New gene panel enhances brain tumor profiles


Answers from the Lab

Molecular biomarkers were recently added to the World Health Organization's classification of brain tumors. In this test specific episode of the "Answers From the Lab" podcast, Cristiane (Cris) Ida, M.D., explains how Mayo Clinic Laboratories' updated neuro-oncology gene panel reflects those changes and yields more clinically relevant information for managing adult and pediatric brain tumors.

"We are now able to provide testing that is well-aligned with the new WHO classification," Dr. Ida says. "Our test has high clinical utility both for diagnostic and, in some instances, therapeutic purposes."

The carefully curated NONCP panel includes diagnostically relevant genes that weren't in the prior panel and omits genes that have been shown to lack strong clinical relevance. NONCP's DNA and RNA subpanels provide simultaneous evaluations for genetic mutations, microsatellite instability status, and gene fusions.

"It is a one-stop shop approach that is particularly useful for complex cases," Dr. Ida says. "The field is evolving quickly, with new biomarkers and molecular features being unraveled every day. This new panel is one of the best tests available for clinicians."

Listen to learn more about Mayo Clinic Laboratories' updated neuro-oncology panel.

Note: Podcasts will not playback on Internet Explorer. Please use an alternative web browser, or listen from your mobile device on a preferred listening app.

Testing

Useful information

  • Identifying mutations and rearrangements that may support a diagnosis for patients with tumors of the central nervous system (CNS).
  • Identifying mutations and rearrangements that may help determine prognosis for patients with tumors of the CNS.
  • Identifying specific mutations and rearrangements within genes known to be associated with response or resistance to specific cancer therapies.

Specimen requirements

Necessary information:

Pathology report (final or preliminary) at minimum containing the following information must accompany specimen in order for testing to be performed:

  1. Patient name.
  2. Block number-must be on all blocks, slides and paperwork (can be handwritten on the paperwork).
  3. Tissue collection date.
  4. Source of the tissue.

Specimen requirements:

This assay requires at least 20% tumor nuclei.

  • Preferred amount of tumor area with sufficient percent tumor nuclei: tissue 360 mm(2).
  • Minimum amount of tumor area: tissue 72 mm(2).
  • Tissue fixation: 10% neutral buffered formalin, not decalcified.

For specimen preparation guidance, see Tissue Requirement for Solid Tumor Next-Generation Sequencing. In this document, the sizes are given as 4 mm x 4 mm x 10 slides as preferred: approximate/equivalent to 144 mm(2) and the minimum as 3 mm x 1 mm x 10 slides: approximate/equivalent to 36 mm(2).

Preferred:

  • Specimen Type: Tissue block.
  • Collection Instructions: Submit a formalin-fixed, paraffin-embedded tissue block with acceptable amount of tumor tissue.

Acceptable:

  • Specimen Type: Tissue slide.
  • Slides: 1 stained and 15 unstained.
  • Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 15 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 15 slides from the same block.

Additional information: Unused unstained slides will not be returned.

Performance information

Analytic time: 12 to 20 days

Days performed: Monday through Friday

The latest

Barbara J. Toman

Barbara J. Toman is a Senior Communications Specialist at Mayo Clinic Laboratories. She is also the science writer for Mayo’s Neurosciences Update newsletter, which helps referring physicians to stay informed about Mayo’s treatment and research. Barbara has worked at Mayo Clinic since 2007. She enjoys international travel and cooking.