EBV Test for Gastric Cancer: Epstein-Barr Virus Tumor Marker and Molecular Subtype
The EBV test used to classify gastric cancer is usually EBER in situ hybridization (EBER-ISH) performed on tumor tissue. It detects abundant Epstein-Barr virus-encoded...
FGFR2 Fusion Test for Cholangiocarcinoma: Gene Fusion, Positive Result, and Molecular Meaning
An FGFR2 fusion test looks for rearrangements that join the fibroblast growth factor receptor 2 gene to another gene and create an abnormally active...
Gastric Cancer Biomarker Panel: HER2, PD-L1, MSI, CLDN18.2, EBV, and Molecular Profile
A modern gastric cancer biomarker panel can directly shape first-line and later treatment. The most clinically established markers include HER2, PD-L1, microsatellite instability or...
Gastrointestinal Stromal Tumor (GIST) Biomarker Panel: KIT, PDGFRA, DOG1, and Tumor Diagnosis
GIST diagnosis combines tumor appearance under the microscope with immunohistochemistry and mutation testing. KIT (CD117) and DOG1 are the most useful immunostains for confirming...
GI Cancer Biomarker Panel: CEA, CA 19-9, MSI, KRAS, BRAF, HER2, and Tumor Profile
A GI cancer biomarker panel is not one universal blood test. It is a group of blood, pathology, and molecular tests selected according to...
Guardant Reveal Test: Colorectal Cancer ctDNA MRD and Recurrence Monitoring
Guardant Reveal is a blood-based circulating tumor DNA test designed to detect molecular residual disease after treatment for colorectal cancer. Unlike tumor-informed assays that...
HER2 Test for Colon Cancer: HER2 Expression, Amplification, and Tumor Marker Meaning
HER2 testing in colorectal cancer looks for abnormal ERBB2/HER2 activation, usually through strong protein expression and/or gene amplification. It is most relevant in metastatic...
HER2 Test for Gastric Cancer: HER2 Expression, IHC/FISH Status, and Amplification
HER2 testing in gastric and gastroesophageal junction adenocarcinoma determines whether the tumor overexpresses HER2 protein or has ERBB2 gene amplification strongly enough to qualify...
IDH1 and IDH2 Test for Cholangiocarcinoma: Mutation Status and Molecular Meaning
IDH1 and IDH2 testing in cholangiocarcinoma looks for mutations that reprogram cell metabolism and can define a targetable molecular subtype. The alterations are concentrated...
KRAS Test for Colon Cancer: Mutation Status, Anti-EGFR Resistance Marker, and Meaning
KRAS testing in colorectal cancer determines whether the tumor carries an activating RAS-pathway mutation that predicts resistance to standard anti-EGFR antibodies. The clinically relevant...
KRAS Test for Pancreatic Cancer: Tumor Mutation, Mutation Status, and Diagnostic Context
KRAS is the dominant driver gene in pancreatic ductal adenocarcinoma, with activating mutations present in roughly nine out of ten tumors. Testing can support...
Liver Cancer Biomarker Panel: AFP, DCP, PIVKA-II, AFP-L3, and HCC Risk
AFP, AFP-L3%, and DCP/PIVKA-II are blood biomarkers associated with hepatocellular carcinoma, but they do not function as a stand-alone “liver cancer panel” that can...
MLH1 Promoter Methylation Test: Colon Cancer, Lynch Syndrome Workup, and Sporadic MSI
MLH1 promoter methylation testing helps explain why a colorectal cancer has lost MLH1/PMS2 mismatch-repair proteins or shows microsatellite instability. In many older adults, MLH1...
MMR IHC Test for Colon Cancer: MLH1, MSH2, MSH6, PMS2, and Lynch Screening
Mismatch-repair immunohistochemistry (MMR IHC) is a tumor test that stains colorectal cancer cells for four DNA-repair proteins: MLH1, PMS2, MSH2, and MSH6. Intact nuclear...
MSI Test for Colon Cancer: Microsatellite Instability, Lynch Syndrome, and Mismatch Repair
An MSI test for colon cancer checks whether a tumor has trouble repairing small DNA copying errors. When this repair system fails, short repeated...
MSI Test for Gastric Cancer: Microsatellite Instability, Mismatch Repair, and Molecular Subtype
An MSI test for gastric cancer checks whether the tumor has a defective DNA mismatch repair system. When mismatch repair fails, repeated DNA sequences...
NRAS Test for Colon Cancer: Mutation Status, Anti-EGFR Resistance Marker, and Meaning
An NRAS test for colon cancer looks for activating mutations in the NRAS gene, usually as part of extended RAS testing that also includes...
NTRK Fusion Test for Colon Cancer: Gene Fusion, Tumor-Agnostic Marker, and Result Meaning
An NTRK fusion test for colon cancer looks for an abnormal joining of an NTRK gene with another gene, creating a continuously active TRK...
Oncotype DX Colon Recurrence Score Test: Colon Cancer Recurrence Risk and Genomic Score
The Oncotype DX Colon Recurrence Score test is a 12-gene tumor assay designed to estimate the risk that certain resected colon cancers will recur...
PALB2 Test for Pancreatic Cancer: DNA Repair Marker, Hereditary Risk, and Variant Meaning
A PALB2 test in pancreatic cancer looks for harmful changes in a gene that helps repair double-strand DNA breaks through homologous recombination. A pathogenic...