ICD-10 Code D49.59 – Neoplasm of unspecified behavior of other genitourinary organ (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D49.59 – Neoplasm of unspecified behavior of other genitourinary organ
What it is
D49.59 identifies a tumor in another genitourinary organ when the behavior is not clearly documented as benign, malignant, or uncertain. Use it only when the record specifies a genitourinary site but does not name a more exact code.
Clinical signs
Clinical features vary; refer to documentation. You may see a mass, abnormal imaging finding, or organ-specific symptoms, but the key point is that the provider has not defined the lesion’s behavior.
When to use this code
Use this code when the note names an unspecified-behavior neoplasm in an “other” genitourinary organ and no more specific code is available. It may apply after imaging, pathology, or specialist assessment when the chart still lacks a definitive behavior statement. Check documentation if the organ is not clearly identified.
Do not use for
Do not use D49.59 for clearly benign, malignant, or in situ tumors, because those require different codes. Also avoid it when the documented site has a more specific neoplasm code.
Coding tip
Confirm both the organ and the word “unspecified behavior” in the record before assigning D49.59.