BRAF testing is a laboratory test that checks tumor cells (or sometimes blood) for changes in the **BRAF** gene. It is commonly used in oncology to help classify cancers and guide treatment planning. The test looks for specific DNA variants (mutations) that can affect how cancer grows and responds to certain drugs. Results are interpreted by clinicians in the context of the cancer type, stage, and other biomarkers.

NRAS testing is a laboratory test that looks for changes (mutations) in the **NRAS** gene in cancer cells. It is a type of **molecular or biomarker testing** used to better understand a tumor’s biology. It is commonly performed on tumor tissue and sometimes on blood using a “liquid biopsy” approach. Results can help clinicians refine diagnosis and guide treatment planning in selected cancers.

KRAS testing is a lab test that checks a tumor for changes (mutations) in the KRAS gene. It is commonly used in solid tumors to help classify the cancer and guide treatment planning. It usually uses tissue from a biopsy or surgery, and sometimes uses a blood sample (liquid biopsy).

EGFR mutation testing is a laboratory test that looks for specific DNA changes in the EGFR gene. It is most commonly used in certain solid tumors, especially non-small cell lung cancer. The goal is to identify tumor features that may affect diagnosis and treatment planning. Testing can be done on tumor tissue or sometimes on a blood sample.

ALK FISH is a laboratory test that looks for changes in the ALK gene in tumor cells. It uses fluorescent markers to detect ALK gene rearrangements under a microscope. It is most commonly used in certain lung cancers and some rare tumors and lymphomas. Results can help clinicians match a cancer to targeted treatments when appropriate.

HER2 FISH is a laboratory test that measures the HER2 gene in cancer cells. It uses fluorescent probes to check whether the HER2 gene is amplified (present in extra copies). It is most commonly used in breast cancer and some gastrointestinal cancers to guide treatment planning. It is performed on tumor tissue (or sometimes cell samples) reviewed by a pathology laboratory.

HER2 IHC is a laboratory test that measures HER2 protein on the surface of tumor cells. It uses immunohistochemistry (IHC), a staining method performed on a tissue sample under a microscope. HER2 IHC is commonly used in cancers where HER2 status can affect diagnosis and treatment planning. It is most widely discussed in breast cancer, and it is also used in some other solid tumors.

PD-L1 IHC is a lab test that looks for the PD-L1 protein in a cancer tissue sample. It uses immunohistochemistry (IHC), a staining method that makes certain proteins visible under a microscope. It is commonly used in oncology to help guide immunotherapy decisions and to describe tumor biology.

MMR IHC is a lab test that checks whether a tumor has working mismatch repair (MMR) proteins. It is performed on tumor tissue, most often from a biopsy or surgery specimen. MMR IHC is commonly used in cancers like colorectal and endometrial cancer to guide further testing and treatment planning. It can also help identify people who may benefit from genetic evaluation for inherited cancer risk.

MSI testing is a laboratory test that looks for a pattern of DNA changes called microsatellite instability in a tumor. It helps clinicians understand how a cancer is behaving at the molecular level. MSI testing is commonly used in colorectal and endometrial cancers, and it may be used in other tumor types. Results can inform diagnosis, inherited cancer risk evaluation, and treatment planning.