ICD-10 Code D09.8 – Carcinoma in situ of other specified sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D09.8 – Carcinoma in situ of other specified sites
What it is
D09.8 identifies carcinoma in situ at a site that is specified in the record but not named by a more specific ICD-10 code. It means abnormal cells are confined to the epithelium and have not invaded surrounding tissue.
Clinical signs
Clinical features vary; refer to documentation. Diagnosis is usually based on pathology showing malignant-appearing cells limited to the original tissue layer, without evidence of invasion.
When to use this code
Use D09.8 when the provider documents carcinoma in situ and identifies an anatomic site that does not have its own more specific code. It is appropriate when the lesion is noninvasive and the record supports a site-specific in situ diagnosis. Check documentation if the site is unclear or if invasive cancer is suspected.
Do not use for
Do not use this code for invasive malignant neoplasms, dysplasia without carcinoma in situ, or unspecified in situ neoplasms that have a more specific code. If the site is not documented, check documentation.
Coding tip
Match the exact site and confirm that the pathology or provider note supports in situ disease before assigning D09.8.