Unnecessary FISH and Flow Cytometry: When Every Specimen Gets the Full Workup

Unnecessary FISH and flow cytometry billing charges government health care programs for testing that lacks a patient-specific medical need. The decision can disappear inside a routine panel, an automatic add-on or a referral bonus that rewards more testing. The cases below allege that taxpayers paid for the extra work while patients became a source of testing revenue. For the people handling orders, performing tests or reviewing claims, the question is concrete: who decided this patient needed each additional procedure, and where is that decision recorded?

Technical Work and Interpretation

For flow cytometry, the technical testing and the professional interpretation have distinct billing treatment, with only one interpretation code per specimen. Selecting the markers, performing the work and interpreting the findings each leave something to compare with the claim.

The Decision Before the Additional Test

Medicare’s diagnostic-test ordering rule requires the treating physician or qualified treating practitioner to order the test and use its results in managing the patient’s medical problem. The treating practitioner must keep the medical-necessity support in the patient’s record. The laboratory submitting the claim must keep the information it received and show that the claim accurately reflects it.

The evidence therefore lives in different places. The practice may hold the reason for the test. The laboratory holds the request, the work performed and the bill. We connect those records to see whether the extra procedure came from a clinical decision or from the laboratory’s routine.

Flow Cytometry Automatic Reflex Without Individualized Pathology Finding

An automatic flow-cytometry reflex needs a documented basis connecting the additional testing to this patient. Medicare’s ordering framework permits a treating practitioner to make an additional test conditional on a specified result from the first test. The condition belongs in the order. A laboratory’s standard operating procedure describes what its staff will do when a result triggers more testing. The ordering record shows whether the practitioner requested that work.

We compare the original requisition with the triggering result to see who selected the additional procedure and whether the result met the condition in the order.

Medicare’s pathology exception allows additional stains needed for a complete and accurate diagnosis when a specimen arrives with a requisition but no specific order. The pathologist must document the work and communicate it to the treating physician. The exception ties additional work to the diagnosis, not to a routine full workup on every specimen.

Standing Orders and Customized Profiles

Standing orders need continuing support for the tests they generate. The HHS Office of Inspector General’s laboratory compliance guidance says a standing order alone is usually insufficient evidence of medical necessity. It calls for periodic monitoring, a fixed period of validity and renewal when that period expires.

The design of the order form matters before any specimen arrives. Model Plan Helps Laboratories Fight Fraud, published in Laboratory Medicine in 1997, describes requisition forms that leave room for the necessity of each test. It also describes physician acknowledgment of customized profiles and monitoring standing orders for continued validity. These are controls over what the laboratory will run when someone selects a profile.

A profile name can conceal the individual procedures inside it. The useful comparison is the physician’s selection against the tests that selection actually generates, including additions made to the profile later.

Dianon and the Same Workup on Every Sample

Dianon Systems’ $1.5 million settlement in fiscal year 2008 addressed allegations that it ran 26 flow cytometry tests on every sample. The same full workup, every time, according to the allegations. The patient’s need should explain the extent of testing.

A separate Dianon settlement in fiscal year 2003 concerned allegations of second-opinion consultations that were not performed and unnecessary DNA analysis of urine cytology. Those are different failures in the same chain. One asks why testing was needed. The other asks whether the billed service happened at all.

For a consultation claim, we examine the request and the consultation actually produced. For an expanded flow workup, we examine the clinical support for the procedures performed. A result sheet, a consultation and a claim describe different parts of the service. Comparing them makes the missing part visible.

When the Order Form Has Already Chosen

A whistleblower complaint against Health Diagnostic Laboratory alleged that its cardiovascular panels included duplicative lipid tests and prevented physicians from removing one of them:

The allegation puts the choice inside the form itself. In a FISH or flow-cytometry inquiry, that is a useful comparison: what did the ordering practitioner select, and which procedures had the laboratory already bundled into that selection?

Flow Cytometry Billing Must Match the Work

More markers can add technical charges to a flow-cytometry claim. They do not turn one specimen into several separately billable interpretations. CGS Administrators’ flow-cytometry billing article for Kentucky and Ohio, revised March 5, 2026, makes that distinction concrete.

