Li-Fraumeni Syndrome, TP53 Sequencing and Deletion/Duplication

Use

This test is used to identify individuals with Li‑Fraumeni syndrome by detecting single‑nucleotide variants, deletions, and duplications in the TP53 gene, which encodes the tumor suppressor protein p53. It is generally indicated for individuals meeting Chompret criteria — such as a tumor from the Li‑Fraumeni spectrum (e.g., soft tissue sarcoma, osteosarcoma, CNS tumor, breast cancer, adrenocortical carcinoma) diagnosed before age 46 plus a first‑ or second‑degree relative with an LFS tumor before age 56; individuals with multiple primary LFS tumors with the first before age 46; individuals with adrenocortical carcinoma, choroid plexus carcinoma, or rhabdomyosarcoma at any age; or individuals with breast cancer before age 31. Informed consent and genetic counseling are strongly recommended prior to testing. Results inform cancer risk assessment with guidance available from the NCCN, and positive results reflect pathogenic or likely pathogenic TP53 variants with autosomal dominant inheritance implications. Negative or VUS findings should be interpreted in context of personal and family history. Pathogenic/Likely pathogenic calls do not denote a current cancer diagnosis. VUS classification may evolve over time and requires clinical correlation. Quest also recommends annual variant review updates. Results typically return 14–21 days after receipt of a complete order. (Answers to Questions 1, 3, 7–10)

Not provided.