tumor-normal pair
Matched tissue samples from the same patient including both cancerous tissue and adjacent normal tissue, used to distinguish somatic from germline genetic alterations.
Full Definition
A tumor-normal pair consists of matched tissue samples from the same patient: tumor tissue containing cancer cells and normal tissue (usually adjacent normal tissue or blood) from the same individual. This paired analysis is essential for distinguishing somatic mutations (acquired during cancer development) from germline variants (inherited genetic variations). By comparing the genetic profiles of both samples, laboratories can identify alterations specific to the tumor while filtering out constitutional genetic variants. This approach improves the accuracy of variant calling and reduces false positives in genomic profiling. Tumor-only analysis is sometimes performed when normal tissue is unavailable, but requires different analytical approaches and has limitations in variant interpretation.
Usage
Usage note: Hyphenate when used as compound modifier; distinguish from tumor-only approaches which analyze cancer tissue alone.
In Context
- "Tumor-normal pair analysis identified 147 somatic mutations specific to the cancer tissue." — Genomic analysis report
- "The laboratory requires both tumor and normal tissue for comprehensive tumor-normal pair sequencing." — Test requisition form