Order Code P53CA Hematologic Neoplasms, TP53 Somatic Mutation, DNA Sequencing Exons 4-9, Varies
Useful For
Evaluating chronic lymphocytic leukemia patients at diagnosis or during disease course for the presence of TP53 gene variants indicating high risk of disease progression and adverse outcomes
This test is not intended for the evaluation of patients suspected of having an inherited or germline TP53 cancer syndrome (eg, Li Fraumeni syndrome)
Testing Algorithm
Flow cytometry will be performed on peripheral blood samples to verify diagnosis of chronic lymphocytic leukemia (CLL) and to selectively enrich for B cells in samples with a clonal population.
For more information see TP53 Sequencing Testing Algorithm.
Reporting Name
TP53 gene somatic mutation analysisSpecimen Type
VariesOrdering Guidance
For the evaluation of patients suspected of having an inherited or germline TP53 cancer syndrome (eg, Li Fraumeni syndrome), order one of the following tests containing TP53:
-XCP/ Hereditary Expanded Cancer Panel, Varies
-COMCP / Hereditary Common Cancer Panel, Varies
-BRGYP / Hereditary Breast/Gynecologic Cancer Panel, Varies
-CRCGP / Hereditary Gastrointestinal Cancer Panel, Varies
-PANCP / Hereditary Pancreatic Cancer Panel, Varies
-ENDCP / Hereditary Endocrine Cancer Panel, Varies
-THYRP / Hereditary Thyroid Cancer Panel, Varies
-WILMP / Hereditary Wilms Tumor Panel, Varies
-RENCP / Hereditary Renal Cancer Panel, Varies
-PRS8P / Hereditary Prostate Cancer Panel, Varies
Shipping Instructions
Blood and bone marrow specimens must arrive within 10 days of collection.
Necessary Information
The following information is required:
1. Pertinent clinical history
2. Clinical or morphologic suspicion
3. Date of collection
4. Specimen source
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Blood (preferred)
Container/Tube: Lavender top (EDTA) or yellow top (ACD solution B)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
3. Label specimen as blood.
Specimen Stability Information: Ambient/Refrigerate <10 days
Specimen Type: Bone marrow
Container/Tube: Lavender top (EDTA), yellow top (ACD solution B), or green top (heparin)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix bone marrow.
2. Send bone marrow specimen in original tube. Do not aliquot.
3. Label specimen as bone marrow.
Specimen Stability Information: Ambient/Refrigerate <10 days
Specimen Type: Tissue
Container/Tube: Plastic container
Specimen Volume: 100 mg
Collection Instructions: Stabilize fresh tissue in tissue culture medium or freeze immediately after collection.
Specimen Stability Information: Refrigerate 24 hours/ Frozen
Specimen Minimum Volume
Blood, bone marrow: 1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies | 10 days |
Reject Due To
Gross hemolysis | Reject |
Extracted DNA | Reject |
Moderately to severely clotted Formalin-fixed paraffin-embedded tissue |
Reject |
Reference Values
Genetic variants present or absent as compared to a reference sequence of the normal TP53 gene
Method Description
Peripheral blood specimens from chronic lymphocytic leukemia (CLL) patients only will be analyzed by a screening flow cytometry method to determine B-cell content and confirm the presence of a clonal B-cell population. Blood (but not bone marrow) samples from patients with CLL are enriched for B lymphocytes by cell sorting, and DNA is extracted from the B-cell fraction. For other sample types (bone marrow, fresh or frozen tissues) DNA is extracted directly without prior enrichment. Polymerase chain reaction and Sanger sequencing of TP53 exons 4 to 9 is performed. Sequence analysis is performed using Mutation Surveyor and Alamut software. The presence of a detected variant is then assessed using curated public databases of known TP53 gene mutations.(National Cancer Institute: The TP53 Database. National Institutes of Health; 2022. Accessed October 5, 2022. Available at https://tp53.isb-cgc.org/; den Dunnen JT, Antonarakis SE: Mutation nomenclature extensions and suggestions to describe complex mutations: a discussion. Hum Mutat. 2000;15:7-12)
Day(s) Performed
Monday through Friday
Performing Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
81352-TP53 (tumor protein 53) (eg, tumor samples), full gene sequence or targeted sequence analysis of >5 exons
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
CSP53 | TP53 Pre-Analysis Cell Sorting, V | No | No |
Special Instructions
Method Name
Polymerase Chain Reaction (PCR) and Sanger Sequencing
Forms
2. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.