CMS Updates NCD 110.8.1: What Medicare's Stem Cell Transplantation Policy Change Means for Your Revenue Cycle

The Centers for Medicare & Medicaid Services has issued a modification to NCD 366 (formerly coded as NCD 110.8.1), its National Coverage Determination governing stem cell transplantation. This update consolidates and clarifies coverage criteria for both autologous and allogeneic procedures—including a significant 2024-effective expansion covering myelodysplastic syndromes (MDS)—and makes explicit that transplant coverage is all-or-nothing: every step in the process is covered or none are. If your facility bills for hematopoietic stem cell transplants under Medicare, this policy deserves a close read before March 12, 2026.

What Changed in CMS NCD 366: Stem Cell Transplantation

The most operationally significant clarification in this modified policy is CMS's explicit statement on bundled coverage: when bone marrow or peripheral blood stem cell transplantation is covered, all necessary steps are included in that coverage. When it is not covered, none of the steps are covered.

Those steps include mobilization, harvesting, and the actual transplant, as well as the administration of high-dose chemotherapy (HDCT) or radiotherapy given prior to the transplant. For billing teams that have historically tried to carve out individual components—particularly the chemotherapy conditioning regimen—this language closes that door firmly. If the underlying transplant indication isn't covered, the preparatory chemotherapy won't be either.

The policy also modernizes its terminology, rebranding the NCD from 110.8.1 to NCD 366, which affects how this policy appears in MAC LCDs and how you'll reference it in appeals documentation going forward.

Allogeneic HSCT: Medicare's Nationally Covered Indications

Allogeneic hematopoietic stem cell transplantation (HSCT)—procedures using a healthy donor's stem cells or bone marrow—carries the broadest covered indication list under this NCD. Here's how coverage has been established over time:

Covered effective August 1, 1978:

• Leukemia (active or in remission)
• Aplastic anemia
  (when deemed reasonable and necessary)

Covered effective June 3, 1985:

• Severe combined immunodeficiency disease (SCID)
• Wiskott-Aldrich syndrome

Covered effective March 6, 2024 — Myelodysplastic Syndromes (MDS):
This is the most consequential coverage expansion embedded in this policy. Allogeneic HSCT using bone marrow, peripheral blood, or umbilical cord blood stem cell products is now covered for Medicare patients with MDS who meet at least one of the following prognostic risk thresholds:

Documentation of the specific scoring system used and the patient's calculated score is not optional—it's the foundation of any medical necessity argument for this indication. Ensure your hematology teams are recording which tool they used and the numeric result in the clinical record.

Covered with conditions effective January 27, 2016 — Multiple Myeloma:
Allogeneic HSCT for multiple myeloma is covered only for beneficiaries who meet both of the following:

1. Durie-Salmon Stage II or III, or International Staging System (ISS) Stage II or III
2. Enrollment in an approved prospective clinical study

This is a clinical trial requirement, not a standard-of-care coverage pathway. Billing outside an approved study context for this indication will not be covered.

Autologous Stem Cell Transplantation (AuSCT): Coverage Framework

Autologous stem cell transplantation—where the patient's own previously stored cells are used—is covered under this NCD specifically when used to restore hematopoietic function following severely myelotoxic doses of chemotherapy and/or radiotherapy for malignancies. The operative phrase is "severely myelotoxic doses"—this is a medical necessity standard, not simply any chemotherapy regimen followed by reinfusion.

The clinical rationale: AuSCT exists to rescue bone marrow function destroyed by high-dose treatment that would otherwise be lethal. Coverage hinges on the therapy's purpose being curative or disease-controlling at doses requiring stem cell rescue—not on the stem cell procedure itself being the primary treatment.

Coverage vs. Non-Coverage: Understanding the All-or-Nothing Rule

The bundling language in this policy has direct billing implications that billing directors should address now:

• If a transplant indication is covered, Medicare expects a single, comprehensive claim structure covering all preparatory and procedural steps
• If the indication is not covered (e.g., an experimental use, an unstaged malignancy, a diagnosis that doesn't meet prognostic scoring thresholds), claims for the conditioning chemotherapy, mobilization agents, or harvesting procedures will also be denied
• This rule applies to both inpatient hospital services and physicians' services—both benefit categories are named in this NCD

This matters especially for cases where chemotherapy is administered days or weeks before the transplant, sometimes generating separate claims. Those claims are now explicitly linked to the transplant's coverage status.

Affected Codes

The policy as published under NCD 366 does not list specific CPT or HCPCS codes. No procedure codes appear in the policy data for this NCD version.

This is not unusual for a CMS NCD—code-level specificity is often handled downstream by Medicare Administrative Contractor (MAC) Local Coverage Determinations (LCDs) and accompanying billing articles. Billing teams should consult their regional MAC's LCD for stem cell transplantation to identify the specific procedure codes subject to this NCD's coverage rules.

What Your Billing Team Should Do