Long‐term Follow‐up and Predictors of Poor Outcome in Patients With Follicular Lymphoma Undergoing Front‐line Treatment With Chemoimmunoterapy: A Single Center Experience.

Abstract

response by R-CHOP or R-CVP. Rituximab maintenance (single infusion for four weeks every six months for maximum of two years) was given to 169 patients (77%) with median duration of 1.6 years.Results: Baseline characteristics are following: aged >60 was 105 (47%), men was 92 (42%), stage III/IV was 174 (79%), nodal lesions > four sites was 118 (54%), grade 3a was 33 (15), bone marrow involvement was 84 (40%), elevated LDH was 36 (16%), hemoglobin <12 g/dl was 27 (12%), bulky disease (tumor diameter > 6 cm) was 43 (20%), β2MG > 2 mg/dl was 83 (37%), and SUV max > 10 was 48 (22%). FLIPI classified patients into 99 (45%) as low FLIPI, 55 (25%) as intermediate FLIPI, and 66 (30%) as high FLIPI, respectively. FLIPI2 classified patients into 40 (18%) as low FLIPI2, 130 (59%) as intermediate FLIPI2, and 50 (23%) as high FLIPI2, respectively. Pretreatment sIL-2R (median 871 IU/ml, range 115-13700) was significant higher in patients, who experienced a relapse. ROC curve illustrates 1070 IU/ml as adequate cut-off value to predict relapse of FL in this cohort (AUC = 0.7, 95%CI = 0.62-0.78). Elevated LDH, stage III/IV, involved nodal sites >4, bone marrow involvement, bulky disease, elevated β2MG, SUVmax >10 in PET scan, high FLIPI, and high FLIPI2 were statistically associated with high sIL-2R, respectively. At the median follow-up time of 74.2 months, the six-year PFS was 75.1% (95% CI = 66.5-81.8) in the maintenance + group versus 44.1% (95%CI = 28.5-58.6) in the maintenance group (P < 0.0000001) and 84.0% (95%CI = 74.4-90.2) in the low sIL-2R group versus 51.1% (95%CI = 39.8-61.3) in the high sIL-2R groups, respectively (P < 0.000001). The six-year PFS was 84.8%, 78.4%, 58.5%, and 48.1% in the maintenance+/low sIL-2R, maintenance-/low sIL-2R, maintenance+/high sIL-2R, and maintenance-/high sIL-2R groups, respectively (P < 0.000001). Multivariate analysis showed that high sIL-2R (hazard ratio 2.7, 95% confidential interval = 1.3-5.6, P < 0.01) was an independent factor of poor PFS as well as elevated β2MG and no rituximab maintenance.Conclusions: Pretreatment high sIL-2R level was an independent poorprognostic factor and also a surrogate marker of the presence of aggressive component in FL in this cohort. Univariate and multiple Cox regression models were used to assess the effect of covariates on PFS and OS. KeywordsResults: Median (range) age at diagnosis was 62 years (32-83).Forty-eight percent of patients had high-risk FLIPI and 36.7% were high-risk FLIPI-2. Patient characteristics are shown in the Table 1.The most commonly front-line therapies administered were R-CHOP (56.9%) and R-CVP (40%). Rituximab maintenance was administered to 48 patients (73.8%). Overall, 67.2% of patients achieved complete remission (CR) and 12.5% partial remission (PR) with no significant differences between both regimens. Conclusions:Our results show that refractoriness to chemoimmunotherapy and early progression after treatment were the most relevant variables affecting outcome of patients. Both factors should be used to stratify th...