ICD-10 · PDGM grouping
C66 Malignant neoplasm of ureter
All 3 codes in the C66 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
3
Can lead a claim
2
Cannot lead a claim
1
What CMS assigns to C66
2 of the 3 codes group to MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases; 1 is assigned no clinical group. 2 of the 3 count toward the Malignant Neoplasm of Urinary Tract comorbidity subgroup; 1 is assigned none. 2 of the 3 can lead a claim.
- Malignant Neoplasm of Urinary Tract
Every code in C66
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| C66.1 | Malignant neoplasm of right ureter | Can lead a claim | K | Malignant Neoplasm of Urinary Tract |
| C66.2 | Malignant neoplasm of left ureter | Can lead a claim | K | Malignant Neoplasm of Urinary Tract |
| C66.9 | Malignant neoplasm of unspecified ureter | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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