# PD-L1 TPS (tumour proportion score)

Source: https://onco.cc/biomarkers/pd-l1-tps/  
OnCo record `pd-l1-tps` (Biomarker). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

TPS is the share of tumour cells whose membrane stains for PD-L1, ignoring immune cells. In lung cancer it decides whether pembrolizumab or cemiplimab can be given alone: 1 percent opens the door, 50 percent is where single-agent treatment is strongest.

## Summary

The tumour proportion score is the percentage of viable tumour cells showing partial or complete membrane staining at any intensity, read on the 22C3 pharmDx (and, for cemiplimab, also the SP263 assay). Pembrolizumab's US label uses TPS >= 1 percent for first-line single-agent treatment of stage III or metastatic NSCLC without EGFR or ALK alterations and for second-line treatment after platinum chemotherapy; cemiplimab's single-agent first-line indication requires TPS >= 50 percent. The KEYNOTE-024 trial that set the 50 percent bar and KEYNOTE-042 that lowered the gate to 1 percent are the sources of the two numbers. TPS is a lung-specific read; the same slide scored as CPS would include immune cells and give a different number.

## Fields

- Kind: Biomarker
- Last checked: 2026-09-23
- Also known as: PD-L1 TPS; TPS; tumor proportion score; tumour proportion score; TPS >= 1%; TPS >= 50%; PD-L1 TPS 50; PD-L1 high; PD-L1 ≥50%; TPS≥50%; TPS≥1%
- Tags: biomarker; pd-l1

## Notes

- Gallbladder cancer: tumour proportion score 1% or more in 14.7% of 131 Western cases, above 10% in 4.7% and above 25% in 3.1% (Albrecht 2021); 23.0% at 1%, 14.9% at 10% and 7.5% at 50% with the SP263 clone in 174 Indian cases (Neyaz 2018). TPS above 10% was an independent negative prognostic factor in the Western series. No biliary approval uses a PD-L1 threshold.
- Lung cancer: the tumour proportion score is the 22C3 read, the percentage of viable tumour cells with any membrane staining over at least 100 tumour cells, with immune cells excluded. Two thresholds carry approvals: 50% or more for first-line pembrolizumab monotherapy, where progression-free survival was 10.3 against 6.0 months with chemotherapy (Reck 2016), and 1% or more for pembrolizumab after platinum (Herbst 2016). The score can be reported from a 22C3, 28-8 or SP263 stain, since the three are comparable on tumour cells across both Blueprint phases, but not from SP142, which stains fewer tumour cells (mean score 1.99 against 2.96 for 22C3) and would move tumours across the 50% line (Tsao 2018, Rimm 2017). Cytology cell blocks are acceptable and digital reading agrees with glass (Tsao 2018).

## Sources

- KEYTRUDA prescribing information (DailyMed): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=9333c79b-d487-4538-a9f0-71b91a02b287
- LIBTAYO prescribing information (DailyMed): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=4347ae1f-d397-4f18-8b70-03897e1c054a

## Connected records

- biomarkers: [PD-L1 CPS (combined positive score)](https://onco.cc/biomarkers/pd-l1-cps/), [PD-L1 IC score (immune-cell score, SP142)](https://onco.cc/biomarkers/pd-l1-ic-score/), [PD-L1 TC score (tumour-cell score, SP263 and 28-8)](https://onco.cc/biomarkers/pd-l1-tc-score/), [STK11 or KEAP1 loss in KRAS-mutant lung adenocarcinoma](https://onco.cc/biomarkers/stk11-keap1-loss/)
- cancers: [Gallbladder cancer](https://onco.cc/cancers/gallbladder/), [Lung cancer (all types)](https://onco.cc/cancers/lung-cancer/), [Non-small-cell lung cancer](https://onco.cc/cancers/nsclc/)
- drugs: [Cemiplimab](https://onco.cc/drugs/cemiplimab/), [PD-L1 IHC 22C3 pharmDx](https://onco.cc/drugs/dako-pd-l1-22c3-pharmdx/), [Pembrolizumab](https://onco.cc/drugs/pembrolizumab/), [VENTANA PD-L1 (SP263) Assay](https://onco.cc/drugs/ventana-pd-l1-sp263/)
- terms: [Immunohistochemistry (IHC)](https://onco.cc/terms/ihc/), [PD-L1 expression testing (22C3, SP142, SP263)](https://onco.cc/terms/pd-l1-testing/), [Tumour proportion score (TPS)](https://onco.cc/terms/tps/)
- key papers: [A prospective, multi-institutional, pathologist-based assessment of 4 immunohistochemistry assays for PD-L1 expression in non-small cell lung cancer](https://onco.cc/key-papers/paper-rimm-pd-l1-assay-comparison-jama-oncol-2017/), [Association of high tumor mutation burden in non-small cell lung cancers with increased immune infiltration and improved clinical outcomes of PD-L1 blockade across PD-L1 expression levels](https://onco.cc/key-papers/paper-ricciuti-tmb-pd-l1-levels-jama-oncol-2022/), [Associations of tissue tumour mutational burden and mutational status with clinical outcomes in KEYNOTE-042](https://onco.cc/key-papers/paper-keynote-042-tmb-mutations-ann-oncol-2023/), [Clinical relevance of PD-L1 expression in gallbladder cancer: a potential target for therapy](https://onco.cc/key-papers/paper-neyaz-pdl1-gallbladder-histopathology-2018/), [Immune microenvironment in gallbladder adenocarcinomas](https://onco.cc/key-papers/paper-patil-gallbladder-immune-microenvironment-aimm-2021/), [KEYNOTE-010 (Herbst 2016): pembrolizumab versus docetaxel in previously treated PD-L1-positive lung cancer](https://onco.cc/key-papers/paper-keynote-010-lancet-2016/), [KEYNOTE-024: pembrolizumab alone beats chemotherapy in PD-L1-high lung cancer](https://onco.cc/key-papers/paper-keynote-024-nejm-2016/), [Molecular determinants of response to anti-PD-1 and anti-PD-L1 blockade in patients with non-small-cell lung cancer profiled with targeted next-generation sequencing](https://onco.cc/key-papers/paper-rizvi-targeted-ngs-immunotherapy-determinants-jco-2018/), [PD-L1 Immunohistochemistry Assays for Lung Cancer: Results from Phase 1 of the Blueprint PD-L1 IHC Assay Comparison Project](https://onco.cc/key-papers/paper-hirsch-j-thorac-oncol/), [PD-L1 immunohistochemistry comparability study in real-life clinical samples: results of Blueprint phase 2 project](https://onco.cc/key-papers/paper-blueprint-phase-2-pd-l1-assays-jto-2018/), [Programmed death ligand-1 (PD-L1) is an independent negative prognosticator in Western-world gallbladder cancer](https://onco.cc/key-papers/paper-albrecht-pdl1-western-gallbladder-cancers-2021/)
- targets: [PD-L1](https://onco.cc/targets/pdl1/)

---
JSON: https://onco.cc/api/v1/entities/pd-l1-tps.json