November 2025 WML Test Directory Update

Update to turnaround time

Turnaround Time: 12 – 14 days

Update to CPT code, stability, methodology, reference range, performed days, and turnaround time

CPT Code: 82397

Stability:

Room temperature: 48 hours
Refrigerated: 14 days
Frozen: 30 days (avoid repeated freeze/thaw cycles)

Methodology: Semi-quantitative Chemiluminescent Immunoassay (CLIA)

Reference Range: Less than 20.0

Performed Days: Monday, Wednesday, Friday

Turnaround Time: 3 – 7 days

Update to rejection criteria and stability

Rejection Criteria: Unpreserved stool; Specimens received >15 days from date of collection

Stability:

Room temperature: 15 days
Refrigerated: 15 days
Frozen: Unacceptable

Update to specimen requirements

Specimen Preparation: Send 5.0 mL of well-mixed body fluid in a sterile screw capped plastic vial. Indicate specimen source.

Update to specimen requirements, rejection criteria, stability, methodology, and reference range.

Specimen Preparation: Centrifuge, separate serum from cells within 2 hours, and send 0.5 mL serum in a screw capped plastic vial. Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens. Mark specimens plainly as “acute” or “convalescent”.

Minimum volume: 0.3 mL

Rejection Criteria: Bacterially contaminated, heat-inactivated, hemolyzed, icteric, lipemic, or turbid specimens.

Stability:

Room temperature: 48 hours
Refrigerated: 14 days
Frozen: 30 days (avoid repeated freeze/thaw cycles)

Methodology: Semi-quantitative Indirect Fluorescent Antibody (IFA)

Reference Range: Less than 1:10

Update to specimen requirements, alternate specimen, stability, and performed days

Patient Preparation: Pathology report must accompany specimen in order for testing to be performed. This assay requires at least 40% tumor nuclei for endometrial specimens and at least 20% tumor nuclei for colorectal specimens.

Collect: Tissue block

Specimen Preparation: Send a formalin-fixed paraffin embedded tissue block, (non-decalcified), with approximately 72 mm(2) area of tumor.

Minimum Volume: 18 mm(2) area of tumor

Alternate Specimen:

Tissue slide: 1 Slide stained with hematoxylin and eosin and 10 Unstained, nonbaked slides with 5-micron thick sections of the tumor tissue.
Note: The total amount of required tumor nuclei can be obtained by scraping up to 10 slides from the same block. Unused unstained slides will not be returned.

Stability:

Room temperature: Indefinitely
Refrigerated: Unacceptable
Frozen: Unacceptable

Performed Days: Varies

Update to CPT code and methodology

CPT Code: 82570

Methodology: Colorimetry