Satisfactory anal smear but lacking transformation zone

This code indicates a normal anal Pap smear result, but the sample did not contain cells from the transformation zone. The transformation zone is the area where squamous epithelium meets columnar epithelium, and it is the most common site for anal dysplasia and cancer development. Its absence means the sample may not be fully representative for detecting precancerous changes.

Use this code when an anal Pap smear report indicates "satisfactory for evaluation" but explicitly states "lacking transformation zone components." This typically occurs in screening or follow-up for patients at risk for anal squamous intraepithelial lesions (ASIL). Documentation must clearly state both the satisfactory nature of the smear and the absence of the transformation zone.

• Do not use this code if the smear is unsatisfactory for other reasons (e.g., insufficient cellularity, obscuring inflammation).
• This code represents a finding, not a definitive diagnosis of disease; further investigation may be warranted.
• Sequence this code as a secondary diagnosis if a definitive anal pathology (e.g., ASIL) is identified from a different specimen or subsequent biopsy.