If you agree to take part in this study, you will be assigned to a dose level of lenalidomide based on when you join this study and whether any intolerable side effects were seen in previous participants. Two (2) dose levels of lenalidomide will be tested. The first group of 3 participants will receive the higher dose level of lenalidomide. If intolerable side effects are seen in the first 3 participants, the remaining participants will receive a lower dose of lenalidomide.