Life Expectancy of Follicular Lymphoma Patients in Complete Response at 30 Months is Similar to that of the Spanish General Population

Background: The use of immunochemotherapy has substantially increased the outcome of patients with follicular lymphoma (FL). Nowadays, life expectancy for those reaching a durable response is excellent. Recently, complete response at 30 months (CR30) has been suggested as a surrogate for progression-free survival. The aim of this study was to analyze the life expectancy of FL patients according to their status at 30 months from the start of treatment in comparison with the sex and age-matched Spanish general population (relative survival; RS). Methods: 263 patients consecutively diagnosed with FL in a 10-year period, needing therapy and treated with rituximab-containing regimens, constituted the training series. An independent cohort of 693 FL patients from the GELTAMO group was used for validation. Findings: In the training cohort, 188 patients (71%) were in complete response at 30 months, with a 10-year overall survival of 53% and 87% for non-CR30 and CR30 patients, respectively. Ten-year RS was 73% and 100%, showing no decrease in life expectancy for CR30 patients. Follicular Lymphoma International Prognostic Index (FLIPI), beta2-microglobulin and response to induction, but not maintenance therapy or PET/CT assessment after induction, predicted RS in the CR30 patients group. FLIPI was the most important variable predicting overall survival in the CR30 group in the multivariate analysis. The impact of CR30 status on RS was validated in the independent GELTAMO series. Interpretation: Follicular lymphoma patients treated with immunochemotherapy who were in complete remission at 30 months showed similar survival to that of the sex- and age-matched Spanish general population. Funding: Instituto de Salud Carlos III, Ministerio de Salud, Espana, Ministerio de Economia y Competitividad, Espana, CIBERONC, the program "Fellowship de Gilead Sciences", Spanish Group of Lymphoma and Bone Marrow Transplantation (GELTAMO). Declaration of Interest: The authors declare no conflicts of interest. Ethical Approval: All the patients gave informed consent to participate in the study according to the declaration of Helsinki and the ethical standards of the Ethic Committee of the Hospital Clinic de Barcelona and in each participating centre in accordance with institutional standards.