Home
HelpTest Code MAMLF MAML2 (11q21) Rearrangement, Mucoepidermoid Carcinoma (MEC), FISH, Tissue
Reporting Name
MAML2 (11q21), FISH, TsUseful For
Supporting the diagnosis of mucoepidermoid carcinoma when used in conjunction with an anatomic pathology consultation
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| _PBCT | Probe, +2 | No, (Bill Only) | No |
| _PADD | Probe, +1 | No, (Bill Only) | No |
| _PB02 | Probe, +2 | No, (Bill Only) | No |
| _PB03 | Probe, +3 | No, (Bill Only) | No |
| _IL25 | Interphases, <25 | No, (Bill Only) | No |
| _I099 | Interphases, 25-99 | No, (Bill Only) | No |
| _I300 | Interphases, >=100 | No, (Bill Only) | No |
Testing Algorithm
This test includes a charge for application of the first probe set (2 FISH probes) and professional interpretation of results.
Additional charges will be incurred for all reflex probes performed. Analysis charges will be incurred based on the number of cells analyzed per probe set. If no cells are available for analysis, no analysis charges will be incurred.
Appropriate ancillary probes may be performed at consultant discretion to render comprehensive assessment. Any additional probes will have the results included within the final report and will be performed at an additional charge.
Method Name
Fluorescence In Situ Hybridization (FISH)
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
TissueOrdering Guidance
This test does not include a pathology consultation. If a pathology consultation is requested, order PATHC / Pathology Consultation, and appropriate testing will be added at the discretion of the pathologist and performed at an additional charge.
Multiple oncology (cancer) gene panels are also available. For more information see Hematology, Oncology, and Hereditary Test Selection Guide.
Shipping Instructions
Advise Express Mail or equivalent if not on courier service.
Necessary Information
1. A pathology report is required for testing to be performed. If not provided, appropriate testing and interpretation may be compromised or delayed. Acceptable pathology reports include working drafts, preliminary pathology, or surgical pathology reports.
2. The following information must be included in the report provided:
-Patient name
-Block number - must be on all blocks, slides, and paperwork
-Date of collection
-Tissue source
3. A reason for testing must be provided. If this information is not provided, an appropriate indication for testing may be entered by Mayo Clinic Laboratories.
Specimen Required
Submit only 1 of the following specimens:
Preferred:
Specimen Type: Tissue block
Collection Instructions: Submit a formalin-fixed, paraffin-embedded tumor tissue block. Blocks prepared with alternative fixation methods will be attempted but are less favorable for successful results by fluorescence in situ hybridization testing; provide fixation method used.
Additional Information:
1. Paraffin-embedded specimens can be from any anatomic location (skin, soft tissue, lymph node, etc).
2. Bone specimens that have been decalcified will be attempted for testing, but the success rate is approximately 50%.
??
Acceptable:
Specimen Type: Tissue slides
Slides: 1 Hematoxylin and eosin stained and 4 unstained
Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 4 consecutive unstained, positively charged, unbaked slides with 5 micron-thick sections of the tumor tissue.
Specimen Minimum Volume
Slides: 1 Hematoxylin and eosin stained and 2 unstained
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Tissue | Ambient (preferred) | ||
| Refrigerated | |||
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
CPT Code Information
88271x2, 88291-DNA probe, each (first probe set), Interpretation and report
88271x2-DNA probe, each; each additional probe set (if appropriate)
88271x1-DNA probe, each; coverage for sets containing 3 probes (if appropriate)
88271x2-DNA probe, each; coverage for sets containing 4 probes (if appropriate)
88271x3-DNA probe, each; coverage for sets containing 5 probes (if appropriate)
88274 w/modifier 52-Interphase in situ hybridization, <25 cells, each probe set (if appropriate)
88274-Interphase in situ hybridization, 25 to 99 cells, each probe set (if appropriate)Â Â Â Â Â Â Â Â
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| MAMLF | MAML2 (11q21), FISH, Ts | 74034-0 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 54689 | Result Summary | 50397-9 |
| 54692 | Interpretation | 69965-2 |
| 54691 | Result | 62356-1 |
| CG930 | Reason For Referral | 42349-1 |
| 54918 | Specimen | 31208-2 |
| 54694 | Source | 31208-2 |
| 54695 | Tissue ID | 80398-1 |
| 55136 | Method | 85069-3 |
| 55137 | Additional Information | 48767-8 |
| 53394 | Disclaimer | 62364-5 |
| 54696 | Released By | 18771-6 |
Clinical Information
Mucoepidermoid carcinoma is the most common malignant salivary gland neoplasm, representing over 30% of all malignant salivary gland tumors. Mucoepidermoid carcinoma can arise in other locations such as the lung and airways. The diagnosis can be quite challenging due to the degree of histologic overlap with other tumors. MAML2 rearrangements are detectable in 80% to 85% of mucoepidermoid carcinomas but not in morphologic mimics.
