CurrentAetnaPolicy 0686

Oral and Esophageal Brush Biopsy

Defines Aetna's coverage stance for oral and esophageal brush biopsy techniques (including OralCDx, WATS3D/EndoCDx, DNA/RNA-based tests and esophageal balloon sampling) for screening, diagnosis, and surveillance of oral and esophageal lesions; affects providers submitting claims to Aetna.

Policy Summary

PayerAetna

PolicyOral and Esophageal Brush Biopsy

Policy CodePolicy 0686

Change TypeNo material change

Effective DateMay 14, 2004

Next Review DateJul 25, 2024

Key ActionObtain confirmatory scalpel (tissue) biopsy for any suspicious or equivocal findings from brush cytology before making definitive management decisions.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

5procedures considered experimental/investigational

83%increase in BE detection (Gross et al.)

242%increase in ED detection (Smith et al.)

36studies in 2018 systematic review

09/15/2023last review

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Coverage Criteria

Experimental and Investigational

Aetna considers the following procedures experimental and investigational because effectiveness has not been established:

Experimental/Investigational list: 1) Oral brush biopsy (OralCDx Brush Test), with or without MAGE-A or GLUT-1 staining; 2) Esophageal brush biopsy (WATS3D/EndoCDx); 3) DNA-image cytometry of brush biopsies; 4) RNA-based oral brush biopsy; 5) Use of esophageal balloon for circumferential cytologic sampling.

These procedures are considered experimental/investigational and not established for screening, diagnosis or surveillance of cancerous or pre-cancerous lesions.

General coverage criteria

Coverage stance based on available evidence:

Adjunctive/Screening Use: Brush cytology and other adjunctive technologies may be used as screening or adjunctive tests to conventional oral examination but are not replacements for scalpel biopsy and histopathology.

Supported by systematic reviews and guideline statements noting limited high-quality evidence and that adjunctive tests cannot replace tissue diagnosis.

When to obtain scalpel biopsy: Findings deemed suspicious or equivocal on conventional exam or adjunctive testing should be referred to a specialist or undergo immediate scalpel biopsy for definitive diagnosis.

Brush 'biopsy' sampling cannot provide a definitive histologic diagnosis and positive/abnormal adjunctive results require confirmatory tissue biopsy.

Evidence summaries relevant to coverage

Summary of coverage-relevant evidence and contexts

Oral brush cytology evidence: Oral liquid-based brush cytology (OLBC) and other oral brush techniques have demonstrated variable diagnostic accuracy across studies; meta-analyses report moderate-to-high pooled sensitivity and specificity but study quality is limited and none of these methods replace scalpel biopsy for definitive diagnosis.

Evidence includes systematic reviews and cohort studies with methodological limitations (small samples, retrospective designs).

Esophageal WATS3D adjunct evidence: WATS3D added to standard forceps biopsy increases diagnostic yield for Barrett's esophagus and esophageal dysplasia in multiple studies (examples: Johanson 2011, Vennalaganti randomized trial showing additional HGD/EAC cases), but whether the increased diagnostic yield improves clinical outcomes is unclear and generalizability to non‑referral settings is uncertain.

Guideline statements emphasize diagnostic-yield data and rate the evidence as low quality for outcome benefit.

Adjunctive use supported with limitations

Evidence and guideline-supported scenarios from the provided text

Adjunctive use evidence: Multiple large observational and randomized studies report that adding WATS-3D to targeted and/or random forceps biopsy increases detection of Barrett's esophagus and esophageal dysplasia compared with forceps biopsy alone.

Adjunctive increases in detection reported in community and referral series but clinical significance and long‑term outcomes remain uncertain.

Limitations and validation concerns: Studies have limitations including referral-center enrichment, variability in pathology review (central lab vs local pathologists), potential false-positives, manufacturer involvement, and limited follow-up confirmation of WATS-only diagnoses.

These limitations support a cautious or conditional stance for adjunctive use.

