Synovial Sarcoma by Reverse Transcriptase PCR (RT-PCR), Paraffin
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Supporting a diagnosis of synovial sarcoma
Reflex Tests Lists test(s) that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial test(s)
|Test ID||Reporting Name||Available Separately||Always Performed|
|FSYT||SS18 (SYT), 18q11.2, FISH||Yes||No|
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 / AP Special Studies Review and 70011 / Slide Review. Additional testing may be performed after review by pathologist. Upon approval from the requesting clinician, 60254 / AP Special Studies Review could be changed to 70012 / Pathology Consultation, if determined to be more appropriate.
Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test
Reverse Transcriptase Polymerase Chain Reaction (RT-PCR)/Gel Electrophoresis
(PCR is utilized pursuant to a license agreement with Roche Molecular Systems, Inc.)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Synovial Sarcoma, RT-PCR, Paraffin
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 including a brief history is required.
Preferred: Formalin-fixed, paraffin-embedded (FFPE) tissue with a minimum of 10% tumor cell population
Acceptable: Unstained slides with a minimum of 10% tumor cell population; slides may be stained and/or scraped
Container/Tube: Surgical Pathology Packaging Kit (Supply T554) requested, but not required
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.
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 the referring physician may not be performed if deemed unnecessary by Mayo Clinic pathologist.
Forms: If not ordering electronically, submit a Pathology/Cytology Request Form (Supply T246) with the specimen.
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
Synovial sarcomas account for 9% to 10% of soft tissue tumors. These tumors occur in 2 major forms: biphasic and monophasic. Monophasic tumors are composed entirely of spindle cells, while biphasic tumors have epithelial cells arranged in glandular structures and mixed with spindle cells. The tumors are usually positive for keratin and epithelial membrane antigen as well as vimentin by immunostaining.
Synovial sarcoma is a member of the small round-cell tumor group that includes rhabdomyosarcoma, lymphoma, Wilms tumor, Ewing sarcoma, and desmoplastic small round-cell tumor. While treatment and prognosis depend on establishing the correct diagnosis, the diagnosis of sarcomas that form the small round-cell tumor group by light microscopic examination alone can be very difficult, especially true when only small-needle biopsy specimens are available for examination. The use of immunohistochemical stains (eg, keratin and epithelial membrane antigen [EMA]) can assist in establishing the correct diagnosis, but these markers are not entirely specific for synovial sarcoma. Expertise in soft tissue and bone pathology are often needed.
Studies have shown that some sarcomas have specific recurrent chromosomal translocations. These translocations produce highly specific gene fusions that help define and characterize subtypes of sarcomas and are useful in the diagnosis of these lesions.(1-4)
Cytogenetic studies have shown a distinctive chromosomal translocation, t(X;18)(p11;q11), in more than 90% of synovial sarcomas. Cloning of the translocation breakpoint showed that t(X;18) results in the fusion of 2 genes designated as SS18 (at 18q11) and SSX (at Xp11). Two closely related genes, SSX1 and SSX2, have 81% homology in proteins. SS18-SSX1 is present in 55% of cases, while SS18-SSX2 is present in 35% of cases. Patients with SS18-SSX2 translocation usually have greater metastasis-free survival than those with SS18-SSX1.
These fusion transcripts can be detected by reverse transcriptase PCR (RT-PCR), by FISH, chromogenic in situ hybridization (CISH), or by classical cytogenetic analyses. The RT-PCR and FISH procedures are the most sensitive methods to detect these fusion transcripts.(3)
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.
A positive SS18-SSX1 or SS18-SSX2 result is consistent with a diagnosis of synovial sarcoma.
Sarcomas other than synovial sarcoma, and carcinomas, melanomas, and lymphomas are negative for the fusion products.
A negative result does not rule out a diagnosis of synovial sarcoma.
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 tissues; other types of fixatives are discouraged. Improper treatment of tissues, such as decalcification, may cause PCR failure. False-negative results may occur in tumor specimens when tumor cells comprise <10% of the cell population. Tumor cells may be enriched by macrodissection to avoid false-negative results.
Clinical diagnosis and therapy should not be based solely on the results of this assay. The results should be considered in conjunction with clinical information, histologic evaluation, and additional diagnostic tests.
A total of 45 cases diagnosed as synovial sarcomas by soft tissue pathology experts and by immunohistochemical staining were analyzed. These consisted of 15 frozen tissue specimens and 30 paraffin sections. Three of the cases from frozen tissues and paraffin tissue sections were the same cases for direct comparison.
The primers used to detect common SS18-SSX1 and SS18-SSX2 resulted in a 130-bp fragment, while the SS18-SSX1 and SS18-SSX2 were 151 bp and 109 bp, respectively. For the frozen tissues, there were 12 (80%) SS18-SSX1-positive cases and 3 (20%) SS18-SSX2-positive cases. For paraffin sections, 27/30 (90%) of the cases were reactive. Paraffin sections had 19 of 27 (70.4%) SS18-SSX1 cases and 8 of 27 (29.6%) SS18-SSX2 cases. Southern hybridization and sequencing supported the ethidium bromide gel finding. Comparable RT-PCR results were obtained for the 3 cases that were analyzed by frozen and paraffin sections.
Analysis of other small round-cell tumors (alveolar rhabdomyosarcoma, desmoplastic round-cell tumor, and Ewing sarcoma) (n=12) were all negative for the SS18-SSX1/SSX2 transcripts. One of 8 malignant nerve-sheath tumors had a weak band for SS18-SSX1.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Crew AJ, Clark J, Fisher C, et al: Fusion of SYT to two genes SSX1 and SSX2 encoding proteins with homology to the Kruppel-associated box in human synovial sarcoma. EMBO J 1995;14:2333-2340
2. Clark J, Rocques PJ, Crew AJ, et al: Identification of novel genes, SYT and SSX, involved in the t(X;18)(p11.2;q11.2) translocation found in human synovial sarcoma. Nat Genet 1994;7:502-508
3. Kawaii A, Wodruff J, Healey JH, et al: SYT-SSX gene fusion as a determinant of morphology and prognosis in synovial sarcoma. N Engl J Med 1998;338:153-160
4. Jin L, Majerus J, Oliveira A, et al: Detection of fusion gene transcripts in fresh-frozen and formalin-fixed paraffin-embedded tissue sections of soft tissue sarcomas after laser capture microdissection and RT-PCR. Diagn Mol Pathol 2003;12:224-230
Method Description Describes how the test is performed and provides a method-specific reference
The paraffin-embedded tissue is deparaffinized. RNA is extracted using either the TRIzol kit (Invitrogen) or High Pure FFPE RNA Micro kit (Roche). DNase digestion is performed. RNA is converted to cDNA via reverse transcription (RT); the cDNA is amplified via PCR. Controls are run with each specimen to assess possible contamination issues and overall test performance. The PCR products are separated by gel electrophoresis and stained with ethidium bromide. The agarose gel is viewed under ultraviolet light and photographed to document the results. The results are interpreted and reported by a working group pathologist. In some cases, the specimen is further analyzed by FISH and sequencing.(Jin L, Majerus J, Oliveira A, et al: Detection of fusion gene transcripts in fresh-frozen and formalin-fixed paraffin-embedded tissue sections of soft tissue sarcomas after laser capture microdissection and RT-PCR. Diagn Mol Pathol 2003;12:224-230)
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 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.
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|
|83361||Synovial Sarcoma, RT-PCR, Paraffin||In Process|