ICD-10 Code D49.8 – Neoplasm of unspecified behavior of other specified sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D49.8 – Neoplasm of unspecified behavior of other specified sites
What it is
D49.8 identifies a neoplasm with unspecified behavior located in other specified sites. Use it when the site is documented, but the pathology or clinical behavior is not clearly stated as benign, malignant, or uncertain.
Clinical signs
Clinical features vary; refer to documentation. You may see a mass, lesion, or abnormal tissue finding, but the chart must support the site and the unspecified behavior.
When to use this code
Use this code when the provider documents a neoplasm in a specific “other specified” site and does not clarify its behavior. It may fit when imaging, exam, or pathology notes describe a growth but stop short of a definitive behavior. Check documentation if the record later identifies a more specific diagnosis.
Do not use for
Do not use this code if the lesion is documented as benign, malignant, or in situ. Also avoid it when the site is not specified or when another, more exact neoplasm code is available.
Coding tip
Verify both the anatomic site and the word “unspecified” in the record before assigning D49.8.