Summary & Overview
CPT 0174U: LC–MS/MS Targeted Proteomic Assay for FFPE Solid Tumors
CPT code 0174U identifies a proprietary LC–MS/MS Targeted Proteomic Assay from OncoOmicDx Laboratory that quantifies 30 proteins in FFPE tissue of solid organ tumors. As a PLA (Proprietary Laboratory Analyses) code, 0174U applies exclusively to a single, manufacturer-specific laboratory test, which has implications for coding specificity, payer recognition, and clinical reporting. Nationally, PLA codes like 0174U are important for capturing advanced, proprietary diagnostics used in oncology and precision medicine.
Key payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the code's clinical purpose, typical site of service, and service type, along with payer coverage considerations and common billing modifiers. The publication provides benchmarks and policy context relevant to proprietary laboratory tests, including coding guidance, payer coverage patterns, and operational considerations for laboratories and billing teams.
This summary is intended for a national audience of laboratory managers, coding and billing professionals, and oncology clinicians seeking a clear explanation of what CPT code 0174U represents and how it is positioned within current diagnostic and reimbursement frameworks.
Billing Code Overview
CPT code 0174U is a Proprietary Laboratory Analyses (PLA) code for the LC–MS/MS Targeted Proteomic Assay performed by OncoOmicDx Laboratory. The test uses liquid chromatography–mass spectrometry (LC–MS/MS) to quantify a panel of 30 proteins from formalin–fixed paraffin–embedded (FFPE) tissue of solid organ tumors. This assay is specific to a single manufacturer's laboratory-developed test and the CPT PLA designation indicates that the code maps to one unique test.
Service type: Laboratory — specialized proteomic assay
Typical site of service: Clinical laboratory using FFPE tumor tissue (pathology/laboratory setting)
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with a newly diagnosed solid organ malignancy (for example, non-small cell lung carcinoma or colorectal adenocarcinoma) undergoes surgical resection or core needle biopsy. Formalin-fixed paraffin-embedded (FFPE) tumor tissue is submitted to the pathology lab. The OncoOmicDx Laboratory performs an LC–MS/MS targeted proteomic assay that quantifies a panel of 30 proteins to support tumor characterization, prognostic assessment, or therapeutic guidance. Typical workflow: tissue accessioning and pathology confirmation of tumor content → microdissection or enrichment of tumor cells as needed → FFPE section preparation and protein extraction → targeted LC–MS/MS analysis at OncoOmicDx Laboratory using the proprietary assay reported with PLA code 0174U → generation of a molecular proteomic report integrated with pathology findings for the treating oncologist and multidisciplinary tumor board. Typical site of service is an independent clinical reference laboratory or hospital-based molecular pathology laboratory that receives specimens collected in the outpatient clinic, ambulatory surgery center, or inpatient operating room.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | No modifier information | Rarely used; placeholder when no additional modifier applies |
22 | Increased procedural services | Use when unusually extensive specimen handling or analysis is required beyond standard assay complexity |
26 | Professional component | Use when reporting only the professional interpretation component separate from the technical assay (if applicable under payer rules) |
52 | Reduced services | Use when partial testing is performed and the full assay is not completed |
53 | Discontinued procedure | Use if the specimen cannot be processed and the assay is aborted prior to completion |
62 | Two surgeons | Generally not applicable to the laboratory assay; available if dual-surgeon specimen procurement circumstances affect billing |
78 | Unplanned return to operating/procedure room after initial procedure for a related procedure | Uncommon for lab testing; include only if a related re-operation impacts specimen collection timing/billing |
80 | Assistant surgeon | Not typical for the lab assay; apply only if an assistant surgeon's role changes billing for specimen acquisition |
82 | Assistant surgeon (when qualified resident not available) | See 80; rarely applicable to the laboratory test itself |
AD | Pathology add-on or distinct component (payer-specific) | Use when the assay represents an add-on molecular pathology test to prior services (per payer policy) |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 208000000X | Pathology | Molecular pathology and clinical laboratory directors who oversee test performance and interpretation |
| 207R00000X | Anatomic Pathology | Pathologists who review FFPE tissue and request proteomic testing |
| 208100000X | Hematology & Oncology | Medical oncologists who order tumor proteomic profiling to guide therapy |
| 207L00000X | Surgical Pathology | Surgical pathologists involved in tissue procurement and diagnosis |
| 207K00000X | Cytopathology | Cytopathologists when cytology specimens are prepared as FFPE cell blocks for proteomic analysis |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
C34.90 | Malignant neoplasm of unspecified bronchus or lung, unspecified side | Lung cancers commonly undergo molecular and proteomic profiling to guide targeted therapy selection |
C18.9 | Malignant neoplasm of colon, unspecified | Colorectal carcinomas are candidates for tumor profiling to assess prognostic and predictive markers |
C50.919 | Malignant neoplasm of unspecified site of unspecified female breast | Breast cancer tissue is commonly analyzed with proteomic or molecular assays to refine therapy |
C71.9 | Malignant neoplasm of brain, unspecified | Selected solid tumors such as gliomas may be profiled with specialized proteomic assays when tissue is available |
C80.1 | Malignant (primary) neoplasm, unspecified | Used when a malignancy is known but primary site is not specified; proteomic profiling can assist in classification |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
88305 | Level IV surgical pathology, gross and microscopic examination | Typical pathology review and diagnosis of FFPE tissue before referral to specialized proteomic testing |
88342 | Immunohistochemistry, per specimen; first single antibody stain | Performed frequently to characterize protein expression and may be used in parallel with or prior to targeted proteomic assays |
88341 | Immunohistochemistry, per specimen; each additional single antibody stain | Additional IHC stains that complement the targeted proteomic panel |
81479 | Unlisted molecular pathology procedure | Occasionally used for reporting novel or unlisted molecular tests when PLA codes are not applicable; 0174U is the specific PLA that supersedes use of unlisted code for this assay |
0000U | Data not available in the input. | Data not available in the input. |