Fig. 7

The prognostic influence of histological transformation prior to and after therapy in FL1-2 and FL3a patients. A-B Kaplan‒Meier curves of PFS A and OS B for FL3a patients with HT prior to therapy and after therapy. 5-year PFS rate for FL3a patients with HT prior to therapy (56.9%, range 0.43–0.74), in comparison with FL3a patients with HT after therapy (62.8%, range 0.45–0.86); stratified P > 0.05. 5-year OS rate for FL3a patients with HT prior to therapy (87.3%, range 0.74–1.00), in comparison with FL3a patients with HT after therapy (72.7%, range 0.53–0.99); stratified P < 0.05. C-D Kaplan‒Meier curves of PFS C and OS D for FL1-2 patients with HT prior to therapy and after therapy. 5-year PFS rate for FL1-2 patients with HT prior to therapy (57.1%, range 0.34–0.94), in comparison with FL1-2 patients with HT after therapy (52.3%, range 0.29–0.92); stratified P > 0.05. 5-year OS rate for FL1-2 patients with HT prior to therapy (81.5%, range 0.61–1.00), in comparison with FL1-2 patients with HT after therapy (67.7%, range 0.47–0.96); stratified P > 0.05