C95 vs T66.XXXD
C95 (Leukemia of unspecified cell type) compared with T66.XXXD (Radiation sickness, unspecified, subsequent encounter), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. T66.XXXD carries an Excludes1 note covering C95: “leukemia (C91-C95)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| C95Leukemia of unspecified cell type | T66.XXXDRadiation sickness, unspecified, subsequent encounter | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | C00-D49 — Neoplasms (C00-D49) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Leukemia of unspecified cell type is a non-billable ICD-10-CM category code (C95). | Radiation sickness, unspecified, subsequent encounter is a billable ICD-10-CM diagnosis code (T66D). |
| 7th character | — | The appropriate 7th character is to be added to code T66 |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources