Summary & Overview

CPT 0332U: EpiSwitch CiRT Checkpoint‑inhibitor Response Test

CPT code 0332U designates a Proprietary Laboratory Analyses (PLA) test, EpiSwitch® CiRT, that measures eight epigenetic biomarkers in whole blood to help characterize likely patient response to immune checkpoint inhibitor therapies. As a PLA code, 0332U is tied to a single test offered by specific manufacturers/labs and signals a precision diagnostic used in oncology care. Nationally, such PLA codes matter because they standardize reporting and tracking for unique commercial tests and affect coverage discussions for precision oncology.

Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical purpose of the test, typical sites of service, and the payer landscape relevant to adoption and reimbursement. The publication also summarizes expected benchmarks and policy considerations affecting proprietary laboratory tests, outlines common billing modifiers used in practice, and provides clinical context on how this assay fits into the diagnostic pathway for patients considered for immune checkpoint inhibitor therapy.

This executive summary is written for a national audience and focuses on the billing code definition, payer coverage environment, and what stakeholders need to know about clinical and policy implications for CPT code 0332U.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare0332UCPTProprietary Laboratory AnalysesEpiSwitchepigenetic biomarkersoncology diagnosticsimmune checkpoint inhibitorslaboratory testingprecision medicine

Billing Code Overview

CPT code 0332U is a Proprietary Laboratory Analyses (PLA) code for the EpiSwitch® CiRT (Checkpoint–inhibitor Response Test) developed by Next Bio–Research Services LLC and Oxford BioDynamics PLC. The test uses a whole blood specimen from a cancer patient to identify and quantify eight epigenetic biomarkers that may influence response to immune checkpoint inhibitor therapies. This PLA code is specific to that single proprietary laboratory test.

Service type: Laboratory diagnostic test — proprietary epigenetic biomarker assay
Typical site of service: Clinical laboratory using a patient whole blood specimen

Clinical & Coding Specifications

Clinical Context

A 62-year-old patient with advanced non-small cell lung cancer (NSCLC) under consideration for immune checkpoint inhibitor therapy presents for biomarker evaluation. The oncologist orders the EpiSwitch® CiRT assay (0332U) performed on a whole blood specimen to assess eight epigenetic biomarkers associated with response to PD-1/PD-L1 or CTLA-4 inhibitors. Blood is collected in a phlebotomy or infusion clinic (typical site of service: outpatient laboratory, hospital outpatient, or oncology clinic), labeled and shipped per the manufacturer's protocol to Next Bio-Research Services LLC / Oxford BioDynamics PLC for proprietary laboratory analysis. Results return to the ordering oncologist and are reviewed during a treatment planning visit to inform the decision to initiate, continue, or modify immune checkpoint inhibitor therapy.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when billing only the professional interpretation component if applicable and billed separately (rare for PLAs).
`TC`	Technical component	Use when billing only the technical component of the test (laboratory processing) when professional interpretation is billed separately.
`QK`	CLIA waived test performed by lab director/owner	Use when applicable contractual or regulatory reporting requires CLIA-related modifier reporting for lab personnel combinations.
`QX`	Rendering provider in private practice	Use when the performing or ordering laboratory has outpatient rendering provider reporting requirements.
`QY`	Laboratory test performed by an independent laboratory	Use when the test is performed by an independent clinical laboratory rather than the ordering provider's facility.
`62`	Two surgeons or two physicians	Use if two physicians from different specialties are involved in interpretation decisions requiring separate billing roles (rare).
`52`	Reduced services	Use when the test is partially performed or a reduced panel is completed relative to the full test.
`53`	Discontinued procedure	Use if testing was started but aborted for clinical or specimen-quality reasons prior to completion.
`78`	Unplanned return to the operating/procedure room	Not typically applicable; include only if a procedural complication requires immediate additional testing in the operative setting.
`80`	Assistant surgeon	Not typically applicable; include only if an assistant clinician is separately billing for a role tied to specimen procurement.
`AS`	Physician assistant, nurse practitioner, or clinical nurse specialist services	Use when advanced practice clinicians perform specimen collection or ordering under appropriate supervision and payor rules require the modifier.
`FY`	Ordering physician differs from performing physician	Use when the ordering clinician and the laboratory performing the test are different entities and payor reporting requires identification.
`QY`	Laboratory test performed by an independent laboratory	Use when the assay is supplied and run by an independent commercial laboratory (applicable for this proprietary PLA).
`TJ`	Data not in input — omitted	Data not available in the input.

Taxonomy Code	Specialty	Notes
208000000X	Hematology & Oncology	Ordering and interpreting physicians who manage checkpoint inhibitor therapy.
207RC0000X	Medical Oncology	Specialists who commonly order tumor response and predictive biomarker testing.
261QE0010X	Clinical Laboratory	Laboratory directors and pathologists overseeing performance of proprietary lab assays.
207L00000X	Medical Genetics	Specialists who may consult on interpretation of complex biomarker panels.
2086S0102X	Surgical Oncology	Surgeons involved in multidisciplinary care who may order or act on results in some cases.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`C34.90`	Malignant neoplasm of unspecified part of bronchus or lung, unspecified laterality	Lung cancer patients are common candidates for checkpoint inhibitor therapy and for whom `0332U` may be ordered.
`C50.919`	Malignant neoplasm of unspecified site of unspecified female breast	Metastatic or advanced breast cancers considered for immune checkpoint inhibitors in select contexts may prompt epigenetic response testing.
`C61`	Malignant neoplasm of prostate	Prostate cancer in certain advanced settings may be assessed for immunotherapy suitability using specialized biomarkers.
`C18.9`	Malignant neoplasm of colon, unspecified	Colorectal cancers, particularly MSI-high or immune-responsive subsets, may be evaluated with additional biomarkers including epigenetic assays.
`C80.1`	Malignant (primary) neoplasm, unspecified	Advanced or metastatic cancers of unknown primary considered for systemic immune therapy may undergo comprehensive biomarker panels including `0332U`.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36415`	Collection of venous blood by venipuncture	Commonly performed immediately prior to `0332U` to obtain the whole blood specimen sent to the laboratory.
`86328`	Immunoassay for infectious agent antibody(ies)	Representative of laboratory immunoassay processes; not the same as PLA but conceptually analogous for lab workflow billing distinctions.
`88360`	Morphometric analysis or digital pathology; interpretation (per specimen)	Used when additional pathology review or digital analysis is performed alongside molecular or epigenetic testing interpretations.
`81162`	BRCA1 and BRCA2 analysis, full sequence (example of molecular testing)	Example of molecular/genetic testing codes commonly billed in the broader oncology biomarker workup; may be ordered in parallel with `0332U`.
`0054U`	Another PLA test (example)	Represents other Proprietary Laboratory Analyses that may be ordered in conjunction with `0332U` in comprehensive biomarker profiling.

