Summary & Overview
CPT 88275: Interphase FISH Analysis, 100–300 Cells
Headline: CPT code 88275: Interphase FISH Analysis of 100–300 Cells, Clinical Diagnostic Cytogenetics
Lead: CPT code 88275 denotes a molecular cytogenetic assay using interphase in situ hybridization (FISH) in which an analyst examines 100 to 300 cells. The test identifies chromosomal abnormalities without requiring dividing cells and is used across oncology, prenatal, and genetic diagnostic workflows.
What this code represents and why it matters: CPT code 88275 captures an intermediate-intensity interphase FISH procedure that quantifies signals across a substantial cell count (100–300 cells). Nationally, this level of analysis supports diagnostic certainty for chromosome-level abnormalities, informs treatment planning in hematologic and solid-tumor settings, and underpins many hereditary and prenatal evaluations.
Key payers covered: The analysis considers major national payers including Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.
What readers will learn: The publication explains the clinical context and laboratory service captured by CPT code 88275, typical sites of service, and the role of 100–300 cell interphase FISH in care pathways. It provides benchmarks and policy-relevant context where available, highlights payer coverage considerations, and summarizes implications for billing and documentation. Data not available in the input are noted where applicable.
Billing Code Overview
CPT code 88275 describes a molecular cytogenetic analysis using interphase in situ hybridization (FISH) in which the analyst evaluates 100 to 300 cells. Interphase FISH examines cells when they are not actively dividing, allowing visualization of chromosomal targets within intact nuclei rather than metaphase chromosomes.
Service type: Molecular cytogenetic diagnostic test (interphase FISH) with cell count-based analysis
Typical site of service: Clinical laboratory or hospital laboratory
Data not available in the input for payers, associated taxonomies, and ICD-10 diagnoses.
Clinical & Coding Specifications
Clinical Context
A 45-year-old patient with persistent unexplained cytopenias and an abnormal peripheral blood smear is referred for molecular cytogenetic evaluation. The hematology team orders interphase fluorescence in situ hybridization (FISH) on peripheral blood or bone marrow to evaluate for common chromosomal abnormalities such as deletions, translocations, or copy number changes associated with hematologic malignancies (for example, abnormalities involving chromosomes 5, 7, 8, 11, 17, or BCR-ABL1). The clinical workflow: the specimen (peripheral blood or bone marrow aspirate) is received in the molecular cytogenetics laboratory; technologists prepare interphase nuclei and hybridize locus-specific probes; the analyst performs microscopic or digital analysis of 100 to 300 interphase cells per probe set; results are documented in the laboratory information system and a report is issued to the ordering hematologist. The service typically occurs in an outpatient hospital laboratory, reference molecular pathology laboratory, or an academic medical center cytogenetics laboratory. Turnaround time varies by probe panel complexity and clinical urgency but is commonly 2–7 business days.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation by a physician or qualified analyst separate from the technical component |