Mantle cell lymphoma (MCL) is a unique type of non-Hodgkin lymphoma first distinguished as a separate entity more than 20 years ago.1 Today, 2 clinical variants of MCL are recognized—a classic MCL (cMCL), which is an aggressive disease requiring high-intensity chemotherapy, and a less common indolent form that can be managed conservatively.2 While the indolent MCL is distinguished by its protracted course and dormant behavior, the prognosis of cMCL is less predictable. Growing evidence suggests that clinical and biological diversity of cMCL, although well established, has been underestimated, casting doubts on its reputedly aggressive nature. Accordingly, the most pressing question pertaining to cMCL management is whether an intensive, umbrella-type treatment is justified for every patient who can endure it.