Hematologic Neoplasms, TP53 Somatic Mutation, DNA Sequencing Exons 4-9, Varies

Casandra

Casandra Test Code MC74755Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID P53CACPT Code 81352

Hematologic Neoplasms, TP53 Somatic Mutation, DNA Sequencing Exons 4-9, Varies

Clinical Use

Use

The test is used for evaluating chronic lymphocytic leukemia patients at diagnosis or during the disease course to detect TP53 gene variants indicating high risk of disease progression and adverse outcomes. The presence of a TP53 gene variant in CLL offers important prognostic insights as it is the single most predictive tumor genetic abnormality for adverse outcomes and poor response to standard immunochemotherapy. However, alternative therapeutic options can be employed for affected patients.

Special Instructions

Ensure blood and bone marrow specimens arrive within 10 days of collection. Applicable mainly for high-risk CLL patients, but the TP53 gene sequencing can also be performed in other neoplasms as clinically indicated.

Limitations

The test cannot detect all possible TP53 variants since it is limited to somatic mutations within exons 4 to 9, though these regions cover more than 90% of disease-causing variants affecting critical DNA binding regions. Analytical sensitivity may vary depending on the B-cell number in samples and the subclonal nature of the genetic abnormality. Samples with low white blood cell counts or B-cell percentage may hinder optimal results.

Test Details

New York Approved