Guideline recommendation: ASGE conditionally recommends using WATS-3D in addition to white-light endoscopy with Seattle protocol biopsies in patients with known or suspected Barrett's esophagus; the recommendation is conditional and evidence quality is rated low.

Supports adjunctive use but indicates uncertainty about effect on patient outcomes.

Adjunctive use with forceps biopsy

Evidence supports use of WATS-3D as an adjunct to white light endoscopy with Seattle protocol forceps biopsy in selected populations, with variable strength depending on dysplasia prevalence.

Adjunctive WATS-3D Covered When: WATS-3D used in addition to white light endoscopy with Seattle protocol 4‑quadrant forceps biopsies in patients with known or suspected Barrett's esophagus may increase dysplasia detection; benefit is greater in populations with higher baseline dysplasia prevalence.dependent on population dysplasia prevalence

ASGE gives a conditional recommendation based on low-quality evidence; adjunctive use increases detection but downstream outcome benefit is unproven.

Substitution or standalone use

Evidence for WATS-3D as a substitute for forceps biopsy or as standalone testing is limited and inconsistent.

Standalone WATS-3D Not Established: Randomized and cohort data show mixed results when WATS-3D is used as a single modality; some trials found no difference versus forceps biopsy, while others found increased detection in select subgroups. Clinical outcomes and the longitudinal significance of WATS-only dysplasia remain uncertain, so routine substitution is not established.insufficient evidence

Further prospective studies are needed before recommending routine standalone use.

Evidence-summary coverage considerations

Summary of evidence-based coverage implications from reviewed studies:

WATS-3D adjunctive use: Adding WATS-3D to Seattle protocol forceps biopsies increases dysplasia detection (meta-analyses report pooled RR ~1.7 for all dysplasia and higher absolute increases in high-prevalence populations); adjunctive benefit is greater where dysplasia prevalence is higher.

Clinical significance and management impact of additional detections require further study and confirmation.

WATS-3D as standalone: Randomized data did not show consistent superiority of WATS-3D alone over forceps biopsy for HGD/EAC detection in enriched populations; therefore WATS-3D alone should not routinely replace Seattle protocol forceps biopsies.

Combination of methods increases procedure time versus single modality.

DNA-image cytometry and OralCDx: Meta-analyses indicate DNA-image cytometry may have higher pooled specificity and similar sensitivity compared with OralCDx brush biopsy for oral lesions, but sampling limitations persist and these methods remain adjunctive rather than definitive diagnostic tests.

Positive adjunctive results in clinically suspicious lesions require confirmatory scalpel biopsy.

Aetna considers several brush-based and related transepithelial sampling techniques experimental and investigational because their effectiveness for screening, diagnosis, or surveillance of oral or esophageal cancer has not been established. These include Oral brush biopsy (OralCDx Brush Test) (with or without MAGE‑A or GLUT‑1 staining), esophageal brush biopsy (WATS‑3D/EndoCDx), DNA‑image cytometry of brush specimens, RNA‑based oral brush biopsy, and use of an esophageal balloon for circumferential cytologic sampling. These procedures are considered not established for routine clinical use for screening, diagnosis, or surveillance of cancerous or pre‑cancerous lesions.

Brush cytology techniques (oral or esophageal) cannot provide a definitive histologic diagnosis because they sample cells rather than intact tissue; therefore a positive or suspicious brush result must be confirmed with a scalpel (tissue) biopsy and histopathology before establishing a diagnosis or directing definitive therapy.

Major society guidelines (including the American Gastroenterological Association, the American College of Gastroenterology, the British Society of Gastroenterology, and Cancer Council Australia) do not recommend brush biopsy for Barrett’s esophagus screening or routine surveillance. Guideline statements emphasize that brush biopsy techniques have not been established as standard screening or surveillance tools for Barrett’s esophagus.

Available evidence does not establish that WATS‑3D can reliably substitute for the Seattle protocol 4‑quadrant random forceps biopsy. Randomized and cohort studies were generally designed to evaluate WATS‑3D as an adjunctive technique or compared modalities without demonstrating consistent superiority of WATS‑3D as a standalone replacement for standard sampling.

