Positive results for testing Tspan8 in EVs by flow cytometry and the observed increase in Tspan8 fluorescence intensity in EVs from the blood of Tspan8 tumour‐bearing animals indicate the first hint towards the potential of Tspan8 as a non‐invasive biomarker for breast cancer, which would be useful to address in a clinical study. Here, TSPAN8 is linked to breast cancer.