Fig 1.
Representative images of 2 NSCLC cases demonstrating varying degrees of %TCmRNA and TCIHC staining.
A. Case shows 100% TC IHC staining, 66% TC mRNA staining and 2–3 dots/tumour cell. B. Case shows 70% TC IHC staining, 48% TC mRNA staining and 1–2 dots/tumour cell. Arrows indicate examples of cell nuclei with RNAScope staining.
Fig 2.
%TCmRNA (A) and dots /cell (B) comparison to TCIHC <25% (Low) vs ≥25% (High) PD-L1 expression in NSCLC, HNSCC and UC. %TCmRNA and the number of punctate dots per cell were grouped according to PD-L1 expression determined by IHC. %TCmRNA demonstrated statistical significance (at α = 0.05) in the PD-L1 high vs PD-L1 low groups for NSCLC, HNSCC and UC. The number of punctate dots/tumour cell was statistically significantly higher in the PD-L1 high vs PD-L1 low groups for NSCLC and HNSCC but not UC. Fig 2B UC plot, PD-L1 high, one outlier (7.24 dots/tumour cell) is not shown.
Table 1.
Mean %TCmRNA and dots/tumour cell staining in PD-L1 IHC high and low groups.
Fig 3.
ROC analysis was performed using %TCmRNA and dots/tumour cell in NSCLC (A), HNSCC (B) and UC (C). Based on the highest sensitivity and specificity against IHC (SP263) using a 25% cut off, ROC analysis was used to identify PD-L1High/Low thresholds for RNAScope. Maximum sensitivity and specificity are identified on each plot (•) and the threshold for %TCmRNA and dots/tumour cell given. The area under each curve (AUC) is calculated and for all indications demonstrates fair accuracy of RNAScope compared to IHC.