Non-Billable / Non-Specific Code
ICD-10-CM C66 is the diagnosis code for Malignant neoplasm of ureter. This code falls under the section "Malignant neoplasms of urinary tract" within Chapter 2 — Neoplasms (C00-D49). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
The following conditions should never be coded at the same time as C66. They are mutually exclusive:
Understanding where C66 sits in the ICD-10-CM classification helps ensure proper coding:
No, C66 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.
C66 is the ICD-10-CM diagnosis code for "Malignant neoplasm of ureter". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
C66 is located in Section C64-C68 — "Malignant neoplasms of urinary tract" within Chapter 2 of the ICD-10-CM Tabular List.
C66 has 3 sub-code(s) that provide more specific detail: C66.1, C66.2, C66.9.
Use C66 when the patients documented diagnosis matches "Malignant neoplasm of ureter" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Malignant neoplasm of ureter is C66.
No, C66 is non-billable. Use a more specific sub-code for primary diagnosis billing.
C66 is in Chapter 2 of the ICD-10-CM Tabular List.
Type 1 Excludes for C66 include: malignant neoplasm of ureteric orifice of bladder (C67.6).
Yes, C66 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.