Summary & Overview
CPT 88263: Chromosome Analysis (Karyotype) with 45-Cell Mosaic Count
CPT code 88263 represents a cytogenetic chromosome analysis (karyotype) in which an analyst examines genetic material, counts 45 cells for mosaicism, and prepares two banded karyotypes. This diagnostic laboratory procedure is central to identifying chromosomal abnormalities, including mosaic conditions, and informs genetic counseling, prenatal assessment, oncology, and certain developmental evaluations nationwide.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find clinical context for when a 45-cell mosaic count and banded karyotypes are performed, how this service fits into laboratory workflows and sites of service, and the typical coding description used in claims. The publication provides benchmarks and coverage considerations relevant to these major payers, outlines common billing and documentation elements, and highlights policy updates and payer-specific clarifications when available.
The analysis is organized to give clinicians, billing professionals, and policy stakeholders a concise reference: what the code denotes, where the service is provided, payer coverage landscape, and implications for coding and documentation. Data not available in the input will be noted where relevant.
Billing Code Overview
CPT code 88263 describes a chromosome analysis (karyotype) performed by an analyst that includes counting 45 cells for mosaicism and producing two banded karyotypes (photographic representations of chromosomes). This service involves microscopic examination of a patient’s genetic material to detect chromosomal abnormalities and to document chromosome structure and number.
Service type: Cytogenetic laboratory analysis
Typical site of service: Clinical laboratory or hospital laboratory (anatomic pathology/cytogenetics lab)
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 28-year-old pregnant woman is referred to a clinical cytogenetics laboratory after a noninvasive prenatal screening result showing possible chromosomal mosaicism. The specimen is an amniotic fluid sample collected in the obstetrics clinic and sent to the cytogenetics lab. A laboratory analyst performs a full chromosome analysis with banded karyotyping and counts 45 cells to evaluate for mosaicism; two representative karyotype images are created and interpreted. The workflow includes specimen accessioning, cell culture (if required), metaphase preparation, G-banding, microscopic analysis counting 45 mitotic cells for mosaicism assessment, photographic documentation of two karyotypes, and generation of a final report transmitted to the ordering obstetrician and maternal–fetal medicine specialist.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
11 | Professional component | When reporting the professional interpretation and report by the laboratory analyst or pathologist separate from technical services |
26 | Professional component | Alternate billing for the professional interpretation portion when billing is split between entities |