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 HCC 454 neither supersedes nor is superseded by any other category, so it always counts alongside unrelated HCCs.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. 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.