Although WATS‑3D increases the number of dysplasia diagnoses in many series, the clinical significance of additional detections (for example, dysplasia found only by WATS, crypt dysplasia, or cases reported as indefinite for dysplasia) is uncertain. Studies have limited long‑term outcome data and variable pathologic confirmation, so the impact of these additional findings on patient outcomes is not well defined.

The policy excerpts do not list explicit payer exclusions beyond designation of the listed procedures as experimental/investigational, but note important limitations—such as lack of centralized pathology concordance, limited long‑term follow‑up, variable dysplasia definitions, and potential industry sponsorship—that argue for cautious interpretation before covering WATS‑3D or related brush techniques as standalone replacements for standard care.

This Clinical Policy Bulletin is intended as informational guidance to assist in administering plan benefits. It is a partial description of benefits and does not constitute a contract; specific plan documents and coverage determinations govern actual coverage decisions.

There is insufficient evidence to support use of oral brush biopsy as a routine general screening test for oral cancer or potentially premalignant oral lesions. Systematic reviews and guideline statements conclude that brush cytology is an adjunctive screening tool at best, and positive or suspicious results require confirmatory scalpel biopsy.

Routine population‑based screening using adjunctive technologies (including brush biopsy, toluidine blue, or fluorescence imaging) is not supported by robust randomized trial evidence to demonstrate a reduction in oral cancer mortality, except for limited findings in select high‑risk subgroups; therefore routine population screening with these adjuncts is not supported.

Randomized and comparative data do not support routine replacement of the Seattle protocol forceps biopsy with WATS‑3D. Where studied, WATS‑3D has generally been evaluated as an adjunct to white‑light endoscopy with Seattle protocol biopsies rather than as a proven standalone alternative.

Using WATS‑3D as the sole surveillance technique without confirmation by forceps biopsy has not been established. Studies that report WATS‑only dysplasia often lack routine confirmatory histology and have limited follow‑up, so the diagnostic validity and longitudinal implications of WATS‑only findings remain unproven.

WATS‑3D results alone should not routinely be used to direct definitive management in place of confirmatory forceps biopsy histology. Randomized data from enriched cohorts did not show WATS‑3D alone to be superior to forceps biopsy for detection of high‑grade dysplasia or esophageal adenocarcinoma, so forceps biopsy and histology remain the primary basis for management decisions.

Randomized data in enriched Barrett’s esophagus populations did not demonstrate that WATS‑3D alone is superior to forceps biopsy for detecting high‑grade dysplasia or esophageal adenocarcinoma. Given those findings, forceps biopsy using the Seattle protocol is considered the primary sampling method, with WATS‑3D considered adjunctive rather than a routine replacement.

Coding

Other CPT codes related to the policyCPT

88104	Cytopathology, fluids, washings or brushings, except cervical or vaginal; smears with interpretation.
99000	Handling and/or conveyance of specimen for transfer from the physician's office to a laboratory.
40808	Biopsy, vestibule of mouth.
41108	Biopsy of floor of mouth.
42800	Biopsy; oropharynx.
42804	nasopharynx, visible lesion, simple.
42806	nasopharynx, survey for unknown primary lesion.
43191	Esophagoscopy, rigid, transoral; diagnostic, including collection of specimen(s) by brushing or washing when performed (separate procedure).
43200	Esophagoscopy, flexible, transoral; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure).
88160	Cytopathology smears, any other source; screening and interpretation.

HCPCS codes referencedHCPCS

D0486	Laboratory accession of transepithelial cytologic sample, microscopic examination, preparation and transmission of written report.
D7288	Brush biopsy - transepithelial sample collection.
D7287	Exfoliative cytological sample collection.

