ICD-10 Code D02.20 – Carcinoma in situ of unspecified bronchus and lung (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D02.20 – Carcinoma in situ of unspecified bronchus and lung
What it is
This code identifies carcinoma in situ in the bronchus or lung when the exact site is not specified. The abnormal cells are confined to the lining and have not invaded deeper tissue.
Clinical signs
Clinical features vary; refer to documentation. Diagnosis is usually based on pathology or biopsy showing malignant cells limited to the epithelium, with no evidence of invasion or metastatic spread.
When to use this code
Use D02.20 when the record documents carcinoma in situ of the bronchus or lung but does not identify a more specific site. It also fits when the provider states “unspecified” bronchus or lung involvement. Check documentation if laterality, lobe, or exact bronchial site is available.
Do not use for
Do not use this code for invasive lung cancer, benign pulmonary lesions, or metastatic disease. If the note specifies a more precise bronchial or lung site, code that documented site instead.
Coding tip
Verify that the pathology supports in situ disease and that the documentation truly lacks a more specific site.