Patients who are currently receiving other anticancer agents are not eligible Patients must not be receiving any other anti-cancer agents or radiotherapy at the time of study entry or while on study Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible (except leukemia patients receiving hydroxyurea, which may be continued until 24 hours prior to start of protocol therapy); patients with acute lymphoblastic leukemia may receive intrathecal therapy Currently receiving other anti-cancer agents Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving anti-platelet agents are not eligible Concurrent use of other anti-cancer agents or treatments Anti-cancer agents: Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving or plan to receive other anti-cancer agents (except hydroxyurea, which may be continued until 24 hours prior to start of protocol therapy and intrathecal chemotherapy) Concomitant medications* Corticosteroids: patients receiving corticosteroids who have not been on a stable or decreasing dose of corticosteroid for at least 7 days prior to enrollment are not eligible; if used to modify immune adverse events related to prior therapy, >= 14 days must have elapsed since last dose of corticosteroid* Investigational drugs: patients who are currently receiving another investigational drug are not eligible* Anti-cancer agents: patients who are currently receiving other anti-cancer agents are not eligible* Anti-GVHD agents post-transplant: patients who are receiving cyclosporine, tacrolimus or other agents to prevent graft-versus-host disease post bone marrow transplant are not eligible for this trial* CYP3A/CYP3A4 agents: patients who are currently receiving drugs that are strong and moderate inducers or inhibitors of CYP3A or CYP3A4 are not eligible; strong inducers or inhibitors of CYP3A4 should be avoided from 21 days prior to enrollment to the end of the study Concomitant medications* Corticosteroids: patients receiving corticosteroids who have not been on a stable or decreasing dose of corticosteroid for at least 7 days prior to enrollment are not eligible; if used to modify immune adverse events related to prior therapy, >= 14 days must have elapsed since last dose of corticosteroid* Investigational drugs: patients who are currently receiving another investigational drug are not eligible* Anti-cancer agents: patients who are currently receiving other anti-cancer agents are not eligible* Anti-GVHD agents post-transplant: patients who are receiving cyclosporine, tacrolimus or other agents to prevent graft-versus-host disease post bone marrow transplant are not eligible for this trial* CYP3A4 agents: patients who are currently receiving drugs that are strong inducers or strong inhibitors of CYP3A4 are not eligible; strong inducers or inhibitors of CYP3A4 should be avoided from 14 days prior to enrollment to the end of the study** Note: CYP3A4 inducing anti-epileptic drugs and dexamethasone for CNS tumors or metastases, on a stable dose, are allowed Patients who are currently receiving other anti-cancer agents are not eligible Patients who are currently receiving other anti-cancer agents are not eligible Concomitant medications* Corticosteroids: patients receiving corticosteroids who have not been on a stable or decreasing dose of corticosteroid for at least 7 days prior to enrollment are not eligible; if used to modify immune adverse events related to prior therapy, >= 14 days must have elapsed since last dose of corticosteroid* Investigational drugs: patients who are currently receiving another investigational drug are not eligible* Anti-cancer agents: patients who are currently receiving other anti-cancer agents are not eligible* Anti-GVHD agents post-transplant: patients who are receiving cyclosporine, tacrolimus or other agents to prevent graft-versus-host disease post bone marrow transplant are not eligible for this trial Concomitant medications* Corticosteroids: patients receiving corticosteroids who have not been on a stable or decreasing dose of corticosteroid for at least 7 days prior to enrollment are not eligible; if used to modify immune adverse events related to prior therapy, >= 14 days must have elapsed since last dose of corticosteroid* Investigational drugs: patients who are currently receiving another investigational drug are not eligible* Anti-cancer agents: patients who are currently receiving other anti-cancer agents are not eligible* Anti-GVHD agents post-transplant: patients who are receiving cyclosporine, tacrolimus or other agents to prevent graft-versus-host disease post bone marrow transplant are not eligible for this trial* CYP3A4 agents: patients who are currently receiving drugs that are strong inducers or inhibitors of CYP3A4 are not eligible; strong inducers or inhibitors of CYP3A4 should be avoided from 14 days prior to enrollment to the end of the study* CYP2C19 agents: patients who are currently receiving drugs that are strong CYP2C19 inducers (e.g., rifampin, ritonavir) or inhibitors (e.g.., fluoxetine, fluvoxamine, ticlopidine) are not eligible