ICD-10 Code D01.4 – Carcinoma in situ of other and unspecified parts of intestine (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D01.4 – Carcinoma in situ of other and unspecified parts of intestine
What it is
This code identifies a preinvasive malignant epithelial lesion in the intestine outside the more specific sites named elsewhere. The abnormal cells remain in place and have not invaded deeper tissue.
Clinical signs
Clinical features vary; refer to documentation. Diagnosis is usually based on pathology showing carcinoma in situ, with the involved intestinal site described as other or unspecified.
When to use this code
Use this code when the provider documents carcinoma in situ of the intestine and does not specify a more exact intestinal location. It also fits pathology or operative reports that confirm in situ disease in an intestinal segment not otherwise classified. Check documentation if the site is unclear.
Do not use for
Do not use this code for invasive intestinal cancer or for lesions described as adenoma, dysplasia, or benign polyps. If the documentation names a specific intestinal site with a more precise ICD-10 option, code that instead.
Coding tip
Match the code to the exact anatomic wording in the pathology or provider note, and query for the site if “unspecified” is not supported.