Beta

OpenPayer Beta

Summary & Overview

CPT 0332U: EpiSwitch CiRT Checkpoint‑inhibitor Response Test

Billing Code Overview

Service type: Laboratory diagnostic test — proprietary epigenetic biomarker assay
Typical site of service: Clinical laboratory using a patient whole blood specimen

Clinical & Coding Specifications

Clinical Context

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when billing only the professional interpretation component if applicable and billed separately (rare for PLAs).
`TC`	Technical component	Use when billing only the technical component of the test (laboratory processing) when professional interpretation is billed separately.
`QK`	CLIA waived test performed by lab director/owner	Use when applicable contractual or regulatory reporting requires CLIA-related modifier reporting for lab personnel combinations.
`QX`	Rendering provider in private practice	Use when the performing or ordering laboratory has outpatient rendering provider reporting requirements.
`QY`	Laboratory test performed by an independent laboratory	Use when the test is performed by an independent clinical laboratory rather than the ordering provider's facility.
`62`	Two surgeons or two physicians	Use if two physicians from different specialties are involved in interpretation decisions requiring separate billing roles (rare).
`52`	Reduced services	Use when the test is partially performed or a reduced panel is completed relative to the full test.
`53`	Discontinued procedure	Use if testing was started but aborted for clinical or specimen-quality reasons prior to completion.
`78`	Unplanned return to the operating/procedure room	Not typically applicable; include only if a procedural complication requires immediate additional testing in the operative setting.
`80`	Assistant surgeon	Not typically applicable; include only if an assistant clinician is separately billing for a role tied to specimen procurement.
`AS`	Physician assistant, nurse practitioner, or clinical nurse specialist services	Use when advanced practice clinicians perform specimen collection or ordering under appropriate supervision and payor rules require the modifier.
`FY`	Ordering physician differs from performing physician	Use when the ordering clinician and the laboratory performing the test are different entities and payor reporting requires identification.
`QY`	Laboratory test performed by an independent laboratory	Use when the assay is supplied and run by an independent commercial laboratory (applicable for this proprietary PLA).
`TJ`	Data not in input — omitted	Data not available in the input.

Taxonomy Code	Specialty	Notes
208000000X	Hematology & Oncology	Ordering and interpreting physicians who manage checkpoint inhibitor therapy.
207RC0000X	Medical Oncology	Specialists who commonly order tumor response and predictive biomarker testing.
261QE0010X	Clinical Laboratory	Laboratory directors and pathologists overseeing performance of proprietary lab assays.
207L00000X	Medical Genetics	Specialists who may consult on interpretation of complex biomarker panels.
2086S0102X	Surgical Oncology	Surgeons involved in multidisciplinary care who may order or act on results in some cases.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`C34.90`	Malignant neoplasm of unspecified part of bronchus or lung, unspecified laterality	Lung cancer patients are common candidates for checkpoint inhibitor therapy and for whom `0332U` may be ordered.
`C50.919`	Malignant neoplasm of unspecified site of unspecified female breast	Metastatic or advanced breast cancers considered for immune checkpoint inhibitors in select contexts may prompt epigenetic response testing.
`C61`	Malignant neoplasm of prostate	Prostate cancer in certain advanced settings may be assessed for immunotherapy suitability using specialized biomarkers.
`C18.9`	Malignant neoplasm of colon, unspecified	Colorectal cancers, particularly MSI-high or immune-responsive subsets, may be evaluated with additional biomarkers including epigenetic assays.
`C80.1`	Malignant (primary) neoplasm, unspecified	Advanced or metastatic cancers of unknown primary considered for systemic immune therapy may undergo comprehensive biomarker panels including `0332U`.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36415`	Collection of venous blood by venipuncture	Commonly performed immediately prior to `0332U` to obtain the whole blood specimen sent to the laboratory.
`86328`	Immunoassay for infectious agent antibody(ies)	Representative of laboratory immunoassay processes; not the same as PLA but conceptually analogous for lab workflow billing distinctions.
`88360`	Morphometric analysis or digital pathology; interpretation (per specimen)	Used when additional pathology review or digital analysis is performed alongside molecular or epigenetic testing interpretations.
`81162`	BRCA1 and BRCA2 analysis, full sequence (example of molecular testing)	Example of molecular/genetic testing codes commonly billed in the broader oncology biomarker workup; may be ordered in parallel with `0332U`.
`0054U`	Another PLA test (example)	Represents other Proprietary Laboratory Analyses that may be ordered in conjunction with `0332U` in comprehensive biomarker profiling.