Molecular Genetic EGFR, ALK, ROS1, PDL1 - FISH & RT-PCR
Test Code
MOG38
Also Known As
No data available
Test Parameters Included
No data available
Department
MOLECULAR GENETICS
Methodology
FISH (Fluorescence In Situ Hybridization) / RT-PCR (Reverse Transcription Polymerase Chain Reaction) / IHC (Immunohistochemistry)
This comprehensive molecular genetic test employs a multi-modality approach to detect critical genomic alterations and protein expression levels in tumor tissue, which are crucial for guiding targeted therapies, particularly in Non-Small Cell Lung Cancer (NSCLC). The methodologies are:
* FISH (Fluorescence In Situ Hybridization): This technique is primarily used for detecting gene rearrangements (translocations) or amplifications. It uses fluorescently labeled DNA probes that bind to specific target sequences on chromosomes. When illuminated under a fluorescence microscope, the presence, absence, or rearrangement of these signals indicates the status of the gene.
* ALK (Anaplastic Lymphoma Kinase): FISH is the gold standard for detecting ALK gene rearrangements (e.g., EML4-ALK fusion), which are oncogenic drivers in a subset of NSCLC patients and predict response to ALK inhibitors.
* ROS1 (ROS1 Proto-Oncogene Receptor Tyrosine Kinase): FISH is also the gold standard for detecting ROS1 gene rearrangements, which similarly identify patients who will benefit from ROS1 inhibitors.
* RT-PCR (Reverse Transcription Polymerase Chain Reaction): This method is used to detect and quantify RNA, specifically mRNA transcripts, which can reveal gene fusions or specific mRNA expression levels.
* EGFR (Epidermal Growth Factor Receptor): While EGFR mutations are typically detected by DNA-based PCR or NGS, RT-PCR can be used to detect specific EGFR mRNA variants, though its primary use for EGFR in this context might be for detecting specific fusion transcripts if any are clinically relevant (less common than point mutations). More commonly, EGFR mutations (e.g., exon 19 deletions, L858R) are identified via DNA-based PCR or NGS.
* IHC (Immunohistochemistry): This technique is used to detect the presence and quantify the expression level of specific proteins in tissue sections using antibodies.
* PD-L1 (Programmed Death-Ligand 1): IHC is the standard and widely accepted method for assessing PD-L1 protein expression on tumor cells and/or immune cells. PD-L1 expression is a key biomarker for predicting response to immune checkpoint inhibitors (PD-1/PD-L1 inhibitors). The percentage of PD-L1 expression is reported as a Tumor Proportion Score (TPS) or Combined Positive Score (CPS) depending on the antibody clone used.
Note: While RT-PCR is listed for EGFR, it's important to clarify that the most common and clinically relevant EGFR alterations (activating mutations like exon 19 deletions and L858R) are typically detected by DNA-based PCR methods (like ddPCR, qPCR) or NGS. RT-PCR's strength is in RNA detection, making it highly suitable for gene fusions (like ALK or ROS1 fusions if RNA is used, though FISH is DNA-based), but often it is grouped with other PCR-based techniques. PD-L1 is strictly IHC. For ALK/ROS1, NGS-based detection of fusions is also emerging as an alternative or complementary method to FISH, and IHC can be a screening tool for ALK.
Sample Required
FFPE TISSUE > 10% CANCER
(Formalin-Fixed Paraffin-Embedded (FFPE) tumor tissue is the required sample type. It is crucial that the tissue block or scrolls submitted contain greater than 10% cancer cells to ensure sufficient tumor DNA/RNA/protein for accurate analysis. Adequate tissue fixation and processing are also important.)
Preparation
Preparation for this test involves careful handling of the tumor tissue. * Sample Type: Formalin-Fixed Paraffin-Embedded (FFPE) tumor tissue block or scrolls. This is the standard for both FISH and IH... Read more
Schedule Report
7 Days
Emergency Report
Yes
Frequently Asked Questions
No data available
Test Description
- High-end laboratory & medical equipment.
- Outstanding doctor team.
- Personalized care & high-quality service.
- Tailormade health screening packages.