205 Form

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Medical Policy Hematopoietic Cell Transplantation for CNS Embryonal Tumors and Ependymoma Table of Contents • Policy: Commercial • Coding Information
• Information Pertaining to All Policies
• Policy: Medicare • Description
• References
• Authorization Information • Policy History

Policy Number: 205

BCBSA Reference Number: 8.01.28 (For Plan internal use only) NCD/LCD: NA Related Policies
• Hematopoietic Cell Transplantation for Solid Tumors of Childhood, #208 Policy Commercial Members: Managed Care (HMO and POS), PPO, and Indemnity
Medicare HMO BlueSM and Medicare PPO BlueSM Members

EMBRYONAL TUMORS OF THE CENTRAL NERVOUS SYSTEM

Autologous Hematopoietic Cell Transplantation
Autologous hematopoietic cell transplantation may be considered MEDICALLY NECESSARY as consolidation therapy for previously untreated embryonal tumors of the central nervous system (CNS) that show partial or complete response to induction chemotherapy, or stable disease after induction therapy.

Autologous hematopoietic cell transplantation may be MEDICALLY NECESSARY to treat recurrent embryonal tumors of the CNS.

Tandem autologous hematopoietic cell transplantation is INVESTIGATIONAL to treat embryonal tumors of the CNS.

Allogeneic Hematopoietic Cell Transplantation Allogeneic hematopoietic cell transplantation is INVESTIGATIONAL to treat embryonal tumors of the CNS.

EPENDYMOMA Autologous, tandem autologous, and allogeneic hematopoietic cell transplantation is INVESTIGATIONAL to treat ependymoma.

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Prior Authorization Information
Inpatient • For services described in this policy, precertification/preauthorization IS REQUIRED for all products if the procedure is performed inpatient.
Outpatient • For services described in this policy, see below for products where prior authorization might be required if the procedure is performed outpatient.

Outpatient Commercial Managed Care (HMO and POS) Prior authorization is required. Commercial PPO and Indemnity Prior authorization is required. Medicare HMO BlueSM Prior authorization is required. Medicare PPO BlueSM Prior authorization is required.

Requesting Prior Authorization Using Authorization Manager Providers will need to use Authorization Manager to submit initial authorization requests for services. Authorization Manager, available 24/7, is the quickest way to review authorization requirements, request authorizations, submit clinical documentation, check existing case status, and view/print the decision letter. For commercial members, the requests must meet medical policy guidelines.
To ensure the service request is processed accurately and quickly: • Enter the facility’s NPI or provider ID for where services are being performed. • Enter the appropriate surgeon’s NPI or provider ID as the servicing provider, not the billing group.

Authorization Manager Resources Refer to our Authorization Manager page for tips, guides, and video demonstrations. CPT Codes / HCPCS Codes / ICD Codes Inclusion or exclusion of a code does not constitute or imply member coverage or provider reimbursement. Please refer to the member’s contract benefits in effect at the time of service to determine coverage or non-coverage as it applies to an individual member.

Providers should report all services using the most up-to-date industry-standard procedure, revenue, and diagnosis codes, including modifiers where applicable.

The following codes are included below for informational purposes only; this is not an all-inclusive list.

The above medical necessity criteria MUST be met for the following codes to be covered for Commercial Members: Managed Care (HMO and POS), PPO, Indemnity, Medicare HMO Blue and Medicare PPO Blue: CPT codes CPT codes:

Code Description HCPCS Codes HCPCS codes: Code Description S2150 Bone marrow or blood-derived peripheral stem-cell harvesting and transplantation, allogeneic or autologous, including pheresis, high-dose chemotherapy, and the number of days of post-transplant care in the global definition (including drugs; hospitalization; medical surgical, diagnostic and emergency services)

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Description Central Nervous System Embryonal Tumors Classification of brain tumors is based on both histopathologic characteristics of the tumor and location in the brain. Central nervous system (CNS) embryonal tumors are more common in children and are the most common brain tumor in childhood. Medulloblastomas account for 20% of all childhood CNS tumors. Recurrent childhood CNS embryonal tumors are not uncommon and, depending on which type of treatment the patient initially received, autologous hematopoietic cell transplantation (HCT) may be an option. For patients who receive high-dose chemotherapy and autologous HCT for recurrent embryonal tumors, the objective response is 50% to 75%; however, long-term disease control is obtained in fewer than 30% of patients and is primarily seen in patients with a first relapse of localized disease at the time of the relapse.1,

