The study will start with an initial 21-days of induction therapy with combination of orelabrutinib, pomalidomide and rituximab(Pro regimen) in eligible patients, following contrast computed temography(CT) to guide the next treatment. Patients whose lesions have 25% or more reduction will next receive Pro-miniCHOP-like regimen for 6 cycles. Patients with reduction less than 25% will receive R-miniCHOP-like regimen also for 6 cycles. After that, maintenance therapy with pomalidomide for two years will be given to patients undergoing Pro-miniCHOP-like regimen.