Carcinoma in situ of other and unspecified parts of intestine

This code signifies the presence of carcinoma in situ, a non-invasive form of cancer where abnormal cells are confined to the epithelial layer, within various parts of the intestine other than the colon, rectum, or anus. It indicates that the malignant cells have not spread beyond the original tissue layer.

Assign this code when documentation specifies carcinoma in situ affecting parts of the intestine such as the duodenum, jejunum, ileum, or unspecified intestinal segments. This diagnosis is typically made following biopsy and histopathological examination confirming non-invasive neoplastic cells.

• Differentiate from invasive carcinoma of the intestine, which would be coded to a malignant neoplasm category.
• Ensure the documentation clearly states "in situ" and specifies an intestinal site other than the colon, rectum, or anus.
• If the specific intestinal site is known (e.g., duodenum), consider if a more precise code within the 230 series is available.