Surrogate endpoints in mature B-cell neoplasms - meaningful or misleading?

Indolent mature B-cell neoplasms are a group of diseases in which recent therapeutic advances have led to an improved overall survival (OS) extending beyond several years. While cause of celebration for patients and caregivers, the increasingly long observation periods necessary to capture treatment effects are complicating trial design and possibly hindering swift access to more effective therapies. Surrogate endpoints are a tool with the potential of earlier study readouts, however, their validity needs to be proven in each individual disease and therapeutic setting. The validation of surrogate endpoints and available data for mature B-cell neoplasms are discussed within this perspective article, followed by an outlook on the potential of precise tools such as measurable residual disease assessment as novel surrogate candidates.