External Validation of the FLIPI Risk Score Measured at Diagnosis and POD24 among Individuals with Follicular Lymphoma at the Time of Subsequent Relapse.

Determining the prognosis of relapsed follicular lymphoma is challenging. We examined the Follicular Lymphoma International Prognostic Index (FLIPI) risk score and POD24 to see if they could inform prognosis at the time of relapse. In a group of 216 individuals, the FLIPI risk score at initial diagnosis was highly prognostic at the time of relapse which suggests that it may help to stratify risk among individuals with relapsed follicular lymphoma. Background: The Follicular lymphoma international prognostic index (FLIPI) risk score and POD24 have previously been shown to have prognostic value in follicular lymphoma (FL), but the extent to which they can inform prognosis at the time of subsequent relapse is uncertain. Patients and Methods: We conducted a longitudinal cohort study of individuals diagnosed with FL between 2004 and 2010 in Alberta, Canada who received front-line therapy and subsequently relapsed. FLIPI covariates were measured prior to the initiation of front-line therapy. Median overall survival (OS), progression-free survival (PFS2), and time to next treatment (TTNT2) were estimated from the time of relapse. Results: A total of 216 individuals were included. The FLIPI risk score was highly prognostic at the time of relapse for OS (c-statistic = 0.70; HR[High vs. Low] = 7.38; 95% CI: 3.05-17.88), PFS2 (c-statistic = 0.68; HR[High vs. Low] = 5.84; 95% CI: 2.93-11.62) and TTNT2 (c-statistic = 0.68; HR[High vs. Low] = 5.72; 95% CI: 2.87-11.41). POD24 was not prognostic at the time of relapse for either OS, PFS2, or TTNT2 (c-statistic = 0.55). Conclusion: The FLIPI score measured at diagnosis may help with the risk stratification of individuals with relapsed FL.