Decreased Prognostic Value of International Prognostic Score in Chinese Advanced Hodgkin Lymphoma Patients Treated in the Contemporary Era

BACKGROUND: The International Prognostic Score (IPS) was developed based on the data of Western advanced Hodgkin lymphoma (HL) patients treated before 1992. Only a few studies ever evaluated the application value of IPS in Chinese population or in patients treated in the contemporary era whose outcomes has improved significantly than before. METHODS: We conducted a retrospective study involving 208 previously untreated Chinese advanced HL patients, who were admitted to Cancer Hospital Chinese Academy of Medical Sciences from January 1, 1999 to April 30, 2015 and received uniform first-line treatment. The prognostic value of both IPS and the seven IPS factors for freedom-from progression (FFP) and overall survival (OS) was assessed in this population. The statistical methods included Kaplan-Meier methodology, log-rank testing, and Cox proportional hazard regression analysis. RESULTS: With a median follow-up time of 79 months (range, 15–210 months), the 5-year FFP and OS were 78.8% and 86.0% respectively, which improved obviously compared with the original IPS study. The IPS remained prognostic for both FFP (P = 0.041) and OS (P = 0.013), but the range narrowed obviously, with 5-year FFP ranging from 87.2% to 61.5%, 5-year OS ranging from 94.1% to 69.2%, and the separation of survival curves was not as good as before. Only two of the seven IPS factors showed a significant independent prognostic value in the multivariate analysis: Stage IV (for FFP, hazard ratio [HR] = 2.219, 95% confidence interval [CI]: 1.148–3.948, P = 0.016; for OS, HR = 2.491, 95% CI: 1.159–5.355, P = 0.019) and hemoglobin <105 g/L (for FFP, HR = 2.136, 95% CI: 1.123–4.060, P = 0.021; for OS, HR = 2.345, 95% CI: 1.099–5.042, P = 0.028). A simple prognostic score calculated by adding one point each for any of the two factors was prognostic both for FFP (P < 0.001) and OS (P < 0.001) with the survival curves separating very well, but the range still narrowed. CONCLUSIONS: The IPS has decreased the prognostic value in Chinese advanced HL patients treated in the contemporary era. More prognostic factors are needed to supplement this original scoring system so as to identify different risk populations more accurately.