The present invention relates to the prediction of the survival time of a patient suffering from a cancer. The inventors identified in blood from healthy donors a subpopulation of Vδ1T cells that expresses CD73 and displays immunosuppressive phenotype and functions (i.e., production of immunosuppressive molecules and inhibition of T cell proliferation). Furthermore, they detected the presence of CD73+ γ T cells in immune infiltrates of freshly resected breast cancer specimens. Altogether, these data suggest that part of γ T cells infiltrated in the breast cancer microenvironment presents a regulatory phenotype characterized by CD73 expression, and are likely to display pro-tumor functions through the mechanisms they described in vitro. Thus, the invention relates to a method for predicting the survival time of a patient suffering from a cancer comprising i) determining in a sample obtained from the patient the level of Gamma/Delta T cells expressing CD73 ii) comparing the expression level determined at step i) with its predetermined reference value and iii) providing a good prognosis when the level of Gamma/Delta T cells expressing CD73 determined at step i) is lower than its predetermined reference value, or providing a bad prognosis when the level of Gamma/Delta T cells expressing CD73 determined at step i) is higher than its predetermined reference value.