Ependymoma Ependymoma is a neuroepithelial tumor that arises from the ependymal lining cell of the ventricles and is, therefore, usually contiguous with the ventricular system. An ependymoma tumor typically arises intracranially in children, while in adults a spinal cord location is more common. Ependymomas have access to the cerebrospinal fluid and may spread throughout the entire neuroaxis. Ependymomas are distinct from ependymoblastomas due to their more mature histologic differentiation. Hematopoietic Cell Transplantation Hematopoietic cell transplantation is a procedure in which hematopoietic stem cells are intravenously infused to restore bone marrow and immune function in with cancer who receive bone marrow-toxic doses of cytotoxic drugs with or without whole-body radiotherapy. Hematopoietic stem cells may be obtained from the transplant recipient (autologous HCT) or a donor (allogeneic HCT [allo-HCT]). These cells can be harvested from bone marrow, peripheral blood, or umbilical cord blood shortly after delivery of neonates.
Immunologic compatibility between infused hematopoietic stem cells and the recipient is not an issue in autologous HCT. In allo-HCT, immunologic compatibility between donor and patient is a critical factor for achieving a successful outcome. Compatibility is established by typing of human leukocyte antigens (HLA) using cellular, serologic, or molecular techniques. HLA refers to the gene complex expressed at the HLA- A, -B, and -DR (antigen-D related) loci on each arm of chromosome 6. An acceptable donor will match the patient at all or most of the HLA loci. Conditioning for Hematopoietic Cell Transplantation

Conventional Conditioning The conventional (“classical”) practice of allo-HCT involves administration of cytotoxic agents (e.g., cyclophosphamide, busulfan) with or without total body irradiation at doses sufficient to cause bone marrow ablation in the recipient. The beneficial treatment effect of this procedure is due to a combination of the initial eradication of malignant cells and subsequent graft-versus-malignancy effect mediated by non-self- immunologic effector cells. While the slower graft-versus-malignancy effect is considered the potentially curative component, it may be overwhelmed by existing disease in the absence of pretransplant conditioning. Intense conditioning regimens are limited to patients who are sufficiently medically fit to tolerate substantial adverse effects. These include opportunistic infections secondary to loss of endogenous bone marrow function and organ damage or failure caused by cytotoxic drugs. Subsequent to graft infusion in allo-HCT, immunosuppressant drugs are required to minimize graft rejection and graft- versus-host disease (GVHD), which increases susceptibility to opportunistic infections. The success of autologous HCT is predicated on the potential of cytotoxic chemotherapy, with or without radiotherapy, to eradicate cancerous cells from the blood and bone marrow. This permits subsequent engraftment and repopulation of the bone marrow with presumably normal hematopoietic stem cells obtained from the patient before undergoing bone marrow ablation. Therefore, autologous HCT is typically performed as consolidation therapy when the patient’s disease is in complete remission. Patients who