ICD-10 codes referenced (examples/not-covered contexts)ICD-10

D00.00 - D00.08	Carcinoma in situ of lip, oral cavity, and pharynx.
D10.0 - D11.9	Benign neoplasm of mouth, pharynx and major salivary glands.
D37.01 - D37.02, D37.04 - D37.09	Neoplasm of uncertain behavior of lip, oral cavity, and pharynx.
K09.1 - K09.9	Cysts of oral region, not elsewhere classified.
K12.0 - K13.79	Stomatitis and related lesions and other diseases of lip and oral mucosa.
K14.0 - K14.9	Diseases of tongue.
Z12.81	Encounter for screening for malignant neoplasm of oral cavity.

Coding guidance (no codes specified)mixed

not provided

No explicit CPT/ICD codes listed in this document fragment.

Esophageal brush biopsy (WATS3D) - affected codesmixed

affected codes

WATS3D / brush biopsy procedure codes referenced as affected by policy (document lists 'affected codes' placeholder)

Procedure codes (not listed)mixed

not specified

The provided document excerpt does not list CPT/HCPCS/ICD codes for WATS-3D or brush biopsy.

References only — no explicit codes provided in this sectionmixed

No codes listed

Provider Actions & Billing Notes

Billing Rule

Coding reference and billing notes

Providers should reference the code groups below when submitting authorization requests or claims. Codes specific to oral or esophageal brush cytology that are listed as experimental/investigational should be submitted with appropriate clinical justification; claims relying solely on brush cytology without confirmatory tissue biopsy may be challenged or denied.

CPT/HCPCS/ICD-10 coding reference (see code table for detailed lists).
Claims based only on brush biopsy cytology (no scalpel/forceps tissue biopsy) lack histologic confirmation and may be denied.
When brush methods are billed adjunctively to standard biopsies, include both sets of results in the record.

Prior Authorization

Prior Authorization — adjunctive and substitution use

Background

Scalpel (tissue) biopsy is the definitive diagnostic method for oral mucosal lesions. Brush biopsy techniques were developed as less invasive adjunctive methods to sample epithelial layers, but they detect cellular atypia rather than provide histologic architecture; therefore positive brush results require confirmation with scalpel biopsy and histopathology for a definitive diagnosis.

Definitions

Oral brush biopsy (OralCDx) — transepithelial sample obtained with circular bristled brush

DefinitionA transepithelial sample obtained with a specially designed circular bristled brush intended to collect cells from all epithelial layers (including basal layer) for cytologic analysis.

Intended useAdjunctive screening/assessment of clinically detectable oral mucosal lesions to help identify lesions that may require scalpel biopsy for definitive diagnosis.

Diagnostic limitationBrush cytology cannot provide a definitive histologic diagnosis; tissue (scalpel) biopsy is required to confirm malignancy.

Esophageal brush biopsy (WATS3D/EndoCDx) — esophageal brush biopsy technique for cytologic analysis

DefinitionAn esophageal brush biopsy technique (WATS3D/EndoCDx) that samples esophageal mucosa for computer-assisted cytologic analysis using a wide-area transepithelial abrasive brush, processed with proprietary 3-D analysis.

Revision History

Policy Summary

PayerAetna

PolicyOral and Esophageal Brush Biopsy

Policy CodePolicy 0686

Change TypeNo material change

Effective DateMay 14, 2004

Next Review DateJul 25, 2024

Key ActionObtain confirmatory scalpel (tissue) biopsy for any suspicious or equivocal findings from brush cytology before making definitive management decisions.

SourceLink

On This Page

Esophageal balloon sampling: Preclinical testing suggests circumferential esophageal balloon sampling may capture comparable cellularity to quadrant brushes, but clinical outcome data are limited and not sufficient to support clinical use.

Evidence level is low; further clinical studies required.

Prior authorization (PA) may be required when adding WATS-3D (esophageal brush biopsy) to standard forceps biopsy, or when proposing WATS-3D as a replacement for forceps biopsy (FB). When requesting PA, clearly state whether WATS-3D is being used as an adjunct to FB or proposed as a substitution, and provide rationale and relevant clinical history (e.g., prior dysplasia, prior non-diagnostic FB, extent of Barrett’s segment).

