ICD-10 Code C44.99 – Other specified malignant neoplasm of skin, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C44.99 – Other specified malignant neoplasm of skin, unspecified
What it is
This code identifies a malignant skin tumor that is specified as “other” but not named more precisely in the record. Use it when the documentation confirms skin cancer, yet the exact site or subtype is not otherwise classified.
Clinical signs
Clinical features vary; refer to documentation. Skin cancers may appear as a changing lesion, nonhealing sore, or abnormal growth, but you should code only what is documented, not what is suspected clinically.
When to use this code
Use C44.99 when the provider documents a malignant neoplasm of skin and does not identify a more specific ICD-10-CM skin cancer code. It is appropriate when the record supports malignancy but leaves the site or exact type unspecified. If the pathology or note gives a more precise diagnosis, select that code instead.
Do not use for
Do not use this code for benign skin lesions, carcinoma in situ, or uncertain behavior neoplasms. If the documentation identifies a specific skin site or a different malignant histology, check documentation and code the more exact option.
Coding tip
Match the code to the most specific documented skin cancer diagnosis, and query for clarification when the note says “skin cancer” without enough detail.