Appropriate initial test for Li-Fraumeni syndrome (LFS).
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Predisposition for developing early-onset and multiple primary cancers, particularly soft tissue and bone sarcomas, adrenocortical carcinoma, brain tumors, premenopausal breast cancer, and other malignancies.
Prevalence: 1 in 5,000-1 in 20,000.
Inheritance: Autosomal dominant.
Penetrance: Approximately 50 percent by age 30 years and 90 percent by age 60 years.
Cause: Pathogenic germline mutations in the TP53 gene.
Clinical Sensitivity: Approximately 80 percent for individuals meeting classic Li-Fraumeni syndrome (LFS) criteria.
Methodology: Bidirectional sequencing of all coding regions and intron-exon boundaries of the TP53 gene.
Analytical Sensitivity and Specificity: Greater than 95 percent.
Limitations:TP53 gene regulatory region mutations, deep intronic mutations, and large deletions/duplications will not be detected. Diagnostic errors can occur due to rare sequence variations.
|Component Test Code*||Component Chart Name||LOINC|
|2009303||Li-Fraumeni (TP53) Sequencing Specimen|
|2009304||Li-Fraumeni (TP53) Sequencing Interp|