ICD-10 Code D01.40 – Carcinoma in situ of unspecified part of intestine (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D01.40 – Carcinoma in situ of unspecified part of intestine
What it is
D01.40 identifies carcinoma in situ affecting an unspecified part of the intestine. It means abnormal cells are present in the lining, but there is no documented invasion into deeper tissue.
Clinical signs
Clinical features vary; refer to documentation. Diagnosis is usually based on pathology or endoscopic findings showing in situ malignancy without evidence of invasive cancer.
When to use this code
Use this code when the record states carcinoma in situ of the intestine but does not specify the exact intestinal site. It is appropriate for confirmed in situ disease documented by pathology, operative report, or specialist note. If the site is specified elsewhere, code that more precise diagnosis instead.
Do not use for
Do not use it for invasive intestinal cancer, benign polyps, or dysplasia without a carcinoma in situ diagnosis. Check documentation if the pathology report does not clearly confirm in situ disease.
Coding tip
If the note names the bowel segment, code the specified site rather than this unspecified code.