Carcinoma in situ of larynx

This code signifies the presence of non-invasive malignant cells confined to the epithelial layer of the larynx, without evidence of invasion into deeper tissues. It represents an early stage of cancer development within the voice box.

Apply this code when pathology reports confirm carcinoma in situ specifically within the laryngeal structures. Documentation should clearly state "carcinoma in situ of larynx" or similar, excluding other laryngeal subsites specified in the Excludes1 note.

• Carefully review pathology reports to ensure the carcinoma in situ is explicitly located within the larynx and not other excluded laryngeal areas.
• Do not use this code if the documentation indicates any invasion beyond the epithelial layer; in such cases, a malignant neoplasm code would be appropriate.
• Be mindful of the Excludes1 notes to avoid miscoding with carcinoma in situ of the aryepiglottic fold, interarytenoid fold NOS, hypopharyngeal aspect, or marginal zone.