Carcinoma in situ of trachea

This code signifies the presence of abnormal, non-invasive epithelial cells confined to the mucosal lining of the trachea, exhibiting characteristics of malignancy but without invasion through the basement membrane. It represents a pre-invasive form of cancer, often considered a precursor to invasive squamous cell carcinoma.

Apply this code when pathology reports confirm carcinoma in situ specifically within the tracheal tissue. Documentation should clearly state "carcinoma in situ" or "intraepithelial neoplasia, high grade" of the trachea, without evidence of stromal invasion.

• Differentiate from invasive tracheal carcinoma; this code is strictly for non-invasive disease.
• Ensure the pathology report explicitly states the site as the trachea.
• Do not use for dysplasia or atypical hyperplasia without a definitive diagnosis of carcinoma in situ.