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undergo autologous HCT are also susceptible to chemotherapy-related toxicities and opportunistic infections before engraftment, but not GVHD. Reduced-Intensity Conditioning Allogeneic Hematopoietic Cell Transplantation Reduced-intensity conditioning (RIC) refers to the pretransplant use of lower doses of cytotoxic drugs or less intense regimens of radiotherapy than are used in traditional full-dose myeloablative conditioning treatments. Although the definition of RIC is variable, with numerous versions employed, all regimens seek to balance the competing effects of relapse due to residual disease and non-relapse mortality. The goal of RIC is to reduce disease burden and to minimize associated treatment-related morbidity and non- relapse mortality in the period during which the beneficial graft-versus-malignancy effect of allogeneic transplantation develops. Reduced-intensity conditioning regimens range from nearly total myeloablative to minimally myeloablative with lymphoablation, with intensity tailored to specific diseases and patient condition. Patients who undergo RIC with allo-HCT initially demonstrate donor cell engraftment and bone marrow mixed chimerism. Most will subsequently convert to full-donor chimerism. In this review, the term reduced-intensity conditioning will refer to all conditioning regimens intended to be nonmyeloablative. Autologous HCT allows for the escalation of chemotherapy doses above those limited by myeloablation and has been tried in patients with high-risk brain tumors in an attempt to eradicate residual tumor cells and improve cure rates. The use of allo-HCT for solid tumors does not rely on the escalation of chemotherapy intensity and tumor reduction but rather on a graft-versus-tumor effect. Allo-HCT is not commonly used in solid tumors and may be used if an autologous source cannot be cleared of a tumor or cannot be harvested. Summary High-dose chemotherapy with hematopoietic cell transplantation (HCT) has been investigated as a possible therapy in pediatric individuals with brain tumors, particularly in those with high-risk disease. The use of HCT has allowed for a reduction in the dose of radiation needed to treat both average- and high- risk disease with a goal of preserving the quality of life and intellectual functioning. For individuals who have newly diagnosed central nervous system (CNS) embryonal tumors who receive autologous hematopoietic cell transplantation (HCT), the evidence includes prospective and retrospective studies. Relevant outcomes are overall survival (OS), disease-specific survival (DSS), and treatment- related mortality and morbidity. For pediatric CNS embryonal tumors, an important consideration is whether the use of HCT may allow for a reduction in radiation dose. Data from single-arm studies using high-dose chemotherapy with autologous HCT to treat newly diagnosed CNS embryonal tumors have shown comparable or improved survival (both event-free survival [EFS] and OS) compared with historical controls treated with conventional therapy, with or without radiotherapy, particularly in patients with a disease considered high-risk. In a retrospective comparative study, survival in patients receiving high- dose chemotherapy with HCT and delayed craniospinal irradiation (CSI) was comparable with survival in those receiving upfront CSI. Overall, data from these observational studies have suggested HCT may allow reduced doses of CSI without worsening survival outcomes. The evidence is sufficient to determine that the technology results in an improvement in the net health outcome. For individuals who have recurrent or relapsed CNS embryonal tumors who receive autologous HCT, the evidence includes prospective and retrospective single-arm studies and a systematic review of these studies. Relevant outcomes are OS, DSS, and treatment-related mortality and morbidity. For recurrent/relapsed CNS embryonal tumors, survival outcomes after HCT vary, and survival is generally very poor for tumors other than medulloblastoma. Data from some single-arm studies using autologous HCT to treat recurrent CNS embryonal tumors have shown comparable or improved survival compared with historical controls treated with conventional therapy for certain patients. The results of a 2012 systematic review of observational studies in patients with relapsed supratentorial primitive neuroectodermal tumor (PNET) suggested that a subgroup of infants with the chemosensitive disease might benefit from autologous HCT, achieving survival without the use of radiotherapy, whereas outcomes in older children and/or in the pineal location are poor with this modality. However, a relatively large prospective multicenter study has reported that HCT was not associated with improved survival outcomes in patients who had a good response to therapy. Overall, data from these single-arm studies

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have suggested HCT may be associated with improved survival outcomes in select patients, although data for some tumor types are limited (eg, atypical teratoid/rhabdoid tumors). The evidence is sufficient to determine that the technology results in an improvement in the net health outcome. For individuals who have CNS embryonal tumors who receive tandem autologous HCT, the evidence includes prospective and retrospective single-arm studies. Relevant outcomes are OS, DSS, and treatment-related mortality and morbidity. Less evidence specifically addresses the use of tandem autologous HCT for CNS embryonal tumors. The available single-arm studies are very small but appear to report OS and EFS rates comparable with single autologous HCT. Tandem transplants might allow reduced doses of craniospinal irradiation, with the goal of avoiding long-term radiation damage. However, most studies used standard-dose irradiation, making the relative benefit of tandem autologous HCT uncertain. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome. For individuals who have CNS embryonal tumors who receive allogeneic HCT, the evidence includes case reports. Relevant outcomes are OS, DSS, and treatment-related mortality and morbidity. The available evidence is limited. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome. For individuals who have ependymoma who receive autologous HCT, the evidence includes relatively small case series. Relevant outcomes are OS, DSS, and treatment-related mortality and morbidity. The available case series do not report higher survival rates for patients with ependymoma treated with HCT compared with standard therapies. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome. Policy History Date Action 3/2026 Annual policy review. Policy updated with literature review through December 10, 2025; no references added. 10/2025 Clarified coding information. 3/2025 Annual policy review. References updated. Policy statements unchanged. 3/2024 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 9/2023 Policy clarified to include prior authorization requests using Authorization Manager.
3/2023 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 2/2022 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 3/2021 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 10/2020 Clarified coding information 4/2020 Bone marrow harvesting codes were removed. Outpatient prior authorization is not required.
3/2020 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 3/2019 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 1/2019 Outpatient prior authorization is required for all commercial products including Medicare Advantage. Effective 1/1/2019. 2/2018 Annual policy review. New references added. Clarified coding information. 3/2017 Annual policy review. Title changed. New references added. 3/1/2017 3/2016 Annual policy review. New references added. 9/2015 Clarified coding information.

