In Vitro Chemoresistance and Chemosensitivity Assays
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Defines Oscar Health's coverage stance for in vitro laboratory assays that test tumor sensitivity or resistance to chemotherapy agents and describes applicability, limitations, and supporting background for providers seeking reimbursement.
No material clinical or coverage changes in this revision.
Coverage Criteria
Not Medically Necessary
Not medically necessary / not covered
Policy states lack of available published scientific literature confirming the tests are required and beneficial for diagnosis and treatment.
The policy explicitly excludes in vitro chemosensitivity assays and in vitro chemoresistance assays from meeting coverage criteria. Oscar Health determined these assays do not meet criteria because there is a lack of available published scientific literature confirming that the tests are required and beneficial for diagnosis or treatment. Examples cited in the policy include the histoculture drug response assay and fluorescent cytoprint assay (chemosensitivity) and extreme drug resistance (EDR) assays (chemoresistance).
Laboratory-developed tests (LDTs) used to perform chemosensitivity or chemoresistance assays are not approved or cleared by the U.S. Food and Drug Administration. Such LDTs are regulated by CMS under CLIA as high-complexity laboratory tests; laboratories developing these in-house assays must validate and perform them internally. The policy notes that FDA clearance or approval is not currently required for clinical use of LDTs, but their regulatory status may affect coverage determinations.
The policy lists representative assay types and class examples to clarify scope. Named chemosensitivity assays include the histoculture drug response assay and the fluorescent cytoprint assay. Named chemoresistance assays include extreme drug resistance (EDR) assays. The document groups these and similar proprietary or non‑proprietary platforms under the broader categories of in vitro chemosensitivity and chemoresistance testing and treats them as not meeting coverage criteria.
Applicability
Applicability depends on the member's benefit coverage and may be superseded by applicable Medicare/Medicaid regulations.
Coverage determinations should follow benefit documents and applicable state/federal rules.
Covered Indications
Oncology tumor-specific predictive testing
Examples of proprietary chemoresistance/chemosensitivity platforms and tumor types referenced in the policy (no positive coverage criteria are provided for these tests).
Providers should refer to benefit coverage and prior authorization processes; these assays are nevertheless within the class of chemosensitivity/chemoresistance tests that the policy identifies as not meeting criteria.
Not Covered
Not covered: In vitro chemosensitivity assays and in vitro chemoresistance assays do not meet coverage criteria and are considered not medically necessary due to insufficient published evidence demonstrating they are required and beneficial for patient diagnosis or treatment. This exclusion applies to the assay classes named in the policy.
Additional context: the policy highlights that many assays for predicting tumor drug response are offered as laboratory‑developed tests. Because LDTs are not FDA-approved or cleared and are regulated under CLIA as high-complexity tests, their in‑house status and lack of FDA review are factors that inform coverage determinations; providers should be aware this regulatory classification may influence reimbursement and medical‑necessity review.
Coding
| 86849 | Unlisted immunology procedure. |
| 88104 | Cytopathology, fluids, washings or brushings, except cervical or vaginal; smears with interpretation. |
| 88199 | Unlisted cytopathology procedure. |
| 88305 | Level IV - Surgical pathology, gross and microscopic examination. |
| 88313 | Special stain including interpretation and report; Group II, all other (eg, iron, trichrome), except stain for microorganisms, stains for enzyme constituents, or immunocytochemistry and immunohistochemistry. |
| 88358 | Morphometric analysis; tumor (eg, DNA ploidy). |
| 89050 | Cell count, miscellaneous body fluids (eg, cerebrospinal fluid, joint fluid), except blood. |
| 89240 | Unlisted miscellaneous pathology test. |
| 86849 | Unlisted immunology procedure. |
| 88104 | Cytopathology, fluids, washings or brushings, except cervical or vaginal; smears with interpretation. |
| 88199 | Unlisted cytopathology procedure. |
| 88305 | Level IV - Surgical pathology, gross and microscopic examination. |
| 88313 | Special stain including interpretation and report; Group II, all other (eg, iron, trichrome), except stain for microorganisms, stains for enzyme constituents, or immunocytochemistry and immunohistochemistry. |
| 88358 | Morphometric analysis; tumor (eg, DNA ploidy). |
| 89050 | Cell count, miscellaneous body fluids (eg, cerebrospinal fluid, joint fluid), except blood. |
| 89240 | Unlisted miscellaneous pathology test. |
| 0248U | Proprietary test: 3D Predict Glioma / Onco4D™ (examples listed); proprietary oncology predictive assays (PLA code). |
| 0249U | Proprietary test: Theralink® Reverse Phase Protein Array (RPPA) — proprietary oncology assay (PLA code). |
| 0435U | Proprietary test: ChemoID® (cytotoxicity assay of cancer stem cells) — proprietary oncology assay (PLA code). |
| 0525U | Proprietary test: 3D PredictTM Ovarian / ChemoID® reporting (PLA code). |
Provider Actions & Billing Guidance
Authorization depends on member benefits and medical necessity
Coverage and any authorization are determined by the member's benefit plan and medical necessity guidelines; the specific assays listed in this policy do not meet criteria and are unlikely to be approved for coverage.
