PD-L1 Tumor Proportion Score Less than 1

**Semantic type:** Laboratory or Test Result

**Definition:** A semi-quantitative finding indicating that less than 1 percent of the viable tumor cells in a sample are positive for PD-L1 expression by immunostaining.

**Synonyms:** - CD274 TPS Less than 1 - PD-L1 TPS <1% - PD-L1 TPS Less than 1 - PD-L1 Tumor Proportion Score <1% - PD-L1 Tumor Proportion Score Less than 1 Percent - PDL1 TPS Less than 1 - TPS score less than 1%