Objective  To analyze and compare the clinical characteristics and prognosis of low-grade follicular lymphoma (FL) in different age groups.

  Methods  We obtained the data of clinical and pathological indicators from 82 patients with low-grade FL who were newly treated at The First Affiliated Hospital of Zhengzhou University from January 2011 to December 2019. The male to female ratio was 1:1.05, with a median age of 52 (19-84) years. Categorical variables were analyzed using the Chi-square test. The Kaplan-Meier method was used for survival analysis, and differences in survival were assessed using the Log-rank test. Logistic univariate analysis and Cox multivariate regression model analysis were performed to analyze the factors affecting survival.

  Results  The 2-year and 5-year overall survival (OS) and progression-free survival (PFS) rates in the 73 patients who completed follow-up were 97.2% and 74.1% and 91.5% and 88.8%, respectively. Eighty-two patients were assigned into three age groups: < 40 years, 40-59 years, and ≥ 60 years. With increasing age, patients showed a higher erythrocyte sedimentation rate (ESR), platelet to lymphocyte ratio (PLR), Eastern Cooperative Oncology Group (ECOG) score, follicular lymphoma international prognostic index-2 (FLPI-2) score, and Bcl-2 positive ratio. Moreover, the complete response rate reduced after initial treatment (P < 0.05). The 5-year OS rates in the < 40 years, 40-59 years, and ≥ 60 years age groups were 100%, 73.8%, and 46.5%, respectively (P=0.014). There was no significant difference in PFS between the groups (P=0.190). Concerning the chemotherapy regimen, the 5-year OS rates in the rituximab plus chemotherapy and chemotherapy only groups were 85.7% and 69.3%, respectively (P=0.004); the corresponding 5-year PFS rates were 96.8% and 56.3%, respectively (P < 0.001). In the chemotherapy only group, the OS rates of patients aged < 40, 40-59, and ≥ 60 years were 100.0%, 75.0%, and 71.4%, respectively (P=0.048). There was no significant difference in OS in each age group (P=0.050). With respect to the Ann Arbor stage, the OS rates of patients aged < 40, 40-59, and ≥ 60 years were 100%, 88.90%, and 47.7%, respectively, in the advantage groups (P=0.046); however, there was no significant difference in the 5-year OS of the early group (stage Ⅰ + Ⅱ) at different age stratification (P=0.414). On univariate analysis, male sex was an adverse prognostic factor, and on multivariate analysis, male sex was correlated with a poorer PFS.

  Conclusions  The prognosis of patients with low-grade FL worsens with increasing age. Male sex is a poor prognostic factor. Administration of rituximab plus chemotherapy can improve the prognosis and prolong survival.