ICD-10 Code D48 – Neoplasm of uncertain behavior of other and unspecified sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D48 – Neoplasm of uncertain behavior of other and unspecified sites
What it is
D48 identifies a neoplasm whose behavior cannot be clearly classified as benign or malignant, and the site is other or not otherwise specified. Use it when the record documents uncertain behavior but does not name a more specific code.
Clinical signs
Clinical features vary; refer to documentation. Commonly, the lesion is described as atypical, indeterminate, or requiring further evaluation because pathology has not confirmed benign or malignant behavior.
When to use this code
Use D48 when the provider documents a neoplasm of uncertain behavior and the anatomic site is not captured by a more specific ICD-10 code. It may apply to masses or lesions awaiting definitive classification. Code only from documented findings; check documentation if the site or behavior is unclear.
Do not use for
Do not use D48 for clearly benign or malignant neoplasms, or when the record gives a more specific uncertain-behavior code. If the diagnosis is only “mass” or “lesion” without uncertain behavior, check documentation.
Coding tip
Verify both the behavior and the site in the pathology or provider note before assigning D48.