This policy is designed to address medical guidelines that are appropriate for the majority of individuals with a particular disease, illness, or condition. Each person's unique clinical circumstances may warrant individual consideration, based on review of applicable medical records.

This policy addresses common clinical applications of flow cytometry-based tests that are billed using CPT codes 88184-88189. It is not intended to encompass flow cytometry-based tests billed using more specific CPT codes (e.g., 86355-86367, 86828- 86835).

Hematopoietic Neoplasm Evaluation and Monitoring

Flow cytometry markers used to evaluate a sample are necessarily different based on clinical indication, information from other evaluations (e.g., morphology), sample type, and the laboratory setting, this policy addresses general principles of marker panel selection.

Flow cytometry may be considered medically necessary for the following indications:

• In the initial evaluation of suspected hematopoietic neoplasm:
  • Common non-neoplastic causes of the clinical presentation (e.g., infection or asplenia with leukocytosis, etc.) should be reasonably ruled out before flow cytometry is employed; and
  • A limited but sufficient number of markers should be used in the initial evaluation that allows identification of all major categories of neoplasia (B, T, myeloid, or plasma cell lineages) under consideration based on the clinical indication; and
  • Testing with additional markers is indicated to further characterize disease when the initial evaluation is suggestive.
• For staging or evaluating residual disease in patients with a known diagnosis of hematopoietic neoplasm, a limited panel of markers characteristic of that neoplasm should be used.

Testing:
Most presentations, even non-specific indications that require evaluation of several lineages (e.g., anemia, thrombocytopenia, etc.), should rarely require more than 23 flow cytometry markers and monitoring of a known hematopoietic neoplasia diagnosis requires fewer. Therefore:

• In addition to the one marker represented by CPT 88184, reimbursement will routinely be limited to 22 units of CPT 88185.
• ICD code information may be compared with units billed to identify cases with possible excess units that will require post-service medical necessity review. Expected unit number is based on the required cell lineage evaluation by medical indication outlined in the 2006 Bethesda flow cytometry guidelines.
• When a laboratory routinely bills more than an average of 14 markers, claims from that laboratory will be subject to post-service medical necessity review.

HIV Monitoring
 
Flow cytometry may be considered medically necessary for determining the percentage of lymphocytes that express antigens used to identify CD4+ T cells, and to directly measure absolute T cell counts in the case of single-platform technology (SPT); and

• Four antibodies are routinely required (CD45, CD3, CD4, CD8), which may be applied in three- or four-color antibody panels; and
• For pediatric patients, additional antibodies may be required to determine CD19+ B-cell values, which is an indicator of immune status in this population.

Testing:

• The most commonly required flow cytometry studies for HIV are represented by marker-specific CPT codes (e.g., 86355-86367). The non-specific flow cytometry codes should not be used when a more specific code exists.
• The non-specific CPT codes addressed in this policy should not routinely be required for HIV monitoring. Post-service medical necessity review may be employed when such codes are used for HIV monitoring as indicated by the attached ICD codes.

Non-Covered Indications
 
Flow cytometry procedures are not covered for the evaluation of the following indications:

• Detection of sexually transmitted organisms, such as human papillomavirus; and
• Hypertension or cardiovascular disease risk.

Testing: Flow cytometry will not be reimbursed when billed with any of the ICD10 Codes in the diagnosis code attachment indicating testing for STIs and/or indicating testing for hypertension or cardiovascular disease.

Other Clinical Indications

Flow cytometry has a variety of applications that cannot all be adequately addressed by policy. All flow cytometry studies may be considered medically necessary when performed for well validated indications.
 
Testing: When flow cytometry is billed with ICD codes that do not suggest one of the other clinical indications addressed in this policy, post-service medical necessity review may be employed.

Flow cytometry is typically an outpatient procedure which is only eligible for coverage as an inpatient procedure in special circumstances, including, but not limited to, the presence of a co-morbid condition that would require monitoring in a more controlled environment such as the inpatient setting.

Services that do not meet the criteria of this policy will not be considered medically necessary. A network provider cannot bill the member for the denied service unless: (a) the provider has given advance written notice, informing the member that the service may be deemed not medically necessary; (b) the member is provided with an estimate of the cost; and (c) the member agrees in writing to assume financial responsibility in advance of receiving the service. The signed agreement must be maintained in the provider’s records.

A network provider can bill the member for the non-covered service.

• Link to Diagnosis Codes

• Link to References