PA more likely when WATS-3D is proposed instead of the Seattle protocol FB.
If PA is requested for adjunctive WATS-3D use, document why adjunctive sampling is necessary (e.g., prior negative FB with persistent clinical suspicion).

Documentation Required

Clinical documentation and follow-up

Document the intended role of any brush-based test in the clinical encounter: whether it is an adjunct to forceps biopsy, a screening tool, or proposed as a replacement. Include the conventional oral exam or white-light endoscopic assessment findings, rationale for adjunctive testing, and how the brush result informed management.

Record conventional oral examination (COE) or white light endoscopy (WLE) findings and any focal/suspicious lesion descriptions prior to adjunctive testing.
For adjunctive WATS-3D, document whether the Seattle protocol or targeted biopsies were performed and the order of procedures (WATS vs FB).
When brush testing is adjunctive, include both brush cytology results and corresponding FB histology in the chart.
If brush cytology is positive, document plans for confirmatory scalpel/forceps biopsy (definitive diagnostic step).

Documentation Required

Adjunctive use documentation recommended

Adjunctive testing should be accompanied by specific documentation to support its use and to permit accurate adjudication: indication for adjunctive testing, prior biopsy history, presence or absence of focal lesions, adherence to Seattle protocol (for BE), and the impact of adjunctive results on clinical management.

When WATS-3D is used adjunctively, document how the additional findings changed surveillance intervals or triggered therapy.
Specify whether targeted biopsies of suspicious areas were obtained and placed in separate pathology containers.
Include correspondence or records of any downstream management decisions (surveillance enrollment, increased surveillance frequency, initiation of ablation, PPI changes) prompted by WATS findings.

Documentation Required

Specimen handling and pathology review

Specimen handling and pathology review differ between modalities and should be documented. WATS-3D specimens are generally analyzed centrally (CDx laboratory) while forceps biopsy specimens are reviewed by institutional pathologists; when discrepant results occur, note any secondary/central pathology review and reconciliation steps.

Ship WATS-3D specimens per manufacturer's/central lab instructions and document chain of custody/handling.
Document whether forceps biopsy slides underwent local and/or central expert re-review, especially when WATS and FB results disagree.
If pathology discrepancy exceeds local thresholds (e.g., >10% discordance in some studies), document whether central confirmation was sought.

Documentation Required

Document concurrent FB and WATS-3D results and resultant management

Document concurrent FB and WATS-3D results and the resultant management decisions. Records should show how discordant results were reconciled and whether positive brush findings prompted confirmatory tissue biopsy or changes in surveillance/therapy.

When FB is negative but WATS-3D is positive, document subsequent confirmatory steps taken (repeat FB, targeted biopsy, expert pathology review).
Capture management actions resulting from WATS-3D findings (e.g., enrollment in surveillance, initiation/increase of PPI therapy, referral for ablation).

Note

Evidence and outcome considerations

Recognize and document limitations of the evidence. Increased diagnostic yield with WATS-3D has been demonstrated in multiple studies, but whether this translates to improved patient outcomes remains uncertain; evidence quality has been rated low to inconsistent in guidelines.

Note in the medical record when WATS-3D is being used despite limited evidence for outcome benefit.
When relying on registry or single-center data to support use, document study limitations and applicability to the patient’s setting.

Denial Risk

Experimental/Investigational exclusions

Brush-based tests listed as experimental/investigational per this policy should be recognized as such in requests and claims. Procedures considered experimental/investigational may be excluded from coverage.

OralCDx brush test and other RNA/DNA-based brush assays are listed as experimental/investigational.
Esophageal brush biopsy (WATS3D/EndoCDx) is listed in the Experimental/Investigational section for certain indications — check policy specifics.
Use of esophageal balloon sampling for circumferential cytology is considered experimental/investigational.

Step Therapy

Confirmatory diagnostic step required

A tissue biopsy (scalpel or forceps biopsy) remains the diagnostic standard. Positive brush cytology results should prompt confirmatory tissue biopsy because cytology alone cannot provide histologic diagnosis required for definitive management.

