Merkel cell carcinoma of right lower eyelid, inc canthus

This code identifies a rare and aggressive neuroendocrine carcinoma originating from Merkel cells, specifically located on the right lower eyelid, encompassing the canthal region. This malignancy is characterized by rapid growth and a high propensity for local recurrence and metastasis.

Apply this code when documentation explicitly states a diagnosis of Merkel cell carcinoma affecting the right lower eyelid, including any involvement of the inner or outer canthus. This diagnosis is typically confirmed by biopsy and histopathological examination.

• Ensure the documentation clearly specifies "Merkel cell carcinoma" and not another type of skin cancer.
• Verify the exact anatomical location is the "right lower eyelid, including canthus" to differentiate from other eyelid or facial sites.
• Consider additional codes for any associated metastatic disease or subsequent treatment encounters.