tumor heterogeneity
The genetic and phenotypic diversity present within a single tumor or between tumors in the same patient.
Full Definition
Tumor heterogeneity refers to the genetic, epigenetic, and phenotypic differences that exist within a single tumor (intratumor heterogeneity) or between different tumor sites in the same patient (intertumor heterogeneity). This diversity results from ongoing mutagenic processes and clonal evolution during cancer progression. Tumor heterogeneity poses significant challenges for precision oncology, as it can affect the representativeness of tissue samples, the accuracy of molecular profiling, and the development of treatment resistance.
Usage
Usage note: Important consideration for sample selection and interpretation of molecular testing results.
In Context
- "Tumor heterogeneity analysis revealed distinct mutational patterns between primary and metastatic sites." — Research documentation
- "The molecular pathologist noted significant tumor heterogeneity that could impact treatment response predictions." — Clinical report