RET/PTC Rearrangement, Thyroid Cancer

Test Code

90473

CPT Codes
81479

Includes

RET/PTC1, RET/PTC3

Preferred Specimen

1 formalin-fixed, paraffin-embedded tissue block or needle washing

Instructions

⁠⁠⁠⁠⁠⁠⁠Do not reject. Needle washings in alcohol-based fixative (e.g. CytoLyt®) or formalin-fixed, paraffin-embedded tissue block FNA or FFPE specimens are acceptable for the assay.
All specimens must be accompanied with Pathology report. All FFPE specimens will be examined by a pathologist for confirmation and adequacy. Macrodissection if warranted is performed in the lab.

Transport Temperature

Room temperature

Specimen Stability

FNA or FFPE
Room temperature: 5 years
Refrigerated: 5 years
Frozen: Unacceptable

Needle washings
Room temperature: 30 days
Refrigerated: 30 days
Frozen: Unacceptable

Methodology
Real-Time Polymerase Chain Reaction (PCR)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Sets up 7 days a week.

Clinical Significance

RET/PTC gene fusion is detected in 5-40% of papillary thyroid carcinomas, but has been reported at low frequency in other types of thyroid lesions. Correlation with morphologic and clinical findings is thus required.
The assay tests for both RET/PTC1 and RET/PTC3 rearrangements using a reverse transcription PCR assay. The lower limit of sensitivity is approximately 2.5% mutation-bearing cells in a mixed sample, but can vary due to RNA preservation.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.