# CPT 88189

> Medicare paid $85.14 for CPT 88189 in the office (non-facility) setting and $85.14 in a facility under the Q3 2021 Physician Fee Schedule, effective July 2021. These are the national allowed amounts before the ~2% sequestration cut and before locality (GPCI) adjustment. This price has been unchanged since Q1 2021, when it decreased 4.1%.

## What it is

The pathologist's read of a flow cytometry study, where cells from blood, bone marrow, or a lymph node are tagged with fluorescent antibodies and sorted one at a time by a laser instrument. This code covers the physician work of interpreting the resulting pattern of cell-surface markers and writing the diagnostic report; the laboratory work of running the samples is captured by separate codes. It sits at the top of a graded family split by how many markers were examined, and applies to the largest panels, sixteen markers or more, rather than the smaller panels covered by its two sibling codes.

## Selected release

- Release: Q3 2021 (2021 C)
- Effective: July 1 – September 30, 2021
- Status indicator: A
- Office (non-facility) national allowed amount: $85.14
- Facility national allowed amount: $85.14
- Sequestration: not applied

## RVUs and formula

- Work RVU: 1.70
- Office (non-facility) practice expense RVU: 0.65
- Facility practice expense RVU: 0.65
- Malpractice RVU: 0.09
- Conversion factor: 34.8931
- Formula: `(work_rvu × work_gpci + pe_rvu × pe_gpci + mp_rvu × mp_gpci) × conversion_factor`

## Source and citation

- Source: Physician relative value file (Q3 2021)
- CMS file: https://www.cms.gov/files/zip/rvu21c-updated-6302021.zip
- Parsed file: PPRRVU21_JUL.csv, row 15,477
- Canonical page: https://localishealth.com/cpt/88189/2021/A
- Release-specific citation URL: https://localishealth.com/cpt/88189/2021/C
- Last significant update: 2026-08-04T03:10:45+00:00