tumor purity assessment

Full Definition

The process of determining the proportion of malignant cells relative to normal cells, stromal cells, and inflammatory cells within a tumor specimen submitted for genomic testing. Tumor purity assessment is critical for accurate interpretation of genomic results, as low purity can lead to false-negative results or underestimation of variant allele fractions. Pathologists typically perform this assessment through microscopic examination of tissue sections, and minimum purity thresholds are often required for reliable genomic testing.

Usage

Usage note: Distinguish from final tumor purity calculations derived from genomic analysis results.

In Context

• "Tumor purity assessment revealed 65% malignant cells, meeting the minimum threshold for comprehensive genomic profiling." — Pathology review note
• "Low tumor purity may require microdissection or additional tissue collection for reliable genomic testing." — Laboratory protocol