Sign in →

Test Code MISC2MAYOCRCGP Hereditary Gastrointestinal Cancer Panel, Varies


Ordering Guidance


Customization of this panel and single gene analysis for any gene present on this panel are available. For more information see CGPH / Custom Gene Panel, Hereditary, Next-Generation Sequencing, Varies.

 

Targeted testing for familial variants (also called site-specific or known mutations testing) is available for the genes on this panel. For more information see FMTT / Familial Variant, Targeted Testing, Varies. To obtain more information about this testing option, call 800-533-1710.



Shipping Instructions


Specimen preferred to arrive within 96 hours of collection.



Necessary Information


Prior Authorization is available, but not required, for this test. If proceeding with the prior authorization process, submit the required form with the specimen.



Specimen Required


Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.

Specimen Type: Whole blood

Container/Tube:

Preferred: Lavender top (EDTA) or yellow top (ACD)

Acceptable: Any anticoagulant

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send whole blood specimen in original tube. Do not aliquot.

Specimen Stability Information: Ambient (preferred) 4 days/Refrigerated


Forms

1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file.

-Informed Consent for Genetic Testing  (T576)

-Informed Consent for Genetic Testing (Spanish) (T826)

2. Molecular Genetics: Inherited Cancer Syndromes Patient Information Sheet (T519)

3. Hereditary Gastrointestinal Cancer Panel Prior Authorization Ordering Instructions

4. If not ordering electronically, complete, print, and send a Oncology Test Request (T729) with the specimen.

Secondary ID

614571

Useful For

Evaluating patients with a personal or family history suggestive of a hereditary gastrointestinal cancer or hereditary polyposis syndrome

 

Establishing a diagnosis of a hereditary gastrointestinal cancer syndrome or hereditary polyposis syndrome allowing for targeted cancer surveillance based on associated risks

 

Identifying genetic variants associated with increased risk for gastrointestinal cancer and polyposis, allowing for predictive testing and appropriate screening of at-risk family members

Testing Algorithm

First-tier testing may be considered/recommended. For more information see Lynch Syndrome Testing Algorithm.

Method Name

Sequence Capture and Next-Generation Sequencing (NGS), Polymerase Chain Reaction (PCR), Sanger Sequencing and/or Multiplex Ligation-Dependent Probe Amplification (MLPA)

Reporting Name

Hereditary GI Cancer Panel

Specimen Type

Varies

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Varies

Reject Due To

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Clinical Information

Colorectal cancer occurs in approximately 4% to 6% of individuals in the general population.(1) In some cases, individuals with a personal or family history of colorectal cancer, gastric cancer, or polyposis may be at increased risk of cancer due to a hereditary cancer syndrome.(2,3) Evaluation of the genes on this panel may be useful for families with a history of colorectal cancer, gastric cancer, polyposis, or gastrointestinal cancers to determine cancer risk, surveillance recommendations, and targeted treatments.(2-4)

 

The most common hereditary colon cancer syndrome is Lynch syndrome, accounting for about 2% to 4% of all colon cancer cases.(2) Lynch syndrome is associated with germline variants in the mismatch repair genes, MLH1, MSH2, MSH6, PMS2, or deletions of the EPCAM gene.(2,3) It is predominantly characterized by significantly increased risks for colorectal and endometrial cancer.(2,3) The lifetime risk for colorectal cancer is highly variable and dependent on the gene involved.(2,3) Other malignancies within the tumor spectrum include gastric cancer, ovarian cancer, hepatobiliary and upper tract urothelial carcinomas, and small bowel cancer.(2,3)

 

Although rare, individuals and families with polyposis may also be at risk for a hereditary polyposis syndrome, such as familial adenomatous polyposis (FAP).(2) FAP is caused by variants in the APC gene and characterized by numerous adenomatous polyps.(2) The presence of extracolonic manifestations is variable and includes gastric and duodenal polyps, ampullary polyps, osteomas, dental abnormalities (unerupted teeth), congenital hypertrophy of the retinal pigment epithelium (CHRPE), benign cutaneous lesions, desmoid tumors, hepatoblastoma, and extracolonic cancers.(2)

 

Other genes are also known to cause to hereditary colorectal cancer, gastric cancer, polyposis, and gastrointestinal cancers.(2) The risk for developing cancer associated with these syndromes varies.(2) Some individuals with a disease-causing variant in one of these genes develop multiple primary cancers.(2)

 

The National Comprehensive Cancer Network and the American Cancer Society provide recommendations regarding the medical management of individuals with hereditary gastrointestinal cancer syndromes.(2,4)

Reference Values

An interpretive report will be provided.

Interpretation

All detected variants are evaluated according to American College of Medical Genetics and Genomics recommendations.(5) Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.

Method Description

Next-generation sequencing (NGS) and/or Sanger sequencing are performed to test for the presence of variants in coding regions and intron/exon boundaries of the genes analyzed, as well as some other regions that have known disease-causing variants. The human genome reference GRCh37/hg19 build was used for sequence read alignment. At least 99% of the bases are covered at a read depth over 30X. Sensitivity is estimated at above 99% for single nucleotide variants, above 94% for deletions-insertions (delins) less than 40 base pairs (bp), above 95% for deletions up to 75 bp and insertions up to 47 bp. NGS, multiplex ligation-dependent probe amplification (MLPA), and/or a polymerase chain reaction (PCR)-based quantitative method is performed to test for the presence of deletions and duplications in the genes analyzed. PCR and gel electrophoresis is performed to test for the presence of the 10 megabase inversion of coding exons 1-7 of the MSH2 gene.

 

There may be regions of genes that cannot be effectively evaluated by sequencing or deletion and duplication analysis as a result of technical limitations of the assay, including regions of homology, high guanine-cytosine (GC) content, and repetitive sequences. For details regarding the targeted genes analyzed and specific gene regions not routinely covered, see Targeted Genes and Methodology Details for Hereditary Gastrointestinal Cancer Panel.(Unpublished Mayo method)

 

Confirmation of select reportable variants may be performed by alternate methodologies based on internal laboratory criteria.

 

Genes analyzed: APC (including promoters 1A and 1B), ATM, AXIN2, BMPR1A, CDH1, CHEK2, CTNNA1, EPCAM (copy number variants only), GREM1 (upstream enhancer region duplication only), KIT, MLH1, MLH3, MSH2, MSH3, MSH6, MUTYH, NTHL1, PDGFRA, PMS2, POLD1, POLE, PTEN (including promoter), RNF43, SMAD4, STK11, TP53

Day(s) Performed

Varies

Report Available

21 to 28 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test 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

81435

LOINC Code Information

Test ID Test Order Name Order LOINC Value
CRCGP Hereditary GI Cancer Panel 97656-3

 

Result ID Test Result Name Result LOINC Value
614695 Test Description 62364-5
614696 Specimen 31208-2
614697 Source 31208-2
614698 Result Summary 50397-9
614699 Result 82939-0
614700 Interpretation 69047-9
614701 Resources 99622-3
614702 Additional Information 48767-8
614703 Method 85069-3
614704 Genes Analyzed 48018-6
614705 Disclaimer 62364-5
614706 Released By 18771-6

Prior Authorization

Insurance preauthorization is available for this testing; forms are available.

 

Patient financial assistance may be available to those who qualify. Patients who receive a bill from Mayo Clinic Laboratories will receive information on eligibility and how to apply.