FISH, MDM2 12q15/CEP 12

92216

If results are not possible from the submitted specimen, the test order will be cancelled and replaced by non-orderable test Cytogenetics Communication.

Formalin-fixed paraffin-embedded tissue block

3 slides

5 slides, unstained (5-micron) slides on positively charged (+) slides

Do not reject specimens, send to laboratory for screening. Paraffin block is the preferred sample type. Sample source and block ID are required on the requisition form and a pathology report must be submitted.

Send specimen to testing lab for determination. Do not freeze. Do not reject.

Room temperature

Room temperature: Acceptable
Refrigerated: Preferred
Frozen: Unacceptable

See Collection Instructions

Set up: Daily; Report available: 5-7 days

See Laboratory Report

The differential morphological diagnosis of soft tissue tumors is often complex, including benign versus malignant and sarcoma versus other neoplasms. The dual color MDM2/CEP12 probe set is used to evaluate cultured cells and interphase cells from FFPE for relative gain/ amplification of the MDM2 (transformed mouse 3T3 cell double minute, p53 binding protein) gene at band 12q15. MDM2 amplification may be found in a number of cancers, such as osteosarcomas, esophageal carcinomas, and other soft tissue derived tumors. MDM2 is implicated in a number of cancers due to its relationship with the p53 tumor suppressor gene. As a ubiquitin-protein ligase that promotes p53 degradation, overexpression of the MDM2 gene can contribute to the oncogenesis. Liposarcomas often have complex karyotypes, including large ring chromosomes and giant chromosomes. Molecular characterization using FISH probes is especially useful in differentiating between benign lipomas which are disomic for MDM2 and well differentiated liposarcoma and dedifferentiated liposarcoma which exhibit MDM2 gain/amplification.