Identifying specific mutations within the ELOC (TCEB1), TSC1, TSC2, and VHL genes to assist in tumor diagnosis/classification
Assisting in the clinical management of patients with renal cell carcinoma
This test uses targeted next-generation sequencing to evaluate for somatic mutations within the ELOC (TCEB1), TSC1, TSC2, and VHL genes. See Targeted Genes and Methodology Details for MayoComplete Fibromyomatous Renal Cell Carcinoma for details regarding the targeted gene regions evaluated by this test.
This test is performed to evaluate for somatic mutations within solid tumor samples. This test does not assess for germline alterations within the genes listed.
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
SLIRV | Slide Review in MG | No, (Bill Only) | Yes |
When this test is ordered, slide review will always be performed at an additional charge.
Sequence Capture Next-Generation Sequencing (NGS)
RCC
Renal cell carcinoma
Renal cell carcinoma with fibromyomatous stroma
ELOC
TCEB1
TSC1
TSC2
VHL
Next Generation Sequencing Test
NGS
Oncology Panel
Tumor Panel
When this test is ordered, slide review will always be performed at an additional charge.
Varies
Multiple oncology (cancer) gene panels are available. For more information see Hematology, Oncology, and Hereditary Test Selection Guide.
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
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.
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.
See Specimen Required
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 |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Identifying specific mutations within the ELOC (TCEB1), TSC1, TSC2, and VHL genes to assist in tumor diagnosis/classification
Assisting in the clinical management of patients with renal cell carcinoma
This test uses targeted next-generation sequencing to evaluate for somatic mutations within the ELOC (TCEB1), TSC1, TSC2, and VHL genes. See Targeted Genes and Methodology Details for MayoComplete Fibromyomatous Renal Cell Carcinoma for details regarding the targeted gene regions evaluated by this test.
This test is performed to evaluate for somatic mutations within solid tumor samples. This test does not assess for germline alterations within the genes listed.
When this test is ordered, slide review will always be performed at an additional charge.
A subset of renal cell carcinoma commonly referred to as "renal cell carcinoma with fibromyomatous stroma" frequently shows overlapping morphologic and immunophenotypic features. These tumors are thought to arise secondary to alterations of ELOC (also referred to as TCEB1) and other MTOR (mechanistic target of rapamycin) pathway genes, such as TSC1 and TSC2. Furthermore, these tumors are unrelated to clear cell renal cell carcinoma that typically show alterations of the VHL gene (including epigenetic silencing, truncating alterations, and deletions). The 5th edition of the World Health Organization classification of tumors recognizes ELOC (TCEB1)-mutated renal cell carcinoma as a molecularly defined entity.(1) This assay, performed using formalin-fixed paraffin-embedded tissue or cytology material, is therefore helpful for establishing an accurate diagnosis and to define prognosis. It is important to note that this assay does not distinguish between germline and somatic alterations.
An interpretive report will be provided.
The interpretation of molecular biomarker analysis includes an overview of the results and the associated diagnostic, prognostic, and therapeutic implications.
This test cannot differentiate between somatic and germline alterations. Additional testing may be necessary to clarify the significance of results if there is a potential hereditary risk.
DNA variants of uncertain significance may be identified.
A negative result does not rule out the presence of a variant that may be present below the limits of detection of this assay. In a sample with 20% or more tumor content, the analytical sensitivity of this assay for sequence reportable alterations is 5% mutant allele frequency with a minimum coverage of 500X.
Point mutations and small deletion-insertion mutations will be detected in the ELOC (TCEB1), TSC1, TSC2, and VHL genes only. This test may detect single exon deletions but does not detect multi-exon deletions, duplications, or genomic copy number variants.
Variant allele frequency (VAF) is the percentage of sequencing reads supporting a specific variant divided by the total sequencing reads at that position. In somatic testing, VAF should be interpreted in the context of several factors, including, but not limited to, tumor purity/heterogeneity/copy number status (ploidy, gains/losses, loss of heterozygosity) and sequencing artifact/misalignment.(2,3)
Rare alterations (ie, polymorphisms) may be present that could lead to false-negative or false-positive results.