MAML2 rearrangements can be identified in numerous neoplasms in addition to mucoepidermoid carcinoma including, but not limited to, hidradenoma, poroma, porocarcinoma, and hemangioendothelioma.
Interpretation
MAML2 will be clinically interpreted as positive, negative, or equivocal.
A MAML2 abnormality is detected when the percent of cells with an abnormality exceeds the normal cutoff for the MAML2 probe set.
A positive result is consistent with rearrangement of the MAML2 gene and likely reflects MAML2 fusion with a partner gene. The significance of this finding is dependent on the clinical and pathologic features.
A negative result suggests a MAML2 gene rearrangement is not present but does not exclude a MAML2 rearrangement.
Cautions
This test is not approved by the US Food and Drug Administration, and it is best used as an adjunct to existing clinical and pathologic information.
This fluorescence in situ hybridization (FISH) assay does not rule out other chromosome abnormalities.
Fixatives other than formalin (eg, Prefer, Bouin's) may not be successful for FISH assays. Non-formalin fixed specimens will not be rejected.
Paraffin-embedded tissues that have been decalcified may not be successful for FISH analysis. The success rate of FISH studies on decalcified tissue is approximately 50%, but FISH will be attempted if sufficient tumor is present for analysis.
FISH studies will be attempted if sufficient tumor is present for analysis. The pathologist reviewing the hematoxylin and eosin-stained slide may find it necessary to cancel testing if insufficient tissue/tumor is available for testing.
If no FISH signals are observed post hybridization, the case will be released indicating a lack of FISH results.
Supportive Data
FISH analysis was performed on 28 mucoepidermoid carcinoma (MEC) formalin-fixed paraffin-embedded tissue samples and 51 control specimens. The normal controls were used to generate a normal cutoff for this assay. A rearrangement of MAML2 was identified in 26 of 28 (93%) MEC cases.
Clinical Reference
1. Seethala RR, Dacic S, Cieply K, Kelly LM, Nikiforova MN. A reappraisal of the MECT1/MAML2 translocation in salivary mucoepidermoid carcinomas. Am J Surg Pathol. 2010;34(8):1106-1121
2. Behboudi A, Enlund F, Winnes M, et al. Molecular classification of mucoepidermoid carcinomas-prognostic significance of the MECT1-MAML2 fusion oncogene. Genes Chromosomes Cancer. 2006;45(5):470-481
3. Salem A, Bell D, Sepesi B, et al. Clinicopathologic and genetic features of primary bronchopulmonary mucoepidermoid carcinoma: the MD Anderson Cancer Center experience and comprehensive review of the literature. Virchows Archiv. 2017;470(6):619-26
4. Kuma Y, Yamada Y, Yamamoto H, et al. A novel fusion gene CRTC3-MAML2 in hidradenoma: histopathological significance. Hum Pathol. 2017;70:55-61
5. Sekine S, Kiyono T, Ryo E, et al. Recurrent YAP1-MAML2 and YAP1-NUTM1 fusions in poroma and porocarcinoma. J Clin Invest. 2019;129(9):3827-3832
6. Antonescu CR, Dickson BC, Sung YS, et al. Recurrent YAP1 and MAML2 gene rearrangements in retiform and composite hemangioendothelioma. Am J Surg Pathol. 2020;44(12):1677-1684
Method Description
The test is performed using a laboratory-developed MAML2 dual-color, break-apart strategy probe. Formalin-fixed, paraffin-embedded tissues are cut at 5 microns and mounted on positively charged glass slides. The selection of tissue and the identification of target areas on the hematoxylin and eosin (H and E)-stained slide are performed by a pathologist. Using the H and E-stained slide as a reference, target areas are etched with a diamond-tipped engraving tool on the back of the unstained slide to be assayed. The probe set is hybridized to the appropriate target areas, and 2 technologists independently analyze 50 interphase nuclei (100 total) with the results expressed as the percent of abnormal nuclei.(Unpublished Mayo method)
Report Available
7 to 10 daysSpecimen Retention Time
Slides and H and E used for analysis are retained by the laboratory in accordance with regulatory requirements. Client provided paraffin blocks and extra unstained slides (if provided) will be returned after testing is complete.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.Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.