Test Code DICET DICER1 Mutation Analysis, Next-Generation Sequencing, Tumor
Ordering Guidance
Multiple oncology (cancer) gene panels are available. For more information see Hematology, Oncology, and Hereditary Test Selection Guide.
Necessary Information
A pathology report (final or preliminary), at minimum containing the following information, must accompany specimen 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 Required
This assay requires at least 20% tumor nuclei.
-Preferred amount of tumor area with sufficient percent tumor nuclei: tissue 216 mm(2)
-Minimum amount of tumor area: tissue 36 mm(2)
-These amounts are cumulative over up to 10 unstained slides and must have adequate percent tumor nuclei.
-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 10 unstained
Collection Instructions: Submit 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.
Additional Information: Unused unstained slides will not be returned.
Specimen Type: Cytology slide (direct smears or ThinPrep)
Slides: 1 to 3 Slides
Collection Instructions: Submit 1 to 3 slides stained and coverslipped with a preferred total of 5000 nucleated cells, or a minimum of at least 3000 nucleated cells.
Note: Glass coverslips are preferred; plastic coverslips are acceptable but will result in longer turnaround times.
Additional Information: Cytology slides will not be returned.
Useful For
Identifying specific mutations within the DICER1 gene to assist in tumor diagnosis/classification
Special Instructions
Method Name
Sequence Capture Next-Generation Sequencing (NGS)
Reporting Name
DICER1 Mutation Analysis, TumorSpecimen Type
VariesSpecimen Minimum Volume
See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Reject Due To
Specimens that have been decalcified (all methods) Specimens that have not been formalin-fixed, paraffin-embedded, except for cytology slides Extracted nucleic acid (DNA/RNA) |
Reject |
Clinical Information
This test uses formalin-fixed paraffin-embedded tissue or cytology slides to assess for somatic mutations involving the DICER1 gene known to be associated with multiple tumor types. DICER1 mutations are a diagnostic marker of embryonal rhabdomyosarcoma and Sertoli-Leydig cell tumors.(1) In central nervous system (CNS) tumors, DICER1 mutations are a diagnostic molecular biomarker for primary intracranial sarcoma, DICER1-mutant, embryonal tumor with multilayered rosettes and pituitary blastoma.(2) DICER1 mutations also occur in a subset of pineoblastoma, typically in the context of DICER1 tumor-predisposition syndrome. DICER1 tumor-predisposition syndrome is an inherited predisposition to pleuropulmonary blastoma, cystic nephroma, Wilms' Tumor, anaplastic sarcoma of the kidney, ovarian Sertoli-Leydig cell tumor, and cervical embryonal rhabdomyosarcoma.
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
12 to 20 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
88381-Microdissection, manual
81479
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.