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12/2014 Annual policy review. New references added. 6/2014 Updated Coding section with ICD10 procedure and diagnosis codes, effective 10/2015. 2/2014 Annual policy review. New references added. 12/2012 Updated to add new CPT code 38243. 11/2011-4/2012 Medical policy ICD 10 remediation: Formatting, editing and coding updates. No changes to policy statements.
7/2011 Reviewed - Medical Policy Group – Hematology and Oncology. No changes to policy statements. 5/2011 Reviewed - Medical Policy Group - Pediatrics and Endocrinology. No changes to policy statements. 9/2010 Reviewed - Medical Policy Group - Hematology and Oncology. No changes to policy statements. 8/1/2010 Medical Policy 205 effective 8/1/10. Information Pertaining to All Blue Cross Blue Shield Medical Policies Click on any of the following terms to access the relevant information: Medical Policy Terms of Use Managed Care Guidelines Indemnity/PPO Guidelines Clinical Exception Process Medical Technology Assessment Guidelines

References

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26. Egan G, Cervone KA, Philips PC, et al. Phase I study of temozolomide in combination with thiotepa and carboplatin with autologous hematopoietic cell rescue in patients with malignant brain tumors with minimal residual disease. Bone Marrow Transplant. Apr 2016; 51(4): 542-5. PMID 26726947
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29. Sung KW, Lim DH, Son MH, et al. Reduced-dose craniospinal radiotherapy followed by tandem high- dose chemotherapy and autologous stem cell transplantation in patients with high-risk medulloblastoma. Neuro Oncol. Mar 2013; 15(3): 352-9. PMID 23258845
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31. Park ES, Sung KW, Baek HJ, et al. Tandem high-dose chemotherapy and autologous stem cell transplantation in young children with atypical teratoid/rhabdoid tumor of the central nervous system. J Korean Med Sci. Feb 2012; 27(2): 135-40. PMID 22323859
32. Sung KW, Yoo KH, Cho EJ, et al. High-dose chemotherapy and autologous stem cell rescue in children with newly diagnosed high-risk or relapsed medulloblastoma or supratentorial primitive neuroectodermal tumor. Pediatr Blood Cancer. Apr 2007; 48(4): 408-15. PMID 17066462
33. Lundberg JH, Weissman DE, Beatty PA, et al. Treatment of recurrent metastatic medulloblastoma with intensive chemotherapy and allogeneic bone marrow transplantation. J Neurooncol. Jun 1992; 13(2): 151-5. PMID 1432032
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39. Grill J, Kalifa C, Doz F, et al. A high-dose busulfan-thiotepa combination followed by autologous bone marrow transplantation in childhood recurrent ependymoma. A phase-II study. Pediatr Neurosurg. Jul 1996; 25(1): 7-12. PMID 9055328
40. Zacharoulis S, Levy A, Chi SN, et al. Outcome for young children newly diagnosed with ependymoma, treated with intensive induction chemotherapy followed by myeloablative chemotherapy and autologous stem cell rescue. Pediatr Blood Cancer. Jul 2007; 49(1): 34-40. PMID 16874765
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42. Kanate AS, Majhail NS, Savani BN, et al. Indications for Hematopoietic Cell Transplantation and Immune Effector Cell Therapy: Guidelines from the American Society for Transplantation and Cellular Therapy. Biol Blood Marrow Transplant. Jul 2020; 26(7): 1247-1256. PMID 32165328
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