Retrospective Study of the Utility of Follicular Lymphoma International Prognostic Index (FLIPI) and FLIPI2 In Patients with Follicular Lymphoma Uniformly Treated with Rituximab, Cyclophosphamide, Doxorubicin, Vincristin, and Prednisone

Abstract 3100

The Follicular Lymphoma International Prognostic Index (FLIPI) is the most useful prognostic index for follicular lymphoma (FL). FLIPI was developed from retrospective data, which was based on treatment without rituximab (R) therapy and did not contain β2-microglobulin data of some cases. Recently the working group that had suggested FLIPI proposed FLIPI2, based on prospectively collected data. However, FLIPI2 contains data on several different treatment methods, such as treatment with or without R therapy. The present study aimed to retrospectively analyze the prognosis of FL uniformly treated with the combination of R, cyclophosphamide, doxorubicin, vincristin, and prednisone (R-CHOP). This study involved 114 patients consecutively diagnosed with FL who were treated with R-CHOP and were registered in the data-base of the Yokohama City University Hematology Group between January 2001 and October 2009. All the parameters required for FLIPI and FLIPI2 calculation were present in 108 patients (men, 53; women, 55, median age; 57 years [34- 78 years]). The median follow-up period was 31.7 months (0.8- 97.5 months). According to the FLIPI score, 50 patients (46.3%) were in the high-risk group (HR); 31 patients (28.7%), the intermediate-risk group (IR); and 27 patients (25.0%), the low-risk group (LR). On the basis of the FLIPI2 score, 45 patients (41.7%) were in HR; 52 patients (48.1%), IR; and 11 patients (10.2%), LR. According to FLIPI, the 5-year overall survival (5yOS) was 74.1% (95% CI, 58.1– 94.4%) for HR, 89.5% (95%, CI, 76.6– 100%) for IR, and 100% for LR (p = 0.0049); the 5-year time to failure (5yTTF) was 42.3% (95% CI, 26.0– 68.9%) for HR, 39.1% (95% CI, 22.7– 67.3%) for IR, 66.4% (95% CI, 47.2– 93.4%) for LR (p = 0.244). According to the FLIPI2 score, 5yOS was 71.3% (95% CI, 53.2– 95.6%) for HR, 85.6 % (95% CI, 72.0– 100%) for IR, and 100% for LR (p = 0.197), the 5yTTF was 35.8% (95% CI, 20.0– 64.2%) for HR, 46.7% (95% CI, 31.1– 70.3%) for IR, and 76.2% (95% CI, 52.1– 100%) for LR (p = 0.075). In conclusion, in FL patients treated with R-CHOP, FLIPI provided a more accurate OS than that provided by FLIPI2; however, FLIPI2 provided a more accurate TTF than that provided by FLIPI.