Multiple treatment approaches may be effective in stage I follicular lymphoma
Several treatment regimens resulted in excellent outcomes among patients with stage I follicular lymphoma, according to study results.
Practice guidelines recommend patients with stage I follicular lymphoma undergo radiation therapy, but several other treatment approaches are used. No prospective randomized trials and few retrospective reports compared radiation to other modalities, according to background information in the study.
Jonathan W. Friedberg, MD, MMSc, acting director of the James P. Wilmot Cancer Center, chief of hematology/oncology, and director of hematological malignancies clinical research at the University of Rochester Medical Center, analyzed outcomes of 471 patients with stage I follicular lymphoma who were enrolled in the National LymphoCare database.
Researchers observed improved PFS (HR=0.63) among the 206 patients who underwent rigorous staging as defined by both a bone marrow aspirate and biopsy and an imaging study (CT scan of the whole body, a PET/CT scan, or both).
The analysis of treatment outcomes was limited to the patients who underwent rigorous staging.
The breakdown of treatments administered to that patient population was as follows: 28% received rituximab (Rituxan, Genentech/Idec Pharmaceuticals)/chemotherapy, 27% received radiation, 17% underwent observation, 13% received systemic therapy plus radiation, 12% received rituximab monotherapy and 3% received other treatments.
Median follow-up was 57 months. During that period, 21% of patients experienced progression events.
After adjustments for histology, lactate dehydrogenase and the presence of B symptoms, researchers observed significant improvements in PFS among patients assigned to rituximab/chemotherapy (HR=0.36; 95% CI, 0.16-0.82) or systemic therapy plus radiation (HR=0.11; 95% CI, 0.23-1.84) compared with patients who received radiation alone.
There was no significant difference in PFS between patients assigned to rituximab/chemotherapy and those who were treated with rituximab monotherapy (HR=-.65; 95% CI, 0.23-1.84).
Researchers did not observe differences in OS between treatment groups.
Because variable treatment approaches demonstrated similarly positive outcomes, the findings challenge the paradigm that radiation should be standard therapy for patients with stage I follicular lymphoma, the researchers said.
“Ideally, a randomized trial would be conducted to compare these various strategies, but [that] is unlikely to occur as a result of the large sample size required and the rarity of events in this patient population,” Friedberg and colleagues wrote. “As our understanding of the biology of follicular lymphoma improves, including the ability to define high-risk disease by using genetic and molecular techniques, future studies should focus efforts in these molecularly defined patient populations by using rationally targeted therapeutic approaches.”
In an accompanying editorial, Silvia Montoto, MD, clinical senior lecturer at the Centre for Haemato-Oncology at Barts Cancer Institute at Queen Mary University of London, said research on the management of localized follicular lymphoma has been “greatly neglected.”
“The question that we thought we had answered — ie, what is the standard treatment for patients with localized disease at diagnosis? — is still unresolved,” Montoto wrote. “If the paradigm is to be changed, this change has to be driven by better evidence than that which has been used to support radiation therapy as the standardized treatment for follicular lymphoma.”
Disclosure: The study was supported by Genentech. Dr. Friedberg is a consultant for Genentech.