Is radiotherapy still the optimal initial choice for patients with early-stage low-grade follicular lymphoma in the modern era? A population-based study.

Despite radiotherapy (RT) is recognized as preferred initial therapy for early-stage low-grade follicular lymphoma (FL) by many international practice guidelines, the medical oncologist has improperly underutilized RT, and diverse management strategies, including systemic therapy (ST), combined modality (CM) and watch and wait (WW), are still used. Except survival outcomes, previous studies concerned little about the treatment-related toxicity, which is also important factor in choosing initial management strategy, especially second primary malignancies (SPMs). The aim of this study was to compare the overall survival (OS) and the SPMs risk between different management strategies, which can provide guidance for the choice of optimal initial management strategy. Data was acquired from the Surveillance, Epidemiology, and End Results (SEER) database. Finally, A total 10,900 patients were identified, in which 930 cases developed SPMs. The use of radiotherapy (RT) has remained consistently low, with a utilization rate of around 20%, while most patients have received watchful waiting (WW) and systemic therapy (ST). In the rituximab era, multivariate analysis indicated that RT exhibited significantly superior OS and did not increase SPMs risk in comparison with ST and WW. At the same time, although there were no significant differences in OS between CM and RT, RT had significantly lower SPMs risk in comparison with CM. The use of RT improved the OS and did not increase the SPMs risk in comparison with other management strategies. Considering the low application rate of RT, oncologists should emphasize and increase the use of RT as an initial management strategy in patients with early-stage low-grade FL.