CCR7 and T-cell prolymphocytic leukemia: This section will focus on the more prevalent B-cell chronic lymphocytic leukemia, but it is noteworthy that for T-cell prolymphocytic leukemia, which is characterized by rapid growth of mature post-thymic prolymphocytes and numerous cytogenetic alterations [258,259], CCR7 was highly expressed in T-cell prolymphocytic leukemia and associated with cell migration, survival and invasion.