Prognostic Utility of the IPS 3 Score for Predicting Outcomes in Advanced Hodgkin Lymphoma

Abstract

Micro‐Abstract The International Prognostic Scoring System, with 7 factors, the standard prognostic model used in advanced Hodgkin lymphoma (aHL) has many disadvantages. A simpler model with 3 parameters called IPS3 has been proposed. This study shows the utility of IPS3 in predicting survival in patients with aHL. Background: The International Prognostic Scoring System (IPSS) consisting of 7 parameters (IPS7) has been the standard prognostic model used in advanced Hodgkin lymphoma (aHL). However, recent studies have questioned its discriminatory power. For retrospective analyses, its utility might be limited by missing parameters. A recent study has shown that the IPSS consisting of only 3 high‐risk features (IPS3; stage IV, age 45 years or older, and hemoglobin <105 g/L) is a simple predictor of survival in aHL. However, there are limited data validating the IPS3. Patients and Methods: Outcomes of adults with aHL treated between 2001 and 2015 at a single center were retrospectively analyzed with data from medical records. The prognostic validity of various baseline parameters was assessed individually as well as in combination (IPS7 and IPS3 scores). The Kaplan–Meier method was used to describe the event‐free survival (EFS) and overall survival (OS) and univariate (log rank) and multivariate (Cox regression) tests were performed to identify prognostic factors. Results: We identified 314 patients (median age, 32 [range, 18‐60] years; male sex [n = 215; 68%]) treated during this period. IPS7 was available in 231 of 314 (73%) and IPS3 in all (100%) patients. Most (71%) were treated with 6 to 8 cycles of ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) and others received hybrid or cyclophosphamide, vincristine, procarbazine, prednisolone regimens, and 72 (23%) underwent interim positron emission tomography imaging with escalation to bleomycin, etoposide, adriamycin, cyclophosphamide, vincristine, procarbazine, prednisolone in 8 patients. After a median follow‐up of 57 months (range, 1.3‐167), the 5‐year EFS and OS were 72% and 82%, respectively. IPS3 produced a wider separation of survival curves than IPS7 in univariate analysis. In multivariate analysis for EFS, IPS3 (scores of 2 or 3 vs. scores of 0 and 1; hazard ratio, 2.1; P = .004) was the only significant predictor. For OS, no factor emerged as significant. Conclusion: The IPS3 is a simple 3‐point system that is very useful for prediction of outcomes in aHL and might be particularly suited for retrospective data analysis where all components of the IPS7 might not be available.