Early non-small cell lung cancer (NSCLC), treated by surgery or radiotherapy in the case of inoperability, relapses in almost 50% of cases. Circulating tumour cells (CTCs), which can be detected before surgery, represent a promising prognostic tool, but the markers characterising their aggressiveness remain to be determined. The NSCLC microenvironment, in which purinergic signalling is a key pathway, controls tumour development. Adenosine derived from the action of CD39 and CD73 ectonucleotidases hydrolysing extracellular ATP, induces immunosuppression of NSCLC by activating A2R receptors. The expression and prognostic relevance of A2R, CD39 and CD73 on CTCs is unknown. The objectives are to (i) compare the expression of A2R and CD39 and CD73 on primary tumour cells and CTCs of patients operated on for early NSCLC, (ii) correlate these data with molecular characteristics and clinical response, (iii) determine on lung cancer lines whether irradiation impacts on the expression of A2R, CD39 and CD73. This work could contribute to the identification of new theranostic biomarkers.