Tumor Markers
Tumor markers are tumor-specific substances in the blood serum or other tissues that can assist in determining the presence or absence of cancer. They can help determine the initial tumor burden in both the primary site and distant sites. Tumor markers can be helpful in monitoring for recurrence.
- Estrogen receptor (ER), Progesterone receptor (PR) and Human epidermal growth factor receptor 2 (HER 2) values are used to evaluate and monitor breast cancer. These values are now used to determine AJCC staging and collected as Site Specific Data Information (SSDI).
- ERs are a group of proteins found inside cells which are activated by the hormone estrogen (17β-estradiol). Approximately 80% of all breast cancers are ER positive which means the cancer cells grow in response to estrogen.
- The PR, also known as NR3C3 or nuclear receptor subfamily 3, group C, member 3, is a protein found inside cells. It is activated by the steroid hormone progesterone. Breast Cancer Hormone receptor tests (Estrogen Receptor (ER) and Progesterone Receptor (PR) when positive are both prognostic and predictive. In general, tumors that are ER+ and/or PR+ are slightly slower growing and have a slightly better prognosis than tumors that aren't.
- HER2 is a membrane tyrosine kinase and oncogene that is overexpressed, and gene amplified in about 20% of breast cancers. HER2 is a member of the human epidermal growth factor receptor (HER/EGFR/ERBB) family. Amplification or over-expression of this oncogene has been shown to play an important role in the development and progression of certain aggressive types of breast cancer.
- Prostate-specific antigen (PSA) is a substance produced by the prostate gland. Elevated levels of PSA may indicate primary prostate cancer but can also indicate non-cancerous conditions such as prostatitis or an enlarged prostate.
- Alpha Feto Protein (AFP), Human Chorionic Gonadotropin (HCG) and Lactate Dehydrogenase (LDH) for testicular primaries.
- Cancer antigen 125 (CA 125) measures the amount of protein CA 125 in your blood for ovarian primaries and is used to measure treatment effectiveness rather than diagnostic purposes.
- Human Papilloma Virus (HPV) for GYN, anal, penile, and Head and Neck primaries.
- Flow cytometry for liquid tumors.
Updated: March 4, 2024