ICD-10 Code C44.90 – Unspecified malignant neoplasm of skin, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C44.90 – Unspecified malignant neoplasm of skin, unspecified
What it is
C44.90 identifies a malignant skin tumor when the site is not further specified. Use it when documentation confirms skin cancer, but the record does not name the exact skin location.
Clinical signs
Clinical features vary; refer to documentation. Skin cancers may present as a new or changing lesion, nonhealing sore, bleeding area, or abnormal growth, but the precise appearance depends on the tumor type.
When to use this code
Use this code when the provider documents a malignant neoplasm of skin and the affected site is unspecified. It is appropriate when the chart lacks a more exact anatomic location or laterality. Code the most specific skin cancer diagnosis available if documented.
Do not use for
Do not use C44.90 if the record identifies a specific skin site or a different malignant skin diagnosis. Do not use it for benign lesions, dysplastic nevi, or lesions that are only suspicious; check documentation.
Coding tip
Query the provider for the exact lesion site before defaulting to an unspecified code.