core appearance

IMAGING, PATHOLOGY 

A descriptive term referring to a pattern of luminal constriction caused by mucosal erosion and stenosis with “shouldering” of the margins, that corresponds to an exophytic encircling and constricting mass in the large intestine lumen, which has been fancifully likened to, depending on one’s perspective, an apple core or a napkin ring 

Aetiology Large adenocarcinoma, especially in the left colon, which may obstruct the faecal flow, resulting in

apple core appearance colon with encircling tumour arising in mucosa and constricting the lumen

pencil-thin stools. The lesion may be partially mimicked by concentric amebomas in Entamoeba histolytica granulomas, by exuberant submucosal fibrosis in Crohn’s disease, by stenosing fibrotic stages of diverticulosis coli, and may occur in small intestinal adenocarcinoma.

Apple core is generally preferred by radiologists; napkin ring is preferred by pathologists and surgeons. 

Synonyms Apple core lesion, napkin ring lesion