ICD-10 Code D00.03 – Carcinoma in situ of gingiva and edentulous alveolar ridge (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D00.03 – Carcinoma in situ of gingiva and edentulous alveolar ridge
What it is
This code identifies carcinoma in situ confined to the gingiva or edentulous alveolar ridge. The abnormal cells are present in the surface lining but have not invaded deeper tissue.
Clinical signs
Findings may include a persistent oral mucosal lesion, such as a white, red, or mixed patch, ulcer, or thickened area. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents carcinoma in situ specifically involving the gingiva or an edentulous alveolar ridge. It applies when the lesion is noninvasive and the site is clearly identified. Check documentation if the note only says oral dysplasia or suspicious lesion.
Do not use for
Do not use this code for invasive oral cancer, unspecified oral site lesions, or benign gingival disease. If the record does not confirm carcinoma in situ at this exact site, check documentation.
Coding tip
Confirm both the in situ diagnosis and the exact anatomic site before assigning D00.03.