Intermediate
Technical
In the Industry Vocabulary Test
biomarker
Measurable biological indicator used to assess disease state or treatment response.
Full Definition
A biomarker is a measurable biological characteristic that can be objectively evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacological responses to therapeutic intervention. In oncology, biomarkers include genetic mutations, protein expression levels, or other molecular signatures that can predict treatment response, prognosis, or toxicity risk. Examples include HER2 expression in breast cancer or PD-L1 expression for immunotherapy selection.
Usage
Usage note: One word, not hyphenated. Distinguish from surrogate endpoints in regulatory contexts.
In Context
- "The biomarker analysis identified patients most likely to benefit from targeted therapy." — Companion diagnostic report
- "Circulating tumor DNA serves as a predictive biomarker for treatment response." — Precision medicine study
Also known as
biological marker
Don't confuse with
surrogate endpoint