ICD-10 Code C43.31 – Malignant Melanoma of Nose (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C43.31 – Malignant melanoma of nose
What it is
C43.31 identifies a malignant melanoma located on the nose. Use it when documentation specifies a primary melanoma of the nasal skin or external nose.
Clinical signs
Clinical features vary; refer to documentation. Melanoma is typically described as a suspicious pigmented or changing skin lesion, and diagnosis is confirmed by pathology.
When to use this code
Use this code when the provider documents malignant melanoma of the nose, including a biopsy-proven primary lesion on nasal skin. It is appropriate when the site is clearly the nose and not another facial area. Check documentation if the record only says facial melanoma.
Do not use for
Do not use this code for benign nevi, dysplastic nevi, or non-melanoma skin cancers. If the lesion is on a different part of the face or the site is unclear, check documentation.
Coding tip
Verify both malignancy and exact anatomic site before assigning C43.31.