Loading...
The development of clinically and histologically transformed lymphoma (TL), usually diffuse large B-cell lymphoma, in patients with a prior diagnosis of follicular lymphoma (FL) has historically been associated with poor outcome and short overall survival.
To assess the rates of TL in the rituximab era, investigators prospectively enrolled 631 patients with newly diagnosed FL (excluding those with grade 3b, composite lymphoma, or transformed disease at diagnosis) in an observational study between 2002 and 2009. The most common treatments were observation only (33% of patients), alkylator-based therapy with or without rituximab (22%), anthracycline-based therapy with or without rituximab (20%), and rituximab monotherapy (12%).
At a median follow-up of 60 months, 60 patients (9.5%) developed TL and 79 (12.5%) died. The rate of TL was approximately 2% per year during the first 5 years after diagnosis of FL, after which the rate seemed to slow. The overall rate of TL at 5 years was 10.7%. Increased lactate dehydrogenase (LDH) and high Follicular Lymphoma International Prognostic Index (FLIPI) score at the time of FL diagnosis were associated with increased risk for TL.
Link BK et al. Rates and outcomes of follicular lymphoma transformation in the immunochemotherapy era: A report from the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource. J Clin Oncol 2013 Sep 10; 31:3272 (http://dx.doi.org/10.1200/JCO.2012.48.3990)
Comment
The rate of transformed lymphoma in this study was lower than observed in earlier retrospective trials. The lowest rate (0.6%) was in patients initially treated with rituximab monotherapy, whereas the highest rate (3%) was in those who initially deferred treatment. Among patients who received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) after follicular lymphoma transformation, the 5-year overall survival rate was 73%, similar to that achieved by study patients who received R-CHOP for de novo diffuse large B-cell lymphoma. Patients with TL during the first 18 months after FL diagnosis experienced decreased overall survival compared with later transformation. Whether PET/CT scanning would have detected such patients at the time of FL diagnosis should be prospectively assessed. Recently identified molecular markers correlating with increased risk may also prove useful in this regard. (Blood 2013 Sep 13; [e-pub ahead of print])