ICD-10 Code D03.122 – Melanoma in situ of left lower eyelid, including canthus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D03.122 – Melanoma in situ of left lower eyelid, including canthus
What it is
D03.122 identifies melanoma in situ confined to the left lower eyelid, including the canthus. “In situ” means the abnormal melanocytic cells remain within the epidermis and have not invaded deeper tissue.
Clinical signs
Clinical features vary; refer to documentation. You may see a pigmented or irregular eyelid lesion with asymmetry, border irregularity, color variation, or change over time, and pathology should confirm melanoma in situ.
When to use this code
Use this code when documentation states melanoma in situ of the left lower eyelid, including the medial or lateral canthus. It fits confirmed noninvasive disease limited to that exact site. Check documentation if laterality, eyelid level, or canthus involvement is unclear.
Do not use for
Do not use D03.122 for invasive melanoma, uncertain behavior, or lesions on the upper eyelid or other eyelids. Also avoid it when the record does not specify the left lower eyelid or canthus.
Coding tip
Verify both laterality and eyelid location in the pathology or operative note before assigning D03.122.