tumor heterogeneity
Variability in cellular characteristics within a single tumor or between different tumor sites in the same patient.
Full Definition
Tumor heterogeneity refers to the diverse cellular and molecular characteristics that exist within a single tumor mass (intratumoral heterogeneity) or between different tumor sites in the same patient (intertumoral heterogeneity). This phenomenon has significant implications for oncologic surgery as different regions of the tumor may exhibit varying degrees of aggressiveness, treatment response, and metastatic potential. Understanding tumor heterogeneity influences surgical planning, sampling strategies for pathological analysis, and decisions regarding adjuvant therapy. It also explains why targeted therapies may be effective against some tumor cells but not others within the same patient.
Usage
Usage note: Distinguish between intratumoral and intertumoral heterogeneity when discussing sampling strategies.
In Context
- "Tumor heterogeneity may explain the variable response to targeted therapy observed in this patient." — Multidisciplinary team meeting notes
- "Multiple sampling sites were obtained to account for potential tumor heterogeneity." — Pathology report