Days Set Up
Monday – Thursday
Analytic Time

5-12 days

MiChart Code
RET Mutation in Malignancy
Soft Order Code

Test Updated:


Looking to order a test?

We’ve provided helpful links to make ordering easy.

Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

Visit our provider FAQ and learn about common questions to ordering tests.

Test Overview

Test Methodology

Next-Generation Sequencing

Test Usage

RET encodes a receptor tyrosine kinase involved neural crest development. Oncogenic RET mutations occur frequently in medullary thyroid carcinoma (MTC). Approximately 50-60% of sporadic MTC harbor somatic RET mutations. The presence of these mutations is associated with an inferior prognosis and more aggressive disease. Germline RET mutations are associated with multiple endocrine neoplasia (MEN) 2 or familial medullary thyroid carcinoma. Multi-kinase inhibitors (MKI) including vandetanib and cabozantinib are FDA-approved for the treatment of metastatic or unresectable MTC (regardless of RET mutation status). Reported response rates to these agents range from 20%-45%. These drugs are often associated with toxicities – some (e.g. impaired wound healing, fistula formation, hemorrhage) related to inhibition of other tyrosine kinases, particularly vascular endothelial growth factor receptor 2 (VEGFR-2). Several selective tyrosine kinase inhibitors (TKI) with much greater RET inhibitory potency have been developed including LOXO-292, BLU-667 and RXDX-105. These drugs have shown promising efficacy with significantly lower toxicity in RET-mutated MTC.

Reference Range

Interpretive report provided.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Offsite

For formalin-fixed, paraffin-embedded tissue, a block containing an area with a high percentage of neoplastic cells (for micro-/macro-dissection) is preferred. Unstained, UNBAKED slides (5-8, 10-micron slides; 10-15 if few neoplastic cells are present) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted and the assay attempted, however these may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature. A Diff-Quik or Papanicolaou stained aspirate smear (preferable containing a high percentage and overall amount of neoplastic cells) is also acceptable. Store at room temperature.

Normal Volume
Formalin-fixed, paraffin-embedded tissue; Diff-Quik stained aspirate smear, Papanicolaou stained aspirate smear.Extracted DNA is also acceptable if extracted in a CLIA certified laboratory.
Minimum Volume

Billing Information

CPT Code
81404, 88381-TC
Pro Fee Code

Have More Questions?

Explore our helpful billing resources:

Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.