ICD-10 Code C66.2 – Malignant neoplasm of left ureter (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C66.2 – Malignant neoplasm of left ureter
What it is
This code identifies a malignant tumor arising in the left ureter, the tube that carries urine from the kidney to the bladder. It is used when documentation specifies the left side.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include hematuria, flank pain, or obstructive urinary symptoms, but the diagnosis should be supported by imaging, endoscopy, or pathology when available.
When to use this code
Use C66.2 when the record clearly states primary cancer of the left ureter. It also fits encounters for confirmed malignancy under evaluation, staging, or follow-up, if the left ureter site remains documented. Check documentation if laterality is unclear.
Do not use for
Do not use this code for benign ureteral lesions, unspecified ureteral cancer, or tumors documented in the right ureter or renal pelvis. If the site is not stated, choose the unspecified code instead.
Coding tip
Verify laterality in the pathology, operative note, or imaging report before assigning C66.2.