- Services must meet authorization and medical necessity guidelines for the procedure, diagnosis, and member's state of residence.
- The policy states: “In vitro chemosensitivity assays … DO NOT MEET CRITERIA” and “In vitro chemoresistance assays … DO NOT MEET CRITERIA.”
Check prior authorization for PLA / unlisted pathology codes
Certain proprietary (PLA) or unlisted pathology/immunology procedure codes may require prior authorization — confirm payer-specific PA rules before ordering or billing when using these codes.
Follow authorization process and document medical necessity
Providers must follow the policy’s authorization processes and submit documentation demonstrating medical necessity; claims will be evaluated against member benefits and authorization rules.
- Oscar’s reimbursement policies require services to meet authorization and medical necessity guidelines for the procedure, diagnosis, and member's state of residence.
- Providers are responsible for accurate claims submission and documentation.
Ensure CLIA validation and in‑house performance for LDTs
Laboratory-developed tests (LDTs) are regulated under CLIA as high‑complexity tests and are not FDA‑approved or cleared; providers using LDTs must ensure compliance with CLIA validation and in‑house performance requirements.
- “These laboratory‑developed tests (LDTs) are regulated by the Centers for Medicare and Medicaid (CMS) as high‑complexity tests under the Clinical Laboratory Improvement Amendments of 1988 (CLIA '88).”
- LDTs are not approved or cleared by the U.S. Food and Drug Administration.
Provide accurate documentation and ensure LDT validation
Submit accurate, complete documentation supporting the tests performed; the laboratory performing an LDT must validate the test and retain validation records.
- Providers are responsible for submission of accurate documentation of services performed and coding according to industry standards.
- LDTs “must validate and perform in house” and are regulated as CLIA high‑complexity tests.
Include method, specimen type, and interpretive details in documentation
Documentation must support the use of an LDT or proprietary assay, including the testing method, specimen type, and interpretive report details consistent with any listed CPT/HCPCS or PLA code.
- Documentation should include method, specimen type, and interpretive report details consistent with listed CPT/HCPCS or PLA codes.
- Policy notes proprietary assays and PLA codes (e.g., ChemoID®, 3D Predict Glioma) that require appropriate supportive documentation.
Noncompliance with coding/billing may lead to denial or recoupment
Claims may be denied or payments recouped if coding, billing guidelines, or current reimbursement policies are not followed; code and documentation must align with industry standards.
- Claims should be coded per CPT, HCPCS, ICD‑10, CMS NCCI, and other industry standards.
- The policy states: “If appropriate coding/billing guidelines or current reimbursement policies are not followed, we may deny the claim and/or recoup claim payment.”
In vitro chemosensitivity and chemoresistance assays are not covered
Assays categorized as in vitro chemosensitivity or in vitro chemoresistance (including extreme drug resistance assays) do not meet criteria and are not covered under this policy.
- Policy explicitly: “In vitro chemosensitivity assays … DO NOT MEET CRITERIA.”
- Policy explicitly: “In vitro chemoresistance assays (e.g., extreme drug resistance [EDR] assays) DO NOT MEET CRITERIA.”
Ordering Requirements
Follow member benefit and authorization processes when ordering
Ordering, authorization, and coverage determinations depend on the member’s benefit coverage and medical necessity; providers must follow the payer’s authorization processes and benefit documents when ordering tests.
- “Application of criteria is dependent upon an individual's benefit coverage at the time of the request.”
- Providers should consult member benefit documents and follow authorization processes.
Order only CLIA‑validated in‑house LDTs and document validation
If ordering a laboratory‑developed test, ensure the test is validated and performed in‑house under CLIA '88 high‑complexity requirements before submission for reimbursement.
- “These laboratory‑developed tests (LDTs) are regulated … as high‑complexity tests under the Clinical Laboratory Improvement Amendments of 1988 (CLIA '88).”
- LDTs must be validated and performed in house by the laboratory.
Definitions
Background
Background: In vitro chemosensitivity and chemoresistance assays are laboratory techniques intended to evaluate how a patient’s tumor cells respond to chemotherapeutic agents ex vivo. Tumor cells are cultured outside the body and exposed to drugs to assess cell survival, death, or other viability measures; examples named in the policy include assays such as histoculture drug response and fluorescent cytoprint, as well as EDR methods. While various proprietary and non‑proprietary platforms exist, the policy notes that available published literature does not sufficiently demonstrate that using these assays to guide therapy improves diagnosis or treatment outcomes.
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