Test ID KRASW KRAS Somatic Mutation Analysis, Peritoneal Fluid
Shipping Instructions
Send specimens refrigerated (4° C)
Necessary Information
Pathology report (final or preliminary) is required and must accompany specimen for testing to be performed. At minimum, it should contain the following information:
1. Patient name and second identifier
2. Fluid collection date
3. Source of the fluid
Specimen Required
Container/Tube: 50-mL Falcon tube
Preferred: Fresh, peritoneal washing; no fixatives added to wash
Specimen Volume: Two 50-mL Falcon tubes
Collection Instructions: Containers must be labeled with two unique patient identifiers.
Forms
Molecular Genetics: Inherited Cancer Syndromes Patient Information (T519)
Secondary ID
616452Useful For
Staging of the pancreatic ductal adenocarcinoma.(1)
Special Instructions
Method Name
Droplet Digital Polymerase Chain Reaction (ddPCR)
Reporting Name
KRAS Mutation Analysis, PeritonealSpecimen Type
VariesSpecimen Minimum Volume
100 mL of peritoneal washing
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Varies | Refrigerated |
Clinical Information
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with predilection for peritoneal dissemination. Accurate peritoneal staging is important for management of patients with PDAC. The Kirsten RAS (KRAS) oncogene is the most commonly mutated oncogene in pancreatic ductal adenocarcinoma (PDAC). Detection of KRAS mutations within peritoneal fluid has been associated with clinically positive laparoscopic findings (gross metastases and/or positive peritoneal cytology) and elevated peritoneal fluid CA19-9 and/or carcinoembryonic antigen and may portend an increased risk of residual/recurrent pancreatic cancer metastases within the peritoneal cavity.
This test uses DNA extracted from cells shed into the peritoneum to evaluate for the presence of KRAS (G12A, G12C, G12D, G12R, G12S, G12V, G13D, Q61K, Q61L, Q61R, Q61H, and A146T) mutations. A positive result indicates the presence of an activating KRAS mutation and can be a useful marker to aid in the staging of pancreatic ductal adenocarcinoma.
Reference Values
An interpretive report will be provided.
Cautions
Patients with a negative test result may still harbor a KRAS mutation below the level of detection.
The limit of detection of this assay is influenced by the amount of cells and DNA in the peritoneal wash. This is a biological variable that cannot be controlled.
This assay was designed to detect mutations in KRAS codons 12, 13, 61, and 146 (G12A, G12C, G12D, G12R, G12S, G12V, G13D, Q61K, Q61L, Q61R, Q61H, and A146T).
This test has not been clinically validated for use as a tool to monitor response to therapy or for early detection of tumors.
This test cannot differentiate between somatic and germline alterations.
Day(s) Performed
Monday through Friday
Report Available
4 to 10 daysPerforming Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81275-KRAS (v-Ki-ras2 Kirsten rat sarcoma viral oncogene) (eg, carcinoma) gene analysis, variants in codons 12 and 13
81276-KRAS (v-Ki-ras2 Kirsten rat sarcoma viral oncogene) (eg, carcinoma) gene analysis, additional variants
81479 (if appropriate for government payers)