Patients with a history of stroke or intracranial hemorrhage within months prior to registration are not eligible History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke/intracranial hemorrhage =< months prior to registration History of intracranial abscess within months prior to randomization. History of stroke or intracranial hemorrhage within months prior to randomization History of stroke or intracranial hemorrhage within months of first dose History of stroke or intracranial hemorrhage within months prior to enrollment Any history of symptomatic intracranial hemorrhage. Patients should not have a stroke or intracranial hemorrhage within last months Patients will not be eligible if they have a history of intracranial hemorrhage in past months History of stroke or intracranial hemorrhage within months prior to enrollment History of ischemic stroke or intracranial hemorrhage =< days prior to pre-registration History of stroke/intracranial hemorrhage =< months prior to registration History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months of the first dose of study drug History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months before the first dose of study drug History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or cerebral hemorrhage within months History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to randomization History of stroke or intracranial hemorrhage within months prior to study entry History of stroke or cerebral hemorrhage within months History of stroke or intracranial hemorrhage within months of screening No history of intracranial hemorrhage Relapsed/refractory MCL: History of stroke or intracranial hemorrhage within months prior to signing the consent Newly diagnosed MCL: History of stroke or intracranial hemorrhage within months prior to signing the consent History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrolment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to signing the consent. History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months before randomization. History of stroke or intracranial hemorrhage within months before randomization. history of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or clinically significant intracranial hemorrhage within months before first dose of study drug. History of stroke or intracranial hemorrhage within months prior to enrollment No stroke or intracranial hemorrhage within the last months History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment. History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or cerebral hemorrhage within months Patient has history of stroke or intracranial hemorrhage =< months from starting study drugs History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to the first dose of study drug History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to study entry History of stroke or cerebral hemorrhage within months Active intracranial hemorrhage History of stroke or intracranial hemorrhage within months prior to the first dose of ibrutinib History of stroke or intracranial hemorrhage within months prior to enrollment. History of stroke or intracranial hemorrhage within months prior to enrollment. Subjects with a history of stroke or intracranial hemorrhage within months prior to enrollment are not eligible History of stroke or intracranial hemorrhage within months prior to randomization History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to random assignment History of stroke or intracranial hemorrhage within months prior to randomization; or clinically significant cardiovascular disease History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months of screening would be exclusion for ibrutinib therapy but idelalisib would be an option History of stroke or intracranial hemorrhage within months prior to registration History of stroke or intracranial hemorrhage within months prior to enrollment Patients with a history of known stroke or intracranial hemorrhage within months prior to study treatment are excluded History of stroke or intracranial hemorrhage within months prior to enrollment. History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment Patients with a history of intracranial hemorrhage are not eligible. History of stroke or intracranial hemorrhage =< months prior to registration History of stroke or intracranial hemorrhage within months prior to treatment History of stroke or cerebral hemorrhage within months History of stroke or intracranial hemorrhage within months of enrollment History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months prior to enrollment EXCLUSION CRITERIA (PRIOR TO IBRUTINIB ADMINISTRATION): History of stroke or intracranial hemorrhage within months prior to screening History of stroke or intracranial hemorrhage within months prior to enrollment History of stroke or intracranial hemorrhage within months of first dose