Finally, we noticed that a high ratio of pCXCR4/CXCR4 tumor expression was associated with a worse RFS in the Kaplan Meier survival curves of recurrent cancers which most likely mirrors the fact, that in recurrent disease the expression of CXCR4 is the dominant factor and is associated with a certain biological behavior of the tumor. The gene discussed is CXCR4; the disease is neoplasm.