KRAS Somatic Mutation Analysis, Peritoneal Fluid

Casandra

Casandra Test Code MC67160Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID KRASWCPT Codes 81275, 81276

KRAS Somatic Mutation Analysis, Peritoneal Fluid

Clinical Use

Use

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 KRAS oncogene is the most frequently mutated oncogene in 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 carbohydrate antigen 19-9 and/or carcinoembryonic antigen and may portend an increased risk of residual/recurrent pancreatic cancer metastases within the peritoneal cavity.

Special Instructions

A pathology report (final or preliminary) is required and must accompany specimen for testing. The report must include patient name, second identifier, date of fluid collection, and source of the fluid.

Limitations

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.

Test Details

New York Approved