Background: Follicular lymphoma accounts for about 20-30% of non-Hodgkin's lymphomas. Clinical behaviour and overall prognosis are highly variable, ranging from indolent forms with occasional spontaneous remissions to rapidly progressive disease.
Methods and results: Modern treatment strategies have shifted from a primarily "palliative" approach to more intensive risk-adapted therapy with the intention of achieving complete long-term remission. New targeted treatment with monoclonal antibodies (MoAb) and radioimmunoconjugates (RIT) has resulted in unprecedented improvements in treatment outcome. At the same time, a large amount of information is now available on lymphomagenesis, the role of the microenvironment of lymphomatous follicles and cytogenetic abnormalities. We can better understand the role of the patient's innate anti-lymphoma immunity. Although no standard front-line therapy has been established, increasingly more data show that risk-adapted treatment strategy have survival benefits for high-risk patients. For this reason, accurate prognostic indices are urgently needed to find optimal therapies for particular lymphoma patients. Whereas the currently used FLIPI index was established in the pre-rituximab era, the newly designed FLIPI 2 index still needs to be confirmed in prospective trials.
Conclusion: New therapeutic approaches with MoAb, RIT and other biological agents allow the population to be divided into increasing numbers of groups with different outcomes. All in all, in the near future, we will probably not use only one basic prognostic index for all populations of FL patients. New prognostic schemes should analyze patients separately and include both disease- and patient/host-related parameters.