Claims or prior authorization requests relying solely on brush cytology without confirmatory tissue biopsy should include medical justification; absence of histologic confirmation may lead to denial.
When a brush test is positive for dysplasia or malignancy, document the plan and timing for confirmatory forceps/scalpel biopsy.

Step Therapy

Preferred evaluation sequence; adjunct before replacement

Providers should follow a preferred evaluation sequence: perform a conventional oral exam or white-light endoscopic assessment first, obtain targeted forceps biopsies of suspicious lesions (Seattle protocol/random 4-quadrant FB for BE) as the initial diagnostic sampling, and reserve brush cytology or WATS-3D for adjunctive use when indicated. WATS-3D was primarily studied as an adjunct, not a replacement, so stepwise use (FB first, adjunctive WATS as needed) is recommended.

Adjunctive testing is appropriate when FB is non-diagnostic or when there is persistent clinical concern despite negative FBs.
Do not use WATS-3D routinely as a substitute for FB without prior authorization and strong clinical justification.

Documentation Required

Documentation completeness and protocol adherence

Lack of adherence to standard biopsy protocols (e.g., Seattle protocol) or incomplete documentation of indications and focal lesions can bias comparisons between FB and WATS-3D and may affect coverage decisions. Ensure documentation of adherence to biopsy protocols and completeness of clinical data.

Document whether the Seattle protocol or appropriate 4-quadrant sampling was performed and any deviations from protocol.
If data are incomplete (e.g., missing indication, segment length, prior dysplasia history), state this in requests and provide available supplementary records.

Note

Policy scope and provider responsibilities

Clinical Policy Bulletins are informational and provide a partial description of benefits; they do not constitute a contract. Providers remain responsible for clinical decisions and for obtaining benefit verification and any required prior authorization.

Confirm member-specific coverage and PA requirements with the payer prior to performing procedures.
This CPB does not replace plan documents — use plan benefits and authorizations to determine coverage.

Intended roleUsed as an adjunct to standard forceps biopsy during endoscopic evaluation of Barrett's esophagus to increase the sampled tissue area and diagnostic yield.

Evidence contextEvidence is diagnostic-yield focused; whether increased yield improves patient outcomes is unclear.

Brush biopsy / oral cytology — exfoliative transepithelial sampling technique intended as screening/adjunctive test

DefinitionExfoliative transepithelial sampling technique using a brush to harvest cells from oral surface lesions; intended as a screening or adjunctive test rather than a replacement for tissue biopsy.

Analytic methodsMay be analyzed by conventional cytology or liquid-based cytology with computer-assisted interpretation depending on the assay.

Clinical noteAppropriate as a preliminary tool to help confirm clinical suspicion, but positive or suspicious results require referral or scalpel biopsy for definitive diagnosis.

Liquid-based cytology (LBC) — technique preparing exfoliative cytology samples (e.g., Orcellex)

DefinitionA laboratory preparation technique for exfoliative cytology specimens (liquid-based cytology, LBC) that can improve specimen adequacy and cell morphology (example device: Orcellex).

Clinical advantageLBC preparations have shown improved slide quality and low rates of inadequate specimens compared with some spatula methods in preliminary studies.

RoleUsed to prepare brush-obtained oral cytology samples for microscopic evaluation and potential ancillary testing (e.g., immunocytochemistry).

WATS3D — wide-area transepithelial sampling with 3-D analysis (term reference)

DefinitionWide-area transepithelial sampling with 3-dimensional analysis (WATS3D): an abrasive brush-based sampling method combined with computer-assisted 3-D cytologic analysis to increase the area and depth of esophageal mucosal sampling.

Intended useDesigned as an adjunct to forceps biopsies during endoscopic surveillance of Barrett's esophagus to increase dysplasia detection rates.

Interpretation noteSpecimens are processed with proprietary algorithms and interpreted by specialized pathology services (manufacturer-associated labs in many studies).

