The disclosure provides methods and compositions for detecting non-hematopoietic, non-tumor EphA3-expressing cells in cancer patients and for monitoring the prognosis of patients using EphA3 as a detection marker. Specifically, the level of EphA3+ non- hematopoietic. non-tumor cells in the peripheral blood is used for diagnosing the presence of a solid tumor. The methods further comprise determining whether the EphA3+ cells express CD34, CD45, CD44, CD90, and/or KDR. Methods for treating patients having an increased level of EphA3-expressing non-hematopoietic, non-tumor cells in the blood are also described.Linvention concerne des procédés et des compositions pour détecter des cellules exprimant EphA3 non cancéreuses, non hématopoïétiques et pour surveiller le pronostic de patients en utilisant EphA3.