For flow immunophenotyping, the first marker’s technical work is billed under 88184, with each additional marker under 88185. That is where a routine expanded panel can add charges. The interpretation codes, 88187 through 88189, follow a different rule: only one interpretation code for all flow cytometry performed on a specimen.

Repeated testing across specimens also needs a clinical reason. The article requires morphology or other clinical factors suggesting different results before billing multiple specimens tested on the same day. And adding a flow-interpretation charge to the listed quantitative cell counts bills for an interpretive service the article says those counts do not have.

The patient’s history, the ordering provider’s assessment and pertinent test results should explain the workup. We compare that clinical support with the markers, specimens and interpretations on the claim. A diagnosis code carries the patient’s condition onto the bill. It cannot supply the missing reason for the testing.

Bostwick and FISH Tests the Treating Physician Had Not Ordered

The Justice Department’s 2016 announcement of the former owner’s separate settlement recounts Bostwick Laboratories’ August 2014 agreement to pay more than $6.5 million over allegations of unnecessary testing. The announcement alleged that the owner directed the laboratory to bill Medicare and Medicaid for unnecessary FISH and other tests performed without the treating physicians’ consent or order.

The same announcement describes alleged discounts and billing arrangements offered to induce referrals. That puts both ends of the transaction in view: how the specimen reached the laboratory and who authorized the additional testing after it arrived.

For someone inside the practice, the question is what the physician requested. For someone inside the laboratory, it is what the laboratory added. Comparing those accounts can show where the order stopped and the additional work began. The Bostwick allegations make that gap concrete.

21st Century Oncology and the Bonus for More FISH Tests

21st Century Oncology agreed to a $19.75 million settlement in December 2015 over alleged unnecessary FISH testing billed to Medicare and TRICARE. The Justice Department’s announcement alleged that four urologists ordered the tests and that the company encouraged unnecessary testing through bonuses based partly on the number referred to its laboratory.

The clinical question was specific. In a February 2017 settlement announcement involving one of those urologists, the Justice Department described Medicare’s standard for the urine FISH testing at issue: monitoring recurrence in a patient previously diagnosed with bladder cancer, or suspected bladder cancer after a full urologic workup in a patient with blood in the urine.

That announcement said the urologist ordered more than 13,000 separate FISH tests for Medicare patients and received approximately $2 million in bonuses associated with the tests. The company owned the laboratory receiving the referrals. The test needed a patient-specific reason. The bonus rewarded volume.

This comparison adds something to the routine-panel problem. The government alleged that physicians ordered unnecessary tests under an arrangement that rewarded referrals. The order, the clinical support and the compensation formula all belong in the inquiry. A completed requisition shows who requested the test. The patient’s chart and the bonus records help explain why.

The corporate case began with a former medical assistant’s whistleblower suit. The Justice Department announced a $3.2 million share of the recovery for that whistleblower. Someone working inside the practice could bring a case about the tests the practice sent to its own company’s laboratory.

How to Detect and Deter Laboratory Fraud?

Laboratory healthcare fraud can show up in the gap between what the practitioner requested and what the laboratory billed. Controls over requisitions, customized profiles and standing orders address the decision before it becomes another bill. We trace that decision through the practice and the laboratory with the insider who knows how the work gets added.

The payment arrangement can supply another part of the explanation. A referral bonus, a discount or a change to a profile can connect a recurring testing pattern to a business decision. We examine who chose the additional work and who benefited when it became routine.

Medicare’s documentation rule makes that connection consequential. When the ordering practitioner fails to supply requested medical-necessity records, Medicare can deny the laboratory’s claim. The clinical support may sit in the practice even though the laboratory is the business seeking payment.

A whistleblower case under the False Claims Act can pay 15% to 30% of what the government recovers.

You Know How the Extra Tests Get Added

If you see FISH or flow workups expanding beyond the patient’s need, speak with our whistleblower experts about who adds the tests and who gets paid. We work beside you to build the case from the ordering decisions, laboratory work and claims, and bring in laboratory fraud whistleblower lawyers who understand pathology testing and referral incentives. We stay with you through the case.