HCC 454: Stem Cell, Including Bone Marrow, Transplant Status/Complications ICD-10-CM
CMS-HCC Category 454 (Stem Cell, Including Bone Marrow, Transplant Status/Complications) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.416 and 1.596 to a beneficiary's RAF score depending on the payment segment (1.068 for a community, non-dual, aged enrollee). 14 ICD-10-CM diagnosis codes map to HCC 454. It sits at the top of its hierarchy: no other condition category supersedes it.
RAF Weight by Payment Segment 7 segments
| Payment Segment | Relative Factor |
|---|---|
| Community, non-dual, aged | 1.068 |
| Community, partial-benefit dual, aged | 1.338 |
| Community, full-benefit dual, aged | 1.326 |
| Community, non-dual, disabled | 0.452 |
| Community, partial-benefit dual, disabled | 0.416 |
| Community, full-benefit dual, disabled | 0.608 |
| Institutional | 1.596 |
A beneficiary is scored in exactly one segment, set by Medicaid (dual) status, aged or disabled entitlement, and residence. Factors are relative weights, not dollar amounts; new-enrollee segments score on demographics only. HCC 454 neither supersedes nor is superseded by any other category, so it always counts alongside unrelated HCCs.
ICD-10-CM Codes That Map to HCC 454 14 codes
- D89.810 Acute graft-versus-host disease from V24 HCC 47
- D89.811 Chronic graft-versus-host disease from V24 HCC 47
- D89.812 Acute on chronic graft-versus-host disease from V24 HCC 47
- D89.813 Graft-versus-host disease, unspecified from V24 HCC 47
- M31.11 Hematopoietic stem cell transplantation-associated thrombotic microangiopathy [HSCT-TMA] from V24 HCC 186
- T86.00 Unspecified complication of bone marrow transplant from V24 HCC 186
- T86.01 Bone marrow transplant rejection from V24 HCC 186
- T86.02 Bone marrow transplant failure from V24 HCC 186
- T86.03 Bone marrow transplant infection from V24 HCC 186
- T86.09 Other complications of bone marrow transplant from V24 HCC 186
- T86.5 Complications of stem cell transplant from V24 HCC 186
- Z48.290 Encounter for aftercare following bone marrow transplant from V24 HCC 186
- Z94.81 Bone marrow transplant status from V24 HCC 186
- Z94.84 Stem cells transplant status from V24 HCC 186
Every code above carries the full HCC 454 weight when documented and reported on a Medicare Advantage encounter. The code link opens its full page with the complete risk adjustment card.
Questions About HCC 454
What is HCC 454 in the CMS-HCC model?
HCC 454 is CMS-HCC Category 454 (Stem Cell, Including Bone Marrow, Transplant Status/Complications) in the V28 risk adjustment model. It covers 14 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 454?
For payment year 2026, HCC 454 adds 1.068 to the RAF score of a community, non-dual, aged beneficiary (living at home, age 65 or over, not also enrolled in Medicaid). The published weights range from 0.416 to 1.596 across the seven payment segments shown above.
Related References
Source: Centers for Medicare & Medicaid Services, Payment Year 2026 risk adjustment mapping and model software releases (CMS-HCC V28), applied to the FY 2026 ICD-10-CM code set. ICD List is not affiliated with CMS.
