Neoplasm of uncertain behavior of unspecified renal pelvis

This code signifies a tumor originating in the renal pelvis whose biological behavior (benign or malignant) cannot be definitively determined from pathological examination. It represents an ambiguous neoplastic process within the kidney's collecting system, awaiting further diagnostic clarity.

Use this code when pathology reports indicate a renal pelvis neoplasm with features that are neither clearly benign nor clearly malignant, often described as "borderline" or "of uncertain malignant potential." Documentation must explicitly state the uncertain behavior and the renal pelvis as the primary site.

• Do not use this code if the pathology definitively states benign (e.g., papilloma) or malignant (e.g., carcinoma) behavior; use the appropriate benign or malignant neoplasm code instead.
• Ensure the documentation specifies "renal pelvis" and not just "kidney" to support this site-specific code.
• Consider sequencing this code as the primary diagnosis when the uncertain neoplasm is the reason for the encounter, followed by codes for any associated symptoms or conditions.