The interval between frontline treatment and the second relapse (PFS2) predicts survival from the second relapse in follicular lymphoma patients

Follicular lymphoma (FL) is the most frequent indolent B-cell lymphoma. The introduction of immunotherapy has greatly improved outcomes for FL patients, with a median overall survival (OS) now approaching 20 years. However, relapses are continuously seen during follow-up, and responses progressively shorten with each relapse, with a median survival after third-line therapy of 4.8 years.