MAML2 (11q21), Mucoepidermoid Carcinoma (MEC)
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Supporting a diagnosis of mucoepidermoid carcinoma
Additional Tests Lists test(s) that are always performed, at an additional charge, with the initial test(s)
|Test ID||Reporting Name||Available Separately||Always Performed|
|60254||AP Special Studies Review||No||Yes|
Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
This test is performed in conjunction with 60254 Anatomic Pathology Special Studies Review. Additional testing may be performed after review by pathologist. Upon approval from the requesting clinician, 60254 Anatomic Pathology Special Studies Review could be changed to 70012 Pathology Consultation, if determined to be more appropriate.
Fluorescence In Situ Hybridization (FISH) with DNA probes
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
MAML2 (11q21), FISH
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
A pathology/diagnostic report and a brief history are required.
Preferred: Formalin-fixed, paraffin-embedded (FFPE) tissue block
Acceptable: Unstained glass, "positively charged" slides with FFPE tissue; slides may be stained
1. Process all specimens into FFPE blocks prior to submission.
2. If submitting slides, a minimum of ten, 4- to 5-micron thick, unstained slides are required if also requesting a surgical pathology consultation; a minimum of three, 4- to 5-micron thick, unstained slides are required if not requesting a surgical pathology consultation.
1. A quality specimen is essential for evaluation. Submit only tissue containing tumor cells; minimal tissue is required for evaluation.
2. Special stains performed outside Mayo Medical Laboratories and included with the case may be repeated and charged at the reviewing pathologist's discretion. Testing requested by referring physician may not be performed if deemed unnecessary by Mayo Clinic pathologist.
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland neoplasm, representing over 30% of all malignant salivary gland tumors. The diagnosis of MEC can be quite challenging due to the degree of histologic overlap with other glandular, clear cell, or oncocytic salivary gland tumors. MAML2 fusions are detectable in 80% to 85% of MEC, but not in morphologic mimics such as oncocytic cystadenoma, Warthin tumor, oncocytoma, oncocytic carcinoma, acinic cell carcinoma, and metastatic renal cell carcinoma.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
0-9% rearranged cells
A positive test is consistent with a diagnosis of mucoepidermoid carcinoma (MEC). A negative test does not rule out the diagnosis of MEC. Carcinomas such as salivary duct carcinoma, adenosquamous carcinoma, acinic cell carcinoma, and Warthin tumor are negative for the MAML2 rearrangements.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Reliable results are dependent on adequate specimen collection and processing. This test has been validated on formalin-fixed, paraffin-embedded tissue; other types of fixatives are discouraged. Improper treatment of tissues, such as decalcification, may cause FISH failure.
Clinical diagnosis and/or therapy should not be based solely on this assay. The results should be considered in conjunction with clinical information and/or additional diagnostic tests.
A blinded investigation was performed on 28 MEC and 51 control tissues. All samples were identified and diagnosed by a soft tissue pathology expert. Two technologists scored 100 cells each. The MAML2 locus was found to be rearranged in 26 of 28 MEC cases (93%) and 0 of 51 control cases.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Stewart FW, Foote FW, Becker WF: Mucoepidermoid tumors of salivary glands. Ann Surg 1945;122:820-844
2. Spiro RH, Huvos AG, Berk R, Strong EW: Mucoepidermoid carcinoma of salivary gland origin. A clinicopathologic study of 367 cases. Am J Surg 1978;136:461-468
3. Seethala RR, Dacic S, Cieply K, et al: A reappraisal of the MECT1/MAML2 translocation in salivary mucoepidermoid carcinomas. Am J Surg Pathol 2010 Aug;34(8):1106-1121
4. 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 May;45(5):470-481
Method Description Describes how the test is performed and provides a method-specific reference
Formalin-fixed, paraffin-embedded tissues are cut at 4 micrometers and mounted on positively charged glass slides. Five slides are prepared, 1 to 2 slides are stained with hematoxylin and eosin; the remaining 3 are unstained. The selection of tissue and the identification of target areas on an hematoxylin and eosin-stained slide are performed by a pathologist. Using the hematoxylin and eosin slide as a reference, target areas are etched with a diamond-tipped etcher on the back of the unstained slide. Abnormalities involving the MAML2 locus at 11q21 locus are detected using a FISH break-apart probe (BAP).(Mayo Clinic) The probe design consists of DNA derived from bacterial artificial chromosomes (BAC) flanking the MAML2 locus. The 5' end is labeled with Spectrum Orange (R) and the 3' end is labeled with Spectrum Green (G). When the MAML2 locus is intact there will be 2F (2 fused signals) where the red and green probes overlap producing a yellow signal. The probe set is applied to the appropriate target areas, denatured, and hybridized overnight. Two independent technologists analyze 100 interphase nuclei each (200 total). Abnormal nuclei can have many different signal patterns. Examples include: 1F+1R, 1F+1G, or 1F+1R+1G. The sample is positive if there are a combined total of >10% abnormal cells. Results are reported as positive or negative for MAML2 locus rearrangement in ISCN nomenclature. The results are interpreted and reported by a working group pathologist.(Seethala RR, Dacic S, Cieply K, et al: A reappraisal of the MECT1/MAML2 translocation in salivary mucoepidermoid carcinomas. Am J Surg Pathol 2010 Aug;34:1106-1121)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 8 a.m.-5:00 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
1 week/7 days
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
MAML2 (11q21), Mucoepidermoid Carcinoma (MEC)
88368-Morphometric analysis, in situ hybridization (quantitative or semi-quantitative) each probe; manual
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|61219||MAML2 (11q21), Mucoepidermoid Carcinoma (MEC)||74034-0|