ICD-10 Code C44.121 – Squamous cell carcinoma of skin of unspecified eyelid, including canthus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C44.121 – Squamous cell carcinoma of skin of unspecified eyelid, including canthus
What it is
This code identifies squamous cell carcinoma arising in the skin of an eyelid, including the canthus, when the exact eyelid side or location is not specified. It represents a malignant skin tumor that needs precise site documentation.
Clinical signs
Typical findings include a persistent scaly, crusted, or ulcerated eyelid lesion that does not heal. Clinical features vary; refer to documentation, especially if the lesion is described as suspicious, biopsy-proven, or locally destructive.
When to use this code
Use this code when the record confirms squamous cell carcinoma of the eyelid skin, but does not specify upper, lower, right, left, or canthus side details. It also fits when the provider documents the lesion as on an unspecified eyelid or canthal skin site. If the note gives a more exact eyelid location, code that instead.
Do not use for
Do not use this code for non-melanoma skin lesions that are benign, premalignant, or not confirmed as squamous cell carcinoma. Check documentation if the site is the conjunctiva, another facial skin area, or a different eyelid subsite.
Coding tip
Verify both the histology and the anatomic site; unspecified laterality or eyelid detail belongs here only when the documentation is incomplete.