MAML2 (11q21), Mucoepidermoid Carcinoma (MEC)
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