Malignant neoplasm of unspecified renal pelvis

This diagnosis code signifies a cancerous tumor originating in the renal pelvis, the funnel-shaped structure in the kidney that collects urine before it passes to the ureter. The "unspecified" nature indicates that the specific part of the renal pelvis affected is not documented.

This code is appropriate when documentation confirms a primary malignant neoplasm of the renal pelvis, but the laterality (left, right, or bilateral) or more specific anatomical site within the renal pelvis is not specified. It is used when the physician's diagnosis explicitly states "malignant neoplasm of renal pelvis, unspecified."

• Avoid using this code if laterality (left or right) is documented; instead, use the more specific codes (C65.1 or C65.2).
• Ensure the documentation clearly states "malignant" to differentiate from benign or uncertain neoplasms.
• Sequence this code as the primary diagnosis when the renal pelvis malignancy is the reason for the encounter, followed by any relevant secondary diagnoses.