What is a KRAS mutation test?
KRAS mutation detection is a test intended for knowing the presence of KRAS gene mutation in patient of lung cancer, colon cancer ,pancreatic cancer .The KRAS gene produces a protein that plays an important role in cell growth and division. Mutations in the KRAS gene can lead to uncontrolled cell growth, which can eventually lead to cancer.
This test is often used to help doctors decide which treatment options are best for people with cancer.
Which cancers are associated with KRAS mutation?
KRAS mutations are found in a variety of cancers, including colorectal cancer, pancreatic cancer, lung cancer, and breast cancer. KRAS drives approximately 32% of lung cancers, 40% of colorectal cancers, and 85% to 90% of pancreatic cancer cases.
What are the most common KRAS mutations?
The most common KRAS mutations are found in codons 12 and 13. These mutations are called G12C and G13D, respectively.
How is a KRAS mutation test performed?
The test is usually performed on a tissue sample obtained from a biopsy or surgical procedure. The sample is then sent to a laboratory, where techniques like PCR ,Pyrosequencing, DNA sequencing techniques are used to analyze the KRAS gene for any mutations .The best way to identify biomarkers in cancer is through comprehensive next-generation sequencing (NGS).
which sample is requirement for KRAS testing?
sample stored in 10% buffered formalin or formalin fixed and paraffin embedded(FFPE) tissue biopsy .Fine needle aspirate FFPE cell blocks
The use of alternative fixatives, such as mercury-based or alcohol-based fixatives, should be avoided.
What is the significance of a KRAS mutation test?
The results of a KRAS mutation test can have a significant impact on treatment decisions. For example, people with KRAS mutations are not typically good candidates for treatment with certain types of cancer drugs, such as erlotinib, cetuximab and panitumumab.
KRAS mutation and lung cancer
KRAS mutations are commonly found in various types of cancer, including lung cancer. In non-small cell lung cancer (NSCLC), which is the most prevalent type of lung cancer, KRAS mutations are one of the most frequently occurring genetic alterations.
KRAS gene mutations are much more common in long-term tobacco smokers with lung cancer than in nonsmokers. KRAS G12C accounts for approximately 50% of KRAS mutations in NSCLC and is present in approximately 14% of patients with NSCLC.
Lung cancers with KRAS gene mutations typically indicate a poor prognosis and are associated with resistance to several cancer treatments. One of the critical aspects of KRAS mutations in NSCLC is their impact on treatment response. Patients with KRAS mutations have been shown to have a poorer prognosis compared to those without these mutations. Moreover, they tend to be less responsive to certain targeted therapies, such as epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) like erlotinib
Sotorasib and Adagrasib are two KRAS G12C inhibitors that have shown efficacy in patients with NSCLC. Other novel KRAS inhibitors are being studied in early-phase trials. Sotorasib and Adagrasib are indicated for KRAS G12C–mutated locally advanced or metastatic NSCLC in adults who have received 1 or more prior systemic therapies.
All patients with NSCLC should have their tumor tissue tested for mutations, such as in the genes that code for epidermal growth factor receptor (EGFR), KRAS, anaplastic lymphoma kinase (ALK), ROS1, and for programmed death ligand–1 (PDL-1). The results will help determine the patient’s eligibility for treatment with specific molecular-targeted agents.
Colorectal Cancer and KRAS
KRAS-driven Colorectal cancers are difficult to treat .The presence of a KRAS mutation can have a significant impact on treatment options. For example, people with KRAS mutations are not typically good candidates for treatment with EGFR targeted therapy , such as cetuximab and panitumumab.
What are the limitations of a KRAS mutation test?
The KRAS mutation test can be falsely negative if tumor content is low in biopsy.
Who should get a KRAS mutation test?
A KRAS mutation test may be recommended for people with certain types of cancer, such as colorectal cancer, pancreatic cancer, and lung cancer.
What are the implications of a positive KRAS mutation test result?
A positive KRAS mutation test result means that the person may not be a good candidate for treatment with EGFR targeted therapy. However, there are other types of cancer treatment that may be effective. If you have any questions about KRAS mutation tests, talk to your doctor.
What are the implications of a negative KRAS mutation test result?
A negative KRAS mutation test result means that the person may be a good candidate for treatment with targeted therapy . However, it is important to note that a negative result does not guarantee that the person will respond to targeted therapy.