OLBC — oral liquid-based brush cytology collection method

DefinitionOral liquid-based brush cytology (OLBC): minimally invasive collection of transepithelial oral mucosal samples using specialized brushes with specimens prepared by liquid-based cytology methods.

Clinical findingsOLBC has demonstrated promising sensitivity and specificity in small studies and may be coupled with immunocytochemistry for risk stratification of oral leukoplakia.

LimitationFurther research and standardization of reporting (modified Bethesda-like systems) are recommended before widespread adoption as standalone diagnostic test.

Crypt dysplasia — cytologic finding on WATS with uncertain natural history

DefinitionA cytologic finding on WATS specimens characterized by dysplasia confined to crypts (crypt dysplasia, CD), distinct from surface epithelial dysplasia.

Clinical uncertaintyNatural history and prognostic significance of crypt dysplasia are not fully defined; reported progression rates in cohorts have varied and require further study.

Evidence noteOne analysis reported progression of crypt dysplasia to high-grade dysplasia/esophageal adenocarcinoma at approximately 1.42% per patient-year in a WATS cohort.

Seattle protocol — standard 4-quadrant random forceps biopsy sampling protocol for Barrett's surveillance

DefinitionStandard 4-quadrant random forceps biopsy sampling protocol (Seattle protocol) used during endoscopic surveillance of Barrett's esophagus.

Clinical roleConsidered the baseline histologic sampling standard to which adjunctive techniques (e.g., WATS-3D) are compared; many studies evaluate WATS as an adjunct to the Seattle protocol.

DocumentationWhen WATS-3D is used adjunctively, documentation should indicate that Seattle protocol biopsies were performed and record segment length and focal lesions.

WATS-3D — abrasive brush sampling processed with proprietary algorithm (definition)

DefinitionWATS-3D: an abrasive wide-area transepithelial brush sampling method processed with a proprietary algorithm and computer-assisted 3-D analysis to identify abnormal cells.

ProcessingSamples are analyzed with specialized software/algorithms and reported by pathology services associated with the WATS-3D platform in published studies.

Comparative noteWATS-3D increases sampled area compared with standard cytology brushes and has been reported to increase dysplasia detection when added to forceps biopsy.

Barrett's esophagus (BE) — definition of BE (salmon-colored mucosa >1 cm with IM)

DefinitionBarrett's esophagus (BE): salmon-colored mucosa extending more than 1 cm proximal to the gastroesophageal junction with histologic evidence of intestinal metaplasia.

Clinical contextBE is a precursor lesion for esophageal adenocarcinoma; surveillance strategy typically involves high-definition white light endoscopy with Seattle protocol biopsies at regular intervals based on dysplasia status.

Risk noteThe annual incidence of progression from non-dysplastic BE to esophageal adenocarcinoma is low (~0.3% per year), guiding surveillance and management approaches.

WATS-3D — alternate reference (computer-assisted 3D analysis) — duplicate term entry present in inventory

Alternate termWATS-3D: wide-area transepithelial sampling with 3-dimensional computer-assisted analysis; used interchangeably with WATS3D/EndoCDx in literature.

Usage noteMost studies evaluate WATS-3D as an adjunct to forceps biopsy rather than as a standalone surveillance test; guideline recommendations are conditional and evidence quality is low.

TerminologyAlso referenced historically as EndoCDx in earlier publications and manufacturer materials.

DNA-image cytometry (DNA-ICM) — computer-assisted cytometric technique measuring nuclear DNA content on exfoliative samples

DefinitionDNA-image cytometry (DNA-ICM): a computer-assisted cytometric technique measuring nuclear DNA content (ploidy) on exfoliative brush samples to help detect malignant or pre-malignant oral lesions.

PerformanceMeta-analyses report pooled sensitivity around 89% and pooled specificity around 99% for DNA-ICM in detecting oral precancer/cancer, higher specificity than OralCDx in pooled studies.

Clinical roleMay offer improved diagnostic accuracy over some brush cytology methods, but sampling limitations and heterogeneity across studies limit its use as a standalone diagnostic replacement for histologic biopsy.