Test results should be interpreted in the context of clinical, tumor sampling, histopathological, and other laboratory data. If results obtained do not match other clinical or laboratory findings, contact the laboratory for discussion. Misinterpretation of results may occur if the information provided is inaccurate or incomplete.
Reliable results are dependent on adequate specimen collection and processing. This test has been validated on cytology slides and formalin-fixed, paraffin-embedded tissues; other types of fixatives are discouraged. Improper treatment of tissues, such as decalcification, may cause polymerase chain reaction failure.
Performance Characteristics
The limit of detection for calling a somatic variant (single nucleotide variants [SNV] and deletions/insertions [delins, formerly indel]) is 5% variant allele frequency (VAF) and having at least 500x deduplicated coverage.
Verification studies demonstrated concordance between this test and the reference method for detection of SNV and delins is 98.5% (673/683) and 98.4% (122/124) of variants, respectively. Concordance for the detection of delins was 99.0% (100/101) in variants 1 to 10 base pairs (bp) in size, 93.3% (14/15) in variants 11 to 50 bp in size, and 100% (8/8) in variants over 50 bp in size.
To ensure accuracy, this test will be performed on cases that are estimated by a pathologist to have at least 20% tumor cells.
1. WHO Classification of Tumours Editorial Board. Urinary and male genital tumors. 5th ed, World Health Organization; 2022. WHO Classification of Tumours. Vol 8
2. Strom SP. Current practices and guidelines for clinical next-generation sequencing oncology testing. Cancer Biol Med. 2016;13(1):3-11. doi:10.28092/j.issn.2095-3941.2016.0004
3. Spurr L, Li M, Alomran N, et al. Systematic pan-cancer analysis of somatic allele frequency. Sci Rep. 2018;8(1):7735. Published 2018 May 16. doi:10.1038/s41598-018-25462-0
4. Shah RB. Renal cell carcinoma with fibromyomatous stroma-The whole story. Adv Anat Pathol. 2022;29(3):168-177
5. Trpkov K, Williamson SR, Gill AJ, et al: Novel, emerging and provisional renal entities: The genitourinary pathology society (GUPS) update on renal neoplasia. Mod Pathol. 2021;34(6):1167-1184
6. DiNatale RG, Gorelick AN, Makarov V, et al: Putative drivers of aggressiveness in TCEB1-mutant renal cell carcinoma: An emerging entity with variable clinical course. Eur Urol Focus. 2021;7(2):381-389
7. Shah RB, Stohr BA, Tu ZJ, et al: "Renal Cell carcinoma with leiomyomatous stroma" Harbor somatic mutations of TSC1, TSC2, MTOR, and/or ELOC (TCEB1): clinicopathologic and molecular characterization of 18 sporadic tumors supports a distinct entity. Am J Surg Pathol. 2020;44(5):571-581.
8. Gupta S, Stanton ML, Reynolds JP, et al: Reprint of: lessons from histopathologic examination of nephrectomy specimens in patients with tuberous sclerosis complex: cysts, angiomyolipomas & renal cell carcinoma. Hum Pathol. 2023;133:136-152
Next-generation sequencing is performed to evaluate the presence of a mutation in most coding regions of the ELOC (TCEB1), TSC1, TSC2, and VHL genes. See Targeted Genes and Methodology Details for MayoComplete Fibromyomatous Renal Cell Carcinoma or details regarding the targeted gene regions identified by this test.(Unpublished Mayo method)
A pathology review and macro dissection to enrich for tumor cells is performed prior to slide scraping.
Monday through Friday
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.
88381-Microdissection, manual
81479
81406
81407
81404
81479 (if appropriate for government payers)
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
MCFRC | MayoComplete Fibromyomatous RCC | 105591-2 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
619614 | Result | 82939-0 |
619615 | Interpretation | 69047-9 |
619616 | Additional Information | 48767-8 |
619617 | Specimen | 31208-2 |
619618 | Tissue ID | 80398-1 |
619619 | Method | 48767-8 |
619620 | Disclaimer | 62364-5 |
619621 | Released By | 18771-6 |
Change Type | Effective Date |
---|---|
New Test | 2023-07-11 |