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Apple core sign (colon)

Last revised by Dr MT. Niknejad on 26 Jun 2022

The apple core sign, also known as the napkin ring sign (bowel), is most frequently associated with constriction of the lumen of the colon by a stenosing annular colorectal carcinoma.

Differential diagnosis

The appearance of the apple-core lesion of the colon also can be caused by other diseases 3:

See also

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Cases and figures

  • Figure 1: apple core
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  • Figure 2: apple-core lesion
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  • Figure 2: apple-core lesion
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  • Figure 3: gross pathology - colorectal cancer
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  • Case 1
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  • Case 2
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  • Case 3
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  • Case 4
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  • Case 5
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  • Case 6
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  • Case 7
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