Carcinoma in situ of other parts of respiratory system

This code signifies the presence of non-invasive malignant cells confined to the epithelial layer of various respiratory system sites, excluding the larynx, trachea, bronchus, and lung. It represents an early stage of cancer where the abnormal cells have not spread beyond their original location.

Assign this code when documentation specifies carcinoma in situ of respiratory sites such as the nasopharynx, oropharynx, hypopharynx, or paranasal sinuses. This diagnosis is typically confirmed by biopsy showing intraepithelial neoplasia without invasion.

• Carefully review documentation to ensure the carcinoma in situ is explicitly stated for a respiratory site other than larynx, trachea, bronchus, or lung.
• Distinguish from invasive carcinomas of the respiratory system (C30-C39) and benign neoplasms (D14.-).
• Pay close attention to the "Excludes1" notes to avoid incorrect co-coding with carcinoma in situ of the ear or nose (NOS or skin).