ICD-10 Code C44.21 – Basal cell carcinoma of skin of ear and external auricular canal (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C44.21 – Basal cell carcinoma of skin of ear and external auricular canal
What it is
C44.21 identifies basal cell carcinoma arising on the skin of the ear or external auricular canal. It is a malignant skin tumor that usually grows slowly and is often locally destructive.
Clinical signs
Typical findings include a pearly or translucent papule, ulceration, crusting, or a nonhealing lesion on the ear. Clinical features vary; refer to documentation.
When to use this code
Use C44.21 when the provider documents basal cell carcinoma specifically involving the ear or external auricular canal. Confirm that the site is skin of the ear, not another head or neck location. If the record only says “basal cell carcinoma” without site detail, check documentation before coding.
Do not use for
Do not use this code for basal cell carcinoma of other skin sites or for non-basal skin cancers. If the lesion is documented as benign, premalignant, or unspecified, this code is not appropriate.
Coding tip
Code the exact anatomic site documented; laterality is not part of this code, so site specificity matters most.